diff --git a/meilidb-core/examples/from_file.rs b/meilidb-core/examples/from_file.rs
index 981f294ff..c04efb73c 100644
--- a/meilidb-core/examples/from_file.rs
+++ b/meilidb-core/examples/from_file.rs
@@ -4,15 +4,15 @@ use std::error::Error;
 use std::io::Write;
 use std::iter::FromIterator;
 use std::path::{Path, PathBuf};
-use std::time::{Instant, Duration};
+use std::time::{Duration, Instant};
 use std::{fs, io, sync::mpsc};
 
-use rustyline::{Editor, Config};
-use serde::{Serialize, Deserialize};
+use rustyline::{Config, Editor};
+use serde::{Deserialize, Serialize};
 use structopt::StructOpt;
 use termcolor::{Color, ColorChoice, ColorSpec, StandardStream, WriteColor};
 
-use meilidb_core::{Highlight, Database, UpdateResult};
+use meilidb_core::{Database, Highlight, UpdateResult};
 use meilidb_schema::SchemaAttr;
 
 const INDEX_NAME: &str = "default";
@@ -91,7 +91,7 @@ fn index_command(command: IndexCommand, database: Database) -> Result<(), Box<dy
     let update_fn = move |update: UpdateResult| sender.send(update.update_id).unwrap();
     let index = match database.open_index(INDEX_NAME) {
         Some(index) => index,
-        None => database.create_index(INDEX_NAME).unwrap()
+        None => database.create_index(INDEX_NAME).unwrap(),
     };
 
     let done = database.set_update_callback(INDEX_NAME, Box::new(update_fn));
@@ -108,14 +108,14 @@ fn index_command(command: IndexCommand, database: Database) -> Result<(), Box<dy
     match index.main.schema(&writer)? {
         Some(current_schema) => {
             if current_schema != schema {
-                return Err(meilidb_core::Error::SchemaDiffer.into())
+                return Err(meilidb_core::Error::SchemaDiffer.into());
             }
             writer.abort();
-        },
+        }
         None => {
             index.schema_update(&mut writer, schema)?;
             writer.commit().unwrap();
-        },
+        }
     }
 
     let mut rdr = csv::Reader::from_path(command.csv_data_path)?;
@@ -131,7 +131,9 @@ fn index_command(command: IndexCommand, database: Database) -> Result<(), Box<dy
 
         loop {
             end_of_file = !rdr.read_record(&mut raw_record)?;
-            if end_of_file { break }
+            if end_of_file {
+                break;
+            }
 
             let document: Document = match raw_record.deserialize(Some(&headers)) {
                 Ok(document) => document,
@@ -147,7 +149,9 @@ fn index_command(command: IndexCommand, database: Database) -> Result<(), Box<dy
             i += 1;
 
             if let Some(group_size) = command.update_group_size {
-                if i % group_size == 0 { break }
+                if i % group_size == 0 {
+                    break;
+                }
             }
         }
 
@@ -163,15 +167,25 @@ fn index_command(command: IndexCommand, database: Database) -> Result<(), Box<dy
 
     println!("Waiting for update {}", max_update_id);
     for id in receiver {
-        if id == max_update_id { break }
+        if id == max_update_id {
+            break;
+        }
     }
 
-    println!("database created in {:.2?} at: {:?}", start.elapsed(), command.database_path);
+    println!(
+        "database created in {:.2?} at: {:?}",
+        start.elapsed(),
+        command.database_path
+    );
 
     if let Some(path) = command.compact_to_path {
         let start = Instant::now();
         let _file = database.copy_and_compact_to_path(&path)?;
-        println!("database compacted in {:.2?} at: {:?}", start.elapsed(), path);
+        println!(
+            "database compacted in {:.2?} at: {:?}",
+            start.elapsed(),
+            path
+        );
     }
 
     Ok(())
@@ -182,7 +196,10 @@ fn display_highlights(text: &str, ranges: &[usize]) -> io::Result<()> {
     let mut highlighted = false;
 
     for range in ranges.windows(2) {
-        let [start, end] = match range { [start, end] => [*start, *end], _ => unreachable!() };
+        let [start, end] = match range {
+            [start, end] => [*start, *end],
+            _ => unreachable!(),
+        };
         if highlighted {
             stdout.set_color(ColorSpec::new().set_fg(Some(Color::Yellow)))?;
         }
@@ -221,12 +238,14 @@ fn create_highlight_areas(text: &str, highlights: &[Highlight]) -> Vec<usize> {
         let (byte_index, byte_length) = char_to_byte_range(char_index, char_length, text);
 
         match byte_indexes.entry(byte_index) {
-            Entry::Vacant(entry) => { entry.insert(byte_length); },
+            Entry::Vacant(entry) => {
+                entry.insert(byte_length);
+            }
             Entry::Occupied(mut entry) => {
                 if *entry.get() < byte_length {
                     entry.insert(byte_length);
                 }
-            },
+            }
         }
     }
 
@@ -252,22 +271,23 @@ fn create_highlight_areas(text: &str, highlights: &[Highlight]) -> Vec<usize> {
 /// ```
 fn crop_text(
     text: &str,
-    highlights: impl IntoIterator<Item=Highlight>,
+    highlights: impl IntoIterator<Item = Highlight>,
     context: usize,
-) -> (String, Vec<Highlight>)
-{
+) -> (String, Vec<Highlight>) {
     let mut highlights = highlights.into_iter().peekable();
 
-    let char_index = highlights.peek().map(|m| m.char_index as usize).unwrap_or(0);
+    let char_index = highlights
+        .peek()
+        .map(|m| m.char_index as usize)
+        .unwrap_or(0);
     let start = char_index.saturating_sub(context);
     let text = text.chars().skip(start).take(context * 2).collect();
 
     let highlights = highlights
-        .take_while(|m| {
-            (m.char_index as usize) + (m.char_length as usize) <= start + (context * 2)
-        })
-        .map(|highlight| {
-            Highlight { char_index: highlight.char_index - start as u16, ..highlight }
+        .take_while(|m| (m.char_index as usize) + (m.char_length as usize) <= start + (context * 2))
+        .map(|highlight| Highlight {
+            char_index: highlight.char_index - start as u16,
+            ..highlight
         })
         .collect();
 
@@ -276,7 +296,9 @@ fn crop_text(
 
 fn search_command(command: SearchCommand, database: Database) -> Result<(), Box<dyn Error>> {
     let env = &database.env;
-    let index = database.open_index(INDEX_NAME).expect("Could not find index");
+    let index = database
+        .open_index(INDEX_NAME)
+        .expect("Could not find index");
 
     let reader = env.read_txn().unwrap();
     let schema = index.main.schema(&reader)?;
@@ -312,10 +334,15 @@ fn search_command(command: SearchCommand, database: Database) -> Result<(), Box<
                         (true, filter)
                     };
 
-                    let attr = schema.attribute(&filter).expect("Could not find filtered attribute");
+                    let attr = schema
+                        .attribute(&filter)
+                        .expect("Could not find filtered attribute");
 
                     builder.with_filter(move |document_id| {
-                        let string: String = ref_index.document_attribute(ref_reader, document_id, attr).unwrap().unwrap();
+                        let string: String = ref_index
+                            .document_attribute(ref_reader, document_id, attr)
+                            .unwrap()
+                            .unwrap();
                         (string == "true") == positive
                     });
                 }
@@ -326,8 +353,8 @@ fn search_command(command: SearchCommand, database: Database) -> Result<(), Box<
 
                 let number_of_documents = documents.len();
                 for mut doc in documents {
-
-                    doc.highlights.sort_unstable_by_key(|m| (m.char_index, m.char_length));
+                    doc.highlights
+                        .sort_unstable_by_key(|m| (m.char_index, m.char_length));
 
                     let start_retrieve = Instant::now();
                     let result = index.document::<Document>(&reader, Some(&fields), doc.id);
@@ -340,15 +367,18 @@ fn search_command(command: SearchCommand, database: Database) -> Result<(), Box<
                                 print!("{}: ", name);
 
                                 let attr = schema.attribute(&name).unwrap();
-                                let highlights = doc.highlights.iter()
-                                                .filter(|m| SchemaAttr::new(m.attribute) == attr)
-                                                .cloned();
-                                let (text, highlights) = crop_text(&text, highlights, command.char_context);
+                                let highlights = doc
+                                    .highlights
+                                    .iter()
+                                    .filter(|m| SchemaAttr::new(m.attribute) == attr)
+                                    .cloned();
+                                let (text, highlights) =
+                                    crop_text(&text, highlights, command.char_context);
                                 let areas = create_highlight_areas(&text, &highlights);
                                 display_highlights(&text, &areas)?;
                                 println!();
                             }
-                        },
+                        }
                         Ok(None) => eprintln!("missing document"),
                         Err(e) => eprintln!("{}", e),
                     }
@@ -366,12 +396,19 @@ fn search_command(command: SearchCommand, database: Database) -> Result<(), Box<
                     println!();
                 }
 
-                eprintln!("whole documents fields retrieve took {:.2?}", retrieve_duration);
-                eprintln!("===== Found {} results in {:.2?} =====", number_of_documents, start_total.elapsed());
-            },
+                eprintln!(
+                    "whole documents fields retrieve took {:.2?}",
+                    retrieve_duration
+                );
+                eprintln!(
+                    "===== Found {} results in {:.2?} =====",
+                    number_of_documents,
+                    start_total.elapsed()
+                );
+            }
             Err(err) => {
                 println!("Error: {:?}", err);
-                break
+                break;
             }
         }
     }
diff --git a/meilidb-core/src/automaton/dfa.rs b/meilidb-core/src/automaton/dfa.rs
index eb9ff0714..6258da424 100644
--- a/meilidb-core/src/automaton/dfa.rs
+++ b/meilidb-core/src/automaton/dfa.rs
@@ -1,8 +1,5 @@
+use levenshtein_automata::{LevenshteinAutomatonBuilder as LevBuilder, DFA};
 use once_cell::sync::OnceCell;
-use levenshtein_automata::{
-    LevenshteinAutomatonBuilder as LevBuilder,
-    DFA,
-};
 
 static LEVDIST0: OnceCell<LevBuilder> = OnceCell::new();
 static LEVDIST1: OnceCell<LevBuilder> = OnceCell::new();
@@ -15,30 +12,30 @@ enum PrefixSetting {
 }
 
 fn build_dfa_with_setting(query: &str, setting: PrefixSetting) -> DFA {
-    use PrefixSetting::{Prefix, NoPrefix};
+    use PrefixSetting::{NoPrefix, Prefix};
 
     match query.len() {
-        0 ..= 4 => {
+        0..=4 => {
             let builder = LEVDIST0.get_or_init(|| LevBuilder::new(0, true));
             match setting {
-                Prefix   => builder.build_prefix_dfa(query),
+                Prefix => builder.build_prefix_dfa(query),
                 NoPrefix => builder.build_dfa(query),
             }
-        },
-        5 ..= 8 => {
+        }
+        5..=8 => {
             let builder = LEVDIST1.get_or_init(|| LevBuilder::new(1, true));
             match setting {
-                Prefix   => builder.build_prefix_dfa(query),
+                Prefix => builder.build_prefix_dfa(query),
                 NoPrefix => builder.build_dfa(query),
             }
-        },
+        }
         _ => {
             let builder = LEVDIST2.get_or_init(|| LevBuilder::new(2, true));
             match setting {
-                Prefix   => builder.build_prefix_dfa(query),
+                Prefix => builder.build_prefix_dfa(query),
                 NoPrefix => builder.build_dfa(query),
             }
-        },
+        }
     }
 }
 
diff --git a/meilidb-core/src/automaton/mod.rs b/meilidb-core/src/automaton/mod.rs
index 0f7e3137d..da398c669 100644
--- a/meilidb-core/src/automaton/mod.rs
+++ b/meilidb-core/src/automaton/mod.rs
@@ -6,14 +6,14 @@ use std::vec;
 
 use fst::{IntoStreamer, Streamer};
 use levenshtein_automata::DFA;
-use meilidb_tokenizer::{split_query_string, is_cjk};
+use meilidb_tokenizer::{is_cjk, split_query_string};
 
-use crate::store;
 use crate::error::MResult;
+use crate::store;
 
 use self::dfa::{build_dfa, build_prefix_dfa};
-use self::query_enhancer::QueryEnhancerBuilder;
 pub use self::query_enhancer::QueryEnhancer;
+use self::query_enhancer::QueryEnhancerBuilder;
 
 const NGRAMS: usize = 3;
 
@@ -27,14 +27,9 @@ impl AutomatonProducer {
         query: &str,
         main_store: store::Main,
         synonyms_store: store::Synonyms,
-    ) -> MResult<(AutomatonProducer, QueryEnhancer)>
-    {
-        let (automatons, query_enhancer) = generate_automatons(
-            reader,
-            query,
-            main_store,
-            synonyms_store,
-        )?;
+    ) -> MResult<(AutomatonProducer, QueryEnhancer)> {
+        let (automatons, query_enhancer) =
+            generate_automatons(reader, query, main_store, synonyms_store)?;
 
         Ok((AutomatonProducer { automatons }, query_enhancer))
     }
@@ -112,8 +107,7 @@ fn generate_automatons(
     query: &str,
     main_store: store::Main,
     synonym_store: store::Synonyms,
-) -> MResult<(Vec<Vec<Automaton>>, QueryEnhancer)>
-{
+) -> MResult<(Vec<Vec<Automaton>>, QueryEnhancer)> {
     let has_end_whitespace = query.chars().last().map_or(false, char::is_whitespace);
     let query_words: Vec<_> = split_query_string(query).map(str::to_lowercase).collect();
     let synonyms = match main_store.synonyms_fst(reader)? {
@@ -130,7 +124,6 @@ fn generate_automatons(
     let mut original_automatons = Vec::new();
     let mut original_words = query_words.iter().peekable();
     while let Some(word) = original_words.next() {
-
         let has_following_word = original_words.peek().is_some();
         let not_prefix_dfa = has_following_word || has_end_whitespace || word.chars().all(is_cjk);
 
@@ -148,29 +141,33 @@ fn generate_automatons(
     for n in 1..=NGRAMS {
         let mut ngrams = query_words.windows(n).enumerate().peekable();
         while let Some((query_index, ngram_slice)) = ngrams.next() {
-
             let query_range = query_index..query_index + n;
             let ngram_nb_words = ngram_slice.len();
             let ngram = ngram_slice.join(" ");
 
             let has_following_word = ngrams.peek().is_some();
-            let not_prefix_dfa = has_following_word || has_end_whitespace || ngram.chars().all(is_cjk);
+            let not_prefix_dfa =
+                has_following_word || has_end_whitespace || ngram.chars().all(is_cjk);
 
             // automaton of synonyms of the ngrams
             let normalized = normalize_str(&ngram);
-            let lev = if not_prefix_dfa { build_dfa(&normalized) } else { build_prefix_dfa(&normalized) };
+            let lev = if not_prefix_dfa {
+                build_dfa(&normalized)
+            } else {
+                build_prefix_dfa(&normalized)
+            };
 
             let mut stream = synonyms.search(&lev).into_stream();
             while let Some(base) = stream.next() {
-
                 // only trigger alternatives when the last word has been typed
                 // i.e. "new " do not but "new yo" triggers alternatives to "new york"
                 let base = std::str::from_utf8(base).unwrap();
                 let base_nb_words = split_query_string(base).count();
-                if ngram_nb_words != base_nb_words { continue }
+                if ngram_nb_words != base_nb_words {
+                    continue;
+                }
 
                 if let Some(synonyms) = synonym_store.synonyms(reader, base.as_bytes())? {
-
                     let mut stream = synonyms.into_stream();
                     while let Some(synonyms) = stream.next() {
                         let synonyms = std::str::from_utf8(synonyms).unwrap();
@@ -178,7 +175,11 @@ fn generate_automatons(
                         let nb_synonym_words = synonyms_words.len();
 
                         let real_query_index = automaton_index;
-                        enhancer_builder.declare(query_range.clone(), real_query_index, &synonyms_words);
+                        enhancer_builder.declare(
+                            query_range.clone(),
+                            real_query_index,
+                            &synonyms_words,
+                        );
 
                         for synonym in synonyms_words {
                             let automaton = if nb_synonym_words == 1 {
diff --git a/meilidb-core/src/automaton/query_enhancer.rs b/meilidb-core/src/automaton/query_enhancer.rs
index 165c1b094..7a949934b 100644
--- a/meilidb-core/src/automaton/query_enhancer.rs
+++ b/meilidb-core/src/automaton/query_enhancer.rs
@@ -1,5 +1,5 @@
+use std::cmp::Ordering::{Equal, Greater, Less};
 use std::ops::Range;
-use std::cmp::Ordering::{Less, Greater, Equal};
 
 /// Return `true` if the specified range can accept the given replacements words.
 /// Returns `false` if the replacements words are already present in the original query
@@ -34,13 +34,14 @@ use std::cmp::Ordering::{Less, Greater, Equal};
 //  [new york city]
 //
 fn rewrite_range_with<S, T>(query: &[S], range: Range<usize>, words: &[T]) -> bool
-where S: AsRef<str>,
-      T: AsRef<str>,
+where
+    S: AsRef<str>,
+    T: AsRef<str>,
 {
     if words.len() <= range.len() {
         // there is fewer or equal replacement words
         // than there is already in the replaced range
-        return false
+        return false;
     }
 
     // retrieve the part to rewrite but with the length
@@ -49,7 +50,9 @@ where S: AsRef<str>,
 
     // check if the original query doesn't already contain
     // the replacement words
-    !original.map(AsRef::as_ref).eq(words.iter().map(AsRef::as_ref))
+    !original
+        .map(AsRef::as_ref)
+        .eq(words.iter().map(AsRef::as_ref))
 }
 
 type Origin = usize;
@@ -68,11 +71,20 @@ impl FakeIntervalTree {
     fn query(&self, point: usize) -> Option<(Range<usize>, (Origin, RealLength))> {
         let element = self.intervals.binary_search_by(|(r, _)| {
             if point >= r.start {
-                if point < r.end { Equal } else { Less }
-            } else { Greater }
+                if point < r.end {
+                    Equal
+                } else {
+                    Less
+                }
+            } else {
+                Greater
+            }
         });
 
-        let n = match element { Ok(n) => n, Err(n) => n };
+        let n = match element {
+            Ok(n) => n,
+            Err(n) => n,
+        };
 
         match self.intervals.get(n) {
             Some((range, value)) if range.contains(&point) => Some((range.clone(), *value)),
@@ -91,9 +103,13 @@ impl<S: AsRef<str>> QueryEnhancerBuilder<'_, S> {
     pub fn new(query: &[S]) -> QueryEnhancerBuilder<S> {
         // we initialize origins query indices based on their positions
         let origins: Vec<_> = (0..query.len() + 1).collect();
-        let real_to_origin = origins.iter().map(|&o| (o..o+1, (o, 1))).collect();
+        let real_to_origin = origins.iter().map(|&o| (o..o + 1, (o, 1))).collect();
 
-        QueryEnhancerBuilder { query, origins, real_to_origin }
+        QueryEnhancerBuilder {
+            query,
+            origins,
+            real_to_origin,
+        }
     }
 
     /// Update the final real to origin query indices mapping.
@@ -101,12 +117,12 @@ impl<S: AsRef<str>> QueryEnhancerBuilder<'_, S> {
     /// `range` is the original words range that this `replacement` words replace
     /// and `real` is the first real query index of these replacement words.
     pub fn declare<T>(&mut self, range: Range<usize>, real: usize, replacement: &[T])
-    where T: AsRef<str>,
+    where
+        T: AsRef<str>,
     {
         // check if the range of original words
         // can be rewritten with the replacement words
         if rewrite_range_with(self.query, range.clone(), replacement) {
-
             // this range can be replaced so we need to
             // modify the origins accordingly
             let offset = replacement.len() - range.len();
@@ -126,7 +142,8 @@ impl<S: AsRef<str>> QueryEnhancerBuilder<'_, S> {
         // we need to pad real query indices
         let real_range = real..real + replacement.len().max(range.len());
         let real_length = replacement.len();
-        self.real_to_origin.push((real_range, (range.start, real_length)));
+        self.real_to_origin
+            .push((real_range, (range.start, real_length)));
     }
 
     pub fn build(self) -> QueryEnhancer {
@@ -148,10 +165,10 @@ impl QueryEnhancer {
         let real = real as usize;
 
         // query the fake interval tree with the real query index
-        let (range, (origin, real_length)) =
-            self.real_to_origin
-                .query(real)
-                .expect("real has never been declared");
+        let (range, (origin, real_length)) = self
+            .real_to_origin
+            .query(real)
+            .expect("real has never been declared");
 
         // if `real` is the end bound of the range
         if (range.start + real_length - 1) == real {
@@ -160,7 +177,10 @@ impl QueryEnhancer {
             for (i, slice) in self.origins[new_origin..].windows(2).enumerate() {
                 let len = slice[1] - slice[0];
                 count = count.saturating_sub(len);
-                if count == 0 { new_origin = origin + i; break }
+                if count == 0 {
+                    new_origin = origin + i;
+                    break;
+                }
             }
 
             let n = real - range.start;
@@ -168,15 +188,20 @@ impl QueryEnhancer {
             let end = self.origins[new_origin + 1];
             let remaining = (end - start) - n;
 
-            Range { start: (start + n) as u32, end: (start + n + remaining) as u32 }
-
+            Range {
+                start: (start + n) as u32,
+                end: (start + n + remaining) as u32,
+            }
         } else {
             // just return the origin along with
             // the real position of the word
             let n = real as usize - range.start;
             let origin = self.origins[origin];
 
-            Range { start: (origin + n) as u32, end: (origin + n + 1) as u32 }
+            Range {
+                start: (origin + n) as u32,
+                end: (origin + n + 1) as u32,
+            }
         }
     }
 }
@@ -382,16 +407,16 @@ mod tests {
 
         let enhancer = builder.build();
 
-        assert_eq!(enhancer.replacement(0),  0..1); // great
-        assert_eq!(enhancer.replacement(1),  1..2); // awesome
-        assert_eq!(enhancer.replacement(2),  2..5); // NYC
-        assert_eq!(enhancer.replacement(3),  5..7); // subway
-        assert_eq!(enhancer.replacement(4),  2..3); // new
-        assert_eq!(enhancer.replacement(5),  3..4); // york
-        assert_eq!(enhancer.replacement(6),  4..5); // city
-        assert_eq!(enhancer.replacement(7),  5..6); // underground
-        assert_eq!(enhancer.replacement(8),  6..7); // train
-        assert_eq!(enhancer.replacement(9),  0..2); // good
+        assert_eq!(enhancer.replacement(0), 0..1); // great
+        assert_eq!(enhancer.replacement(1), 1..2); // awesome
+        assert_eq!(enhancer.replacement(2), 2..5); // NYC
+        assert_eq!(enhancer.replacement(3), 5..7); // subway
+        assert_eq!(enhancer.replacement(4), 2..3); // new
+        assert_eq!(enhancer.replacement(5), 3..4); // york
+        assert_eq!(enhancer.replacement(6), 4..5); // city
+        assert_eq!(enhancer.replacement(7), 5..6); // underground
+        assert_eq!(enhancer.replacement(8), 6..7); // train
+        assert_eq!(enhancer.replacement(9), 0..2); // good
         assert_eq!(enhancer.replacement(10), 1..5); // NY
         assert_eq!(enhancer.replacement(11), 2..5); // metro
     }
diff --git a/meilidb-core/src/criterion/document_id.rs b/meilidb-core/src/criterion/document_id.rs
index 15549da24..e4a402d26 100644
--- a/meilidb-core/src/criterion/document_id.rs
+++ b/meilidb-core/src/criterion/document_id.rs
@@ -1,6 +1,6 @@
-use std::cmp::Ordering;
 use crate::criterion::Criterion;
 use crate::RawDocument;
+use std::cmp::Ordering;
 
 #[derive(Debug, Clone, Copy)]
 pub struct DocumentId;
diff --git a/meilidb-core/src/criterion/exact.rs b/meilidb-core/src/criterion/exact.rs
index 94c4d2746..3f4c4a974 100644
--- a/meilidb-core/src/criterion/exact.rs
+++ b/meilidb-core/src/criterion/exact.rs
@@ -1,8 +1,8 @@
 use std::cmp::Ordering;
 
+use meilidb_schema::SchemaAttr;
 use sdset::Set;
 use slice_group_by::GroupBy;
-use meilidb_schema::SchemaAttr;
 
 use crate::criterion::Criterion;
 use crate::RawDocument;
@@ -13,8 +13,7 @@ fn number_exact_matches(
     attribute: &[u16],
     is_exact: &[bool],
     fields_counts: &Set<(SchemaAttr, u64)>,
-) -> usize
-{
+) -> usize {
     let mut count = 0;
     let mut index = 0;
 
@@ -22,12 +21,16 @@ fn number_exact_matches(
         let len = group.len();
 
         let mut found_exact = false;
-        for (pos, _) in is_exact[index..index + len].iter().filter(|x| **x).enumerate() {
+        for (pos, _) in is_exact[index..index + len]
+            .iter()
+            .filter(|x| **x)
+            .enumerate()
+        {
             found_exact = true;
             if let Ok(pos) = fields_counts.binary_search_by_key(&attribute[pos], |(a, _)| a.0) {
                 let (_, count) = fields_counts[pos];
                 if count == 1 {
-                    return usize::max_value()
+                    return usize::max_value();
                 }
             }
         }
@@ -81,18 +84,18 @@ mod tests {
     #[test]
     fn easy_case() {
         let doc0 = {
-            let query_index   = &[0];
-            let attribute     = &[0];
-            let is_exact      = &[true];
+            let query_index = &[0];
+            let attribute = &[0];
+            let is_exact = &[true];
             let fields_counts = Set::new(&[(SchemaAttr(0), 2)]).unwrap();
 
             number_exact_matches(query_index, attribute, is_exact, fields_counts)
         };
 
         let doc1 = {
-            let query_index   = &[0];
-            let attribute     = &[0];
-            let is_exact      = &[false];
+            let query_index = &[0];
+            let attribute = &[0];
+            let is_exact = &[false];
             let fields_counts = Set::new(&[(SchemaAttr(0), 2)]).unwrap();
 
             number_exact_matches(query_index, attribute, is_exact, fields_counts)
@@ -108,18 +111,18 @@ mod tests {
     #[test]
     fn basic() {
         let doc0 = {
-            let query_index   = &[0];
-            let attribute     = &[0];
-            let is_exact      = &[true];
+            let query_index = &[0];
+            let attribute = &[0];
+            let is_exact = &[true];
             let fields_counts = Set::new(&[(SchemaAttr(0), 1)]).unwrap();
 
             number_exact_matches(query_index, attribute, is_exact, fields_counts)
         };
 
         let doc1 = {
-            let query_index   = &[0];
-            let attribute     = &[0];
-            let is_exact      = &[true];
+            let query_index = &[0];
+            let attribute = &[0];
+            let is_exact = &[true];
             let fields_counts = Set::new(&[(SchemaAttr(0), 4)]).unwrap();
 
             number_exact_matches(query_index, attribute, is_exact, fields_counts)
diff --git a/meilidb-core/src/criterion/mod.rs b/meilidb-core/src/criterion/mod.rs
index ad02d3023..e94b1b2c7 100644
--- a/meilidb-core/src/criterion/mod.rs
+++ b/meilidb-core/src/criterion/mod.rs
@@ -1,24 +1,20 @@
-mod sum_of_typos;
+mod document_id;
+mod exact;
 mod number_of_words;
-mod words_proximity;
+mod sort_by_attr;
+mod sum_of_typos;
 mod sum_of_words_attribute;
 mod sum_of_words_position;
-mod exact;
-mod sort_by_attr;
-mod document_id;
+mod words_proximity;
 
-use std::cmp::Ordering;
 use crate::RawDocument;
+use std::cmp::Ordering;
 
 pub use self::{
-    sum_of_typos::SumOfTypos,
-    number_of_words::NumberOfWords,
+    document_id::DocumentId, exact::Exact, number_of_words::NumberOfWords,
+    sort_by_attr::SortByAttr, sum_of_typos::SumOfTypos,
+    sum_of_words_attribute::SumOfWordsAttribute, sum_of_words_position::SumOfWordsPosition,
     words_proximity::WordsProximity,
-    sum_of_words_attribute::SumOfWordsAttribute,
-    sum_of_words_position::SumOfWordsPosition,
-    exact::Exact,
-    sort_by_attr::SortByAttr,
-    document_id::DocumentId,
 };
 
 pub trait Criterion: Send + Sync {
@@ -62,17 +58,18 @@ impl<T: Criterion + ?Sized> Criterion for Box<T> {
 
 #[derive(Default)]
 pub struct CriteriaBuilder<'a> {
-    inner: Vec<Box<dyn Criterion + 'a>>
+    inner: Vec<Box<dyn Criterion + 'a>>,
 }
 
-impl<'a> CriteriaBuilder<'a>
-{
+impl<'a> CriteriaBuilder<'a> {
     pub fn new() -> CriteriaBuilder<'a> {
         CriteriaBuilder { inner: Vec::new() }
     }
 
     pub fn with_capacity(capacity: usize) -> CriteriaBuilder<'a> {
-        CriteriaBuilder { inner: Vec::with_capacity(capacity) }
+        CriteriaBuilder {
+            inner: Vec::with_capacity(capacity),
+        }
     }
 
     pub fn reserve(&mut self, additional: usize) {
@@ -80,14 +77,16 @@ impl<'a> CriteriaBuilder<'a>
     }
 
     pub fn add<C: 'a>(mut self, criterion: C) -> CriteriaBuilder<'a>
-    where C: Criterion,
+    where
+        C: Criterion,
     {
         self.push(criterion);
         self
     }
 
     pub fn push<C: 'a>(&mut self, criterion: C)
-    where C: Criterion,
+    where
+        C: Criterion,
     {
         self.inner.push(Box::new(criterion));
     }
diff --git a/meilidb-core/src/criterion/number_of_words.rs b/meilidb-core/src/criterion/number_of_words.rs
index 641385fb1..6c1218e2f 100644
--- a/meilidb-core/src/criterion/number_of_words.rs
+++ b/meilidb-core/src/criterion/number_of_words.rs
@@ -1,7 +1,7 @@
-use std::cmp::Ordering;
-use slice_group_by::GroupBy;
 use crate::criterion::Criterion;
 use crate::RawDocument;
+use slice_group_by::GroupBy;
+use std::cmp::Ordering;
 
 #[inline]
 fn number_of_query_words(query_index: &[u32]) -> usize {
diff --git a/meilidb-core/src/criterion/sort_by_attr.rs b/meilidb-core/src/criterion/sort_by_attr.rs
index c19062dd6..632a4657c 100644
--- a/meilidb-core/src/criterion/sort_by_attr.rs
+++ b/meilidb-core/src/criterion/sort_by_attr.rs
@@ -2,9 +2,9 @@ use std::cmp::Ordering;
 use std::error::Error;
 use std::fmt;
 
-use meilidb_schema::{Schema, SchemaAttr};
 use crate::criterion::Criterion;
-use crate::{RawDocument, RankedMap};
+use crate::{RankedMap, RawDocument};
+use meilidb_schema::{Schema, SchemaAttr};
 
 /// An helper struct that permit to sort documents by
 /// some of their stored attributes.
@@ -51,8 +51,7 @@ impl<'a> SortByAttr<'a> {
         ranked_map: &'a RankedMap,
         schema: &Schema,
         attr_name: &str,
-    ) -> Result<SortByAttr<'a>, SortByAttrError>
-    {
+    ) -> Result<SortByAttr<'a>, SortByAttrError> {
         SortByAttr::new(ranked_map, schema, attr_name, false)
     }
 
@@ -60,8 +59,7 @@ impl<'a> SortByAttr<'a> {
         ranked_map: &'a RankedMap,
         schema: &Schema,
         attr_name: &str,
-    ) -> Result<SortByAttr<'a>, SortByAttrError>
-    {
+    ) -> Result<SortByAttr<'a>, SortByAttrError> {
         SortByAttr::new(ranked_map, schema, attr_name, true)
     }
 
@@ -70,8 +68,7 @@ impl<'a> SortByAttr<'a> {
         schema: &Schema,
         attr_name: &str,
         reversed: bool,
-    ) -> Result<SortByAttr<'a>, SortByAttrError>
-    {
+    ) -> Result<SortByAttr<'a>, SortByAttrError> {
         let attr = match schema.attribute(attr_name) {
             Some(attr) => attr,
             None => return Err(SortByAttrError::AttributeNotFound),
@@ -81,7 +78,11 @@ impl<'a> SortByAttr<'a> {
             return Err(SortByAttrError::AttributeNotRegisteredForRanking);
         }
 
-        Ok(SortByAttr { ranked_map, attr, reversed })
+        Ok(SortByAttr {
+            ranked_map,
+            attr,
+            reversed,
+        })
     }
 }
 
@@ -93,11 +94,15 @@ impl<'a> Criterion for SortByAttr<'a> {
         match (lhs, rhs) {
             (Some(lhs), Some(rhs)) => {
                 let order = lhs.cmp(&rhs);
-                if self.reversed { order.reverse() } else { order }
-            },
-            (None,    Some(_)) => Ordering::Greater,
-            (Some(_), None)    => Ordering::Less,
-            (None,    None)    => Ordering::Equal,
+                if self.reversed {
+                    order.reverse()
+                } else {
+                    order
+                }
+            }
+            (None, Some(_)) => Ordering::Greater,
+            (Some(_), None) => Ordering::Less,
+            (None, None) => Ordering::Equal,
         }
     }
 
@@ -122,4 +127,4 @@ impl fmt::Display for SortByAttrError {
     }
 }
 
-impl Error for SortByAttrError { }
+impl Error for SortByAttrError {}
diff --git a/meilidb-core/src/criterion/sum_of_typos.rs b/meilidb-core/src/criterion/sum_of_typos.rs
index 9fbf0dab9..5cad73b42 100644
--- a/meilidb-core/src/criterion/sum_of_typos.rs
+++ b/meilidb-core/src/criterion/sum_of_typos.rs
@@ -11,10 +11,10 @@ use crate::RawDocument;
 #[inline]
 fn custom_log10(n: u8) -> f32 {
     match n {
-        0 => 0.0,       // log(1)
-        1 => 0.30102,   // log(2)
-        2 => 0.47712,   // log(3)
-        3 => 0.60205,   // log(4)
+        0 => 0.0,     // log(1)
+        1 => 0.30102, // log(2)
+        2 => 0.47712, // log(3)
+        3 => 0.60205, // log(4)
         _ => panic!("invalid number"),
     }
 }
diff --git a/meilidb-core/src/criterion/sum_of_words_attribute.rs b/meilidb-core/src/criterion/sum_of_words_attribute.rs
index 2bf052159..472d771b7 100644
--- a/meilidb-core/src/criterion/sum_of_words_attribute.rs
+++ b/meilidb-core/src/criterion/sum_of_words_attribute.rs
@@ -1,7 +1,7 @@
-use std::cmp::Ordering;
-use slice_group_by::GroupBy;
 use crate::criterion::Criterion;
 use crate::RawDocument;
+use slice_group_by::GroupBy;
+use std::cmp::Ordering;
 
 #[inline]
 fn sum_matches_attributes(query_index: &[u32], attribute: &[u16]) -> usize {
diff --git a/meilidb-core/src/criterion/sum_of_words_position.rs b/meilidb-core/src/criterion/sum_of_words_position.rs
index d5dd10ab7..70b8843dc 100644
--- a/meilidb-core/src/criterion/sum_of_words_position.rs
+++ b/meilidb-core/src/criterion/sum_of_words_position.rs
@@ -1,7 +1,7 @@
-use std::cmp::Ordering;
-use slice_group_by::GroupBy;
 use crate::criterion::Criterion;
 use crate::RawDocument;
+use slice_group_by::GroupBy;
+use std::cmp::Ordering;
 
 #[inline]
 fn sum_matches_attribute_index(query_index: &[u32], word_index: &[u16]) -> usize {
diff --git a/meilidb-core/src/criterion/words_proximity.rs b/meilidb-core/src/criterion/words_proximity.rs
index ed3775b50..579bc7b8c 100644
--- a/meilidb-core/src/criterion/words_proximity.rs
+++ b/meilidb-core/src/criterion/words_proximity.rs
@@ -1,7 +1,7 @@
-use std::cmp::{self, Ordering};
-use slice_group_by::GroupBy;
 use crate::criterion::Criterion;
 use crate::RawDocument;
+use slice_group_by::GroupBy;
+use std::cmp::{self, Ordering};
 
 const MAX_DISTANCE: u16 = 8;
 
@@ -19,7 +19,9 @@ fn index_proximity(lhs: u16, rhs: u16) -> u16 {
 }
 
 fn attribute_proximity((lattr, lwi): (u16, u16), (rattr, rwi): (u16, u16)) -> u16 {
-    if lattr != rattr { return MAX_DISTANCE }
+    if lattr != rattr {
+        return MAX_DISTANCE;
+    }
     index_proximity(lwi, rwi)
 }
 
@@ -42,15 +44,18 @@ fn matches_proximity(
     distance: &[u8],
     attribute: &[u16],
     word_index: &[u16],
-) -> u16
-{
+) -> u16 {
     let mut query_index_groups = query_index.linear_group();
     let mut proximity = 0;
     let mut index = 0;
 
     let get_attr_wi = |index: usize, group_len: usize| {
         // retrieve the first distance group (with the lowest values)
-        let len = distance[index..index + group_len].linear_group().next().unwrap().len();
+        let len = distance[index..index + group_len]
+            .linear_group()
+            .next()
+            .unwrap()
+            .len();
 
         let rattr = &attribute[index..index + len];
         let rwi = &word_index[index..index + len];
@@ -110,7 +115,6 @@ mod tests {
 
     #[test]
     fn three_different_attributes() {
-
         // "soup" "of the" "the day"
         //
         // { id: 0, attr: 0, attr_index: 0 }
@@ -120,19 +124,21 @@ mod tests {
         // { id: 3, attr: 3, attr_index: 1 }
 
         let query_index = &[0, 1, 2, 2, 3];
-        let distance    = &[0, 0, 0, 0, 0];
-        let attribute   = &[0, 1, 1, 2, 3];
-        let word_index  = &[0, 0, 1, 0, 1];
+        let distance = &[0, 0, 0, 0, 0];
+        let attribute = &[0, 1, 1, 2, 3];
+        let word_index = &[0, 0, 1, 0, 1];
 
         //   soup -> of = 8
         // + of -> the  = 1
         // + the -> day = 8 (not 1)
-        assert_eq!(matches_proximity(query_index, distance, attribute, word_index), 17);
+        assert_eq!(
+            matches_proximity(query_index, distance, attribute, word_index),
+            17
+        );
     }
 
     #[test]
     fn two_different_attributes() {
-
         // "soup day" "soup of the day"
         //
         // { id: 0, attr: 0, attr_index: 0 }
@@ -143,13 +149,16 @@ mod tests {
         // { id: 3, attr: 1, attr_index: 3 }
 
         let query_index = &[0, 0, 1, 2, 3, 3];
-        let distance    = &[0, 0, 0, 0, 0, 0];
-        let attribute   = &[0, 1, 1, 1, 0, 1];
-        let word_index  = &[0, 0, 1, 2, 1, 3];
+        let distance = &[0, 0, 0, 0, 0, 0];
+        let attribute = &[0, 1, 1, 1, 0, 1];
+        let word_index = &[0, 0, 1, 2, 1, 3];
 
         //   soup -> of = 1
         // + of -> the  = 1
         // + the -> day = 1
-        assert_eq!(matches_proximity(query_index, distance, attribute, word_index), 3);
+        assert_eq!(
+            matches_proximity(query_index, distance, attribute, word_index),
+            3
+        );
     }
 }
diff --git a/meilidb-core/src/database.rs b/meilidb-core/src/database.rs
index 035b7e7a4..64da2d5f9 100644
--- a/meilidb-core/src/database.rs
+++ b/meilidb-core/src/database.rs
@@ -1,13 +1,13 @@
-use std::collections::hash_map::{HashMap, Entry};
+use std::collections::hash_map::{Entry, HashMap};
 use std::fs::File;
 use std::path::Path;
 use std::sync::{Arc, RwLock};
 use std::{fs, thread};
 
-use zlmdb::{Result as ZResult, CompactionOption};
-use zlmdb::types::{Str, Unit};
 use crossbeam_channel::Receiver;
 use log::{debug, error};
+use zlmdb::types::{Str, Unit};
+use zlmdb::{CompactionOption, Result as ZResult};
 
 use crate::{store, update, Index, MResult};
 
@@ -32,20 +32,32 @@ fn update_awaiter(
         loop {
             let mut writer = match env.write_txn() {
                 Ok(writer) => writer,
-                Err(e) => { error!("LMDB writer transaction begin failed: {}", e); break }
+                Err(e) => {
+                    error!("LMDB writer transaction begin failed: {}", e);
+                    break;
+                }
             };
 
             match update::update_task(&mut writer, index.clone()) {
                 Ok(Some(status)) => {
-                    if let Err(e) = writer.commit() { error!("update transaction failed: {}", e) }
+                    if let Err(e) = writer.commit() {
+                        error!("update transaction failed: {}", e)
+                    }
 
                     if let Some(ref callback) = *update_fn.load() {
                         (callback)(status);
                     }
-                },
+                }
                 // no more updates to handle for now
-                Ok(None) => { debug!("no more updates"); writer.abort(); break },
-                Err(e) => { error!("update task failed: {}", e); writer.abort() },
+                Ok(None) => {
+                    debug!("no more updates");
+                    writer.abort();
+                    break;
+                }
+                Err(e) => {
+                    error!("update task failed: {}", e);
+                    writer.abort()
+                }
             }
         }
     }
@@ -76,14 +88,16 @@ impl Database {
         // open the previously aggregated indexes
         let mut indexes = HashMap::new();
         for index_name in must_open {
-
             let (sender, receiver) = crossbeam_channel::bounded(100);
             let index = match store::open(&env, &index_name, sender.clone())? {
                 Some(index) => index,
                 None => {
-                    log::warn!("the index {} doesn't exist or has not all the databases", index_name);
+                    log::warn!(
+                        "the index {} doesn't exist or has not all the databases",
+                        index_name
+                    );
                     continue;
-                },
+                }
             };
             let update_fn = Arc::new(ArcSwapFn::empty());
 
@@ -100,10 +114,18 @@ impl Database {
             sender.send(()).unwrap();
 
             let result = indexes.insert(index_name, (index, update_fn, handle));
-            assert!(result.is_none(), "The index should not have been already open");
+            assert!(
+                result.is_none(),
+                "The index should not have been already open"
+            );
         }
 
-        Ok(Database { env, common_store, indexes_store, indexes: RwLock::new(indexes) })
+        Ok(Database {
+            env,
+            common_store,
+            indexes_store,
+            indexes: RwLock::new(indexes),
+        })
     }
 
     pub fn open_index(&self, name: impl AsRef<str>) -> Option<Index> {
@@ -152,7 +174,7 @@ impl Database {
                 let update_fn = Some(Arc::new(update_fn));
                 current_update_fn.swap(update_fn);
                 true
-            },
+            }
             None => false,
         }
     }
@@ -160,7 +182,10 @@ impl Database {
     pub fn unset_update_callback(&self, name: impl AsRef<str>) -> bool {
         let indexes_lock = self.indexes.read().unwrap();
         match indexes_lock.get(name.as_ref()) {
-            Some((_, current_update_fn, _)) => { current_update_fn.swap(None); true },
+            Some((_, current_update_fn, _)) => {
+                current_update_fn.swap(None);
+                true
+            }
             None => false,
         }
     }
diff --git a/meilidb-core/src/distinct_map.rs b/meilidb-core/src/distinct_map.rs
index c53ad0ea4..e53592afe 100644
--- a/meilidb-core/src/distinct_map.rs
+++ b/meilidb-core/src/distinct_map.rs
@@ -1,5 +1,5 @@
-use std::hash::Hash;
 use hashbrown::HashMap;
+use std::hash::Hash;
 
 pub struct DistinctMap<K> {
     inner: HashMap<K, usize>,
diff --git a/meilidb-core/src/error.rs b/meilidb-core/src/error.rs
index 3523b0ad5..a39164341 100644
--- a/meilidb-core/src/error.rs
+++ b/meilidb-core/src/error.rs
@@ -1,6 +1,6 @@
-use std::{error, fmt, io};
+use crate::serde::{DeserializerError, SerializerError};
 use serde_json::Error as SerdeJsonError;
-use crate::serde::{SerializerError, DeserializerError};
+use std::{error, fmt, io};
 
 pub type MResult<T> = Result<T, Error>;
 
@@ -90,7 +90,7 @@ impl fmt::Display for Error {
     }
 }
 
-impl error::Error for Error { }
+impl error::Error for Error {}
 
 #[derive(Debug)]
 pub enum UnsupportedOperation {
diff --git a/meilidb-core/src/lib.rs b/meilidb-core/src/lib.rs
index 67ea20762..6beef461e 100644
--- a/meilidb-core/src/lib.rs
+++ b/meilidb-core/src/lib.rs
@@ -1,7 +1,9 @@
 #[cfg(test)]
-#[macro_use] extern crate assert_matches;
+#[macro_use]
+extern crate assert_matches;
 
 mod automaton;
+pub mod criterion;
 mod database;
 mod distinct_map;
 mod error;
@@ -9,31 +11,41 @@ mod number;
 mod query_builder;
 mod ranked_map;
 mod raw_document;
-mod reordered_attrs;
-mod update;
-pub mod criterion;
 pub mod raw_indexer;
+mod reordered_attrs;
 pub mod serde;
 pub mod store;
+mod update;
 
-pub use self::database::{Database, BoxUpdateFn};
+pub use self::database::{BoxUpdateFn, Database};
 pub use self::error::{Error, MResult};
 pub use self::number::{Number, ParseNumberError};
 pub use self::ranked_map::RankedMap;
 pub use self::raw_document::RawDocument;
 pub use self::store::Index;
-pub use self::update::{UpdateStatus, UpdateResult, UpdateType};
+pub use self::update::{UpdateResult, UpdateStatus, UpdateType};
 
+use ::serde::{Deserialize, Serialize};
 use zerocopy::{AsBytes, FromBytes};
-use ::serde::{Serialize, Deserialize};
 
 /// Represent an internally generated document unique identifier.
 ///
 /// It is used to inform the database the document you want to deserialize.
 /// Helpful for custom ranking.
-#[derive(Debug, Copy, Clone, Eq, PartialEq, PartialOrd, Ord, Hash)]
-#[derive(Serialize, Deserialize)]
-#[derive(AsBytes, FromBytes)]
+#[derive(
+    Debug,
+    Copy,
+    Clone,
+    Eq,
+    PartialEq,
+    PartialOrd,
+    Ord,
+    Hash,
+    Serialize,
+    Deserialize,
+    AsBytes,
+    FromBytes,
+)]
 #[repr(C)]
 pub struct DocumentId(pub u64);
 
@@ -42,8 +54,7 @@ pub struct DocumentId(pub u64);
 ///
 /// This is stored in the map, generated at index time,
 /// extracted and interpreted at search time.
-#[derive(Debug, Copy, Clone, PartialEq, Eq, PartialOrd, Ord, Hash)]
-#[derive(AsBytes, FromBytes)]
+#[derive(Debug, Copy, Clone, PartialEq, Eq, PartialOrd, Ord, Hash, AsBytes, FromBytes)]
 #[repr(C)]
 pub struct DocIndex {
     /// The document identifier where the word was found.
@@ -109,7 +120,10 @@ pub struct Document {
 impl Document {
     #[cfg(not(test))]
     fn from_raw(raw: RawDocument) -> Document {
-        Document { id: raw.id, highlights: raw.highlights }
+        Document {
+            id: raw.id,
+            highlights: raw.highlights,
+        }
     }
 
     #[cfg(test)]
@@ -134,7 +148,11 @@ impl Document {
             matches.push(match_);
         }
 
-        Document { id: raw.id, matches, highlights: raw.highlights }
+        Document {
+            id: raw.id,
+            matches,
+            highlights: raw.highlights,
+        }
     }
 }
 
diff --git a/meilidb-core/src/number.rs b/meilidb-core/src/number.rs
index 5e64cc78f..ff3419008 100644
--- a/meilidb-core/src/number.rs
+++ b/meilidb-core/src/number.rs
@@ -1,12 +1,11 @@
-use std::num::{ParseIntError, ParseFloatError};
-use std::str::FromStr;
 use std::fmt;
+use std::num::{ParseFloatError, ParseIntError};
+use std::str::FromStr;
 
 use ordered_float::OrderedFloat;
-use serde::{Serialize, Deserialize};
+use serde::{Deserialize, Serialize};
 
-#[derive(Serialize, Deserialize)]
-#[derive(Debug, Copy, Clone, PartialEq, Eq, PartialOrd, Ord, Hash)]
+#[derive(Serialize, Deserialize, Debug, Copy, Clone, PartialEq, Eq, PartialOrd, Ord, Hash)]
 pub enum Number {
     Unsigned(u64),
     Signed(i64),
@@ -32,7 +31,11 @@ impl FromStr for Number {
             Err(error) => error,
         };
 
-        Err(ParseNumberError { uint_error, int_error, float_error })
+        Err(ParseNumberError {
+            uint_error,
+            int_error,
+            float_error,
+        })
     }
 }
 
@@ -46,10 +49,17 @@ pub struct ParseNumberError {
 impl fmt::Display for ParseNumberError {
     fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
         if self.uint_error == self.int_error {
-            write!(f, "can not parse number: {}, {}", self.uint_error, self.float_error)
+            write!(
+                f,
+                "can not parse number: {}, {}",
+                self.uint_error, self.float_error
+            )
         } else {
-            write!(f, "can not parse number: {}, {}, {}",
-                self.uint_error, self.int_error, self.float_error)
+            write!(
+                f,
+                "can not parse number: {}, {}, {}",
+                self.uint_error, self.int_error, self.float_error
+            )
         }
     }
 }
diff --git a/meilidb-core/src/query_builder.rs b/meilidb-core/src/query_builder.rs
index 26a366c49..6226067c7 100644
--- a/meilidb-core/src/query_builder.rs
+++ b/meilidb-core/src/query_builder.rs
@@ -2,17 +2,17 @@ use hashbrown::HashMap;
 use std::mem;
 use std::ops::Range;
 use std::rc::Rc;
-use std::time::{Instant, Duration};
+use std::time::{Duration, Instant};
 
 use fst::{IntoStreamer, Streamer};
 use sdset::SetBuf;
 use slice_group_by::{GroupBy, GroupByMut};
 
 use crate::automaton::{Automaton, AutomatonProducer, QueryEnhancer};
-use crate::distinct_map::{DistinctMap, BufferedDistinctMap};
-use crate::raw_document::{RawDocument, raw_documents_from};
-use crate::{Document, DocumentId, Highlight, TmpMatch, criterion::Criteria};
-use crate::{store, MResult, reordered_attrs::ReorderedAttrs};
+use crate::distinct_map::{BufferedDistinctMap, DistinctMap};
+use crate::raw_document::{raw_documents_from, RawDocument};
+use crate::{criterion::Criteria, Document, DocumentId, Highlight, TmpMatch};
+use crate::{reordered_attrs::ReorderedAttrs, store, MResult};
 
 pub struct QueryBuilder<'c, 'f, 'd> {
     criteria: Criteria<'c>,
@@ -29,8 +29,7 @@ pub struct QueryBuilder<'c, 'f, 'd> {
 fn multiword_rewrite_matches(
     mut matches: Vec<(DocumentId, TmpMatch)>,
     query_enhancer: &QueryEnhancer,
-) -> SetBuf<(DocumentId, TmpMatch)>
-{
+) -> SetBuf<(DocumentId, TmpMatch)> {
     let mut padded_matches = Vec::with_capacity(matches.len());
 
     // we sort the matches by word index to make them rewritable
@@ -38,7 +37,6 @@ fn multiword_rewrite_matches(
 
     // for each attribute of each document
     for same_document_attribute in matches.linear_group_by_key(|(id, m)| (*id, m.attribute)) {
-
         // padding will only be applied
         // to word indices in the same attribute
         let mut padding = 0;
@@ -47,18 +45,20 @@ fn multiword_rewrite_matches(
         // for each match at the same position
         // in this document attribute
         while let Some(same_word_index) = iter.next() {
-
             // find the biggest padding
             let mut biggest = 0;
             for (id, match_) in same_word_index {
-
                 let mut replacement = query_enhancer.replacement(match_.query_index);
                 let replacement_len = replacement.len();
                 let nexts = iter.remainder().linear_group_by_key(|(_, m)| m.word_index);
 
                 if let Some(query_index) = replacement.next() {
                     let word_index = match_.word_index + padding as u16;
-                    let match_ = TmpMatch { query_index, word_index, ..match_.clone() };
+                    let match_ = TmpMatch {
+                        query_index,
+                        word_index,
+                        ..match_.clone()
+                    };
                     padded_matches.push((*id, match_));
                 }
 
@@ -67,22 +67,30 @@ fn multiword_rewrite_matches(
                 // look ahead and if there already is a match
                 // corresponding to this padding word, abort the padding
                 'padding: for (x, next_group) in nexts.enumerate() {
-
                     for (i, query_index) in replacement.clone().enumerate().skip(x) {
                         let word_index = match_.word_index + padding as u16 + (i + 1) as u16;
-                        let padmatch = TmpMatch { query_index, word_index, ..match_.clone() };
+                        let padmatch = TmpMatch {
+                            query_index,
+                            word_index,
+                            ..match_.clone()
+                        };
 
                         for (_, nmatch_) in next_group {
                             let mut rep = query_enhancer.replacement(nmatch_.query_index);
                             let query_index = rep.next().unwrap();
                             if query_index == padmatch.query_index {
-
                                 if !found {
                                     // if we find a corresponding padding for the
                                     // first time we must push preceding paddings
-                                    for (i, query_index) in replacement.clone().enumerate().take(i) {
-                                        let word_index = match_.word_index + padding as u16 + (i + 1) as u16;
-                                        let match_ = TmpMatch { query_index, word_index, ..match_.clone() };
+                                    for (i, query_index) in replacement.clone().enumerate().take(i)
+                                    {
+                                        let word_index =
+                                            match_.word_index + padding as u16 + (i + 1) as u16;
+                                        let match_ = TmpMatch {
+                                            query_index,
+                                            word_index,
+                                            ..match_.clone()
+                                        };
                                         padded_matches.push((*id, match_));
                                         biggest = biggest.max(i + 1);
                                     }
@@ -97,7 +105,7 @@ fn multiword_rewrite_matches(
 
                     // if we do not find a corresponding padding in the
                     // next groups so stop here and pad what was found
-                    break
+                    break;
                 }
 
                 if !found {
@@ -105,7 +113,11 @@ fn multiword_rewrite_matches(
                     // we must insert the entire padding
                     for (i, query_index) in replacement.enumerate() {
                         let word_index = match_.word_index + padding as u16 + (i + 1) as u16;
-                        let match_ = TmpMatch { query_index, word_index, ..match_.clone() };
+                        let match_ = TmpMatch {
+                            query_index,
+                            word_index,
+                            ..match_.clone()
+                        };
                         padded_matches.push((*id, match_));
                     }
 
@@ -132,13 +144,17 @@ fn fetch_raw_documents(
     main_store: &store::Main,
     postings_lists_store: &store::PostingsLists,
     documents_fields_counts_store: &store::DocumentsFieldsCounts,
-) -> MResult<Vec<RawDocument>>
-{
+) -> MResult<Vec<RawDocument>> {
     let mut matches = Vec::new();
     let mut highlights = Vec::new();
 
     for automaton in automatons {
-        let Automaton { index, is_exact, query_len, .. } = automaton;
+        let Automaton {
+            index,
+            is_exact,
+            query_len,
+            ..
+        } = automaton;
         let dfa = automaton.dfa();
 
         let words = match main_store.words_fst(reader)? {
@@ -210,8 +226,7 @@ impl<'c, 'f, 'd> QueryBuilder<'c, 'f, 'd> {
         postings_lists: store::PostingsLists,
         documents_fields_counts: store::DocumentsFieldsCounts,
         synonyms: store::Synonyms,
-    ) -> QueryBuilder<'c, 'f, 'd>
-    {
+    ) -> QueryBuilder<'c, 'f, 'd> {
         QueryBuilder::with_criteria(
             main,
             postings_lists,
@@ -227,8 +242,7 @@ impl<'c, 'f, 'd> QueryBuilder<'c, 'f, 'd> {
         documents_fields_counts: store::DocumentsFieldsCounts,
         synonyms: store::Synonyms,
         criteria: Criteria<'c>,
-    ) -> QueryBuilder<'c, 'f, 'd>
-    {
+    ) -> QueryBuilder<'c, 'f, 'd> {
         QueryBuilder {
             criteria,
             searchable_attrs: None,
@@ -245,7 +259,8 @@ impl<'c, 'f, 'd> QueryBuilder<'c, 'f, 'd> {
 
 impl<'c, 'f, 'd> QueryBuilder<'c, 'f, 'd> {
     pub fn with_filter<F>(&mut self, function: F)
-    where F: Fn(DocumentId) -> bool + 'f,
+    where
+        F: Fn(DocumentId) -> bool + 'f,
     {
         self.filter = Some(Box::new(function))
     }
@@ -255,13 +270,16 @@ impl<'c, 'f, 'd> QueryBuilder<'c, 'f, 'd> {
     }
 
     pub fn with_distinct<F, K>(&mut self, function: F, size: usize)
-    where F: Fn(DocumentId) -> Option<u64> + 'd,
+    where
+        F: Fn(DocumentId) -> Option<u64> + 'd,
     {
         self.distinct = Some((Box::new(function), size))
     }
 
     pub fn add_searchable_attribute(&mut self, attribute: u16) {
-        let reorders = self.searchable_attrs.get_or_insert_with(ReorderedAttrs::new);
+        let reorders = self
+            .searchable_attrs
+            .get_or_insert_with(ReorderedAttrs::new);
         reorders.insert_attribute(attribute);
     }
 
@@ -270,41 +288,36 @@ impl<'c, 'f, 'd> QueryBuilder<'c, 'f, 'd> {
         reader: &zlmdb::RoTxn,
         query: &str,
         range: Range<usize>,
-    ) -> MResult<Vec<Document>>
-    {
+    ) -> MResult<Vec<Document>> {
         match self.distinct {
-            Some((distinct, distinct_size)) => {
-                raw_query_with_distinct(
-                    reader,
-                    query,
-                    range,
-                    self.filter,
-                    distinct,
-                    distinct_size,
-                    self.timeout,
-                    self.criteria,
-                    self.searchable_attrs,
-                    self.main_store,
-                    self.postings_lists_store,
-                    self.documents_fields_counts_store,
-                    self.synonyms_store,
-                )
-            },
-            None => {
-                raw_query(
-                    reader,
-                    query,
-                    range,
-                    self.filter,
-                    self.timeout,
-                    self.criteria,
-                    self.searchable_attrs,
-                    self.main_store,
-                    self.postings_lists_store,
-                    self.documents_fields_counts_store,
-                    self.synonyms_store,
-                )
-            }
+            Some((distinct, distinct_size)) => raw_query_with_distinct(
+                reader,
+                query,
+                range,
+                self.filter,
+                distinct,
+                distinct_size,
+                self.timeout,
+                self.criteria,
+                self.searchable_attrs,
+                self.main_store,
+                self.postings_lists_store,
+                self.documents_fields_counts_store,
+                self.synonyms_store,
+            ),
+            None => raw_query(
+                reader,
+                query,
+                range,
+                self.filter,
+                self.timeout,
+                self.criteria,
+                self.searchable_attrs,
+                self.main_store,
+                self.postings_lists_store,
+                self.documents_fields_counts_store,
+                self.synonyms_store,
+            ),
         }
     }
 }
@@ -326,7 +339,8 @@ fn raw_query<'c, FI>(
     documents_fields_counts_store: store::DocumentsFieldsCounts,
     synonyms_store: store::Synonyms,
 ) -> MResult<Vec<Document>>
-where FI: Fn(DocumentId) -> bool,
+where
+    FI: Fn(DocumentId) -> bool,
 {
     // We delegate the filter work to the distinct query builder,
     // specifying a distinct rule that has no effect.
@@ -347,18 +361,14 @@ where FI: Fn(DocumentId) -> bool,
             postings_lists_store,
             documents_fields_counts_store,
             synonyms_store,
-        )
+        );
     }
 
     let start_processing = Instant::now();
     let mut raw_documents_processed = Vec::with_capacity(range.len());
 
-    let (automaton_producer, query_enhancer) = AutomatonProducer::new(
-        reader,
-        query,
-        main_store,
-        synonyms_store,
-    )?;
+    let (automaton_producer, query_enhancer) =
+        AutomatonProducer::new(reader, query, main_store, synonyms_store)?;
 
     let mut automaton_producer = automaton_producer.into_iter();
     let mut automatons = Vec::new();
@@ -382,7 +392,7 @@ where FI: Fn(DocumentId) -> bool,
         // stop processing when time is running out
         if let Some(timeout) = timeout {
             if !raw_documents_processed.is_empty() && start_processing.elapsed() > timeout {
-                break
+                break;
             }
         }
 
@@ -409,20 +419,27 @@ where FI: Fn(DocumentId) -> bool,
 
                     // we have sort enough documents if the last document sorted is after
                     // the end of the requested range, we can continue to the next criterion
-                    if documents_seen >= range.end { continue 'criteria }
+                    if documents_seen >= range.end {
+                        continue 'criteria;
+                    }
                 }
             }
         }
 
         // once we classified the documents related to the current
         // automatons we save that as the next valid result
-        let iter = raw_documents.into_iter().skip(range.start).take(range.len());
+        let iter = raw_documents
+            .into_iter()
+            .skip(range.start)
+            .take(range.len());
         raw_documents_processed.clear();
         raw_documents_processed.extend(iter);
 
         // stop processing when time is running out
         if let Some(timeout) = timeout {
-            if start_processing.elapsed() > timeout { break }
+            if start_processing.elapsed() > timeout {
+                break;
+            }
         }
     }
 
@@ -456,18 +473,15 @@ fn raw_query_with_distinct<'c, FI, FD>(
     documents_fields_counts_store: store::DocumentsFieldsCounts,
     synonyms_store: store::Synonyms,
 ) -> MResult<Vec<Document>>
-where FI: Fn(DocumentId) -> bool,
-      FD: Fn(DocumentId) -> Option<u64>,
+where
+    FI: Fn(DocumentId) -> bool,
+    FD: Fn(DocumentId) -> Option<u64>,
 {
     let start_processing = Instant::now();
     let mut raw_documents_processed = Vec::new();
 
-    let (automaton_producer, query_enhancer) = AutomatonProducer::new(
-        reader,
-        query,
-        main_store,
-        synonyms_store,
-    )?;
+    let (automaton_producer, query_enhancer) =
+        AutomatonProducer::new(reader, query, main_store, synonyms_store)?;
 
     let mut automaton_producer = automaton_producer.into_iter();
     let mut automatons = Vec::new();
@@ -491,7 +505,7 @@ where FI: Fn(DocumentId) -> bool,
         // stop processing when time is running out
         if let Some(timeout) = timeout {
             if !raw_documents_processed.is_empty() && start_processing.elapsed() > timeout {
-                break
+                break;
             }
         }
 
@@ -528,7 +542,7 @@ where FI: Fn(DocumentId) -> bool,
                             Some(filter) => {
                                 let entry = filter_map.entry(document.id);
                                 *entry.or_insert_with(|| (filter)(document.id))
-                            },
+                            }
                             None => true,
                         };
 
@@ -543,7 +557,9 @@ where FI: Fn(DocumentId) -> bool,
                         }
 
                         // the requested range end is reached: stop computing distinct
-                        if buf_distinct.len() >= range.end { break }
+                        if buf_distinct.len() >= range.end {
+                            break;
+                        }
                     }
 
                     documents_seen += group.len();
@@ -558,7 +574,9 @@ where FI: Fn(DocumentId) -> bool,
 
                     // we have sort enough documents if the last document sorted is after
                     // the end of the requested range, we can continue to the next criterion
-                    if buf_distinct.len() >= range.end { continue 'criteria }
+                    if buf_distinct.len() >= range.end {
+                        continue 'criteria;
+                    }
                 }
             }
         }
@@ -583,14 +601,18 @@ where FI: Fn(DocumentId) -> bool,
 
                 if distinct_accepted && seen.len() > range.start {
                     raw_documents_processed.push(document);
-                    if raw_documents_processed.len() == range.len() { break }
+                    if raw_documents_processed.len() == range.len() {
+                        break;
+                    }
                 }
             }
         }
 
         // stop processing when time is running out
         if let Some(timeout) = timeout {
-            if start_processing.elapsed() > timeout { break }
+            if start_processing.elapsed() > timeout {
+                break;
+            }
         }
     }
 
@@ -611,20 +633,20 @@ mod tests {
     use std::collections::{BTreeSet, HashMap};
     use std::iter::FromIterator;
 
-    use fst::{Set, IntoStreamer};
+    use fst::{IntoStreamer, Set};
+    use meilidb_schema::SchemaAttr;
     use sdset::SetBuf;
     use tempfile::TempDir;
-    use meilidb_schema::SchemaAttr;
 
     use crate::automaton::normalize_str;
     use crate::database::Database;
-    use crate::DocIndex;
     use crate::store::Index;
+    use crate::DocIndex;
 
     fn set_from_stream<'f, I, S>(stream: I) -> Set
     where
-        I: for<'a> fst::IntoStreamer<'a, Into=S, Item=&'a [u8]>,
-        S: 'f + for<'a> fst::Streamer<'a, Item=&'a [u8]>,
+        I: for<'a> fst::IntoStreamer<'a, Into = S, Item = &'a [u8]>,
+        S: 'f + for<'a> fst::Streamer<'a, Item = &'a [u8]>,
     {
         let mut builder = fst::SetBuilder::memory();
         builder.extend_stream(stream).unwrap();
@@ -687,14 +709,23 @@ mod tests {
 
             let word = word.to_lowercase();
 
-            let alternatives = match self.index.synonyms.synonyms(&writer, word.as_bytes()).unwrap() {
+            let alternatives = match self
+                .index
+                .synonyms
+                .synonyms(&writer, word.as_bytes())
+                .unwrap()
+            {
                 Some(alternatives) => alternatives,
                 None => fst::Set::default(),
             };
 
             let new = sdset_into_fstset(&new);
-            let new_alternatives = set_from_stream(alternatives.op().add(new.into_stream()).r#union());
-            self.index.synonyms.put_synonyms(&mut writer, word.as_bytes(), &new_alternatives).unwrap();
+            let new_alternatives =
+                set_from_stream(alternatives.op().add(new.into_stream()).r#union());
+            self.index
+                .synonyms
+                .put_synonyms(&mut writer, word.as_bytes(), &new_alternatives)
+                .unwrap();
 
             let synonyms = match self.index.main.synonyms_fst(&writer).unwrap() {
                 Some(synonyms) => synonyms,
@@ -702,14 +733,17 @@ mod tests {
             };
 
             let synonyms_fst = insert_key(&synonyms, word.as_bytes());
-            self.index.main.put_synonyms_fst(&mut writer, &synonyms_fst).unwrap();
+            self.index
+                .main
+                .put_synonyms_fst(&mut writer, &synonyms_fst)
+                .unwrap();
 
             writer.commit().unwrap();
         }
     }
 
     impl<'a> FromIterator<(&'a str, &'a [DocIndex])> for TempDatabase {
-        fn from_iter<I: IntoIterator<Item=(&'a str, &'a [DocIndex])>>(iter: I) -> Self {
+        fn from_iter<I: IntoIterator<Item = (&'a str, &'a [DocIndex])>>(iter: I) -> Self {
             let tempdir = TempDir::new().unwrap();
             let database = Database::open_or_create(&tempdir).unwrap();
             let index = database.create_index("default").unwrap();
@@ -724,7 +758,10 @@ mod tests {
             for (word, indexes) in iter {
                 let word = word.to_lowercase().into_bytes();
                 words_fst.insert(word.clone());
-                postings_lists.entry(word).or_insert_with(Vec::new).extend_from_slice(indexes);
+                postings_lists
+                    .entry(word)
+                    .or_insert_with(Vec::new)
+                    .extend_from_slice(indexes);
                 for idx in indexes {
                     fields_counts.insert((idx.document_id, idx.attribute, idx.word_index), 1);
                 }
@@ -736,31 +773,33 @@ mod tests {
 
             for (word, postings_list) in postings_lists {
                 let postings_list = SetBuf::from_dirty(postings_list);
-                index.postings_lists.put_postings_list(&mut writer, &word, &postings_list).unwrap();
+                index
+                    .postings_lists
+                    .put_postings_list(&mut writer, &word, &postings_list)
+                    .unwrap();
             }
 
             for ((docid, attr, _), count) in fields_counts {
-                let prev = index.documents_fields_counts
-                    .document_field_count(
-                        &mut writer,
-                        docid,
-                        SchemaAttr(attr),
-                    ).unwrap();
+                let prev = index
+                    .documents_fields_counts
+                    .document_field_count(&mut writer, docid, SchemaAttr(attr))
+                    .unwrap();
 
                 let prev = prev.unwrap_or(0);
 
-                index.documents_fields_counts
-                    .put_document_field_count(
-                        &mut writer,
-                        docid,
-                        SchemaAttr(attr),
-                        prev + count,
-                    ).unwrap();
+                index
+                    .documents_fields_counts
+                    .put_document_field_count(&mut writer, docid, SchemaAttr(attr), prev + count)
+                    .unwrap();
             }
 
             writer.commit().unwrap();
 
-            TempDatabase { database, index, _tempdir: tempdir }
+            TempDatabase {
+                database,
+                index,
+                _tempdir: tempdir,
+            }
         }
     }
 
@@ -768,8 +807,8 @@ mod tests {
     fn simple() {
         let store = TempDatabase::from_iter(vec![
             ("iphone", &[doc_char_index(0, 0, 0)][..]),
-            ("from",   &[doc_char_index(0, 1, 1)][..]),
-            ("apple",  &[doc_char_index(0, 2, 2)][..]),
+            ("from", &[doc_char_index(0, 1, 1)][..]),
+            ("apple", &[doc_char_index(0, 2, 2)][..]),
         ]);
 
         let env = &store.database.env;
@@ -791,9 +830,7 @@ mod tests {
 
     #[test]
     fn simple_synonyms() {
-        let mut store = TempDatabase::from_iter(vec![
-            ("hello", &[doc_index(0, 0)][..]),
-        ]);
+        let mut store = TempDatabase::from_iter(vec![("hello", &[doc_index(0, 0)][..])]);
 
         store.add_synonym("bonjour", SetBuf::from_dirty(vec!["hello"]));
 
@@ -825,9 +862,7 @@ mod tests {
 
     #[test]
     fn prefix_synonyms() {
-        let mut store = TempDatabase::from_iter(vec![
-            ("hello", &[doc_index(0, 0)][..]),
-        ]);
+        let mut store = TempDatabase::from_iter(vec![("hello", &[doc_index(0, 0)][..])]);
 
         store.add_synonym("bonjour", SetBuf::from_dirty(vec!["hello"]));
         store.add_synonym("salut", SetBuf::from_dirty(vec!["hello"]));
@@ -872,9 +907,7 @@ mod tests {
 
     #[test]
     fn levenshtein_synonyms() {
-        let mut store = TempDatabase::from_iter(vec![
-            ("hello", &[doc_index(0, 0)][..]),
-        ]);
+        let mut store = TempDatabase::from_iter(vec![("hello", &[doc_index(0, 0)][..])]);
 
         store.add_synonym("salutation", SetBuf::from_dirty(vec!["hello"]));
 
@@ -907,9 +940,9 @@ mod tests {
     #[test]
     fn harder_synonyms() {
         let mut store = TempDatabase::from_iter(vec![
-            ("hello",   &[doc_index(0, 0)][..]),
+            ("hello", &[doc_index(0, 0)][..]),
             ("bonjour", &[doc_index(1, 3)]),
-            ("salut",   &[doc_index(2, 5)]),
+            ("salut", &[doc_index(2, 5)]),
         ]);
 
         store.add_synonym("hello", SetBuf::from_dirty(vec!["bonjour", "salut"]));
@@ -987,17 +1020,22 @@ mod tests {
     /// Unique word has multi-word synonyms
     fn unique_to_multiword_synonyms() {
         let mut store = TempDatabase::from_iter(vec![
-            ("new",    &[doc_char_index(0, 0, 0)][..]),
-            ("york",   &[doc_char_index(0, 1, 1)][..]),
-            ("city",   &[doc_char_index(0, 2, 2)][..]),
+            ("new", &[doc_char_index(0, 0, 0)][..]),
+            ("york", &[doc_char_index(0, 1, 1)][..]),
+            ("city", &[doc_char_index(0, 2, 2)][..]),
             ("subway", &[doc_char_index(0, 3, 3)][..]),
-
-            ("NY",     &[doc_char_index(1, 0, 0)][..]),
+            ("NY", &[doc_char_index(1, 0, 0)][..]),
             ("subway", &[doc_char_index(1, 1, 1)][..]),
         ]);
 
-        store.add_synonym("NY",  SetBuf::from_dirty(vec!["NYC", "new york", "new york city"]));
-        store.add_synonym("NYC", SetBuf::from_dirty(vec!["NY",  "new york", "new york city"]));
+        store.add_synonym(
+            "NY",
+            SetBuf::from_dirty(vec!["NYC", "new york", "new york city"]),
+        );
+        store.add_synonym(
+            "NYC",
+            SetBuf::from_dirty(vec!["NY", "new york", "new york city"]),
+        );
 
         let env = &store.database.env;
         let reader = env.read_txn().unwrap();
@@ -1056,20 +1094,18 @@ mod tests {
     #[test]
     fn unique_to_multiword_synonyms_words_proximity() {
         let mut store = TempDatabase::from_iter(vec![
-            ("new",    &[doc_char_index(0, 0, 0)][..]),
-            ("york",   &[doc_char_index(0, 1, 1)][..]),
-            ("city",   &[doc_char_index(0, 2, 2)][..]),
+            ("new", &[doc_char_index(0, 0, 0)][..]),
+            ("york", &[doc_char_index(0, 1, 1)][..]),
+            ("city", &[doc_char_index(0, 2, 2)][..]),
             ("subway", &[doc_char_index(0, 3, 3)][..]),
-
-            ("york",   &[doc_char_index(1, 0, 0)][..]),
-            ("new",    &[doc_char_index(1, 1, 1)][..]),
+            ("york", &[doc_char_index(1, 0, 0)][..]),
+            ("new", &[doc_char_index(1, 1, 1)][..]),
             ("subway", &[doc_char_index(1, 2, 2)][..]),
-
-            ("NY",     &[doc_char_index(2, 0, 0)][..]),
+            ("NY", &[doc_char_index(2, 0, 0)][..]),
             ("subway", &[doc_char_index(2, 1, 1)][..]),
         ]);
 
-        store.add_synonym("NY",  SetBuf::from_dirty(vec!["york new"]));
+        store.add_synonym("NY", SetBuf::from_dirty(vec!["york new"]));
 
         let env = &store.database.env;
         let reader = env.read_txn().unwrap();
@@ -1120,11 +1156,10 @@ mod tests {
     #[test]
     fn unique_to_multiword_synonyms_cumulative_word_index() {
         let mut store = TempDatabase::from_iter(vec![
-            ("NY",     &[doc_char_index(0, 0, 0)][..]),
+            ("NY", &[doc_char_index(0, 0, 0)][..]),
             ("subway", &[doc_char_index(0, 1, 1)][..]),
-
-            ("new",    &[doc_char_index(1, 0, 0)][..]),
-            ("york",   &[doc_char_index(1, 1, 1)][..]),
+            ("new", &[doc_char_index(1, 0, 0)][..]),
+            ("york", &[doc_char_index(1, 1, 1)][..]),
             ("subway", &[doc_char_index(1, 2, 2)][..]),
         ]);
 
@@ -1175,20 +1210,25 @@ mod tests {
     /// Unique word has multi-word synonyms
     fn harder_unique_to_multiword_synonyms_one() {
         let mut store = TempDatabase::from_iter(vec![
-            ("new",     &[doc_char_index(0, 0, 0)][..]),
-            ("york",    &[doc_char_index(0, 1, 1)][..]),
-            ("city",    &[doc_char_index(0, 2, 2)][..]),
-            ("yellow",  &[doc_char_index(0, 3, 3)][..]),
-            ("subway",  &[doc_char_index(0, 4, 4)][..]),
-            ("broken",  &[doc_char_index(0, 5, 5)][..]),
-
-            ("NY",      &[doc_char_index(1, 0, 0)][..]),
-            ("blue",    &[doc_char_index(1, 1, 1)][..]),
-            ("subway",  &[doc_char_index(1, 2, 2)][..]),
+            ("new", &[doc_char_index(0, 0, 0)][..]),
+            ("york", &[doc_char_index(0, 1, 1)][..]),
+            ("city", &[doc_char_index(0, 2, 2)][..]),
+            ("yellow", &[doc_char_index(0, 3, 3)][..]),
+            ("subway", &[doc_char_index(0, 4, 4)][..]),
+            ("broken", &[doc_char_index(0, 5, 5)][..]),
+            ("NY", &[doc_char_index(1, 0, 0)][..]),
+            ("blue", &[doc_char_index(1, 1, 1)][..]),
+            ("subway", &[doc_char_index(1, 2, 2)][..]),
         ]);
 
-        store.add_synonym("NY",  SetBuf::from_dirty(vec!["NYC", "new york", "new york city"]));
-        store.add_synonym("NYC", SetBuf::from_dirty(vec!["NY",  "new york", "new york city"]));
+        store.add_synonym(
+            "NY",
+            SetBuf::from_dirty(vec!["NYC", "new york", "new york city"]),
+        );
+        store.add_synonym(
+            "NYC",
+            SetBuf::from_dirty(vec!["NY", "new york", "new york city"]),
+        );
 
         let env = &store.database.env;
         let reader = env.read_txn().unwrap();
@@ -1249,21 +1289,26 @@ mod tests {
     /// Unique word has multi-word synonyms
     fn even_harder_unique_to_multiword_synonyms() {
         let mut store = TempDatabase::from_iter(vec![
-            ("new",         &[doc_char_index(0, 0, 0)][..]),
-            ("york",        &[doc_char_index(0, 1, 1)][..]),
-            ("city",        &[doc_char_index(0, 2, 2)][..]),
-            ("yellow",      &[doc_char_index(0, 3, 3)][..]),
+            ("new", &[doc_char_index(0, 0, 0)][..]),
+            ("york", &[doc_char_index(0, 1, 1)][..]),
+            ("city", &[doc_char_index(0, 2, 2)][..]),
+            ("yellow", &[doc_char_index(0, 3, 3)][..]),
             ("underground", &[doc_char_index(0, 4, 4)][..]),
-            ("train",       &[doc_char_index(0, 5, 5)][..]),
-            ("broken",      &[doc_char_index(0, 6, 6)][..]),
-
-            ("NY",      &[doc_char_index(1, 0, 0)][..]),
-            ("blue",    &[doc_char_index(1, 1, 1)][..]),
-            ("subway",  &[doc_char_index(1, 2, 2)][..]),
+            ("train", &[doc_char_index(0, 5, 5)][..]),
+            ("broken", &[doc_char_index(0, 6, 6)][..]),
+            ("NY", &[doc_char_index(1, 0, 0)][..]),
+            ("blue", &[doc_char_index(1, 1, 1)][..]),
+            ("subway", &[doc_char_index(1, 2, 2)][..]),
         ]);
 
-        store.add_synonym("NY",  SetBuf::from_dirty(vec!["NYC", "new york", "new york city"]));
-        store.add_synonym("NYC", SetBuf::from_dirty(vec!["NY",  "new york", "new york city"]));
+        store.add_synonym(
+            "NY",
+            SetBuf::from_dirty(vec!["NYC", "new york", "new york city"]),
+        );
+        store.add_synonym(
+            "NYC",
+            SetBuf::from_dirty(vec!["NY", "new york", "new york city"]),
+        );
         store.add_synonym("subway", SetBuf::from_dirty(vec!["underground train"]));
 
         let env = &store.database.env;
@@ -1330,30 +1375,36 @@ mod tests {
     /// Multi-word has multi-word synonyms
     fn multiword_to_multiword_synonyms() {
         let mut store = TempDatabase::from_iter(vec![
-            ("NY",      &[doc_char_index(0, 0, 0)][..]),
-            ("subway",  &[doc_char_index(0, 1, 1)][..]),
-
-            ("NYC",     &[doc_char_index(1, 0, 0)][..]),
-            ("blue",    &[doc_char_index(1, 1, 1)][..]),
-            ("subway",  &[doc_char_index(1, 2, 2)][..]),
-            ("broken",  &[doc_char_index(1, 3, 3)][..]),
-
-            ("new",         &[doc_char_index(2, 0, 0)][..]),
-            ("york",        &[doc_char_index(2, 1, 1)][..]),
+            ("NY", &[doc_char_index(0, 0, 0)][..]),
+            ("subway", &[doc_char_index(0, 1, 1)][..]),
+            ("NYC", &[doc_char_index(1, 0, 0)][..]),
+            ("blue", &[doc_char_index(1, 1, 1)][..]),
+            ("subway", &[doc_char_index(1, 2, 2)][..]),
+            ("broken", &[doc_char_index(1, 3, 3)][..]),
+            ("new", &[doc_char_index(2, 0, 0)][..]),
+            ("york", &[doc_char_index(2, 1, 1)][..]),
             ("underground", &[doc_char_index(2, 2, 2)][..]),
-            ("train",       &[doc_char_index(2, 3, 3)][..]),
-            ("broken",      &[doc_char_index(2, 4, 4)][..]),
+            ("train", &[doc_char_index(2, 3, 3)][..]),
+            ("broken", &[doc_char_index(2, 4, 4)][..]),
         ]);
 
-        store.add_synonym("new york", SetBuf::from_dirty(vec![          "NYC", "NY", "new york city" ]));
-        store.add_synonym("new york city", SetBuf::from_dirty(vec![     "NYC", "NY", "new york"      ]));
-        store.add_synonym("underground train", SetBuf::from_dirty(vec![ "subway"                     ]));
+        store.add_synonym(
+            "new york",
+            SetBuf::from_dirty(vec!["NYC", "NY", "new york city"]),
+        );
+        store.add_synonym(
+            "new york city",
+            SetBuf::from_dirty(vec!["NYC", "NY", "new york"]),
+        );
+        store.add_synonym("underground train", SetBuf::from_dirty(vec!["subway"]));
 
         let env = &store.database.env;
         let reader = env.read_txn().unwrap();
 
         let builder = store.query_builder();
-        let results = builder.query(&reader, "new york underground train broken", 0..20).unwrap();
+        let results = builder
+            .query(&reader, "new york underground train broken", 0..20)
+            .unwrap();
         let mut iter = results.into_iter();
 
         assert_matches!(iter.next(), Some(Document { id: DocumentId(2), matches, .. }) => {
@@ -1390,7 +1441,9 @@ mod tests {
         assert_matches!(iter.next(), None);
 
         let builder = store.query_builder();
-        let results = builder.query(&reader, "new york city underground train broken", 0..20).unwrap();
+        let results = builder
+            .query(&reader, "new york city underground train broken", 0..20)
+            .unwrap();
         let mut iter = results.into_iter();
 
         assert_matches!(iter.next(), Some(Document { id: DocumentId(2), matches, .. }) => {
@@ -1436,14 +1489,14 @@ mod tests {
     #[test]
     fn intercrossed_multiword_synonyms() {
         let mut store = TempDatabase::from_iter(vec![
-            ("new",   &[doc_index(0, 0)][..]),
-            ("york",  &[doc_index(0, 1)][..]),
-            ("big",   &[doc_index(0, 2)][..]),
-            ("city",  &[doc_index(0, 3)][..]),
+            ("new", &[doc_index(0, 0)][..]),
+            ("york", &[doc_index(0, 1)][..]),
+            ("big", &[doc_index(0, 2)][..]),
+            ("city", &[doc_index(0, 3)][..]),
         ]);
 
-        store.add_synonym("new york", SetBuf::from_dirty(vec![      "new york city" ]));
-        store.add_synonym("new york city", SetBuf::from_dirty(vec![ "new york"      ]));
+        store.add_synonym("new york", SetBuf::from_dirty(vec!["new york city"]));
+        store.add_synonym("new york city", SetBuf::from_dirty(vec!["new york"]));
 
         let env = &store.database.env;
         let reader = env.read_txn().unwrap();
@@ -1469,16 +1522,14 @@ mod tests {
         assert_matches!(iter.next(), None);
 
         let mut store = TempDatabase::from_iter(vec![
-            ("NY",     &[doc_index(0, 0)][..]),
-            ("city",   &[doc_index(0, 1)][..]),
+            ("NY", &[doc_index(0, 0)][..]),
+            ("city", &[doc_index(0, 1)][..]),
             ("subway", &[doc_index(0, 2)][..]),
-
-            ("NY",     &[doc_index(1, 0)][..]),
+            ("NY", &[doc_index(1, 0)][..]),
             ("subway", &[doc_index(1, 1)][..]),
-
-            ("NY",     &[doc_index(2, 0)][..]),
-            ("york",   &[doc_index(2, 1)][..]),
-            ("city",   &[doc_index(2, 2)][..]),
+            ("NY", &[doc_index(2, 0)][..]),
+            ("york", &[doc_index(2, 1)][..]),
+            ("city", &[doc_index(2, 2)][..]),
             ("subway", &[doc_index(2, 3)][..]),
         ]);
 
@@ -1525,20 +1576,22 @@ mod tests {
     #[test]
     fn cumulative_word_indices() {
         let mut store = TempDatabase::from_iter(vec![
-            ("NYC",    &[doc_index(0, 0)][..]),
-            ("long",   &[doc_index(0, 1)][..]),
+            ("NYC", &[doc_index(0, 0)][..]),
+            ("long", &[doc_index(0, 1)][..]),
             ("subway", &[doc_index(0, 2)][..]),
-            ("cool",   &[doc_index(0, 3)][..]),
+            ("cool", &[doc_index(0, 3)][..]),
         ]);
 
         store.add_synonym("new york city", SetBuf::from_dirty(vec!["NYC"]));
-        store.add_synonym("subway",        SetBuf::from_dirty(vec!["underground train"]));
+        store.add_synonym("subway", SetBuf::from_dirty(vec!["underground train"]));
 
         let env = &store.database.env;
         let reader = env.read_txn().unwrap();
 
         let builder = store.query_builder();
-        let results = builder.query(&reader, "new york city long subway cool ", 0..20).unwrap();
+        let results = builder
+            .query(&reader, "new york city long subway cool ", 0..20)
+            .unwrap();
         let mut iter = results.into_iter();
 
         assert_matches!(iter.next(), Some(Document { id: DocumentId(0), matches, .. }) => {
@@ -1560,8 +1613,7 @@ mod tests {
         let mut store = TempDatabase::from_iter(vec![
             ("telephone", &[doc_index(0, 0)][..]), // meilidb indexes the unidecoded
             ("téléphone", &[doc_index(0, 0)][..]), // and the original words on the same DocIndex
-
-            ("iphone",    &[doc_index(1, 0)][..]),
+            ("iphone", &[doc_index(1, 0)][..]),
         ]);
 
         store.add_synonym("téléphone", SetBuf::from_dirty(vec!["iphone"]));
@@ -1624,8 +1676,8 @@ mod tests {
     #[test]
     fn simple_concatenation() {
         let store = TempDatabase::from_iter(vec![
-            ("iphone",  &[doc_index(0, 0)][..]),
-            ("case",    &[doc_index(0, 1)][..]),
+            ("iphone", &[doc_index(0, 0)][..]),
+            ("case", &[doc_index(0, 1)][..]),
         ]);
 
         let env = &store.database.env;
diff --git a/meilidb-core/src/ranked_map.rs b/meilidb-core/src/ranked_map.rs
index d5bd15873..da34e2ff0 100644
--- a/meilidb-core/src/ranked_map.rs
+++ b/meilidb-core/src/ranked_map.rs
@@ -2,12 +2,11 @@ use std::io::{Read, Write};
 
 use hashbrown::HashMap;
 use meilidb_schema::SchemaAttr;
-use serde::{Serialize, Deserialize};
+use serde::{Deserialize, Serialize};
 
 use crate::{DocumentId, Number};
 
-#[derive(Debug, Default, Clone, PartialEq, Eq)]
-#[derive(Serialize, Deserialize)]
+#[derive(Debug, Default, Clone, PartialEq, Eq, Serialize, Deserialize)]
 #[serde(transparent)]
 pub struct RankedMap(HashMap<(DocumentId, SchemaAttr), Number>);
 
diff --git a/meilidb-core/src/raw_document.rs b/meilidb-core/src/raw_document.rs
index 16cc9edda..ccdaa0b2f 100644
--- a/meilidb-core/src/raw_document.rs
+++ b/meilidb-core/src/raw_document.rs
@@ -1,11 +1,11 @@
-use std::sync::Arc;
 use std::fmt;
+use std::sync::Arc;
 
 use meilidb_schema::SchemaAttr;
 use sdset::SetBuf;
 use slice_group_by::GroupBy;
 
-use crate::{TmpMatch, DocumentId, Highlight};
+use crate::{DocumentId, Highlight, TmpMatch};
 
 #[derive(Clone)]
 pub struct RawDocument {
@@ -20,7 +20,13 @@ impl RawDocument {
         let r = self.matches.range;
         // it is safe because construction/modifications
         // can only be done in this module
-        unsafe { &self.matches.matches.query_index.get_unchecked(r.start..r.end) }
+        unsafe {
+            &self
+                .matches
+                .matches
+                .query_index
+                .get_unchecked(r.start..r.end)
+        }
     }
 
     pub fn distance(&self) -> &[u8] {
@@ -41,7 +47,13 @@ impl RawDocument {
         let r = self.matches.range;
         // it is safe because construction/modifications
         // can only be done in this module
-        unsafe { &self.matches.matches.word_index.get_unchecked(r.start..r.end) }
+        unsafe {
+            &self
+                .matches
+                .matches
+                .word_index
+                .get_unchecked(r.start..r.end)
+        }
     }
 
     pub fn is_exact(&self) -> &[bool] {
@@ -55,12 +67,32 @@ impl RawDocument {
 impl fmt::Debug for RawDocument {
     fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
         f.write_str("RawDocument {\r\n")?;
-        f.write_fmt(format_args!("{:>15}: {:?},\r\n",    "id",          self.id))?;
-        f.write_fmt(format_args!("{:>15}: {:^5?},\r\n",  "query_index", self.query_index()))?;
-        f.write_fmt(format_args!("{:>15}: {:^5?},\r\n",  "distance",    self.distance()))?;
-        f.write_fmt(format_args!("{:>15}: {:^5?},\r\n",  "attribute",   self.attribute()))?;
-        f.write_fmt(format_args!("{:>15}: {:^5?},\r\n",  "word_index",  self.word_index()))?;
-        f.write_fmt(format_args!("{:>15}: {:^5?},\r\n",  "is_exact",    self.is_exact()))?;
+        f.write_fmt(format_args!("{:>15}: {:?},\r\n", "id", self.id))?;
+        f.write_fmt(format_args!(
+            "{:>15}: {:^5?},\r\n",
+            "query_index",
+            self.query_index()
+        ))?;
+        f.write_fmt(format_args!(
+            "{:>15}: {:^5?},\r\n",
+            "distance",
+            self.distance()
+        ))?;
+        f.write_fmt(format_args!(
+            "{:>15}: {:^5?},\r\n",
+            "attribute",
+            self.attribute()
+        ))?;
+        f.write_fmt(format_args!(
+            "{:>15}: {:^5?},\r\n",
+            "word_index",
+            self.word_index()
+        ))?;
+        f.write_fmt(format_args!(
+            "{:>15}: {:^5?},\r\n",
+            "is_exact",
+            self.is_exact()
+        ))?;
         f.write_str("}")?;
         Ok(())
     }
@@ -70,8 +102,7 @@ pub fn raw_documents_from(
     matches: SetBuf<(DocumentId, TmpMatch)>,
     highlights: SetBuf<(DocumentId, Highlight)>,
     fields_counts: SetBuf<(DocumentId, SchemaAttr, u64)>,
-) -> Vec<RawDocument>
-{
+) -> Vec<RawDocument> {
     let mut docs_ranges: Vec<(_, Range, _, _)> = Vec::new();
     let mut matches2 = Matches::with_capacity(matches.len());
 
@@ -94,10 +125,21 @@ pub fn raw_documents_from(
     }
 
     let matches = Arc::new(matches2);
-    docs_ranges.into_iter().map(|(id, range, highlights, fields_counts)| {
-        let matches = SharedMatches { range, matches: matches.clone() };
-        RawDocument { id, matches, highlights, fields_counts }
-    }).collect()
+    docs_ranges
+        .into_iter()
+        .map(|(id, range, highlights, fields_counts)| {
+            let matches = SharedMatches {
+                range,
+                matches: matches.clone(),
+            };
+            RawDocument {
+                id,
+                matches,
+                highlights,
+                fields_counts,
+            }
+        })
+        .collect()
 }
 
 #[derive(Debug, Copy, Clone)]
diff --git a/meilidb-core/src/raw_indexer.rs b/meilidb-core/src/raw_indexer.rs
index 980b622f7..615855187 100644
--- a/meilidb-core/src/raw_indexer.rs
+++ b/meilidb-core/src/raw_indexer.rs
@@ -1,10 +1,10 @@
 use std::collections::{BTreeMap, HashMap};
 use std::convert::TryFrom;
 
+use crate::{DocIndex, DocumentId};
 use deunicode::deunicode_with_tofu;
-use crate::{DocumentId, DocIndex};
 use meilidb_schema::SchemaAttr;
-use meilidb_tokenizer::{is_cjk, Tokenizer, SeqTokenizer, Token};
+use meilidb_tokenizer::{is_cjk, SeqTokenizer, Token, Tokenizer};
 use sdset::SetBuf;
 
 type Word = Vec<u8>; // TODO make it be a SmallVec
@@ -60,7 +60,9 @@ impl RawIndexer {
                     &mut self.docs_words,
                 );
 
-                if !must_continue { break }
+                if !must_continue {
+                    break;
+                }
 
                 number_of_words += 1;
             }
@@ -70,8 +72,9 @@ impl RawIndexer {
     }
 
     pub fn index_text_seq<'a, I, IT>(&mut self, id: DocumentId, attr: SchemaAttr, iter: I)
-    where I: IntoIterator<Item=&'a str, IntoIter=IT>,
-          IT: Iterator<Item = &'a str> + Clone,
+    where
+        I: IntoIterator<Item = &'a str, IntoIter = IT>,
+        IT: Iterator<Item = &'a str> + Clone,
     {
         // TODO serialize this to one call to the SeqTokenizer loop
 
@@ -88,14 +91,25 @@ impl RawIndexer {
                 &mut self.docs_words,
             );
 
-            if !must_continue { break }
+            if !must_continue {
+                break;
+            }
         }
 
-        let deunicoded: Vec<_> = lowercased.into_iter().map(|lowercase_text| {
-            if lowercase_text.contains(is_cjk) { return lowercase_text }
-            let deunicoded = deunicode_with_tofu(&lowercase_text, "");
-            if lowercase_text != deunicoded { deunicoded } else { lowercase_text }
-        }).collect();
+        let deunicoded: Vec<_> = lowercased
+            .into_iter()
+            .map(|lowercase_text| {
+                if lowercase_text.contains(is_cjk) {
+                    return lowercase_text;
+                }
+                let deunicoded = deunicode_with_tofu(&lowercase_text, "");
+                if lowercase_text != deunicoded {
+                    deunicoded
+                } else {
+                    lowercase_text
+                }
+            })
+            .collect();
         let iter = deunicoded.iter().map(|t| t.as_str());
 
         for token in SeqTokenizer::new(iter) {
@@ -108,17 +122,21 @@ impl RawIndexer {
                 &mut self.docs_words,
             );
 
-            if !must_continue { break }
+            if !must_continue {
+                break;
+            }
         }
     }
 
     pub fn build(self) -> Indexed {
-        let words_doc_indexes = self.words_doc_indexes
+        let words_doc_indexes = self
+            .words_doc_indexes
             .into_iter()
             .map(|(word, indexes)| (word, SetBuf::from_dirty(indexes)))
             .collect();
 
-        let docs_words = self.docs_words
+        let docs_words = self
+            .docs_words
             .into_iter()
             .map(|(id, mut words)| {
                 words.sort_unstable();
@@ -127,7 +145,10 @@ impl RawIndexer {
             })
             .collect();
 
-        Indexed { words_doc_indexes, docs_words }
+        Indexed {
+            words_doc_indexes,
+            docs_words,
+        }
     }
 }
 
@@ -138,16 +159,20 @@ fn index_token(
     word_limit: usize,
     words_doc_indexes: &mut BTreeMap<Word, Vec<DocIndex>>,
     docs_words: &mut HashMap<DocumentId, Vec<Word>>,
-) -> bool
-{
-    if token.word_index >= word_limit { return false }
+) -> bool {
+    if token.word_index >= word_limit {
+        return false;
+    }
 
     match token_to_docindex(id, attr, token) {
         Some(docindex) => {
             let word = Vec::from(token.word);
-            words_doc_indexes.entry(word.clone()).or_insert_with(Vec::new).push(docindex);
+            words_doc_indexes
+                .entry(word.clone())
+                .or_insert_with(Vec::new)
+                .push(docindex);
             docs_words.entry(id).or_insert_with(Vec::new).push(word);
-        },
+        }
         None => return false,
     }
 
@@ -183,7 +208,9 @@ mod tests {
         let text = "Zut, l’aspirateur, j’ai oublié de l’éteindre !";
         indexer.index_text(docid, attr, text);
 
-        let Indexed { words_doc_indexes, .. } = indexer.build();
+        let Indexed {
+            words_doc_indexes, ..
+        } = indexer.build();
 
         assert!(words_doc_indexes.get(&b"l"[..]).is_some());
         assert!(words_doc_indexes.get(&b"aspirateur"[..]).is_some());
@@ -191,7 +218,9 @@ mod tests {
         assert!(words_doc_indexes.get(&b"eteindre"[..]).is_some());
 
         // with the ugly apostrophe...
-        assert!(words_doc_indexes.get(&"l’éteindre".to_owned().into_bytes()).is_some());
+        assert!(words_doc_indexes
+            .get(&"l’éteindre".to_owned().into_bytes())
+            .is_some());
     }
 
     #[test]
@@ -203,7 +232,9 @@ mod tests {
         let text = vec!["Zut, l’aspirateur, j’ai oublié de l’éteindre !"];
         indexer.index_text_seq(docid, attr, text);
 
-        let Indexed { words_doc_indexes, .. } = indexer.build();
+        let Indexed {
+            words_doc_indexes, ..
+        } = indexer.build();
 
         assert!(words_doc_indexes.get(&b"l"[..]).is_some());
         assert!(words_doc_indexes.get(&b"aspirateur"[..]).is_some());
@@ -211,6 +242,8 @@ mod tests {
         assert!(words_doc_indexes.get(&b"eteindre"[..]).is_some());
 
         // with the ugly apostrophe...
-        assert!(words_doc_indexes.get(&"l’éteindre".to_owned().into_bytes()).is_some());
+        assert!(words_doc_indexes
+            .get(&"l’éteindre".to_owned().into_bytes())
+            .is_some());
     }
 }
diff --git a/meilidb-core/src/reordered_attrs.rs b/meilidb-core/src/reordered_attrs.rs
index ed11045ab..b2f9f1d6c 100644
--- a/meilidb-core/src/reordered_attrs.rs
+++ b/meilidb-core/src/reordered_attrs.rs
@@ -6,7 +6,10 @@ pub struct ReorderedAttrs {
 
 impl ReorderedAttrs {
     pub fn new() -> ReorderedAttrs {
-        ReorderedAttrs { count: 0, reorders: Vec::new() }
+        ReorderedAttrs {
+            count: 0,
+            reorders: Vec::new(),
+        }
     }
 
     pub fn insert_attribute(&mut self, attribute: u16) {
diff --git a/meilidb-core/src/serde/convert_to_number.rs b/meilidb-core/src/serde/convert_to_number.rs
index aec22730a..a67e01692 100644
--- a/meilidb-core/src/serde/convert_to_number.rs
+++ b/meilidb-core/src/serde/convert_to_number.rs
@@ -77,13 +77,18 @@ impl ser::Serializer for ConvertToNumber {
     }
 
     fn serialize_none(self) -> Result<Self::Ok, Self::Error> {
-        Err(SerializerError::UnrankableType { type_name: "Option" })
+        Err(SerializerError::UnrankableType {
+            type_name: "Option",
+        })
     }
 
     fn serialize_some<T: ?Sized>(self, _value: &T) -> Result<Self::Ok, Self::Error>
-    where T: Serialize,
+    where
+        T: Serialize,
     {
-        Err(SerializerError::UnrankableType { type_name: "Option" })
+        Err(SerializerError::UnrankableType {
+            type_name: "Option",
+        })
     }
 
     fn serialize_unit(self) -> Result<Self::Ok, Self::Error> {
@@ -91,25 +96,29 @@ impl ser::Serializer for ConvertToNumber {
     }
 
     fn serialize_unit_struct(self, _name: &'static str) -> Result<Self::Ok, Self::Error> {
-        Err(SerializerError::UnrankableType { type_name: "unit struct" })
+        Err(SerializerError::UnrankableType {
+            type_name: "unit struct",
+        })
     }
 
     fn serialize_unit_variant(
         self,
         _name: &'static str,
         _variant_index: u32,
-        _variant: &'static str
-    ) -> Result<Self::Ok, Self::Error>
-    {
-        Err(SerializerError::UnrankableType { type_name: "unit variant" })
+        _variant: &'static str,
+    ) -> Result<Self::Ok, Self::Error> {
+        Err(SerializerError::UnrankableType {
+            type_name: "unit variant",
+        })
     }
 
     fn serialize_newtype_struct<T: ?Sized>(
         self,
         _name: &'static str,
-        value: &T
+        value: &T,
     ) -> Result<Self::Ok, Self::Error>
-    where T: Serialize,
+    where
+        T: Serialize,
     {
         value.serialize(self)
     }
@@ -119,15 +128,20 @@ impl ser::Serializer for ConvertToNumber {
         _name: &'static str,
         _variant_index: u32,
         _variant: &'static str,
-        _value: &T
+        _value: &T,
     ) -> Result<Self::Ok, Self::Error>
-    where T: Serialize,
+    where
+        T: Serialize,
     {
-        Err(SerializerError::UnrankableType { type_name: "newtype variant" })
+        Err(SerializerError::UnrankableType {
+            type_name: "newtype variant",
+        })
     }
 
     fn serialize_seq(self, _len: Option<usize>) -> Result<Self::SerializeSeq, Self::Error> {
-        Err(SerializerError::UnrankableType { type_name: "sequence" })
+        Err(SerializerError::UnrankableType {
+            type_name: "sequence",
+        })
     }
 
     fn serialize_tuple(self, _len: usize) -> Result<Self::SerializeTuple, Self::Error> {
@@ -137,10 +151,11 @@ impl ser::Serializer for ConvertToNumber {
     fn serialize_tuple_struct(
         self,
         _name: &'static str,
-        _len: usize
-    ) -> Result<Self::SerializeTupleStruct, Self::Error>
-    {
-        Err(SerializerError::UnrankableType { type_name: "tuple struct" })
+        _len: usize,
+    ) -> Result<Self::SerializeTupleStruct, Self::Error> {
+        Err(SerializerError::UnrankableType {
+            type_name: "tuple struct",
+        })
     }
 
     fn serialize_tuple_variant(
@@ -148,10 +163,11 @@ impl ser::Serializer for ConvertToNumber {
         _name: &'static str,
         _variant_index: u32,
         _variant: &'static str,
-        _len: usize
-    ) -> Result<Self::SerializeTupleVariant, Self::Error>
-    {
-        Err(SerializerError::UnrankableType { type_name: "tuple variant" })
+        _len: usize,
+    ) -> Result<Self::SerializeTupleVariant, Self::Error> {
+        Err(SerializerError::UnrankableType {
+            type_name: "tuple variant",
+        })
     }
 
     fn serialize_map(self, _len: Option<usize>) -> Result<Self::SerializeMap, Self::Error> {
@@ -161,10 +177,11 @@ impl ser::Serializer for ConvertToNumber {
     fn serialize_struct(
         self,
         _name: &'static str,
-        _len: usize
-    ) -> Result<Self::SerializeStruct, Self::Error>
-    {
-        Err(SerializerError::UnrankableType { type_name: "struct" })
+        _len: usize,
+    ) -> Result<Self::SerializeStruct, Self::Error> {
+        Err(SerializerError::UnrankableType {
+            type_name: "struct",
+        })
     }
 
     fn serialize_struct_variant(
@@ -172,9 +189,10 @@ impl ser::Serializer for ConvertToNumber {
         _name: &'static str,
         _variant_index: u32,
         _variant: &'static str,
-        _len: usize
-    ) -> Result<Self::SerializeStructVariant, Self::Error>
-    {
-        Err(SerializerError::UnrankableType { type_name: "struct variant" })
+        _len: usize,
+    ) -> Result<Self::SerializeStructVariant, Self::Error> {
+        Err(SerializerError::UnrankableType {
+            type_name: "struct variant",
+        })
     }
 }
diff --git a/meilidb-core/src/serde/convert_to_string.rs b/meilidb-core/src/serde/convert_to_string.rs
index cd109f534..2f1fe0ca1 100644
--- a/meilidb-core/src/serde/convert_to_string.rs
+++ b/meilidb-core/src/serde/convert_to_string.rs
@@ -1,5 +1,5 @@
-use serde::Serialize;
 use serde::ser;
+use serde::Serialize;
 
 use super::SerializerError;
 
@@ -17,7 +17,9 @@ impl ser::Serializer for ConvertToString {
     type SerializeStructVariant = ser::Impossible<Self::Ok, Self::Error>;
 
     fn serialize_bool(self, _value: bool) -> Result<Self::Ok, Self::Error> {
-        Err(SerializerError::UnserializableType { type_name: "boolean" })
+        Err(SerializerError::UnserializableType {
+            type_name: "boolean",
+        })
     }
 
     fn serialize_char(self, value: char) -> Result<Self::Ok, Self::Error> {
@@ -73,13 +75,18 @@ impl ser::Serializer for ConvertToString {
     }
 
     fn serialize_none(self) -> Result<Self::Ok, Self::Error> {
-        Err(SerializerError::UnserializableType { type_name: "Option" })
+        Err(SerializerError::UnserializableType {
+            type_name: "Option",
+        })
     }
 
     fn serialize_some<T: ?Sized>(self, _value: &T) -> Result<Self::Ok, Self::Error>
-    where T: Serialize,
+    where
+        T: Serialize,
     {
-        Err(SerializerError::UnserializableType { type_name: "Option" })
+        Err(SerializerError::UnserializableType {
+            type_name: "Option",
+        })
     }
 
     fn serialize_unit(self) -> Result<Self::Ok, Self::Error> {
@@ -87,25 +94,29 @@ impl ser::Serializer for ConvertToString {
     }
 
     fn serialize_unit_struct(self, _name: &'static str) -> Result<Self::Ok, Self::Error> {
-        Err(SerializerError::UnserializableType { type_name: "unit struct" })
+        Err(SerializerError::UnserializableType {
+            type_name: "unit struct",
+        })
     }
 
     fn serialize_unit_variant(
         self,
         _name: &'static str,
         _variant_index: u32,
-        _variant: &'static str
-    ) -> Result<Self::Ok, Self::Error>
-    {
-        Err(SerializerError::UnserializableType { type_name: "unit variant" })
+        _variant: &'static str,
+    ) -> Result<Self::Ok, Self::Error> {
+        Err(SerializerError::UnserializableType {
+            type_name: "unit variant",
+        })
     }
 
     fn serialize_newtype_struct<T: ?Sized>(
         self,
         _name: &'static str,
-        value: &T
+        value: &T,
     ) -> Result<Self::Ok, Self::Error>
-    where T: Serialize,
+    where
+        T: Serialize,
     {
         value.serialize(self)
     }
@@ -115,15 +126,20 @@ impl ser::Serializer for ConvertToString {
         _name: &'static str,
         _variant_index: u32,
         _variant: &'static str,
-        _value: &T
+        _value: &T,
     ) -> Result<Self::Ok, Self::Error>
-    where T: Serialize,
+    where
+        T: Serialize,
     {
-        Err(SerializerError::UnserializableType { type_name: "newtype variant" })
+        Err(SerializerError::UnserializableType {
+            type_name: "newtype variant",
+        })
     }
 
     fn serialize_seq(self, _len: Option<usize>) -> Result<Self::SerializeSeq, Self::Error> {
-        Err(SerializerError::UnserializableType { type_name: "sequence" })
+        Err(SerializerError::UnserializableType {
+            type_name: "sequence",
+        })
     }
 
     fn serialize_tuple(self, _len: usize) -> Result<Self::SerializeTuple, Self::Error> {
@@ -133,10 +149,11 @@ impl ser::Serializer for ConvertToString {
     fn serialize_tuple_struct(
         self,
         _name: &'static str,
-        _len: usize
-    ) -> Result<Self::SerializeTupleStruct, Self::Error>
-    {
-        Err(SerializerError::UnserializableType { type_name: "tuple struct" })
+        _len: usize,
+    ) -> Result<Self::SerializeTupleStruct, Self::Error> {
+        Err(SerializerError::UnserializableType {
+            type_name: "tuple struct",
+        })
     }
 
     fn serialize_tuple_variant(
@@ -144,10 +161,11 @@ impl ser::Serializer for ConvertToString {
         _name: &'static str,
         _variant_index: u32,
         _variant: &'static str,
-        _len: usize
-    ) -> Result<Self::SerializeTupleVariant, Self::Error>
-    {
-        Err(SerializerError::UnserializableType { type_name: "tuple variant" })
+        _len: usize,
+    ) -> Result<Self::SerializeTupleVariant, Self::Error> {
+        Err(SerializerError::UnserializableType {
+            type_name: "tuple variant",
+        })
     }
 
     fn serialize_map(self, _len: Option<usize>) -> Result<Self::SerializeMap, Self::Error> {
@@ -157,10 +175,11 @@ impl ser::Serializer for ConvertToString {
     fn serialize_struct(
         self,
         _name: &'static str,
-        _len: usize
-    ) -> Result<Self::SerializeStruct, Self::Error>
-    {
-        Err(SerializerError::UnserializableType { type_name: "struct" })
+        _len: usize,
+    ) -> Result<Self::SerializeStruct, Self::Error> {
+        Err(SerializerError::UnserializableType {
+            type_name: "struct",
+        })
     }
 
     fn serialize_struct_variant(
@@ -168,9 +187,10 @@ impl ser::Serializer for ConvertToString {
         _name: &'static str,
         _variant_index: u32,
         _variant: &'static str,
-        _len: usize
-    ) -> Result<Self::SerializeStructVariant, Self::Error>
-    {
-        Err(SerializerError::UnserializableType { type_name: "struct variant" })
+        _len: usize,
+    ) -> Result<Self::SerializeStructVariant, Self::Error> {
+        Err(SerializerError::UnserializableType {
+            type_name: "struct variant",
+        })
     }
 }
diff --git a/meilidb-core/src/serde/deserializer.rs b/meilidb-core/src/serde/deserializer.rs
index df5a8b502..3c99b365b 100644
--- a/meilidb-core/src/serde/deserializer.rs
+++ b/meilidb-core/src/serde/deserializer.rs
@@ -1,12 +1,12 @@
 use std::collections::HashSet;
 use std::io::Cursor;
-use std::{fmt, error::Error};
+use std::{error::Error, fmt};
 
 use meilidb_schema::{Schema, SchemaAttr};
-use serde_json::Error as SerdeJsonError;
-use serde_json::Deserializer as SerdeJsonDeserializer;
-use serde_json::de::IoRead as SerdeJsonIoRead;
 use serde::{de, forward_to_deserialize_any};
+use serde_json::de::IoRead as SerdeJsonIoRead;
+use serde_json::Deserializer as SerdeJsonDeserializer;
+use serde_json::Error as SerdeJsonError;
 
 use crate::store::DocumentsFields;
 use crate::DocumentId;
@@ -60,7 +60,8 @@ impl<'de, 'a, 'b> de::Deserializer<'de> for &'b mut Deserializer<'a> {
     type Error = DeserializerError;
 
     fn deserialize_any<V>(self, visitor: V) -> Result<V::Value, Self::Error>
-    where V: de::Visitor<'de>
+    where
+        V: de::Visitor<'de>,
     {
         self.deserialize_map(visitor)
     }
@@ -72,16 +73,21 @@ impl<'de, 'a, 'b> de::Deserializer<'de> for &'b mut Deserializer<'a> {
     }
 
     fn deserialize_map<V>(self, visitor: V) -> Result<V::Value, Self::Error>
-    where V: de::Visitor<'de>
+    where
+        V: de::Visitor<'de>,
     {
         let mut error = None;
 
-        let iter = self.documents_fields
+        let iter = self
+            .documents_fields
             .document_fields(self.reader, self.document_id)?
             .filter_map(|result| {
                 let (attr, value) = match result {
                     Ok(value) => value,
-                    Err(e) => { error = Some(e); return None },
+                    Err(e) => {
+                        error = Some(e);
+                        return None;
+                    }
                 };
 
                 let is_displayed = self.schema.props(attr).is_displayed();
@@ -99,7 +105,9 @@ impl<'de, 'a, 'b> de::Deserializer<'de> for &'b mut Deserializer<'a> {
             });
 
         let map_deserializer = de::value::MapDeserializer::new(iter);
-        let result = visitor.visit_map(map_deserializer).map_err(DeserializerError::from);
+        let result = visitor
+            .visit_map(map_deserializer)
+            .map_err(DeserializerError::from);
 
         match error.take() {
             Some(error) => Err(error.into()),
@@ -122,7 +130,8 @@ impl<'de> de::Deserializer<'de> for Value {
     type Error = SerdeJsonError;
 
     fn deserialize_any<V>(mut self, visitor: V) -> Result<V::Value, Self::Error>
-    where V: de::Visitor<'de>
+    where
+        V: de::Visitor<'de>,
     {
         self.0.deserialize_any(visitor)
     }
diff --git a/meilidb-core/src/serde/extract_document_id.rs b/meilidb-core/src/serde/extract_document_id.rs
index da90101e2..5c2a81d2e 100644
--- a/meilidb-core/src/serde/extract_document_id.rs
+++ b/meilidb-core/src/serde/extract_document_id.rs
@@ -5,13 +5,14 @@ use serde::{ser, Serialize};
 use serde_json::Value;
 use siphasher::sip::SipHasher;
 
-use super::{SerializerError, ConvertToString};
+use super::{ConvertToString, SerializerError};
 
 pub fn extract_document_id<D>(
     identifier: &str,
     document: &D,
 ) -> Result<Option<DocumentId>, SerializerError>
-where D: serde::Serialize,
+where
+    D: serde::Serialize,
 {
     let serializer = ExtractDocumentId { identifier };
     document.serialize(serializer)
@@ -77,13 +78,18 @@ impl<'a> ser::Serializer for ExtractDocumentId<'a> {
     }
 
     fn serialize_none(self) -> Result<Self::Ok, Self::Error> {
-        Err(SerializerError::UnserializableType { type_name: "Option" })
+        Err(SerializerError::UnserializableType {
+            type_name: "Option",
+        })
     }
 
     fn serialize_some<T: ?Sized>(self, _value: &T) -> Result<Self::Ok, Self::Error>
-    where T: Serialize,
+    where
+        T: Serialize,
     {
-        Err(SerializerError::UnserializableType { type_name: "Option" })
+        Err(SerializerError::UnserializableType {
+            type_name: "Option",
+        })
     }
 
     fn serialize_unit(self) -> Result<Self::Ok, Self::Error> {
@@ -91,25 +97,29 @@ impl<'a> ser::Serializer for ExtractDocumentId<'a> {
     }
 
     fn serialize_unit_struct(self, _name: &'static str) -> Result<Self::Ok, Self::Error> {
-        Err(SerializerError::UnserializableType { type_name: "unit struct" })
+        Err(SerializerError::UnserializableType {
+            type_name: "unit struct",
+        })
     }
 
     fn serialize_unit_variant(
         self,
         _name: &'static str,
         _variant_index: u32,
-        _variant: &'static str
-    ) -> Result<Self::Ok, Self::Error>
-    {
-        Err(SerializerError::UnserializableType { type_name: "unit variant" })
+        _variant: &'static str,
+    ) -> Result<Self::Ok, Self::Error> {
+        Err(SerializerError::UnserializableType {
+            type_name: "unit variant",
+        })
     }
 
     fn serialize_newtype_struct<T: ?Sized>(
         self,
         _name: &'static str,
-        value: &T
+        value: &T,
     ) -> Result<Self::Ok, Self::Error>
-    where T: Serialize,
+    where
+        T: Serialize,
     {
         value.serialize(self)
     }
@@ -119,15 +129,20 @@ impl<'a> ser::Serializer for ExtractDocumentId<'a> {
         _name: &'static str,
         _variant_index: u32,
         _variant: &'static str,
-        _value: &T
+        _value: &T,
     ) -> Result<Self::Ok, Self::Error>
-    where T: Serialize,
+    where
+        T: Serialize,
     {
-        Err(SerializerError::UnserializableType { type_name: "newtype variant" })
+        Err(SerializerError::UnserializableType {
+            type_name: "newtype variant",
+        })
     }
 
     fn serialize_seq(self, _len: Option<usize>) -> Result<Self::SerializeSeq, Self::Error> {
-        Err(SerializerError::UnserializableType { type_name: "sequence" })
+        Err(SerializerError::UnserializableType {
+            type_name: "sequence",
+        })
     }
 
     fn serialize_tuple(self, _len: usize) -> Result<Self::SerializeTuple, Self::Error> {
@@ -137,10 +152,11 @@ impl<'a> ser::Serializer for ExtractDocumentId<'a> {
     fn serialize_tuple_struct(
         self,
         _name: &'static str,
-        _len: usize
-    ) -> Result<Self::SerializeTupleStruct, Self::Error>
-    {
-        Err(SerializerError::UnserializableType { type_name: "tuple struct" })
+        _len: usize,
+    ) -> Result<Self::SerializeTupleStruct, Self::Error> {
+        Err(SerializerError::UnserializableType {
+            type_name: "tuple struct",
+        })
     }
 
     fn serialize_tuple_variant(
@@ -148,10 +164,11 @@ impl<'a> ser::Serializer for ExtractDocumentId<'a> {
         _name: &'static str,
         _variant_index: u32,
         _variant: &'static str,
-        _len: usize
-    ) -> Result<Self::SerializeTupleVariant, Self::Error>
-    {
-        Err(SerializerError::UnserializableType { type_name: "tuple variant" })
+        _len: usize,
+    ) -> Result<Self::SerializeTupleVariant, Self::Error> {
+        Err(SerializerError::UnserializableType {
+            type_name: "tuple variant",
+        })
     }
 
     fn serialize_map(self, _len: Option<usize>) -> Result<Self::SerializeMap, Self::Error> {
@@ -167,9 +184,8 @@ impl<'a> ser::Serializer for ExtractDocumentId<'a> {
     fn serialize_struct(
         self,
         _name: &'static str,
-        _len: usize
-    ) -> Result<Self::SerializeStruct, Self::Error>
-    {
+        _len: usize,
+    ) -> Result<Self::SerializeStruct, Self::Error> {
         let serializer = ExtractDocumentIdStructSerializer {
             identifier: self.identifier,
             document_id: None,
@@ -183,10 +199,11 @@ impl<'a> ser::Serializer for ExtractDocumentId<'a> {
         _name: &'static str,
         _variant_index: u32,
         _variant: &'static str,
-        _len: usize
-    ) -> Result<Self::SerializeStructVariant, Self::Error>
-    {
-        Err(SerializerError::UnserializableType { type_name: "struct variant" })
+        _len: usize,
+    ) -> Result<Self::SerializeStructVariant, Self::Error> {
+        Err(SerializerError::UnserializableType {
+            type_name: "struct variant",
+        })
     }
 }
 
@@ -201,7 +218,8 @@ impl<'a> ser::SerializeMap for ExtractDocumentIdMapSerializer<'a> {
     type Error = SerializerError;
 
     fn serialize_key<T: ?Sized>(&mut self, key: &T) -> Result<(), Self::Error>
-    where T: Serialize,
+    where
+        T: Serialize,
     {
         let key = key.serialize(ConvertToString)?;
         self.current_key_name = Some(key);
@@ -209,7 +227,8 @@ impl<'a> ser::SerializeMap for ExtractDocumentIdMapSerializer<'a> {
     }
 
     fn serialize_value<T: ?Sized>(&mut self, value: &T) -> Result<(), Self::Error>
-    where T: Serialize,
+    where
+        T: Serialize,
     {
         let key = self.current_key_name.take().unwrap();
         self.serialize_entry(&key, value)
@@ -218,9 +237,11 @@ impl<'a> ser::SerializeMap for ExtractDocumentIdMapSerializer<'a> {
     fn serialize_entry<K: ?Sized, V: ?Sized>(
         &mut self,
         key: &K,
-        value: &V
+        value: &V,
     ) -> Result<(), Self::Error>
-    where K: Serialize, V: Serialize,
+    where
+        K: Serialize,
+        V: Serialize,
     {
         let key = key.serialize(ConvertToString)?;
 
@@ -252,9 +273,10 @@ impl<'a> ser::SerializeStruct for ExtractDocumentIdStructSerializer<'a> {
     fn serialize_field<T: ?Sized>(
         &mut self,
         key: &'static str,
-        value: &T
+        value: &T,
     ) -> Result<(), Self::Error>
-    where T: Serialize,
+    where
+        T: Serialize,
     {
         if self.identifier == key {
             let value = serde_json::to_string(value).and_then(|s| serde_json::from_str(&s))?;
diff --git a/meilidb-core/src/serde/indexer.rs b/meilidb-core/src/serde/indexer.rs
index 514b97951..04d24a63a 100644
--- a/meilidb-core/src/serde/indexer.rs
+++ b/meilidb-core/src/serde/indexer.rs
@@ -2,9 +2,9 @@ use meilidb_schema::SchemaAttr;
 use serde::ser;
 use serde::Serialize;
 
-use crate::DocumentId;
+use super::{ConvertToString, SerializerError};
 use crate::raw_indexer::RawIndexer;
-use super::{SerializerError, ConvertToString};
+use crate::DocumentId;
 
 pub struct Indexer<'a> {
     pub attribute: SchemaAttr,
@@ -24,7 +24,9 @@ impl<'a> ser::Serializer for Indexer<'a> {
     type SerializeStructVariant = ser::Impossible<Self::Ok, Self::Error>;
 
     fn serialize_bool(self, _value: bool) -> Result<Self::Ok, Self::Error> {
-        Err(SerializerError::UnindexableType { type_name: "boolean" })
+        Err(SerializerError::UnindexableType {
+            type_name: "boolean",
+        })
     }
 
     fn serialize_char(self, value: char) -> Result<Self::Ok, Self::Error> {
@@ -83,7 +85,9 @@ impl<'a> ser::Serializer for Indexer<'a> {
     }
 
     fn serialize_str(self, text: &str) -> Result<Self::Ok, Self::Error> {
-        let number_of_words = self.indexer.index_text(self.document_id, self.attribute, text);
+        let number_of_words = self
+            .indexer
+            .index_text(self.document_id, self.attribute, text);
         Ok(Some(number_of_words))
     }
 
@@ -92,14 +96,19 @@ impl<'a> ser::Serializer for Indexer<'a> {
     }
 
     fn serialize_none(self) -> Result<Self::Ok, Self::Error> {
-        Err(SerializerError::UnindexableType { type_name: "Option" })
+        Err(SerializerError::UnindexableType {
+            type_name: "Option",
+        })
     }
 
     fn serialize_some<T: ?Sized>(self, value: &T) -> Result<Self::Ok, Self::Error>
-    where T: ser::Serialize,
+    where
+        T: ser::Serialize,
     {
         let text = value.serialize(ConvertToString)?;
-        let number_of_words = self.indexer.index_text(self.document_id, self.attribute, &text);
+        let number_of_words = self
+            .indexer
+            .index_text(self.document_id, self.attribute, &text);
         Ok(Some(number_of_words))
     }
 
@@ -108,25 +117,29 @@ impl<'a> ser::Serializer for Indexer<'a> {
     }
 
     fn serialize_unit_struct(self, _name: &'static str) -> Result<Self::Ok, Self::Error> {
-        Err(SerializerError::UnindexableType { type_name: "unit struct" })
+        Err(SerializerError::UnindexableType {
+            type_name: "unit struct",
+        })
     }
 
     fn serialize_unit_variant(
         self,
         _name: &'static str,
         _variant_index: u32,
-        _variant: &'static str
-    ) -> Result<Self::Ok, Self::Error>
-    {
-        Err(SerializerError::UnindexableType { type_name: "unit variant" })
+        _variant: &'static str,
+    ) -> Result<Self::Ok, Self::Error> {
+        Err(SerializerError::UnindexableType {
+            type_name: "unit variant",
+        })
     }
 
     fn serialize_newtype_struct<T: ?Sized>(
         self,
         _name: &'static str,
-        value: &T
+        value: &T,
     ) -> Result<Self::Ok, Self::Error>
-    where T: ser::Serialize,
+    where
+        T: ser::Serialize,
     {
         value.serialize(self)
     }
@@ -136,11 +149,14 @@ impl<'a> ser::Serializer for Indexer<'a> {
         _name: &'static str,
         _variant_index: u32,
         _variant: &'static str,
-        _value: &T
+        _value: &T,
     ) -> Result<Self::Ok, Self::Error>
-    where T: ser::Serialize,
+    where
+        T: ser::Serialize,
     {
-        Err(SerializerError::UnindexableType { type_name: "newtype variant" })
+        Err(SerializerError::UnindexableType {
+            type_name: "newtype variant",
+        })
     }
 
     fn serialize_seq(self, _len: Option<usize>) -> Result<Self::SerializeSeq, Self::Error> {
@@ -168,10 +184,11 @@ impl<'a> ser::Serializer for Indexer<'a> {
     fn serialize_tuple_struct(
         self,
         _name: &'static str,
-        _len: usize
-    ) -> Result<Self::SerializeTupleStruct, Self::Error>
-    {
-        Err(SerializerError::UnindexableType { type_name: "tuple struct" })
+        _len: usize,
+    ) -> Result<Self::SerializeTupleStruct, Self::Error> {
+        Err(SerializerError::UnindexableType {
+            type_name: "tuple struct",
+        })
     }
 
     fn serialize_tuple_variant(
@@ -179,10 +196,11 @@ impl<'a> ser::Serializer for Indexer<'a> {
         _name: &'static str,
         _variant_index: u32,
         _variant: &'static str,
-        _len: usize
-    ) -> Result<Self::SerializeTupleVariant, Self::Error>
-    {
-        Err(SerializerError::UnindexableType { type_name: "tuple variant" })
+        _len: usize,
+    ) -> Result<Self::SerializeTupleVariant, Self::Error> {
+        Err(SerializerError::UnindexableType {
+            type_name: "tuple variant",
+        })
     }
 
     fn serialize_map(self, _len: Option<usize>) -> Result<Self::SerializeMap, Self::Error> {
@@ -199,10 +217,11 @@ impl<'a> ser::Serializer for Indexer<'a> {
     fn serialize_struct(
         self,
         _name: &'static str,
-        _len: usize
-    ) -> Result<Self::SerializeStruct, Self::Error>
-    {
-        Err(SerializerError::UnindexableType { type_name: "struct" })
+        _len: usize,
+    ) -> Result<Self::SerializeStruct, Self::Error> {
+        Err(SerializerError::UnindexableType {
+            type_name: "struct",
+        })
     }
 
     fn serialize_struct_variant(
@@ -210,10 +229,11 @@ impl<'a> ser::Serializer for Indexer<'a> {
         _name: &'static str,
         _variant_index: u32,
         _variant: &'static str,
-        _len: usize
-    ) -> Result<Self::SerializeStructVariant, Self::Error>
-    {
-        Err(SerializerError::UnindexableType { type_name: "struct variant" })
+        _len: usize,
+    ) -> Result<Self::SerializeStructVariant, Self::Error> {
+        Err(SerializerError::UnindexableType {
+            type_name: "struct variant",
+        })
     }
 }
 
@@ -229,7 +249,8 @@ impl<'a> ser::SerializeSeq for SeqIndexer<'a> {
     type Error = SerializerError;
 
     fn serialize_element<T: ?Sized>(&mut self, value: &T) -> Result<(), Self::Error>
-    where T: ser::Serialize
+    where
+        T: ser::Serialize,
     {
         let text = value.serialize(ConvertToString)?;
         self.texts.push(text);
@@ -238,7 +259,8 @@ impl<'a> ser::SerializeSeq for SeqIndexer<'a> {
 
     fn end(self) -> Result<Self::Ok, Self::Error> {
         let texts = self.texts.iter().map(String::as_str);
-        self.indexer.index_text_seq(self.document_id, self.attribute, texts);
+        self.indexer
+            .index_text_seq(self.document_id, self.attribute, texts);
         Ok(None)
     }
 }
@@ -255,7 +277,8 @@ impl<'a> ser::SerializeMap for MapIndexer<'a> {
     type Error = SerializerError;
 
     fn serialize_key<T: ?Sized>(&mut self, key: &T) -> Result<(), Self::Error>
-    where T: ser::Serialize,
+    where
+        T: ser::Serialize,
     {
         let text = key.serialize(ConvertToString)?;
         self.texts.push(text);
@@ -263,7 +286,8 @@ impl<'a> ser::SerializeMap for MapIndexer<'a> {
     }
 
     fn serialize_value<T: ?Sized>(&mut self, value: &T) -> Result<(), Self::Error>
-    where T: ser::Serialize,
+    where
+        T: ser::Serialize,
     {
         let text = value.serialize(ConvertToString)?;
         self.texts.push(text);
@@ -272,7 +296,8 @@ impl<'a> ser::SerializeMap for MapIndexer<'a> {
 
     fn end(self) -> Result<Self::Ok, Self::Error> {
         let texts = self.texts.iter().map(String::as_str);
-        self.indexer.index_text_seq(self.document_id, self.attribute, texts);
+        self.indexer
+            .index_text_seq(self.document_id, self.attribute, texts);
         Ok(None)
     }
 }
@@ -293,7 +318,8 @@ impl<'a> ser::SerializeStruct for StructSerializer<'a> {
         key: &'static str,
         value: &T,
     ) -> Result<(), Self::Error>
-    where T: ser::Serialize,
+    where
+        T: ser::Serialize,
     {
         let key_text = key.to_owned();
         let value_text = value.serialize(ConvertToString)?;
@@ -304,7 +330,8 @@ impl<'a> ser::SerializeStruct for StructSerializer<'a> {
 
     fn end(self) -> Result<Self::Ok, Self::Error> {
         let texts = self.texts.iter().map(String::as_str);
-        self.indexer.index_text_seq(self.document_id, self.attribute, texts);
+        self.indexer
+            .index_text_seq(self.document_id, self.attribute, texts);
         Ok(None)
     }
 }
@@ -321,7 +348,8 @@ impl<'a> ser::SerializeTuple for TupleIndexer<'a> {
     type Error = SerializerError;
 
     fn serialize_element<T: ?Sized>(&mut self, value: &T) -> Result<(), Self::Error>
-    where T: Serialize
+    where
+        T: Serialize,
     {
         let text = value.serialize(ConvertToString)?;
         self.texts.push(text);
@@ -330,7 +358,8 @@ impl<'a> ser::SerializeTuple for TupleIndexer<'a> {
 
     fn end(self) -> Result<Self::Ok, Self::Error> {
         let texts = self.texts.iter().map(String::as_str);
-        self.indexer.index_text_seq(self.document_id, self.attribute, texts);
+        self.indexer
+            .index_text_seq(self.document_id, self.attribute, texts);
         Ok(None)
     }
 }
diff --git a/meilidb-core/src/serde/mod.rs b/meilidb-core/src/serde/mod.rs
index dde014435..47a0926ca 100644
--- a/meilidb-core/src/serde/mod.rs
+++ b/meilidb-core/src/serde/mod.rs
@@ -15,19 +15,19 @@ mod extract_document_id;
 mod indexer;
 mod serializer;
 
-pub use self::deserializer::{Deserializer, DeserializerError};
-pub use self::extract_document_id::{extract_document_id, compute_document_id, value_to_string};
-pub use self::convert_to_string::ConvertToString;
 pub use self::convert_to_number::ConvertToNumber;
+pub use self::convert_to_string::ConvertToString;
+pub use self::deserializer::{Deserializer, DeserializerError};
+pub use self::extract_document_id::{compute_document_id, extract_document_id, value_to_string};
 pub use self::indexer::Indexer;
 pub use self::serializer::Serializer;
 
 use std::collections::BTreeMap;
-use std::{fmt, error::Error};
+use std::{error::Error, fmt};
 
 use meilidb_schema::SchemaAttr;
-use serde_json::Error as SerdeJsonError;
 use serde::ser;
+use serde_json::Error as SerdeJsonError;
 
 use crate::{DocumentId, ParseNumberError};
 
@@ -55,24 +55,24 @@ impl fmt::Display for SerializerError {
         match self {
             SerializerError::DocumentIdNotFound => {
                 f.write_str("serialized document does not have an id according to the schema")
-            },
+            }
             SerializerError::InvalidDocumentIdType => {
                 f.write_str("document identifier can only be of type string or number")
-            },
+            }
             SerializerError::Zlmdb(e) => write!(f, "zlmdb related error: {}", e),
             SerializerError::SerdeJson(e) => write!(f, "serde json error: {}", e),
             SerializerError::ParseNumber(e) => {
                 write!(f, "error while trying to parse a number: {}", e)
-            },
+            }
             SerializerError::UnserializableType { type_name } => {
                 write!(f, "{} is not a serializable type", type_name)
-            },
+            }
             SerializerError::UnindexableType { type_name } => {
                 write!(f, "{} is not an indexable type", type_name)
-            },
+            }
             SerializerError::UnrankableType { type_name } => {
                 write!(f, "{} types can not be used for ranking", type_name)
-            },
+            }
             SerializerError::Custom(s) => f.write_str(s),
         }
     }
diff --git a/meilidb-core/src/serde/serializer.rs b/meilidb-core/src/serde/serializer.rs
index de09c57bc..fa197f620 100644
--- a/meilidb-core/src/serde/serializer.rs
+++ b/meilidb-core/src/serde/serializer.rs
@@ -1,12 +1,12 @@
-use std::collections::HashMap;
 use meilidb_schema::{Schema, SchemaAttr};
 use serde::ser;
+use std::collections::HashMap;
 
-use crate::{DocumentId, RankedMap};
 use crate::raw_indexer::RawIndexer;
 use crate::serde::RamDocumentStore;
+use crate::{DocumentId, RankedMap};
 
-use super::{SerializerError, ConvertToString, ConvertToNumber, Indexer};
+use super::{ConvertToNumber, ConvertToString, Indexer, SerializerError};
 
 pub struct Serializer<'a> {
     pub schema: &'a Schema,
@@ -55,13 +55,18 @@ impl<'a> ser::Serializer for Serializer<'a> {
     }
 
     fn serialize_none(self) -> Result<Self::Ok, Self::Error> {
-        Err(SerializerError::UnserializableType { type_name: "Option" })
+        Err(SerializerError::UnserializableType {
+            type_name: "Option",
+        })
     }
 
     fn serialize_some<T: ?Sized>(self, _value: &T) -> Result<Self::Ok, Self::Error>
-    where T: ser::Serialize,
+    where
+        T: ser::Serialize,
     {
-        Err(SerializerError::UnserializableType { type_name: "Option" })
+        Err(SerializerError::UnserializableType {
+            type_name: "Option",
+        })
     }
 
     fn serialize_unit(self) -> Result<Self::Ok, Self::Error> {
@@ -69,25 +74,29 @@ impl<'a> ser::Serializer for Serializer<'a> {
     }
 
     fn serialize_unit_struct(self, _name: &'static str) -> Result<Self::Ok, Self::Error> {
-        Err(SerializerError::UnserializableType { type_name: "unit struct" })
+        Err(SerializerError::UnserializableType {
+            type_name: "unit struct",
+        })
     }
 
     fn serialize_unit_variant(
         self,
         _name: &'static str,
         _variant_index: u32,
-        _variant: &'static str
-    ) -> Result<Self::Ok, Self::Error>
-    {
-        Err(SerializerError::UnserializableType { type_name: "unit variant" })
+        _variant: &'static str,
+    ) -> Result<Self::Ok, Self::Error> {
+        Err(SerializerError::UnserializableType {
+            type_name: "unit variant",
+        })
     }
 
     fn serialize_newtype_struct<T: ?Sized>(
         self,
         _name: &'static str,
-        value: &T
+        value: &T,
     ) -> Result<Self::Ok, Self::Error>
-    where T: ser::Serialize,
+    where
+        T: ser::Serialize,
     {
         value.serialize(self)
     }
@@ -97,15 +106,20 @@ impl<'a> ser::Serializer for Serializer<'a> {
         _name: &'static str,
         _variant_index: u32,
         _variant: &'static str,
-        _value: &T
+        _value: &T,
     ) -> Result<Self::Ok, Self::Error>
-    where T: ser::Serialize,
+    where
+        T: ser::Serialize,
     {
-        Err(SerializerError::UnserializableType { type_name: "newtype variant" })
+        Err(SerializerError::UnserializableType {
+            type_name: "newtype variant",
+        })
     }
 
     fn serialize_seq(self, _len: Option<usize>) -> Result<Self::SerializeSeq, Self::Error> {
-        Err(SerializerError::UnserializableType { type_name: "sequence" })
+        Err(SerializerError::UnserializableType {
+            type_name: "sequence",
+        })
     }
 
     fn serialize_tuple(self, _len: usize) -> Result<Self::SerializeTuple, Self::Error> {
@@ -115,10 +129,11 @@ impl<'a> ser::Serializer for Serializer<'a> {
     fn serialize_tuple_struct(
         self,
         _name: &'static str,
-        _len: usize
-    ) -> Result<Self::SerializeTupleStruct, Self::Error>
-    {
-        Err(SerializerError::UnserializableType { type_name: "tuple struct" })
+        _len: usize,
+    ) -> Result<Self::SerializeTupleStruct, Self::Error> {
+        Err(SerializerError::UnserializableType {
+            type_name: "tuple struct",
+        })
     }
 
     fn serialize_tuple_variant(
@@ -126,10 +141,11 @@ impl<'a> ser::Serializer for Serializer<'a> {
         _name: &'static str,
         _variant_index: u32,
         _variant: &'static str,
-        _len: usize
-    ) -> Result<Self::SerializeTupleVariant, Self::Error>
-    {
-        Err(SerializerError::UnserializableType { type_name: "tuple variant" })
+        _len: usize,
+    ) -> Result<Self::SerializeTupleVariant, Self::Error> {
+        Err(SerializerError::UnserializableType {
+            type_name: "tuple variant",
+        })
     }
 
     fn serialize_map(self, _len: Option<usize>) -> Result<Self::SerializeMap, Self::Error> {
@@ -147,9 +163,8 @@ impl<'a> ser::Serializer for Serializer<'a> {
     fn serialize_struct(
         self,
         _name: &'static str,
-        _len: usize
-    ) -> Result<Self::SerializeStruct, Self::Error>
-    {
+        _len: usize,
+    ) -> Result<Self::SerializeStruct, Self::Error> {
         Ok(StructSerializer {
             schema: self.schema,
             document_id: self.document_id,
@@ -165,10 +180,11 @@ impl<'a> ser::Serializer for Serializer<'a> {
         _name: &'static str,
         _variant_index: u32,
         _variant: &'static str,
-        _len: usize
-    ) -> Result<Self::SerializeStructVariant, Self::Error>
-    {
-        Err(SerializerError::UnserializableType { type_name: "struct variant" })
+        _len: usize,
+    ) -> Result<Self::SerializeStructVariant, Self::Error> {
+        Err(SerializerError::UnserializableType {
+            type_name: "struct variant",
+        })
     }
 }
 
@@ -187,7 +203,8 @@ impl<'a> ser::SerializeMap for MapSerializer<'a> {
     type Error = SerializerError;
 
     fn serialize_key<T: ?Sized>(&mut self, key: &T) -> Result<(), Self::Error>
-    where T: ser::Serialize,
+    where
+        T: ser::Serialize,
     {
         let key = key.serialize(ConvertToString)?;
         self.current_key_name = Some(key);
@@ -195,7 +212,8 @@ impl<'a> ser::SerializeMap for MapSerializer<'a> {
     }
 
     fn serialize_value<T: ?Sized>(&mut self, value: &T) -> Result<(), Self::Error>
-    where T: ser::Serialize,
+    where
+        T: ser::Serialize,
     {
         let key = self.current_key_name.take().unwrap();
         self.serialize_entry(&key, value)
@@ -206,7 +224,9 @@ impl<'a> ser::SerializeMap for MapSerializer<'a> {
         key: &K,
         value: &V,
     ) -> Result<(), Self::Error>
-    where K: ser::Serialize, V: ser::Serialize,
+    where
+        K: ser::Serialize,
+        V: ser::Serialize,
     {
         let key = key.serialize(ConvertToString)?;
 
@@ -245,7 +265,8 @@ impl<'a> ser::SerializeStruct for StructSerializer<'a> {
         key: &'static str,
         value: &T,
     ) -> Result<(), Self::Error>
-    where T: ser::Serialize,
+    where
+        T: ser::Serialize,
     {
         serialize_value(
             self.schema,
@@ -274,7 +295,8 @@ fn serialize_value<T: ?Sized>(
     key: &str,
     value: &T,
 ) -> Result<(), SerializerError>
-where T: ser::Serialize,
+where
+    T: ser::Serialize,
 {
     if let Some(attribute) = schema.attribute(key) {
         let props = schema.props(attribute);
@@ -283,7 +305,11 @@ where T: ser::Serialize,
         document_store.set_document_field(document_id, attribute, serialized);
 
         if props.is_indexed() {
-            let indexer = Indexer { attribute, indexer, document_id };
+            let indexer = Indexer {
+                attribute,
+                indexer,
+                document_id,
+            };
             if let Some(number_of_words) = value.serialize(indexer)? {
                 documents_fields_counts.insert((document_id, attribute), number_of_words as u64);
             }
diff --git a/meilidb-core/src/store/docs_words.rs b/meilidb-core/src/store/docs_words.rs
index 6cdf555d1..d52c4b2c6 100644
--- a/meilidb-core/src/store/docs_words.rs
+++ b/meilidb-core/src/store/docs_words.rs
@@ -1,8 +1,8 @@
-use std::sync::Arc;
-use zlmdb::types::{OwnedType, ByteSlice};
-use zlmdb::Result as ZResult;
-use crate::DocumentId;
 use super::BEU64;
+use crate::DocumentId;
+use std::sync::Arc;
+use zlmdb::types::{ByteSlice, OwnedType};
+use zlmdb::Result as ZResult;
 
 #[derive(Copy, Clone)]
 pub struct DocsWords {
@@ -15,8 +15,7 @@ impl DocsWords {
         writer: &mut zlmdb::RwTxn,
         document_id: DocumentId,
         words: &fst::Set,
-    ) -> ZResult<()>
-    {
+    ) -> ZResult<()> {
         let document_id = BEU64::new(document_id.0);
         let bytes = words.as_fst().as_bytes();
         self.docs_words.put(writer, &document_id, bytes)
@@ -26,8 +25,7 @@ impl DocsWords {
         &self,
         writer: &mut zlmdb::RwTxn,
         document_id: DocumentId,
-    ) -> ZResult<bool>
-    {
+    ) -> ZResult<bool> {
         let document_id = BEU64::new(document_id.0);
         self.docs_words.delete(writer, &document_id)
     }
@@ -36,8 +34,7 @@ impl DocsWords {
         &self,
         reader: &zlmdb::RoTxn,
         document_id: DocumentId,
-    ) -> ZResult<Option<fst::Set>>
-    {
+    ) -> ZResult<Option<fst::Set>> {
         let document_id = BEU64::new(document_id.0);
         match self.docs_words.get(reader, &document_id)? {
             Some(bytes) => {
@@ -45,7 +42,7 @@ impl DocsWords {
                 let bytes = Arc::from(bytes);
                 let fst = fst::raw::Fst::from_shared_bytes(bytes, 0, len).unwrap();
                 Ok(Some(fst::Set::from(fst)))
-            },
+            }
             None => Ok(None),
         }
     }
diff --git a/meilidb-core/src/store/documents_fields.rs b/meilidb-core/src/store/documents_fields.rs
index 7b528af97..ee5bde1b3 100644
--- a/meilidb-core/src/store/documents_fields.rs
+++ b/meilidb-core/src/store/documents_fields.rs
@@ -1,9 +1,9 @@
 use meilidb_schema::SchemaAttr;
-use zlmdb::types::{OwnedType, ByteSlice};
+use zlmdb::types::{ByteSlice, OwnedType};
 use zlmdb::Result as ZResult;
 
-use crate::DocumentId;
 use super::DocumentAttrKey;
+use crate::DocumentId;
 
 #[derive(Copy, Clone)]
 pub struct DocumentsFields {
@@ -17,8 +17,7 @@ impl DocumentsFields {
         document_id: DocumentId,
         attribute: SchemaAttr,
         value: &[u8],
-    ) -> ZResult<()>
-    {
+    ) -> ZResult<()> {
         let key = DocumentAttrKey::new(document_id, attribute);
         self.documents_fields.put(writer, &key, value)
     }
@@ -27,8 +26,7 @@ impl DocumentsFields {
         &self,
         writer: &mut zlmdb::RwTxn,
         document_id: DocumentId,
-    ) -> ZResult<usize>
-    {
+    ) -> ZResult<usize> {
         let start = DocumentAttrKey::new(document_id, SchemaAttr::min());
         let end = DocumentAttrKey::new(document_id, SchemaAttr::max());
         self.documents_fields.delete_range(writer, start..=end)
@@ -39,8 +37,7 @@ impl DocumentsFields {
         reader: &'txn zlmdb::RoTxn,
         document_id: DocumentId,
         attribute: SchemaAttr,
-    ) -> ZResult<Option<&'txn [u8]>>
-    {
+    ) -> ZResult<Option<&'txn [u8]>> {
         let key = DocumentAttrKey::new(document_id, attribute);
         self.documents_fields.get(reader, &key)
     }
@@ -49,8 +46,7 @@ impl DocumentsFields {
         &self,
         reader: &'txn zlmdb::RoTxn,
         document_id: DocumentId,
-    ) -> ZResult<DocumentFieldsIter<'txn>>
-    {
+    ) -> ZResult<DocumentFieldsIter<'txn>> {
         let start = DocumentAttrKey::new(document_id, SchemaAttr::min());
         let end = DocumentAttrKey::new(document_id, SchemaAttr::max());
         let iter = self.documents_fields.range(reader, start..=end)?;
@@ -70,7 +66,7 @@ impl<'txn> Iterator for DocumentFieldsIter<'txn> {
             Some(Ok((key, bytes))) => {
                 let attr = SchemaAttr(key.attr.get());
                 Some(Ok((attr, bytes)))
-            },
+            }
             Some(Err(e)) => Some(Err(e.into())),
             None => None,
         }
diff --git a/meilidb-core/src/store/documents_fields_counts.rs b/meilidb-core/src/store/documents_fields_counts.rs
index c075f703b..379687e5b 100644
--- a/meilidb-core/src/store/documents_fields_counts.rs
+++ b/meilidb-core/src/store/documents_fields_counts.rs
@@ -1,8 +1,8 @@
+use super::DocumentAttrKey;
+use crate::DocumentId;
 use meilidb_schema::SchemaAttr;
 use zlmdb::types::OwnedType;
 use zlmdb::Result as ZResult;
-use crate::DocumentId;
-use super::DocumentAttrKey;
 
 #[derive(Copy, Clone)]
 pub struct DocumentsFieldsCounts {
@@ -16,8 +16,7 @@ impl DocumentsFieldsCounts {
         document_id: DocumentId,
         attribute: SchemaAttr,
         value: u64,
-    ) -> ZResult<()>
-    {
+    ) -> ZResult<()> {
         let key = DocumentAttrKey::new(document_id, attribute);
         self.documents_fields_counts.put(writer, &key, &value)
     }
@@ -26,11 +25,11 @@ impl DocumentsFieldsCounts {
         &self,
         writer: &mut zlmdb::RwTxn,
         document_id: DocumentId,
-    ) -> ZResult<usize>
-    {
+    ) -> ZResult<usize> {
         let start = DocumentAttrKey::new(document_id, SchemaAttr::min());
         let end = DocumentAttrKey::new(document_id, SchemaAttr::max());
-        self.documents_fields_counts.delete_range(writer, start..=end)
+        self.documents_fields_counts
+            .delete_range(writer, start..=end)
     }
 
     pub fn document_field_count(
@@ -38,8 +37,7 @@ impl DocumentsFieldsCounts {
         reader: &zlmdb::RoTxn,
         document_id: DocumentId,
         attribute: SchemaAttr,
-    ) -> ZResult<Option<u64>>
-    {
+    ) -> ZResult<Option<u64>> {
         let key = DocumentAttrKey::new(document_id, attribute);
         match self.documents_fields_counts.get(reader, &key)? {
             Some(count) => Ok(Some(count)),
@@ -51,8 +49,7 @@ impl DocumentsFieldsCounts {
         &self,
         reader: &'txn zlmdb::RoTxn,
         document_id: DocumentId,
-    ) -> ZResult<DocumentFieldsCountsIter<'txn>>
-    {
+    ) -> ZResult<DocumentFieldsCountsIter<'txn>> {
         let start = DocumentAttrKey::new(document_id, SchemaAttr::min());
         let end = DocumentAttrKey::new(document_id, SchemaAttr::max());
         let iter = self.documents_fields_counts.range(reader, start..=end)?;
@@ -62,17 +59,18 @@ impl DocumentsFieldsCounts {
     pub fn documents_ids<'txn>(
         &self,
         reader: &'txn zlmdb::RoTxn,
-    ) -> ZResult<DocumentsIdsIter<'txn>>
-    {
+    ) -> ZResult<DocumentsIdsIter<'txn>> {
         let iter = self.documents_fields_counts.iter(reader)?;
-        Ok(DocumentsIdsIter { last_seen_id: None, iter })
+        Ok(DocumentsIdsIter {
+            last_seen_id: None,
+            iter,
+        })
     }
 
     pub fn all_documents_fields_counts<'txn>(
         &self,
         reader: &'txn zlmdb::RoTxn,
-    ) -> ZResult<AllDocumentsFieldsCountsIter<'txn>>
-    {
+    ) -> ZResult<AllDocumentsFieldsCountsIter<'txn>> {
         let iter = self.documents_fields_counts.iter(reader)?;
         Ok(AllDocumentsFieldsCountsIter { iter })
     }
@@ -90,7 +88,7 @@ impl Iterator for DocumentFieldsCountsIter<'_> {
             Some(Ok((key, count))) => {
                 let attr = SchemaAttr(key.attr.get());
                 Some(Ok((attr, count)))
-            },
+            }
             Some(Err(e)) => Some(Err(e.into())),
             None => None,
         }
@@ -112,9 +110,9 @@ impl Iterator for DocumentsIdsIter<'_> {
                     let document_id = DocumentId(key.docid.get());
                     if Some(document_id) != self.last_seen_id {
                         self.last_seen_id = Some(document_id);
-                        return Some(Ok(document_id))
+                        return Some(Ok(document_id));
                     }
-                },
+                }
                 Err(e) => return Some(Err(e.into())),
             }
         }
@@ -135,7 +133,7 @@ impl<'r> Iterator for AllDocumentsFieldsCountsIter<'r> {
                 let docid = DocumentId(key.docid.get());
                 let attr = SchemaAttr(key.attr.get());
                 Some(Ok((docid, attr, count)))
-            },
+            }
             Some(Err(e)) => Some(Err(e.into())),
             None => None,
         }
diff --git a/meilidb-core/src/store/main.rs b/meilidb-core/src/store/main.rs
index 085609e4f..86e638582 100644
--- a/meilidb-core/src/store/main.rs
+++ b/meilidb-core/src/store/main.rs
@@ -1,15 +1,15 @@
-use std::sync::Arc;
-use meilidb_schema::Schema;
-use zlmdb::types::{Str, OwnedType, ByteSlice, Serde};
-use zlmdb::Result as ZResult;
 use crate::RankedMap;
+use meilidb_schema::Schema;
+use std::sync::Arc;
+use zlmdb::types::{ByteSlice, OwnedType, Serde, Str};
+use zlmdb::Result as ZResult;
 
-const CUSTOMS_KEY:             &str = "customs-key";
+const CUSTOMS_KEY: &str = "customs-key";
 const NUMBER_OF_DOCUMENTS_KEY: &str = "number-of-documents";
-const RANKED_MAP_KEY:          &str = "ranked-map";
-const SCHEMA_KEY:              &str = "schema";
-const SYNONYMS_KEY:            &str = "synonyms";
-const WORDS_KEY:               &str = "words";
+const RANKED_MAP_KEY: &str = "ranked-map";
+const SCHEMA_KEY: &str = "schema";
+const SYNONYMS_KEY: &str = "synonyms";
+const WORDS_KEY: &str = "words";
 
 #[derive(Copy, Clone)]
 pub struct Main {
@@ -29,13 +29,14 @@ impl Main {
                 let bytes = Arc::from(bytes);
                 let fst = fst::raw::Fst::from_shared_bytes(bytes, 0, len).unwrap();
                 Ok(Some(fst::Set::from(fst)))
-            },
+            }
             None => Ok(None),
         }
     }
 
     pub fn put_schema(&self, writer: &mut zlmdb::RwTxn, schema: &Schema) -> ZResult<()> {
-        self.main.put::<Str, Serde<Schema>>(writer, SCHEMA_KEY, schema)
+        self.main
+            .put::<Str, Serde<Schema>>(writer, SCHEMA_KEY, schema)
     }
 
     pub fn schema(&self, reader: &zlmdb::RoTxn) -> ZResult<Option<Schema>> {
@@ -43,11 +44,13 @@ impl Main {
     }
 
     pub fn put_ranked_map(&self, writer: &mut zlmdb::RwTxn, ranked_map: &RankedMap) -> ZResult<()> {
-        self.main.put::<Str, Serde<RankedMap>>(writer, RANKED_MAP_KEY, &ranked_map)
+        self.main
+            .put::<Str, Serde<RankedMap>>(writer, RANKED_MAP_KEY, &ranked_map)
     }
 
     pub fn ranked_map(&self, reader: &zlmdb::RoTxn) -> ZResult<Option<RankedMap>> {
-        self.main.get::<Str, Serde<RankedMap>>(reader, RANKED_MAP_KEY)
+        self.main
+            .get::<Str, Serde<RankedMap>>(reader, RANKED_MAP_KEY)
     }
 
     pub fn put_synonyms_fst(&self, writer: &mut zlmdb::RwTxn, fst: &fst::Set) -> ZResult<()> {
@@ -62,28 +65,34 @@ impl Main {
                 let bytes = Arc::from(bytes);
                 let fst = fst::raw::Fst::from_shared_bytes(bytes, 0, len).unwrap();
                 Ok(Some(fst::Set::from(fst)))
-            },
+            }
             None => Ok(None),
         }
     }
 
     pub fn put_number_of_documents<F>(&self, writer: &mut zlmdb::RwTxn, f: F) -> ZResult<u64>
-    where F: Fn(u64) -> u64,
+    where
+        F: Fn(u64) -> u64,
     {
         let new = self.number_of_documents(writer).map(f)?;
-        self.main.put::<Str, OwnedType<u64>>(writer, NUMBER_OF_DOCUMENTS_KEY, &new)?;
+        self.main
+            .put::<Str, OwnedType<u64>>(writer, NUMBER_OF_DOCUMENTS_KEY, &new)?;
         Ok(new)
     }
 
     pub fn number_of_documents(&self, reader: &zlmdb::RoTxn) -> ZResult<u64> {
-        match self.main.get::<Str, OwnedType<u64>>(reader, NUMBER_OF_DOCUMENTS_KEY)? {
+        match self
+            .main
+            .get::<Str, OwnedType<u64>>(reader, NUMBER_OF_DOCUMENTS_KEY)?
+        {
             Some(value) => Ok(value),
             None => Ok(0),
         }
     }
 
     pub fn put_customs(&self, writer: &mut zlmdb::RwTxn, customs: &[u8]) -> ZResult<()> {
-        self.main.put::<Str, ByteSlice>(writer, CUSTOMS_KEY, customs)
+        self.main
+            .put::<Str, ByteSlice>(writer, CUSTOMS_KEY, customs)
     }
 
     pub fn customs<'txn>(&self, reader: &'txn zlmdb::RoTxn) -> ZResult<Option<&'txn [u8]>> {
diff --git a/meilidb-core/src/store/mod.rs b/meilidb-core/src/store/mod.rs
index fee4e8d8a..11c1447eb 100644
--- a/meilidb-core/src/store/mod.rs
+++ b/meilidb-core/src/store/mod.rs
@@ -8,8 +8,10 @@ mod updates;
 mod updates_results;
 
 pub use self::docs_words::DocsWords;
-pub use self::documents_fields::{DocumentsFields, DocumentFieldsIter};
-pub use self::documents_fields_counts::{DocumentsFieldsCounts, DocumentFieldsCountsIter, DocumentsIdsIter};
+pub use self::documents_fields::{DocumentFieldsIter, DocumentsFields};
+pub use self::documents_fields_counts::{
+    DocumentFieldsCountsIter, DocumentsFieldsCounts, DocumentsIdsIter,
+};
 pub use self::main::Main;
 pub use self::postings_lists::PostingsLists;
 pub use self::synonyms::Synonyms;
@@ -25,19 +27,24 @@ use zlmdb::Result as ZResult;
 
 use crate::criterion::Criteria;
 use crate::serde::Deserializer;
-use crate::{update, query_builder::QueryBuilder, DocumentId, MResult, Error};
+use crate::{query_builder::QueryBuilder, update, DocumentId, Error, MResult};
 
 type BEU64 = zerocopy::U64<byteorder::BigEndian>;
 type BEU16 = zerocopy::U16<byteorder::BigEndian>;
 
-#[derive(Debug, Copy, Clone)]
-#[derive(AsBytes, FromBytes)]
+#[derive(Debug, Copy, Clone, AsBytes, FromBytes)]
 #[repr(C)]
-pub struct DocumentAttrKey { docid: BEU64, attr: BEU16 }
+pub struct DocumentAttrKey {
+    docid: BEU64,
+    attr: BEU16,
+}
 
 impl DocumentAttrKey {
     fn new(docid: DocumentId, attr: SchemaAttr) -> DocumentAttrKey {
-        DocumentAttrKey { docid: BEU64::new(docid.0), attr: BEU16::new(attr.0) }
+        DocumentAttrKey {
+            docid: BEU64::new(docid.0),
+            attr: BEU16::new(attr.0),
+        }
     }
 }
 
@@ -93,13 +100,15 @@ impl Index {
         reader: &zlmdb::RoTxn,
         attributes: Option<&HashSet<&str>>,
         document_id: DocumentId,
-    ) -> MResult<Option<T>>
-    {
+    ) -> MResult<Option<T>> {
         let schema = self.main.schema(reader)?;
         let schema = schema.ok_or(Error::SchemaMissing)?;
 
         let attributes = match attributes {
-            Some(attributes) => attributes.into_iter().map(|name| schema.attribute(name)).collect(),
+            Some(attributes) => attributes
+                .into_iter()
+                .map(|name| schema.attribute(name))
+                .collect(),
             None => None,
         };
 
@@ -121,9 +130,10 @@ impl Index {
         reader: &zlmdb::RoTxn,
         document_id: DocumentId,
         attribute: SchemaAttr,
-    ) -> MResult<Option<T>>
-    {
-        let bytes = self.documents_fields.document_attribute(reader, document_id, attribute)?;
+    ) -> MResult<Option<T>> {
+        let bytes = self
+            .documents_fields
+            .document_attribute(reader, document_id, attribute)?;
         match bytes {
             Some(bytes) => Ok(Some(serde_json::from_slice(bytes)?)),
             None => Ok(None),
@@ -183,14 +193,8 @@ impl Index {
         &self,
         reader: &zlmdb::RoTxn,
         update_id: u64,
-    ) -> MResult<update::UpdateStatus>
-    {
-        update::update_status(
-            reader,
-            self.updates,
-            self.updates_results,
-            update_id,
-        )
+    ) -> MResult<update::UpdateStatus> {
+        update::update_status(reader, self.updates, self.updates_results, update_id)
     }
 
     pub fn query_builder(&self) -> QueryBuilder {
@@ -205,8 +209,7 @@ impl Index {
     pub fn query_builder_with_criteria<'c, 'f, 'd>(
         &self,
         criteria: Criteria<'c>,
-    ) -> QueryBuilder<'c, 'f, 'd>
-    {
+    ) -> QueryBuilder<'c, 'f, 'd> {
         QueryBuilder::with_criteria(
             self.main,
             self.postings_lists,
@@ -221,8 +224,7 @@ pub fn create(
     env: &zlmdb::Env,
     name: &str,
     updates_notifier: crossbeam_channel::Sender<()>,
-) -> MResult<Index>
-{
+) -> MResult<Index> {
     // create all the store names
     let main_name = main_name(name);
     let postings_lists_name = postings_lists_name(name);
@@ -247,7 +249,9 @@ pub fn create(
         main: Main { main },
         postings_lists: PostingsLists { postings_lists },
         documents_fields: DocumentsFields { documents_fields },
-        documents_fields_counts: DocumentsFieldsCounts { documents_fields_counts },
+        documents_fields_counts: DocumentsFieldsCounts {
+            documents_fields_counts,
+        },
         synonyms: Synonyms { synonyms },
         docs_words: DocsWords { docs_words },
         updates: Updates { updates },
@@ -260,8 +264,7 @@ pub fn open(
     env: &zlmdb::Env,
     name: &str,
     updates_notifier: crossbeam_channel::Sender<()>,
-) -> MResult<Option<Index>>
-{
+) -> MResult<Option<Index>> {
     // create all the store names
     let main_name = main_name(name);
     let postings_lists_name = postings_lists_name(name);
@@ -310,7 +313,9 @@ pub fn open(
         main: Main { main },
         postings_lists: PostingsLists { postings_lists },
         documents_fields: DocumentsFields { documents_fields },
-        documents_fields_counts: DocumentsFieldsCounts { documents_fields_counts },
+        documents_fields_counts: DocumentsFieldsCounts {
+            documents_fields_counts,
+        },
         synonyms: Synonyms { synonyms },
         docs_words: DocsWords { docs_words },
         updates: Updates { updates },
diff --git a/meilidb-core/src/store/postings_lists.rs b/meilidb-core/src/store/postings_lists.rs
index eb917df5b..041c2319b 100644
--- a/meilidb-core/src/store/postings_lists.rs
+++ b/meilidb-core/src/store/postings_lists.rs
@@ -1,8 +1,8 @@
-use std::borrow::Cow;
+use crate::DocIndex;
 use sdset::{Set, SetBuf};
+use std::borrow::Cow;
 use zlmdb::types::{ByteSlice, CowSlice};
 use zlmdb::Result as ZResult;
-use crate::DocIndex;
 
 #[derive(Copy, Clone)]
 pub struct PostingsLists {
@@ -15,8 +15,7 @@ impl PostingsLists {
         writer: &mut zlmdb::RwTxn,
         word: &[u8],
         words_indexes: &Set<DocIndex>,
-    ) -> ZResult<()>
-    {
+    ) -> ZResult<()> {
         self.postings_lists.put(writer, word, words_indexes)
     }
 
@@ -28,8 +27,7 @@ impl PostingsLists {
         &self,
         reader: &'txn zlmdb::RoTxn,
         word: &[u8],
-    ) -> ZResult<Option<Cow<'txn, Set<DocIndex>>>>
-    {
+    ) -> ZResult<Option<Cow<'txn, Set<DocIndex>>>> {
         match self.postings_lists.get(reader, word)? {
             Some(Cow::Borrowed(slice)) => Ok(Some(Cow::Borrowed(Set::new_unchecked(slice)))),
             Some(Cow::Owned(vec)) => Ok(Some(Cow::Owned(SetBuf::new_unchecked(vec)))),
diff --git a/meilidb-core/src/store/synonyms.rs b/meilidb-core/src/store/synonyms.rs
index ca032c223..1ddaae9e2 100644
--- a/meilidb-core/src/store/synonyms.rs
+++ b/meilidb-core/src/store/synonyms.rs
@@ -13,8 +13,7 @@ impl Synonyms {
         writer: &mut zlmdb::RwTxn,
         word: &[u8],
         synonyms: &fst::Set,
-    ) -> ZResult<()>
-    {
+    ) -> ZResult<()> {
         let bytes = synonyms.as_fst().as_bytes();
         self.synonyms.put(writer, word, bytes)
     }
@@ -30,7 +29,7 @@ impl Synonyms {
                 let bytes = Arc::from(bytes);
                 let fst = fst::raw::Fst::from_shared_bytes(bytes, 0, len).unwrap();
                 Ok(Some(fst::Set::from(fst)))
-            },
+            }
             None => Ok(None),
         }
     }
diff --git a/meilidb-core/src/store/updates.rs b/meilidb-core/src/store/updates.rs
index 7ec3b48aa..7bc195895 100644
--- a/meilidb-core/src/store/updates.rs
+++ b/meilidb-core/src/store/updates.rs
@@ -1,13 +1,16 @@
+use super::BEU64;
+use crate::update::Update;
+use serde::{Deserialize, Serialize};
 use std::borrow::Cow;
 use zlmdb::types::OwnedType;
-use zlmdb::{Result as ZResult, BytesEncode, BytesDecode};
-use serde::{Serialize, Deserialize};
-use crate::update::Update;
-use super::BEU64;
+use zlmdb::{BytesDecode, BytesEncode, Result as ZResult};
 
 pub struct SerdeJson<T>(std::marker::PhantomData<T>);
 
-impl<T> BytesEncode for SerdeJson<T> where T: Serialize {
+impl<T> BytesEncode for SerdeJson<T>
+where
+    T: Serialize,
+{
     type EItem = T;
 
     fn bytes_encode(item: &Self::EItem) -> Option<Cow<[u8]>> {
@@ -15,7 +18,10 @@ impl<T> BytesEncode for SerdeJson<T> where T: Serialize {
     }
 }
 
-impl<'a, T: 'a> BytesDecode<'a> for SerdeJson<T> where T: Deserialize<'a> + Clone {
+impl<'a, T: 'a> BytesDecode<'a> for SerdeJson<T>
+where
+    T: Deserialize<'a> + Clone,
+{
     type DItem = T;
 
     fn bytes_decode(bytes: &'a [u8]) -> Option<Self::DItem> {
@@ -56,8 +62,7 @@ impl Updates {
         writer: &mut zlmdb::RwTxn,
         update_id: u64,
         update: &Update,
-    ) -> ZResult<()>
-    {
+    ) -> ZResult<()> {
         // TODO prefer using serde_json?
         let update_id = BEU64::new(update_id);
         self.updates.put(writer, &update_id, update)
@@ -69,8 +74,8 @@ impl Updates {
                 let key = BEU64::new(update_id);
                 self.updates.delete(writer, &key)?;
                 Ok(Some((update_id, update)))
-            },
-            None => Ok(None)
+            }
+            None => Ok(None),
         }
     }
 }
diff --git a/meilidb-core/src/store/updates_results.rs b/meilidb-core/src/store/updates_results.rs
index 8deeb2f5b..f9d28112d 100644
--- a/meilidb-core/src/store/updates_results.rs
+++ b/meilidb-core/src/store/updates_results.rs
@@ -1,7 +1,7 @@
+use super::BEU64;
+use crate::update::UpdateResult;
 use zlmdb::types::{OwnedType, Serde};
 use zlmdb::Result as ZResult;
-use crate::update::UpdateResult;
-use super::BEU64;
 
 #[derive(Copy, Clone)]
 pub struct UpdatesResults {
@@ -21,8 +21,7 @@ impl UpdatesResults {
         writer: &mut zlmdb::RwTxn,
         update_id: u64,
         update_result: &UpdateResult,
-    ) -> ZResult<()>
-    {
+    ) -> ZResult<()> {
         let update_id = BEU64::new(update_id);
         self.updates_results.put(writer, &update_id, update_result)
     }
@@ -31,8 +30,7 @@ impl UpdatesResults {
         &self,
         reader: &zlmdb::RoTxn,
         update_id: u64,
-    ) -> ZResult<Option<UpdateResult>>
-    {
+    ) -> ZResult<Option<UpdateResult>> {
         let update_id = BEU64::new(update_id);
         self.updates_results.get(reader, &update_id)
     }
diff --git a/meilidb-core/src/update/customs_update.rs b/meilidb-core/src/update/customs_update.rs
index 2303b8689..5072dc096 100644
--- a/meilidb-core/src/update/customs_update.rs
+++ b/meilidb-core/src/update/customs_update.rs
@@ -1,13 +1,12 @@
-use zlmdb::Result as ZResult;
-use crate::update::{Update, next_update_id};
 use crate::store;
+use crate::update::{next_update_id, Update};
+use zlmdb::Result as ZResult;
 
 pub fn apply_customs_update(
     writer: &mut zlmdb::RwTxn,
     main_store: store::Main,
     customs: &[u8],
-) -> ZResult<()>
-{
+) -> ZResult<()> {
     main_store.put_customs(writer, customs)
 }
 
@@ -16,8 +15,7 @@ pub fn push_customs_update(
     updates_store: store::Updates,
     updates_results_store: store::UpdatesResults,
     customs: Vec<u8>,
-) -> ZResult<u64>
-{
+) -> ZResult<u64> {
     let last_update_id = next_update_id(writer, updates_store, updates_results_store)?;
 
     let update = Update::Customs(customs);
diff --git a/meilidb-core/src/update/documents_addition.rs b/meilidb-core/src/update/documents_addition.rs
index e57812f0d..22769fbe2 100644
--- a/meilidb-core/src/update/documents_addition.rs
+++ b/meilidb-core/src/update/documents_addition.rs
@@ -1,14 +1,14 @@
 use std::collections::{HashMap, HashSet};
 
-use fst::{SetBuilder, set::OpBuilder};
-use sdset::{SetOperation, duo::Union};
+use fst::{set::OpBuilder, SetBuilder};
+use sdset::{duo::Union, SetOperation};
 use serde::Serialize;
 
 use crate::raw_indexer::RawIndexer;
-use crate::serde::{extract_document_id, Serializer, RamDocumentStore};
+use crate::serde::{extract_document_id, RamDocumentStore, Serializer};
 use crate::store;
-use crate::update::{Update, next_update_id, apply_documents_deletion};
-use crate::{MResult, Error, RankedMap};
+use crate::update::{apply_documents_deletion, next_update_id, Update};
+use crate::{Error, MResult, RankedMap};
 
 pub struct DocumentsAddition<D> {
     updates_store: store::Updates,
@@ -22,8 +22,7 @@ impl<D> DocumentsAddition<D> {
         updates_store: store::Updates,
         updates_results_store: store::UpdatesResults,
         updates_notifier: crossbeam_channel::Sender<()>,
-    ) -> DocumentsAddition<D>
-    {
+    ) -> DocumentsAddition<D> {
         DocumentsAddition {
             updates_store,
             updates_results_store,
@@ -37,7 +36,8 @@ impl<D> DocumentsAddition<D> {
     }
 
     pub fn finalize(self, writer: &mut zlmdb::RwTxn) -> MResult<u64>
-    where D: serde::Serialize
+    where
+        D: serde::Serialize,
     {
         let _ = self.updates_notifier.send(());
         let update_id = push_documents_addition(
@@ -51,7 +51,7 @@ impl<D> DocumentsAddition<D> {
 }
 
 impl<D> Extend<D> for DocumentsAddition<D> {
-    fn extend<T: IntoIterator<Item=D>>(&mut self, iter: T) {
+    fn extend<T: IntoIterator<Item = D>>(&mut self, iter: T) {
         self.documents.extend(iter)
     }
 }
@@ -61,8 +61,7 @@ pub fn push_documents_addition<D: serde::Serialize>(
     updates_store: store::Updates,
     updates_results_store: store::UpdatesResults,
     addition: Vec<D>,
-) -> MResult<u64>
-{
+) -> MResult<u64> {
     let mut values = Vec::with_capacity(addition.len());
     for add in addition {
         let vec = serde_json::to_vec(&add)?;
@@ -87,8 +86,7 @@ pub fn apply_documents_addition(
     docs_words_store: store::DocsWords,
     mut ranked_map: RankedMap,
     addition: Vec<serde_json::Value>,
-) -> MResult<()>
-{
+) -> MResult<()> {
     let mut document_ids = HashSet::new();
     let mut document_store = RamDocumentStore::new();
     let mut document_fields_counts = HashMap::new();
@@ -182,7 +180,7 @@ pub fn apply_documents_addition(
                 .into_inner()
                 .and_then(fst::Set::from_bytes)
                 .unwrap()
-        },
+        }
         None => delta_words,
     };
 
diff --git a/meilidb-core/src/update/documents_deletion.rs b/meilidb-core/src/update/documents_deletion.rs
index 72c03f741..e640cb508 100644
--- a/meilidb-core/src/update/documents_deletion.rs
+++ b/meilidb-core/src/update/documents_deletion.rs
@@ -1,13 +1,13 @@
-use std::collections::{HashMap, HashSet, BTreeSet};
+use std::collections::{BTreeSet, HashMap, HashSet};
 
 use fst::{SetBuilder, Streamer};
 use meilidb_schema::Schema;
-use sdset::{SetBuf, SetOperation, duo::DifferenceByKey};
+use sdset::{duo::DifferenceByKey, SetBuf, SetOperation};
 
-use crate::{DocumentId, RankedMap, MResult, Error};
 use crate::serde::extract_document_id;
-use crate::update::{Update, next_update_id};
 use crate::store;
+use crate::update::{next_update_id, Update};
+use crate::{DocumentId, Error, MResult, RankedMap};
 
 pub struct DocumentsDeletion {
     updates_store: store::Updates,
@@ -21,8 +21,7 @@ impl DocumentsDeletion {
         updates_store: store::Updates,
         updates_results_store: store::UpdatesResults,
         updates_notifier: crossbeam_channel::Sender<()>,
-    ) -> DocumentsDeletion
-    {
+    ) -> DocumentsDeletion {
         DocumentsDeletion {
             updates_store,
             updates_results_store,
@@ -36,7 +35,8 @@ impl DocumentsDeletion {
     }
 
     pub fn delete_document<D>(&mut self, schema: &Schema, document: D) -> MResult<()>
-    where D: serde::Serialize,
+    where
+        D: serde::Serialize,
     {
         let identifier = schema.identifier_name();
         let document_id = match extract_document_id(identifier, &document)? {
@@ -62,7 +62,7 @@ impl DocumentsDeletion {
 }
 
 impl Extend<DocumentId> for DocumentsDeletion {
-    fn extend<T: IntoIterator<Item=DocumentId>>(&mut self, iter: T) {
+    fn extend<T: IntoIterator<Item = DocumentId>>(&mut self, iter: T) {
         self.documents.extend(iter)
     }
 }
@@ -72,8 +72,7 @@ pub fn push_documents_deletion(
     updates_store: store::Updates,
     updates_results_store: store::UpdatesResults,
     deletion: Vec<DocumentId>,
-) -> MResult<u64>
-{
+) -> MResult<u64> {
     let last_update_id = next_update_id(writer, updates_store, updates_results_store)?;
 
     let update = Update::DocumentsDeletion(deletion);
@@ -91,8 +90,7 @@ pub fn apply_documents_deletion(
     docs_words_store: store::DocsWords,
     mut ranked_map: RankedMap,
     deletion: Vec<DocumentId>,
-) -> MResult<()>
-{
+) -> MResult<()> {
     let idset = SetBuf::from_dirty(deletion);
 
     let schema = match main_store.schema(writer)? {
@@ -101,10 +99,17 @@ pub fn apply_documents_deletion(
     };
 
     // collect the ranked attributes according to the schema
-    let ranked_attrs: Vec<_> = schema.iter()
-        .filter_map(|(_, attr, prop)| {
-            if prop.is_ranked() { Some(attr) } else { None }
-        })
+    let ranked_attrs: Vec<_> = schema
+        .iter()
+        .filter_map(
+            |(_, attr, prop)| {
+                if prop.is_ranked() {
+                    Some(attr)
+                } else {
+                    None
+                }
+            },
+        )
         .collect();
 
     let mut words_document_ids = HashMap::new();
@@ -118,7 +123,10 @@ pub fn apply_documents_deletion(
             let mut stream = words.stream();
             while let Some(word) = stream.next() {
                 let word = word.to_vec();
-                words_document_ids.entry(word).or_insert_with(Vec::new).push(id);
+                words_document_ids
+                    .entry(word)
+                    .or_insert_with(Vec::new)
+                    .push(id);
             }
         }
     }
@@ -167,7 +175,7 @@ pub fn apply_documents_deletion(
                 .into_inner()
                 .and_then(fst::Set::from_bytes)
                 .unwrap()
-        },
+        }
         None => fst::Set::default(),
     };
 
diff --git a/meilidb-core/src/update/mod.rs b/meilidb-core/src/update/mod.rs
index bf3ef831f..ea93413f1 100644
--- a/meilidb-core/src/update/mod.rs
+++ b/meilidb-core/src/update/mod.rs
@@ -6,21 +6,21 @@ mod synonyms_addition;
 mod synonyms_deletion;
 
 pub use self::customs_update::{apply_customs_update, push_customs_update};
-pub use self::documents_addition::{DocumentsAddition, apply_documents_addition};
-pub use self::documents_deletion::{DocumentsDeletion, apply_documents_deletion};
+pub use self::documents_addition::{apply_documents_addition, DocumentsAddition};
+pub use self::documents_deletion::{apply_documents_deletion, DocumentsDeletion};
 pub use self::schema_update::{apply_schema_update, push_schema_update};
-pub use self::synonyms_addition::{SynonymsAddition, apply_synonyms_addition};
-pub use self::synonyms_deletion::{SynonymsDeletion, apply_synonyms_deletion};
+pub use self::synonyms_addition::{apply_synonyms_addition, SynonymsAddition};
+pub use self::synonyms_deletion::{apply_synonyms_deletion, SynonymsDeletion};
 
-use std::time::{Duration, Instant};
-use std::collections::BTreeMap;
 use std::cmp;
+use std::collections::BTreeMap;
+use std::time::{Duration, Instant};
 
 use log::debug;
-use serde::{Serialize, Deserialize};
+use serde::{Deserialize, Serialize};
 use zlmdb::Result as ZResult;
 
-use crate::{store, MResult, DocumentId, RankedMap};
+use crate::{store, DocumentId, MResult, RankedMap};
 use meilidb_schema::Schema;
 
 #[derive(Debug, Clone, Serialize, Deserialize)]
@@ -68,8 +68,7 @@ pub fn update_status(
     updates_store: store::Updates,
     updates_results_store: store::UpdatesResults,
     update_id: u64,
-) -> MResult<UpdateStatus>
-{
+) -> MResult<UpdateStatus> {
     match updates_results_store.update_result(reader, update_id)? {
         Some(result) => Ok(UpdateStatus::Processed(result)),
         None => {
@@ -86,8 +85,7 @@ pub fn next_update_id(
     writer: &mut zlmdb::RwTxn,
     updates_store: store::Updates,
     updates_results_store: store::UpdatesResults,
-) -> ZResult<u64>
-{
+) -> ZResult<u64> {
     let last_update_id = updates_store.last_update_id(writer)?;
     let last_update_id = last_update_id.map(|(n, _)| n);
 
@@ -100,7 +98,10 @@ pub fn next_update_id(
     Ok(new_update_id)
 }
 
-pub fn update_task(writer: &mut zlmdb::RwTxn, index: store::Index) -> MResult<Option<UpdateResult>> {
+pub fn update_task(
+    writer: &mut zlmdb::RwTxn,
+    index: store::Index,
+) -> MResult<Option<UpdateResult>> {
     let (update_id, update) = match index.updates.pop_front(writer)? {
         Some(value) => value,
         None => return Ok(None),
@@ -112,11 +113,13 @@ pub fn update_task(writer: &mut zlmdb::RwTxn, index: store::Index) -> MResult<Op
         Update::Schema(schema) => {
             let start = Instant::now();
 
-            let update_type = UpdateType::Schema { schema: schema.clone() };
+            let update_type = UpdateType::Schema {
+                schema: schema.clone(),
+            };
             let result = apply_schema_update(writer, index.main, &schema);
 
             (update_type, result, start.elapsed())
-        },
+        }
         Update::Customs(customs) => {
             let start = Instant::now();
 
@@ -133,7 +136,9 @@ pub fn update_task(writer: &mut zlmdb::RwTxn, index: store::Index) -> MResult<Op
                 None => RankedMap::default(),
             };
 
-            let update_type = UpdateType::DocumentsAddition { number: documents.len() };
+            let update_type = UpdateType::DocumentsAddition {
+                number: documents.len(),
+            };
 
             let result = apply_documents_addition(
                 writer,
@@ -147,7 +152,7 @@ pub fn update_task(writer: &mut zlmdb::RwTxn, index: store::Index) -> MResult<Op
             );
 
             (update_type, result, start.elapsed())
-        },
+        }
         Update::DocumentsDeletion(documents) => {
             let start = Instant::now();
 
@@ -156,7 +161,9 @@ pub fn update_task(writer: &mut zlmdb::RwTxn, index: store::Index) -> MResult<Op
                 None => RankedMap::default(),
             };
 
-            let update_type = UpdateType::DocumentsDeletion { number: documents.len() };
+            let update_type = UpdateType::DocumentsDeletion {
+                number: documents.len(),
+            };
 
             let result = apply_documents_deletion(
                 writer,
@@ -170,38 +177,35 @@ pub fn update_task(writer: &mut zlmdb::RwTxn, index: store::Index) -> MResult<Op
             );
 
             (update_type, result, start.elapsed())
-        },
+        }
         Update::SynonymsAddition(synonyms) => {
             let start = Instant::now();
 
-            let update_type = UpdateType::SynonymsAddition { number: synonyms.len() };
+            let update_type = UpdateType::SynonymsAddition {
+                number: synonyms.len(),
+            };
 
-            let result = apply_synonyms_addition(
-                writer,
-                index.main,
-                index.synonyms,
-                synonyms,
-            );
+            let result = apply_synonyms_addition(writer, index.main, index.synonyms, synonyms);
 
             (update_type, result, start.elapsed())
-        },
+        }
         Update::SynonymsDeletion(synonyms) => {
             let start = Instant::now();
 
-            let update_type = UpdateType::SynonymsDeletion { number: synonyms.len() };
+            let update_type = UpdateType::SynonymsDeletion {
+                number: synonyms.len(),
+            };
 
-            let result = apply_synonyms_deletion(
-                writer,
-                index.main,
-                index.synonyms,
-                synonyms,
-            );
+            let result = apply_synonyms_deletion(writer, index.main, index.synonyms, synonyms);
 
             (update_type, result, start.elapsed())
-        },
+        }
     };
 
-    debug!("Processed update number {} {:?} {:?}", update_id, update_type, result);
+    debug!(
+        "Processed update number {} {:?} {:?}",
+        update_id, update_type, result
+    );
 
     let detailed_duration = DetailedDuration { main: duration };
     let status = UpdateResult {
@@ -211,7 +215,9 @@ pub fn update_task(writer: &mut zlmdb::RwTxn, index: store::Index) -> MResult<Op
         detailed_duration,
     };
 
-    index.updates_results.put_update_result(writer, update_id, &status)?;
+    index
+        .updates_results
+        .put_update_result(writer, update_id, &status)?;
 
     Ok(Some(status))
 }
diff --git a/meilidb-core/src/update/schema_update.rs b/meilidb-core/src/update/schema_update.rs
index e544e1fcf..13fdab507 100644
--- a/meilidb-core/src/update/schema_update.rs
+++ b/meilidb-core/src/update/schema_update.rs
@@ -1,18 +1,19 @@
+use crate::update::{next_update_id, Update};
+use crate::{error::UnsupportedOperation, store, MResult};
 use meilidb_schema::Schema;
-use crate::{store, error::UnsupportedOperation, MResult};
-use crate::update::{Update, next_update_id};
 
 pub fn apply_schema_update(
     writer: &mut zlmdb::RwTxn,
     main_store: store::Main,
     new_schema: &Schema,
-) -> MResult<()>
-{
+) -> MResult<()> {
     if let Some(_) = main_store.schema(writer)? {
-        return Err(UnsupportedOperation::SchemaAlreadyExists.into())
+        return Err(UnsupportedOperation::SchemaAlreadyExists.into());
     }
 
-    main_store.put_schema(writer, new_schema).map_err(Into::into)
+    main_store
+        .put_schema(writer, new_schema)
+        .map_err(Into::into)
 }
 
 pub fn push_schema_update(
@@ -20,8 +21,7 @@ pub fn push_schema_update(
     updates_store: store::Updates,
     updates_results_store: store::UpdatesResults,
     schema: Schema,
-) -> MResult<u64>
-{
+) -> MResult<u64> {
     let last_update_id = next_update_id(writer, updates_store, updates_results_store)?;
 
     let update = Update::Schema(schema);
diff --git a/meilidb-core/src/update/synonyms_addition.rs b/meilidb-core/src/update/synonyms_addition.rs
index d6219eac6..f32475a1e 100644
--- a/meilidb-core/src/update/synonyms_addition.rs
+++ b/meilidb-core/src/update/synonyms_addition.rs
@@ -1,10 +1,10 @@
 use std::collections::BTreeMap;
 
-use fst::{SetBuilder, set::OpBuilder};
+use fst::{set::OpBuilder, SetBuilder};
 use sdset::SetBuf;
 
 use crate::automaton::normalize_str;
-use crate::update::{Update, next_update_id};
+use crate::update::{next_update_id, Update};
 use crate::{store, MResult};
 
 pub struct SynonymsAddition {
@@ -19,8 +19,7 @@ impl SynonymsAddition {
         updates_store: store::Updates,
         updates_results_store: store::UpdatesResults,
         updates_notifier: crossbeam_channel::Sender<()>,
-    ) -> SynonymsAddition
-    {
+    ) -> SynonymsAddition {
         SynonymsAddition {
             updates_store,
             updates_results_store,
@@ -30,13 +29,17 @@ impl SynonymsAddition {
     }
 
     pub fn add_synonym<S, T, I>(&mut self, synonym: S, alternatives: I)
-    where S: AsRef<str>,
-          T: AsRef<str>,
-          I: IntoIterator<Item=T>,
+    where
+        S: AsRef<str>,
+        T: AsRef<str>,
+        I: IntoIterator<Item = T>,
     {
         let synonym = normalize_str(synonym.as_ref());
         let alternatives = alternatives.into_iter().map(|s| s.as_ref().to_lowercase());
-        self.synonyms.entry(synonym).or_insert_with(Vec::new).extend(alternatives);
+        self.synonyms
+            .entry(synonym)
+            .or_insert_with(Vec::new)
+            .extend(alternatives);
     }
 
     pub fn finalize(self, writer: &mut zlmdb::RwTxn) -> MResult<u64> {
@@ -56,8 +59,7 @@ pub fn push_synonyms_addition(
     updates_store: store::Updates,
     updates_results_store: store::UpdatesResults,
     addition: BTreeMap<String, Vec<String>>,
-) -> MResult<u64>
-{
+) -> MResult<u64> {
     let last_update_id = next_update_id(writer, updates_store, updates_results_store)?;
 
     let update = Update::SynonymsAddition(addition);
@@ -71,8 +73,7 @@ pub fn apply_synonyms_addition(
     main_store: store::Main,
     synonyms_store: store::Synonyms,
     addition: BTreeMap<String, Vec<String>>,
-) -> MResult<()>
-{
+) -> MResult<()> {
     let mut synonyms_builder = SetBuilder::memory();
 
     for (word, alternatives) in addition {
@@ -107,7 +108,7 @@ pub fn apply_synonyms_addition(
                 .into_inner()
                 .and_then(fst::Set::from_bytes)
                 .unwrap()
-        },
+        }
         None => delta_synonyms,
     };
 
diff --git a/meilidb-core/src/update/synonyms_deletion.rs b/meilidb-core/src/update/synonyms_deletion.rs
index 43fc848ee..c498c3ab0 100644
--- a/meilidb-core/src/update/synonyms_deletion.rs
+++ b/meilidb-core/src/update/synonyms_deletion.rs
@@ -1,11 +1,11 @@
 use std::collections::BTreeMap;
 use std::iter::FromIterator;
 
-use fst::{SetBuilder, set::OpBuilder};
+use fst::{set::OpBuilder, SetBuilder};
 use sdset::SetBuf;
 
 use crate::automaton::normalize_str;
-use crate::update::{Update, next_update_id};
+use crate::update::{next_update_id, Update};
 use crate::{store, MResult};
 
 pub struct SynonymsDeletion {
@@ -20,8 +20,7 @@ impl SynonymsDeletion {
         updates_store: store::Updates,
         updates_results_store: store::UpdatesResults,
         updates_notifier: crossbeam_channel::Sender<()>,
-    ) -> SynonymsDeletion
-    {
+    ) -> SynonymsDeletion {
         SynonymsDeletion {
             updates_store,
             updates_results_store,
@@ -36,9 +35,10 @@ impl SynonymsDeletion {
     }
 
     pub fn delete_specific_alternatives_of<S, T, I>(&mut self, synonym: S, alternatives: I)
-    where S: AsRef<str>,
-          T: AsRef<str>,
-          I: Iterator<Item=T>,
+    where
+        S: AsRef<str>,
+        T: AsRef<str>,
+        I: Iterator<Item = T>,
     {
         let synonym = normalize_str(synonym.as_ref());
         let value = self.synonyms.entry(synonym).or_insert(None);
@@ -66,8 +66,7 @@ pub fn push_synonyms_deletion(
     updates_store: store::Updates,
     updates_results_store: store::UpdatesResults,
     deletion: BTreeMap<String, Option<Vec<String>>>,
-) -> MResult<u64>
-{
+) -> MResult<u64> {
     let last_update_id = next_update_id(writer, updates_store, updates_results_store)?;
 
     let update = Update::SynonymsDeletion(deletion);
@@ -81,8 +80,7 @@ pub fn apply_synonyms_deletion(
     main_store: store::Main,
     synonyms_store: store::Synonyms,
     deletion: BTreeMap<String, Option<Vec<String>>>,
-) -> MResult<()>
-{
+) -> MResult<()> {
     let mut delete_whole_synonym_builder = SetBuilder::memory();
 
     for (synonym, alternatives) in deletion {
@@ -98,9 +96,7 @@ pub fn apply_synonyms_deletion(
                     let alternatives = SetBuf::from_dirty(alternatives);
                     let mut builder = SetBuilder::memory();
                     builder.extend_iter(alternatives).unwrap();
-                    builder.into_inner()
-                        .and_then(fst::Set::from_bytes)
-                        .unwrap()
+                    builder.into_inner().and_then(fst::Set::from_bytes).unwrap()
                 };
 
                 let op = OpBuilder::new()
@@ -124,7 +120,7 @@ pub fn apply_synonyms_deletion(
                 } else {
                     synonyms_store.put_synonyms(writer, synonym.as_bytes(), &alternatives)?;
                 }
-            },
+            }
             None => {
                 delete_whole_synonym_builder.insert(&synonym).unwrap();
                 synonyms_store.del_synonyms(writer, synonym.as_bytes())?;
@@ -150,7 +146,7 @@ pub fn apply_synonyms_deletion(
                 .into_inner()
                 .and_then(fst::Set::from_bytes)
                 .unwrap()
-        },
+        }
         None => fst::Set::default(),
     };
 
diff --git a/meilidb-schema/src/lib.rs b/meilidb-schema/src/lib.rs
index 5109b33e1..0a32a8f2d 100644
--- a/meilidb-schema/src/lib.rs
+++ b/meilidb-schema/src/lib.rs
@@ -1,14 +1,26 @@
-use std::collections::{HashMap, BTreeMap};
-use std::{fmt, u16};
+use std::collections::{BTreeMap, HashMap};
 use std::ops::BitOr;
 use std::sync::Arc;
+use std::{fmt, u16};
 
-use serde::{Serialize, Deserialize};
 use indexmap::IndexMap;
+use serde::{Deserialize, Serialize};
 
-pub const DISPLAYED: SchemaProps = SchemaProps { displayed: true,  indexed: false, ranked: false };
-pub const INDEXED: SchemaProps   = SchemaProps { displayed: false, indexed: true,  ranked: false };
-pub const RANKED: SchemaProps    = SchemaProps { displayed: false, indexed: false, ranked: true  };
+pub const DISPLAYED: SchemaProps = SchemaProps {
+    displayed: true,
+    indexed: false,
+    ranked: false,
+};
+pub const INDEXED: SchemaProps = SchemaProps {
+    displayed: false,
+    indexed: true,
+    ranked: false,
+};
+pub const RANKED: SchemaProps = SchemaProps {
+    displayed: false,
+    indexed: false,
+    ranked: true,
+};
 
 #[derive(Debug, Copy, Clone, PartialEq, Eq, Serialize, Deserialize)]
 pub struct SchemaProps {
@@ -80,7 +92,13 @@ impl SchemaBuilder {
         }
 
         let identifier = self.identifier;
-        Schema { inner: Arc::new(InnerSchema { identifier, attrs, props }) }
+        Schema {
+            inner: Arc::new(InnerSchema {
+                identifier,
+                attrs,
+                props,
+            }),
+        }
     }
 }
 
@@ -100,7 +118,10 @@ impl Schema {
     fn to_builder(&self) -> SchemaBuilder {
         let identifier = self.inner.identifier.clone();
         let attributes = self.attributes_ordered();
-        SchemaBuilder { identifier, attributes }
+        SchemaBuilder {
+            identifier,
+            attributes,
+        }
     }
 
     fn attributes_ordered(&self) -> IndexMap<String, SchemaProps> {
@@ -136,18 +157,18 @@ impl Schema {
         name
     }
 
-    pub fn iter<'a>(&'a self) -> impl Iterator<Item=(&str, SchemaAttr, SchemaProps)> + 'a {
-        self.inner.props.iter()
-            .map(move |(name, prop)| {
-                let attr = self.inner.attrs.get(name).unwrap();
-                (name.as_str(), *attr, *prop)
-            })
+    pub fn iter<'a>(&'a self) -> impl Iterator<Item = (&str, SchemaAttr, SchemaProps)> + 'a {
+        self.inner.props.iter().map(move |(name, prop)| {
+            let attr = self.inner.attrs.get(name).unwrap();
+            (name.as_str(), *attr, *prop)
+        })
     }
 }
 
 impl Serialize for Schema {
     fn serialize<S>(&self, serializer: S) -> Result<S::Ok, S::Error>
-    where S: serde::ser::Serializer,
+    where
+        S: serde::ser::Serializer,
     {
         self.to_builder().serialize(serializer)
     }
@@ -155,15 +176,15 @@ impl Serialize for Schema {
 
 impl<'de> Deserialize<'de> for Schema {
     fn deserialize<D>(deserializer: D) -> Result<Self, D::Error>
-    where D: serde::de::Deserializer<'de>,
+    where
+        D: serde::de::Deserializer<'de>,
     {
         let builder = SchemaBuilder::deserialize(deserializer)?;
         Ok(builder.build())
     }
 }
 
-#[derive(Serialize, Deserialize)]
-#[derive(Debug, Copy, Clone, PartialOrd, Ord, PartialEq, Eq, Hash)]
+#[derive(Serialize, Deserialize, Debug, Copy, Clone, PartialOrd, Ord, PartialEq, Eq, Hash)]
 pub struct SchemaAttr(pub u16);
 
 impl SchemaAttr {
diff --git a/meilidb-tokenizer/src/lib.rs b/meilidb-tokenizer/src/lib.rs
index 3cea72ffc..bb6002fe1 100644
--- a/meilidb-tokenizer/src/lib.rs
+++ b/meilidb-tokenizer/src/lib.rs
@@ -1,17 +1,17 @@
-use std::iter::Peekable;
-use slice_group_by::StrGroupBy;
 use self::SeparatorCategory::*;
+use slice_group_by::StrGroupBy;
+use std::iter::Peekable;
 
 pub fn is_cjk(c: char) -> bool {
-    (c >= '\u{2e80}' && c <= '\u{2eff}') ||
-    (c >= '\u{2f00}' && c <= '\u{2fdf}') ||
-    (c >= '\u{3040}' && c <= '\u{309f}') ||
-    (c >= '\u{30a0}' && c <= '\u{30ff}') ||
-    (c >= '\u{3100}' && c <= '\u{312f}') ||
-    (c >= '\u{3200}' && c <= '\u{32ff}') ||
-    (c >= '\u{3400}' && c <= '\u{4dbf}') ||
-    (c >= '\u{4e00}' && c <= '\u{9fff}') ||
-    (c >= '\u{f900}' && c <= '\u{faff}')
+    (c >= '\u{2e80}' && c <= '\u{2eff}')
+        || (c >= '\u{2f00}' && c <= '\u{2fdf}')
+        || (c >= '\u{3040}' && c <= '\u{309f}')
+        || (c >= '\u{30a0}' && c <= '\u{30ff}')
+        || (c >= '\u{3100}' && c <= '\u{312f}')
+        || (c >= '\u{3200}' && c <= '\u{32ff}')
+        || (c >= '\u{3400}' && c <= '\u{4dbf}')
+        || (c >= '\u{4e00}' && c <= '\u{9fff}')
+        || (c >= '\u{f900}' && c <= '\u{faff}')
 }
 
 #[derive(Debug, Copy, Clone, PartialEq, Eq)]
@@ -22,7 +22,11 @@ enum SeparatorCategory {
 
 impl SeparatorCategory {
     fn merge(self, other: SeparatorCategory) -> SeparatorCategory {
-        if let (Soft, Soft) = (self, other) { Soft } else { Hard }
+        if let (Soft, Soft) = (self, other) {
+            Soft
+        } else {
+            Hard
+        }
     }
 
     fn to_usize(self) -> usize {
@@ -40,7 +44,7 @@ fn is_separator(c: char) -> bool {
 fn classify_separator(c: char) -> Option<SeparatorCategory> {
     match c {
         ' ' | '-' | '_' | '\'' | ':' | '"' => Some(Soft),
-        '.' | ';' | ',' | '!' | '?' |  '(' | ')' => Some(Hard),
+        '.' | ';' | ',' | '!' | '?' | '(' | ')' => Some(Hard),
         _ => None,
     }
 }
@@ -79,7 +83,7 @@ fn chars_count_index((n, _): (usize, usize), (i, c): (usize, char)) -> (usize, u
     (n + 1, i + c.len_utf8())
 }
 
-pub fn split_query_string(query: &str) -> impl Iterator<Item=&str> {
+pub fn split_query_string(query: &str) -> impl Iterator<Item = &str> {
     Tokenizer::new(query).map(|t| t.word)
 }
 
@@ -100,9 +104,10 @@ impl<'a> Tokenizer<'a> {
     pub fn new(string: &str) -> Tokenizer {
         // skip every separator and set `char_index`
         // to the number of char trimmed
-        let (count, index) = string.char_indices()
-                                   .take_while(|(_, c)| is_separator(*c))
-                                   .fold((0, 0), chars_count_index);
+        let (count, index) = string
+            .char_indices()
+            .take_while(|(_, c)| is_separator(*c))
+            .fold((0, 0), chars_count_index);
 
         Tokenizer {
             inner: &string[index..],
@@ -122,10 +127,11 @@ impl<'a> Iterator for Tokenizer<'a> {
             let (count, index) = string.char_indices().fold((0, 0), chars_count_index);
 
             if !is_str_word(string) {
-                self.word_index += string.chars()
-                                         .filter_map(classify_separator)
-                                         .fold(Soft, |a, x| a.merge(x))
-                                         .to_usize();
+                self.word_index += string
+                    .chars()
+                    .filter_map(classify_separator)
+                    .fold(Soft, |a, x| a.merge(x))
+                    .to_usize();
                 self.char_index += count;
                 self.inner = &self.inner[index..];
                 continue;
@@ -153,7 +159,8 @@ impl<'a> Iterator for Tokenizer<'a> {
 }
 
 pub struct SeqTokenizer<'a, I>
-where I: Iterator<Item=&'a str>,
+where
+    I: Iterator<Item = &'a str>,
 {
     inner: I,
     current: Option<Peekable<Tokenizer<'a>>>,
@@ -162,7 +169,8 @@ where I: Iterator<Item=&'a str>,
 }
 
 impl<'a, I> SeqTokenizer<'a, I>
-where I: Iterator<Item=&'a str>,
+where
+    I: Iterator<Item = &'a str>,
 {
     pub fn new(mut iter: I) -> SeqTokenizer<'a, I> {
         let current = iter.next().map(|s| Tokenizer::new(s).peekable());
@@ -176,7 +184,8 @@ where I: Iterator<Item=&'a str>,
 }
 
 impl<'a, I> Iterator for SeqTokenizer<'a, I>
-where I: Iterator<Item=&'a str>,
+where
+    I: Iterator<Item = &'a str>,
 {
     type Item = Token<'a>;
 
@@ -202,15 +211,15 @@ where I: Iterator<Item=&'a str>,
                         }
 
                         Some(token)
-                    },
+                    }
                     None => {
                         // no more words in this text we must
                         // start tokenizing the next text
                         self.current = self.inner.next().map(|s| Tokenizer::new(s).peekable());
                         self.next()
-                    },
+                    }
                 }
-            },
+            }
             // no more texts available
             None => None,
         }
@@ -225,12 +234,26 @@ mod tests {
     fn easy() {
         let mut tokenizer = Tokenizer::new("salut");
 
-        assert_eq!(tokenizer.next(), Some(Token { word: "salut", word_index: 0, char_index: 0 }));
+        assert_eq!(
+            tokenizer.next(),
+            Some(Token {
+                word: "salut",
+                word_index: 0,
+                char_index: 0
+            })
+        );
         assert_eq!(tokenizer.next(), None);
 
         let mut tokenizer = Tokenizer::new("yo    ");
 
-        assert_eq!(tokenizer.next(), Some(Token { word: "yo", word_index: 0, char_index: 0 }));
+        assert_eq!(
+            tokenizer.next(),
+            Some(Token {
+                word: "yo",
+                word_index: 0,
+                char_index: 0
+            })
+        );
         assert_eq!(tokenizer.next(), None);
     }
 
@@ -238,19 +261,82 @@ mod tests {
     fn hard() {
         let mut tokenizer = Tokenizer::new(" .? yo lolo. aïe (ouch)");
 
-        assert_eq!(tokenizer.next(), Some(Token { word: "yo", word_index: 0, char_index: 4 }));
-        assert_eq!(tokenizer.next(), Some(Token { word: "lolo", word_index: 1, char_index: 7 }));
-        assert_eq!(tokenizer.next(), Some(Token { word: "aïe", word_index: 9, char_index: 13 }));
-        assert_eq!(tokenizer.next(), Some(Token { word: "ouch", word_index: 17, char_index: 18 }));
+        assert_eq!(
+            tokenizer.next(),
+            Some(Token {
+                word: "yo",
+                word_index: 0,
+                char_index: 4
+            })
+        );
+        assert_eq!(
+            tokenizer.next(),
+            Some(Token {
+                word: "lolo",
+                word_index: 1,
+                char_index: 7
+            })
+        );
+        assert_eq!(
+            tokenizer.next(),
+            Some(Token {
+                word: "aïe",
+                word_index: 9,
+                char_index: 13
+            })
+        );
+        assert_eq!(
+            tokenizer.next(),
+            Some(Token {
+                word: "ouch",
+                word_index: 17,
+                char_index: 18
+            })
+        );
         assert_eq!(tokenizer.next(), None);
 
         let mut tokenizer = Tokenizer::new("yo ! lolo ? wtf - lol . aïe ,");
 
-        assert_eq!(tokenizer.next(), Some(Token { word: "yo", word_index: 0, char_index: 0 }));
-        assert_eq!(tokenizer.next(), Some(Token { word: "lolo", word_index: 8, char_index: 5 }));
-        assert_eq!(tokenizer.next(), Some(Token { word: "wtf", word_index: 16, char_index: 12 }));
-        assert_eq!(tokenizer.next(), Some(Token { word: "lol", word_index: 17, char_index: 18 }));
-        assert_eq!(tokenizer.next(), Some(Token { word: "aïe", word_index: 25, char_index: 24 }));
+        assert_eq!(
+            tokenizer.next(),
+            Some(Token {
+                word: "yo",
+                word_index: 0,
+                char_index: 0
+            })
+        );
+        assert_eq!(
+            tokenizer.next(),
+            Some(Token {
+                word: "lolo",
+                word_index: 8,
+                char_index: 5
+            })
+        );
+        assert_eq!(
+            tokenizer.next(),
+            Some(Token {
+                word: "wtf",
+                word_index: 16,
+                char_index: 12
+            })
+        );
+        assert_eq!(
+            tokenizer.next(),
+            Some(Token {
+                word: "lol",
+                word_index: 17,
+                char_index: 18
+            })
+        );
+        assert_eq!(
+            tokenizer.next(),
+            Some(Token {
+                word: "aïe",
+                word_index: 25,
+                char_index: 24
+            })
+        );
         assert_eq!(tokenizer.next(), None);
     }
 
@@ -258,18 +344,74 @@ mod tests {
     fn hard_long_chars() {
         let mut tokenizer = Tokenizer::new(" .? yo 😂. aïe");
 
-        assert_eq!(tokenizer.next(), Some(Token { word: "yo", word_index: 0, char_index: 4 }));
-        assert_eq!(tokenizer.next(), Some(Token { word: "😂", word_index: 1, char_index: 7 }));
-        assert_eq!(tokenizer.next(), Some(Token { word: "aïe", word_index: 9, char_index: 10 }));
+        assert_eq!(
+            tokenizer.next(),
+            Some(Token {
+                word: "yo",
+                word_index: 0,
+                char_index: 4
+            })
+        );
+        assert_eq!(
+            tokenizer.next(),
+            Some(Token {
+                word: "😂",
+                word_index: 1,
+                char_index: 7
+            })
+        );
+        assert_eq!(
+            tokenizer.next(),
+            Some(Token {
+                word: "aïe",
+                word_index: 9,
+                char_index: 10
+            })
+        );
         assert_eq!(tokenizer.next(), None);
 
         let mut tokenizer = Tokenizer::new("yo ! lolo ? 😱 - lol . 😣 ,");
 
-        assert_eq!(tokenizer.next(), Some(Token { word: "yo", word_index: 0, char_index: 0 }));
-        assert_eq!(tokenizer.next(), Some(Token { word: "lolo", word_index: 8, char_index: 5 }));
-        assert_eq!(tokenizer.next(), Some(Token { word: "😱", word_index: 16, char_index: 12 }));
-        assert_eq!(tokenizer.next(), Some(Token { word: "lol", word_index: 17, char_index: 16 }));
-        assert_eq!(tokenizer.next(), Some(Token { word: "😣", word_index: 25, char_index: 22 }));
+        assert_eq!(
+            tokenizer.next(),
+            Some(Token {
+                word: "yo",
+                word_index: 0,
+                char_index: 0
+            })
+        );
+        assert_eq!(
+            tokenizer.next(),
+            Some(Token {
+                word: "lolo",
+                word_index: 8,
+                char_index: 5
+            })
+        );
+        assert_eq!(
+            tokenizer.next(),
+            Some(Token {
+                word: "😱",
+                word_index: 16,
+                char_index: 12
+            })
+        );
+        assert_eq!(
+            tokenizer.next(),
+            Some(Token {
+                word: "lol",
+                word_index: 17,
+                char_index: 16
+            })
+        );
+        assert_eq!(
+            tokenizer.next(),
+            Some(Token {
+                word: "😣",
+                word_index: 25,
+                char_index: 22
+            })
+        );
         assert_eq!(tokenizer.next(), None);
     }
 
@@ -277,19 +419,82 @@ mod tests {
     fn hard_kanjis() {
         let mut tokenizer = Tokenizer::new("\u{2ec4}lolilol\u{2ec7}");
 
-        assert_eq!(tokenizer.next(), Some(Token { word: "\u{2ec4}", word_index: 0, char_index: 0 }));
-        assert_eq!(tokenizer.next(), Some(Token { word: "lolilol", word_index: 1, char_index: 1 }));
-        assert_eq!(tokenizer.next(), Some(Token { word: "\u{2ec7}", word_index: 2, char_index: 8 }));
+        assert_eq!(
+            tokenizer.next(),
+            Some(Token {
+                word: "\u{2ec4}",
+                word_index: 0,
+                char_index: 0
+            })
+        );
+        assert_eq!(
+            tokenizer.next(),
+            Some(Token {
+                word: "lolilol",
+                word_index: 1,
+                char_index: 1
+            })
+        );
+        assert_eq!(
+            tokenizer.next(),
+            Some(Token {
+                word: "\u{2ec7}",
+                word_index: 2,
+                char_index: 8
+            })
+        );
         assert_eq!(tokenizer.next(), None);
 
         let mut tokenizer = Tokenizer::new("\u{2ec4}\u{2ed3}\u{2ef2} lolilol - hello    \u{2ec7}");
 
-        assert_eq!(tokenizer.next(), Some(Token { word: "\u{2ec4}", word_index: 0, char_index: 0 }));
-        assert_eq!(tokenizer.next(), Some(Token { word: "\u{2ed3}", word_index: 1, char_index: 1 }));
-        assert_eq!(tokenizer.next(), Some(Token { word: "\u{2ef2}", word_index: 2, char_index: 2 }));
-        assert_eq!(tokenizer.next(), Some(Token { word: "lolilol", word_index: 3, char_index: 4 }));
-        assert_eq!(tokenizer.next(), Some(Token { word: "hello", word_index: 4, char_index: 14 }));
-        assert_eq!(tokenizer.next(), Some(Token { word: "\u{2ec7}", word_index: 5, char_index: 23 }));
+        assert_eq!(
+            tokenizer.next(),
+            Some(Token {
+                word: "\u{2ec4}",
+                word_index: 0,
+                char_index: 0
+            })
+        );
+        assert_eq!(
+            tokenizer.next(),
+            Some(Token {
+                word: "\u{2ed3}",
+                word_index: 1,
+                char_index: 1
+            })
+        );
+        assert_eq!(
+            tokenizer.next(),
+            Some(Token {
+                word: "\u{2ef2}",
+                word_index: 2,
+                char_index: 2
+            })
+        );
+        assert_eq!(
+            tokenizer.next(),
+            Some(Token {
+                word: "lolilol",
+                word_index: 3,
+                char_index: 4
+            })
+        );
+        assert_eq!(
+            tokenizer.next(),
+            Some(Token {
+                word: "hello",
+                word_index: 4,
+                char_index: 14
+            })
+        );
+        assert_eq!(
+            tokenizer.next(),
+            Some(Token {
+                word: "\u{2ec7}",
+                word_index: 5,
+                char_index: 23
+            })
+        );
         assert_eq!(tokenizer.next(), None);
     }
 }