Move StrRefCodec and ByteSliceRefCodec to their own files

milli/Cargo.toml

@@ -57,7 +57,7 @@ md5 = "0.7.0"
 rand = {version = "0.8.5", features = ["small_rng"] }
 
 [target.'cfg(fuzzing)'.dev-dependencies]
-fuzzcheck = { git = "https://github.com/loiclec/fuzzcheck-rs", branch = "main" }
+fuzzcheck = { git = "https://github.com/loiclec/fuzzcheck-rs", branch = "main" } # TODO: use released version
 
 [features]
 default = [ "charabia/default" ]

milli/src/heed_codec/byte_slice_ref.rs

@@ -0,0 +1,23 @@
+use std::borrow::Cow;
+
+use heed::{BytesDecode, BytesEncode};
+
+/// A codec for values of type `&[u8]`. Unlike `ByteSlice`, its `EItem` and `DItem` associated
+/// types are equivalent (= `&'a [u8]`) and these values can reside within another structure.
+pub struct ByteSliceRefCodec;
+
+impl<'a> BytesEncode<'a> for ByteSliceRefCodec {
+    type EItem = &'a [u8];
+
+    fn bytes_encode(item: &'a Self::EItem) -> Option<Cow<'a, [u8]>> {
+        Some(Cow::Borrowed(item))
+    }
+}
+
+impl<'a> BytesDecode<'a> for ByteSliceRefCodec {
+    type DItem = &'a [u8];
+
+    fn bytes_decode(bytes: &'a [u8]) -> Option<Self::DItem> {
+        Some(bytes)
+    }
+}

milli/src/heed_codec/facet/mod.rs

@@ -1,6 +1,5 @@
 mod field_doc_id_facet_codec;
 mod ordered_f64_codec;
-mod str_ref;
 
 use std::borrow::Cow;
 use std::convert::TryFrom;
@@ -12,9 +11,10 @@ use roaring::RoaringBitmap;
 
 pub use self::field_doc_id_facet_codec::FieldDocIdFacetCodec;
 pub use self::ordered_f64_codec::OrderedF64Codec;
-pub use self::str_ref::StrRefCodec;
 use crate::{CboRoaringBitmapCodec, BEU16};
 
+use super::StrRefCodec;
+
 pub type FieldDocIdFacetF64Codec = FieldDocIdFacetCodec<OrderedF64Codec>;
 pub type FieldDocIdFacetStringCodec = FieldDocIdFacetCodec<StrRefCodec>;
 pub type FieldDocIdFacetIgnoreCodec = FieldDocIdFacetCodec<DecodeIgnore>;
@@ -33,7 +33,7 @@ pub fn try_split_at(slice: &[u8], mid: usize) -> Option<(&[u8], &[u8])> {
 
 /// The key in the [`facet_id_string_docids` and `facet_id_f64_docids`][`Index::facet_id_string_docids`]
 /// databases.
-#[derive(Debug, Clone, Copy, PartialEq, Eq, PartialOrd, Ord)]
+#[derive(Debug, Clone, Copy, PartialEq, Eq, PartialOrd, Ord)] // TODO: try removing PartialOrd and Ord
 pub struct FacetGroupKey<T> {
     pub field_id: u16,
     pub level: u8,
@@ -103,23 +103,3 @@ impl<'a> heed::BytesDecode<'a> for FacetGroupValueCodec {
         Some(FacetGroupValue { size, bitmap })
     }
 }
-
-/// A codec for values of type `&[u8]`. Unlike `ByteSlice`, its `EItem` and `DItem` associated
-/// types are equivalent (= `&'a [u8]`) and these values can reside within another structure.
-pub struct ByteSliceRef;
-
-impl<'a> BytesEncode<'a> for ByteSliceRef {
-    type EItem = &'a [u8];
-
-    fn bytes_encode(item: &'a Self::EItem) -> Option<Cow<'a, [u8]>> {
-        Some(Cow::Borrowed(item))
-    }
-}
-
-impl<'a> BytesDecode<'a> for ByteSliceRef {
-    type DItem = &'a [u8];
-
-    fn bytes_decode(bytes: &'a [u8]) -> Option<Self::DItem> {
-        Some(bytes)
-    }
-}

milli/src/heed_codec/mod.rs

@@ -1,10 +1,12 @@
 mod beu32_str_codec;
+mod byte_slice_ref;
 pub mod facet;
 mod field_id_word_count_codec;
 mod obkv_codec;
 mod roaring_bitmap;
 mod roaring_bitmap_length;
 mod str_beu32_codec;
+mod str_ref;
 mod str_str_u8_codec;
 
 pub use self::beu32_str_codec::BEU32StrCodec;
@@ -16,3 +18,5 @@ pub use self::roaring_bitmap_length::{
 };
 pub use self::str_beu32_codec::StrBEU32Codec;
 pub use self::str_str_u8_codec::{U8StrStrCodec, UncheckedU8StrStrCodec};
+pub use byte_slice_ref::ByteSliceRefCodec;
+pub use str_ref::StrRefCodec;

milli/src/index.rs

@@ -16,8 +16,9 @@ use crate::facet::FacetType;
 use crate::fields_ids_map::FieldsIdsMap;
 use crate::heed_codec::facet::{
     FacetGroupKeyCodec, FacetGroupValueCodec, FieldDocIdFacetF64Codec, FieldDocIdFacetStringCodec,
-    FieldIdCodec, OrderedF64Codec, StrRefCodec,
+    FieldIdCodec, OrderedF64Codec,
 };
+use crate::heed_codec::StrRefCodec;
 use crate::{
     default_criteria, BEU32StrCodec, BoRoaringBitmapCodec, CboRoaringBitmapCodec, Criterion,
     DocumentId, ExternalDocumentsIds, FacetDistribution, FieldDistribution, FieldId,

milli/src/search/criteria/asc_desc.rs

@@ -7,7 +7,8 @@ use roaring::RoaringBitmap;
 
 use super::{Criterion, CriterionParameters, CriterionResult};
 use crate::facet::FacetType;
-use crate::heed_codec::facet::{ByteSliceRef, FacetGroupKeyCodec};
+use crate::heed_codec::facet::FacetGroupKeyCodec;
+use crate::heed_codec::ByteSliceRefCodec;
 use crate::search::criteria::{resolve_query_tree, CriteriaBuilder};
 use crate::search::facet::{ascending_facet_sort, descending_facet_sort};
 use crate::search::query_tree::Operation;
@@ -194,14 +195,14 @@ fn facet_ordered<'t>(
 
         let number_iter = make_iter(
             rtxn,
-            index.facet_id_f64_docids.remap_key_type::<FacetGroupKeyCodec<ByteSliceRef>>(),
+            index.facet_id_f64_docids.remap_key_type::<FacetGroupKeyCodec<ByteSliceRefCodec>>(),
             field_id,
             candidates.clone(),
         )?;
 
         let string_iter = make_iter(
             rtxn,
-            index.facet_id_string_docids.remap_key_type::<FacetGroupKeyCodec<ByteSliceRef>>(),
+            index.facet_id_string_docids.remap_key_type::<FacetGroupKeyCodec<ByteSliceRefCodec>>(),
             field_id,
             candidates,
         )?;

milli/src/search/facet/facet_distribution.rs

@@ -9,9 +9,10 @@ use roaring::RoaringBitmap;
 use crate::error::UserError;
 use crate::facet::FacetType;
 use crate::heed_codec::facet::{
-    ByteSliceRef, FacetGroupKeyCodec, FacetGroupValueCodec, FieldDocIdFacetF64Codec,
+    FacetGroupKeyCodec, FacetGroupValueCodec, FieldDocIdFacetF64Codec, FieldDocIdFacetStringCodec,
-    FieldDocIdFacetStringCodec, OrderedF64Codec, StrRefCodec,
+    OrderedF64Codec,
 };
+use crate::heed_codec::{ByteSliceRefCodec, StrRefCodec};
 use crate::search::facet::facet_distribution_iter;
 use crate::{FieldId, Index, Result};
 
@@ -137,7 +138,9 @@ impl<'a> FacetDistribution<'a> {
     ) -> heed::Result<()> {
         facet_distribution_iter::iterate_over_facet_distribution(
             self.rtxn,
-            self.index.facet_id_f64_docids.remap_key_type::<FacetGroupKeyCodec<ByteSliceRef>>(),
+            self.index
+                .facet_id_f64_docids
+                .remap_key_type::<FacetGroupKeyCodec<ByteSliceRefCodec>>(),
             field_id,
             candidates,
             |facet_key, nbr_docids, _| {
@@ -160,7 +163,9 @@ impl<'a> FacetDistribution<'a> {
     ) -> heed::Result<()> {
         facet_distribution_iter::iterate_over_facet_distribution(
             self.rtxn,
-            self.index.facet_id_string_docids.remap_key_type::<FacetGroupKeyCodec<ByteSliceRef>>(),
+            self.index
+                .facet_id_string_docids
+                .remap_key_type::<FacetGroupKeyCodec<ByteSliceRefCodec>>(),
             field_id,
             candidates,
             |facet_key, nbr_docids, any_docid| {

milli/src/search/facet/facet_distribution_iter.rs

@@ -4,9 +4,8 @@ use heed::Result;
 use roaring::RoaringBitmap;
 
 use super::{get_first_facet_value, get_highest_level};
-use crate::heed_codec::facet::{
+use crate::heed_codec::facet::{FacetGroupKey, FacetGroupKeyCodec, FacetGroupValueCodec};
-    ByteSliceRef, FacetGroupKey, FacetGroupKeyCodec, FacetGroupValueCodec,
+use crate::heed_codec::ByteSliceRefCodec;
-};
 use crate::DocumentId;
 
 /// Call the given closure on the facet distribution of the candidate documents.
@@ -22,7 +21,7 @@ use crate::DocumentId;
 /// keep iterating over the different facet values or stop.
 pub fn iterate_over_facet_distribution<'t, CB>(
     rtxn: &'t heed::RoTxn<'t>,
-    db: heed::Database<FacetGroupKeyCodec<ByteSliceRef>, FacetGroupValueCodec>,
+    db: heed::Database<FacetGroupKeyCodec<ByteSliceRefCodec>, FacetGroupValueCodec>,
     field_id: u16,
     candidates: &RoaringBitmap,
     callback: CB,
@@ -31,10 +30,13 @@ where
     CB: FnMut(&'t [u8], u64, DocumentId) -> Result<ControlFlow<()>>,
 {
     let mut fd = FacetDistribution { rtxn, db, field_id, callback };
-    let highest_level =
+    let highest_level = get_highest_level(
-        get_highest_level(rtxn, db.remap_key_type::<FacetGroupKeyCodec<ByteSliceRef>>(), field_id)?;
+        rtxn,
+        db.remap_key_type::<FacetGroupKeyCodec<ByteSliceRefCodec>>(),
+        field_id,
+    )?;
 
-    if let Some(first_bound) = get_first_facet_value::<ByteSliceRef>(rtxn, db, field_id)? {
+    if let Some(first_bound) = get_first_facet_value::<ByteSliceRefCodec>(rtxn, db, field_id)? {
         fd.iterate(candidates, highest_level, first_bound, usize::MAX)?;
         return Ok(());
     } else {
@@ -47,7 +49,7 @@ where
     CB: FnMut(&'t [u8], u64, DocumentId) -> Result<ControlFlow<()>>,
 {
     rtxn: &'t heed::RoTxn<'t>,
-    db: heed::Database<FacetGroupKeyCodec<ByteSliceRef>, FacetGroupValueCodec>,
+    db: heed::Database<FacetGroupKeyCodec<ByteSliceRefCodec>, FacetGroupValueCodec>,
     field_id: u16,
     callback: CB,
 }
@@ -72,11 +74,13 @@ where
             if key.field_id != self.field_id {
                 return Ok(ControlFlow::Break(()));
             }
+            // TODO: use real intersection and then take min()?
             let docids_in_common = value.bitmap.intersection_len(candidates);
             if docids_in_common > 0 {
+                // TODO: use min()
                 let any_docid = value.bitmap.iter().next().unwrap();
                 match (self.callback)(key.left_bound, docids_in_common, any_docid)? {
-                    ControlFlow::Continue(_) => {}
+                    ControlFlow::Continue(_) => (), // TODO use unit instead of empty scope
                     ControlFlow::Break(_) => return Ok(ControlFlow::Break(())),
                 }
             }

milli/src/search/facet/facet_range_search.rs

@@ -4,9 +4,8 @@ use heed::BytesEncode;
 use roaring::RoaringBitmap;
 
 use super::{get_first_facet_value, get_highest_level, get_last_facet_value};
-use crate::heed_codec::facet::{
+use crate::heed_codec::facet::{FacetGroupKey, FacetGroupKeyCodec, FacetGroupValueCodec};
-    ByteSliceRef, FacetGroupKey, FacetGroupKeyCodec, FacetGroupValueCodec,
+use crate::heed_codec::ByteSliceRefCodec;
-};
 use crate::Result;
 
 /// Find all the document ids for which the given field contains a value contained within
@@ -47,13 +46,16 @@ where
         }
         Bound::Unbounded => Bound::Unbounded,
     };
-    let db = db.remap_key_type::<FacetGroupKeyCodec<ByteSliceRef>>();
+    let db = db.remap_key_type::<FacetGroupKeyCodec<ByteSliceRefCodec>>();
     let mut f = FacetRangeSearch { rtxn, db, field_id, left, right, docids };
     let highest_level = get_highest_level(rtxn, db, field_id)?;
 
-    if let Some(starting_left_bound) = get_first_facet_value::<ByteSliceRef>(rtxn, db, field_id)? {
+    if let Some(starting_left_bound) =
-        let rightmost_bound =
+        get_first_facet_value::<ByteSliceRefCodec>(rtxn, db, field_id)?
-            Bound::Included(get_last_facet_value::<ByteSliceRef>(rtxn, db, field_id)?.unwrap()); // will not fail because get_first_facet_value succeeded
+    {
+        let rightmost_bound = Bound::Included(
+            get_last_facet_value::<ByteSliceRefCodec>(rtxn, db, field_id)?.unwrap(),
+        ); // will not fail because get_first_facet_value succeeded
         let group_size = usize::MAX;
         f.run(highest_level, starting_left_bound, rightmost_bound, group_size)?;
         Ok(())
@@ -65,7 +67,7 @@ where
 /// Fetch the document ids that have a facet with a value between the two given bounds
 struct FacetRangeSearch<'t, 'b, 'bitmap> {
     rtxn: &'t heed::RoTxn<'t>,
-    db: heed::Database<FacetGroupKeyCodec<ByteSliceRef>, FacetGroupValueCodec>,
+    db: heed::Database<FacetGroupKeyCodec<ByteSliceRefCodec>, FacetGroupValueCodec>,
     field_id: u16,
     left: Bound<&'b [u8]>,
     right: Bound<&'b [u8]>,

milli/src/search/facet/facet_sort_ascending.rs

@@ -3,8 +3,9 @@ use roaring::RoaringBitmap;
 
 use super::{get_first_facet_value, get_highest_level};
 use crate::heed_codec::facet::{
-    ByteSliceRef, FacetGroupKey, FacetGroupKeyCodec, FacetGroupValue, FacetGroupValueCodec,
+    FacetGroupKey, FacetGroupKeyCodec, FacetGroupValue, FacetGroupValueCodec,
 };
+use crate::heed_codec::ByteSliceRefCodec;
 
 /// Return an iterator which iterates over the given candidate documents in
 /// ascending order of their facet value for the given field id.
@@ -30,12 +31,12 @@ use crate::heed_codec::facet::{
 /// Note that once a document id is returned by the iterator, it is never returned again.
 pub fn ascending_facet_sort<'t>(
     rtxn: &'t heed::RoTxn<'t>,
-    db: heed::Database<FacetGroupKeyCodec<ByteSliceRef>, FacetGroupValueCodec>,
+    db: heed::Database<FacetGroupKeyCodec<ByteSliceRefCodec>, FacetGroupValueCodec>,
     field_id: u16,
     candidates: RoaringBitmap,
 ) -> Result<Box<dyn Iterator<Item = Result<RoaringBitmap>> + 't>> {
     let highest_level = get_highest_level(rtxn, db, field_id)?;
-    if let Some(first_bound) = get_first_facet_value::<ByteSliceRef>(rtxn, db, field_id)? {
+    if let Some(first_bound) = get_first_facet_value::<ByteSliceRefCodec>(rtxn, db, field_id)? {
         let first_key = FacetGroupKey { field_id, level: highest_level, left_bound: first_bound };
         let iter = db.range(rtxn, &(first_key..)).unwrap().take(usize::MAX);
 
@@ -47,11 +48,13 @@ pub fn ascending_facet_sort<'t>(
 
 struct AscendingFacetSort<'t, 'e> {
     rtxn: &'t heed::RoTxn<'e>,
-    db: heed::Database<FacetGroupKeyCodec<ByteSliceRef>, FacetGroupValueCodec>,
+    db: heed::Database<FacetGroupKeyCodec<ByteSliceRefCodec>, FacetGroupValueCodec>,
     field_id: u16,
     stack: Vec<(
         RoaringBitmap,
-        std::iter::Take<heed::RoRange<'t, FacetGroupKeyCodec<ByteSliceRef>, FacetGroupValueCodec>>,
+        std::iter::Take<
+            heed::RoRange<'t, FacetGroupKeyCodec<ByteSliceRefCodec>, FacetGroupValueCodec>,
+        >,
     )>,
 }
 

milli/src/search/facet/facet_sort_descending.rs

@@ -5,22 +5,23 @@ use roaring::RoaringBitmap;
 
 use super::{get_first_facet_value, get_highest_level, get_last_facet_value};
 use crate::heed_codec::facet::{
-    ByteSliceRef, FacetGroupKey, FacetGroupKeyCodec, FacetGroupValue, FacetGroupValueCodec,
+    FacetGroupKey, FacetGroupKeyCodec, FacetGroupValue, FacetGroupValueCodec,
 };
+use crate::heed_codec::ByteSliceRefCodec;
 
 /// See documentationg for [`ascending_facet_sort`](super::ascending_facet_sort).
 ///
 /// This function does the same thing, but in the opposite order.
 pub fn descending_facet_sort<'t>(
     rtxn: &'t heed::RoTxn<'t>,
-    db: heed::Database<FacetGroupKeyCodec<ByteSliceRef>, FacetGroupValueCodec>,
+    db: heed::Database<FacetGroupKeyCodec<ByteSliceRefCodec>, FacetGroupValueCodec>,
     field_id: u16,
     candidates: RoaringBitmap,
 ) -> Result<Box<dyn Iterator<Item = Result<RoaringBitmap>> + 't>> {
     let highest_level = get_highest_level(rtxn, db, field_id)?;
-    if let Some(first_bound) = get_first_facet_value::<ByteSliceRef>(rtxn, db, field_id)? {
+    if let Some(first_bound) = get_first_facet_value::<ByteSliceRefCodec>(rtxn, db, field_id)? {
         let first_key = FacetGroupKey { field_id, level: highest_level, left_bound: first_bound };
-        let last_bound = get_last_facet_value::<ByteSliceRef>(rtxn, db, field_id)?.unwrap();
+        let last_bound = get_last_facet_value::<ByteSliceRefCodec>(rtxn, db, field_id)?.unwrap();
         let last_key = FacetGroupKey { field_id, level: highest_level, left_bound: last_bound };
         let iter = db.rev_range(rtxn, &(first_key..=last_key))?.take(usize::MAX);
         Ok(Box::new(DescendingFacetSort {
@@ -36,12 +37,12 @@ pub fn descending_facet_sort<'t>(
 
 struct DescendingFacetSort<'t> {
     rtxn: &'t heed::RoTxn<'t>,
-    db: heed::Database<FacetGroupKeyCodec<ByteSliceRef>, FacetGroupValueCodec>,
+    db: heed::Database<FacetGroupKeyCodec<ByteSliceRefCodec>, FacetGroupValueCodec>,
     field_id: u16,
     stack: Vec<(
         RoaringBitmap,
         std::iter::Take<
-            heed::RoRevRange<'t, FacetGroupKeyCodec<ByteSliceRef>, FacetGroupValueCodec>,
+            heed::RoRevRange<'t, FacetGroupKeyCodec<ByteSliceRefCodec>, FacetGroupValueCodec>,
         >,
         Bound<&'t [u8]>,
     )>,
@@ -97,7 +98,7 @@ impl<'t> Iterator for DescendingFacetSort<'t> {
                     *right_bound = Bound::Excluded(left_bound);
                     let iter = match self
                         .db
-                        .remap_key_type::<FacetGroupKeyCodec<ByteSliceRef>>()
+                        .remap_key_type::<FacetGroupKeyCodec<ByteSliceRefCodec>>()
                         .rev_range(
                             &self.rtxn,
                             &(Bound::Included(starting_key_below), end_key_kelow),
@@ -121,7 +122,8 @@ impl<'t> Iterator for DescendingFacetSort<'t> {
 mod tests {
     use roaring::RoaringBitmap;
 
-    use crate::heed_codec::facet::{ByteSliceRef, FacetGroupKeyCodec};
+    use crate::heed_codec::facet::FacetGroupKeyCodec;
+    use crate::heed_codec::ByteSliceRefCodec;
     use crate::milli_snap;
     use crate::search::facet::facet_sort_descending::descending_facet_sort;
     use crate::search::facet::tests::{get_random_looking_index, get_simple_index};
@@ -134,7 +136,7 @@ mod tests {
             let txn = index.env.read_txn().unwrap();
             let candidates = (200..=300).into_iter().collect::<RoaringBitmap>();
             let mut results = String::new();
-            let db = index.content.remap_key_type::<FacetGroupKeyCodec<ByteSliceRef>>();
+            let db = index.content.remap_key_type::<FacetGroupKeyCodec<ByteSliceRefCodec>>();
             let iter = descending_facet_sort(&txn, db, 0, candidates).unwrap();
             for el in iter {
                 let docids = el.unwrap();

milli/src/search/facet/mod.rs

@@ -5,8 +5,8 @@ use heed::{BytesDecode, RoTxn};
 
 pub use self::facet_distribution::{FacetDistribution, DEFAULT_VALUES_PER_FACET};
 pub use self::filter::Filter;
-use crate::heed_codec::facet::{ByteSliceRef, FacetGroupKeyCodec, FacetGroupValueCodec};
+use crate::heed_codec::facet::{FacetGroupKeyCodec, FacetGroupValueCodec};
-
+use crate::heed_codec::ByteSliceRefCodec;
 mod facet_distribution;
 mod facet_distribution_iter;
 mod facet_range_search;
@@ -17,7 +17,7 @@ mod filter;
 /// Get the first facet value in the facet database
 pub(crate) fn get_first_facet_value<'t, BoundCodec>(
     txn: &'t RoTxn,
-    db: heed::Database<FacetGroupKeyCodec<ByteSliceRef>, FacetGroupValueCodec>,
+    db: heed::Database<FacetGroupKeyCodec<ByteSliceRefCodec>, FacetGroupValueCodec>,
     field_id: u16,
 ) -> heed::Result<Option<BoundCodec::DItem>>
 where
@@ -42,7 +42,7 @@ where
 /// Get the last facet value in the facet database
 pub(crate) fn get_last_facet_value<'t, BoundCodec>(
     txn: &'t RoTxn,
-    db: heed::Database<FacetGroupKeyCodec<ByteSliceRef>, FacetGroupValueCodec>,
+    db: heed::Database<FacetGroupKeyCodec<ByteSliceRefCodec>, FacetGroupValueCodec>,
     field_id: u16,
 ) -> heed::Result<Option<BoundCodec::DItem>>
 where
@@ -67,7 +67,7 @@ where
 /// Get the height of the highest level in the facet database
 pub(crate) fn get_highest_level<'t>(
     txn: &'t RoTxn<'t>,
-    db: heed::Database<FacetGroupKeyCodec<ByteSliceRef>, FacetGroupValueCodec>,
+    db: heed::Database<FacetGroupKeyCodec<ByteSliceRefCodec>, FacetGroupValueCodec>,
     field_id: u16,
 ) -> heed::Result<u8> {
     let field_id_prefix = &field_id.to_be_bytes();
@@ -77,7 +77,7 @@ pub(crate) fn get_highest_level<'t>(
         .next()
         .map(|el| {
             let (key, _) = el.unwrap();
-            let key = FacetGroupKeyCodec::<ByteSliceRef>::bytes_decode(key).unwrap();
+            let key = FacetGroupKeyCodec::<ByteSliceRefCodec>::bytes_decode(key).unwrap();
             key.level
         })
         .unwrap_or(0))

milli/src/update/facet/bulk.rs

@@ -11,8 +11,9 @@ use time::OffsetDateTime;
 use super::{FACET_GROUP_SIZE, FACET_MIN_LEVEL_SIZE};
 use crate::facet::FacetType;
 use crate::heed_codec::facet::{
-    ByteSliceRef, FacetGroupKey, FacetGroupKeyCodec, FacetGroupValue, FacetGroupValueCodec,
+    FacetGroupKey, FacetGroupKeyCodec, FacetGroupValue, FacetGroupValueCodec,
 };
+use crate::heed_codec::ByteSliceRefCodec;
 use crate::update::index_documents::{create_writer, writer_into_reader};
 use crate::{CboRoaringBitmapCodec, FieldId, Index, Result};
 
@@ -75,11 +76,11 @@ impl<'i> FacetsUpdateBulk<'i> {
         let Self { index, field_ids, group_size, min_level_size, facet_type, new_data } = self;
 
         let db = match facet_type {
-            FacetType::String => {
+            FacetType::String => index
-                index.facet_id_string_docids.remap_key_type::<FacetGroupKeyCodec<ByteSliceRef>>()
+                .facet_id_string_docids
-            }
+                .remap_key_type::<FacetGroupKeyCodec<ByteSliceRefCodec>>(),
             FacetType::Number => {
-                index.facet_id_f64_docids.remap_key_type::<FacetGroupKeyCodec<ByteSliceRef>>()
+                index.facet_id_f64_docids.remap_key_type::<FacetGroupKeyCodec<ByteSliceRefCodec>>()
             }
         };
 
@@ -98,7 +99,7 @@ impl<'i> FacetsUpdateBulk<'i> {
 
 /// Implementation of `FacetsUpdateBulk` that is independent of milli's `Index` type
 pub(crate) struct FacetsUpdateBulkInner<R: std::io::Read + std::io::Seek> {
-    pub db: heed::Database<FacetGroupKeyCodec<ByteSliceRef>, FacetGroupValueCodec>,
+    pub db: heed::Database<FacetGroupKeyCodec<ByteSliceRefCodec>, FacetGroupValueCodec>,
     pub new_data: Option<grenad::Reader<R>>,
     pub group_size: u8,
     pub min_level_size: u8,
@@ -216,7 +217,7 @@ impl<R: std::io::Read + std::io::Seek> FacetsUpdateBulkInner<R> {
             .db
             .as_polymorph()
             .prefix_iter::<_, ByteSlice, ByteSlice>(rtxn, level_0_prefix.as_slice())?
-            .remap_types::<FacetGroupKeyCodec<ByteSliceRef>, FacetGroupValueCodec>();
+            .remap_types::<FacetGroupKeyCodec<ByteSliceRefCodec>, FacetGroupValueCodec>();
 
         let mut left_bound: &[u8] = &[];
         let mut first_iteration_for_new_group = true;
@@ -299,7 +300,7 @@ impl<R: std::io::Read + std::io::Seek> FacetsUpdateBulkInner<R> {
                     bitmaps.drain(..).zip(left_bounds.drain(..)).zip(group_sizes.drain(..))
                 {
                     let key = FacetGroupKey { field_id, level, left_bound };
-                    let key = FacetGroupKeyCodec::<ByteSliceRef>::bytes_encode(&key)
+                    let key = FacetGroupKeyCodec::<ByteSliceRefCodec>::bytes_encode(&key)
                         .ok_or(Error::Encoding)?;
                     let value = FacetGroupValue { size: group_size, bitmap };
                     let value =
@@ -328,7 +329,7 @@ impl<R: std::io::Read + std::io::Seek> FacetsUpdateBulkInner<R> {
                 bitmaps.drain(..).zip(left_bounds.drain(..)).zip(group_sizes.drain(..))
             {
                 let key = FacetGroupKey { field_id, level, left_bound };
-                let key = FacetGroupKeyCodec::<ByteSliceRef>::bytes_encode(&key)
+                let key = FacetGroupKeyCodec::<ByteSliceRefCodec>::bytes_encode(&key)
                     .ok_or(Error::Encoding)?;
                 let value = FacetGroupValue { size: group_size, bitmap };
                 let value = FacetGroupValueCodec::bytes_encode(&value).ok_or(Error::Encoding)?;

milli/src/update/facet/delete.rs

@@ -1,7 +1,8 @@
 use super::{FACET_GROUP_SIZE, FACET_MAX_GROUP_SIZE, FACET_MIN_LEVEL_SIZE};
 use crate::{
     facet::FacetType,
-    heed_codec::facet::{ByteSliceRef, FacetGroupKey, FacetGroupKeyCodec, FacetGroupValueCodec},
+    heed_codec::facet::{FacetGroupKey, FacetGroupKeyCodec, FacetGroupValueCodec},
+    heed_codec::ByteSliceRefCodec,
     update::{FacetsUpdateBulk, FacetsUpdateIncrementalInner},
     FieldId, Index, Result,
 };
@@ -11,7 +12,7 @@ use std::collections::{HashMap, HashSet};
 
 pub struct FacetsDelete<'i, 'b> {
     index: &'i Index,
-    database: heed::Database<FacetGroupKeyCodec<ByteSliceRef>, FacetGroupValueCodec>,
+    database: heed::Database<FacetGroupKeyCodec<ByteSliceRefCodec>, FacetGroupValueCodec>,
     facet_type: FacetType,
     affected_facet_values: HashMap<FieldId, HashSet<Vec<u8>>>,
     docids_to_delete: &'b RoaringBitmap,
@@ -27,11 +28,11 @@ impl<'i, 'b> FacetsDelete<'i, 'b> {
         docids_to_delete: &'b RoaringBitmap,
     ) -> Self {
         let database = match facet_type {
-            FacetType::String => {
+            FacetType::String => index
-                index.facet_id_string_docids.remap_key_type::<FacetGroupKeyCodec<ByteSliceRef>>()
+                .facet_id_string_docids
-            }
+                .remap_key_type::<FacetGroupKeyCodec<ByteSliceRefCodec>>(),
             FacetType::Number => {
-                index.facet_id_f64_docids.remap_key_type::<FacetGroupKeyCodec<ByteSliceRef>>()
+                index.facet_id_f64_docids.remap_key_type::<FacetGroupKeyCodec<ByteSliceRefCodec>>()
             }
         };
         Self {

milli/src/update/facet/incremental.rs

@@ -7,8 +7,9 @@ use roaring::RoaringBitmap;
 
 use crate::facet::FacetType;
 use crate::heed_codec::facet::{
-    ByteSliceRef, FacetGroupKey, FacetGroupKeyCodec, FacetGroupValue, FacetGroupValueCodec,
+    FacetGroupKey, FacetGroupKeyCodec, FacetGroupValue, FacetGroupValueCodec,
 };
+use crate::heed_codec::ByteSliceRefCodec;
 use crate::search::facet::get_highest_level;
 use crate::{CboRoaringBitmapCodec, FieldId, Index, Result};
 
@@ -50,10 +51,10 @@ impl<'i> FacetsUpdateIncremental<'i> {
                 db: match facet_type {
                     FacetType::String => index
                         .facet_id_string_docids
-                        .remap_key_type::<FacetGroupKeyCodec<ByteSliceRef>>(),
+                        .remap_key_type::<FacetGroupKeyCodec<ByteSliceRefCodec>>(),
                     FacetType::Number => index
                         .facet_id_f64_docids
-                        .remap_key_type::<FacetGroupKeyCodec<ByteSliceRef>>(),
+                        .remap_key_type::<FacetGroupKeyCodec<ByteSliceRefCodec>>(),
                 },
                 group_size,
                 max_group_size,
@@ -69,7 +70,7 @@ impl<'i> FacetsUpdateIncremental<'i> {
 
         let mut cursor = self.new_data.into_cursor()?;
         while let Some((key, value)) = cursor.move_on_next()? {
-            let key = FacetGroupKeyCodec::<ByteSliceRef>::bytes_decode(key)
+            let key = FacetGroupKeyCodec::<ByteSliceRefCodec>::bytes_decode(key)
                 .ok_or(heed::Error::Encoding)?;
             let docids = CboRoaringBitmapCodec::bytes_decode(value).ok_or(heed::Error::Encoding)?;
             self.inner.insert(wtxn, key.field_id, key.left_bound, &docids)?;
@@ -87,7 +88,7 @@ impl<'i> FacetsUpdateIncremental<'i> {
 
 /// Implementation of `FacetsUpdateIncremental` that is independent of milli's `Index` type
 pub struct FacetsUpdateIncrementalInner {
-    pub db: heed::Database<FacetGroupKeyCodec<ByteSliceRef>, FacetGroupValueCodec>,
+    pub db: heed::Database<FacetGroupKeyCodec<ByteSliceRefCodec>, FacetGroupValueCodec>,
     pub group_size: u8,
     pub min_level_size: u8,
     pub max_group_size: u8,
@@ -126,7 +127,7 @@ impl FacetsUpdateIncrementalInner {
         if let Some(e) = prefix_iter.next() {
             let (key_bytes, value) = e?;
             Ok((
-                FacetGroupKeyCodec::<ByteSliceRef>::bytes_decode(&key_bytes)
+                FacetGroupKeyCodec::<ByteSliceRefCodec>::bytes_decode(&key_bytes)
                     .ok_or(Error::Encoding)?
                     .into_owned(),
                 value,
@@ -149,7 +150,7 @@ impl FacetsUpdateIncrementalInner {
                             )?;
                         let (key_bytes, value) = iter.next().unwrap()?;
                         Ok((
-                            FacetGroupKeyCodec::<ByteSliceRef>::bytes_decode(&key_bytes)
+                            FacetGroupKeyCodec::<ByteSliceRefCodec>::bytes_decode(&key_bytes)
                                 .ok_or(Error::Encoding)?
                                 .into_owned(),
                             value,
@@ -411,7 +412,7 @@ impl FacetsUpdateIncrementalInner {
             let mut values = RoaringBitmap::new();
             for _ in 0..group_size {
                 let (key_bytes, value_i) = groups_iter.next().unwrap()?;
-                let key_i = FacetGroupKeyCodec::<ByteSliceRef>::bytes_decode(&key_bytes)
+                let key_i = FacetGroupKeyCodec::<ByteSliceRefCodec>::bytes_decode(&key_bytes)
                     .ok_or(Error::Encoding)?;
 
                 if first_key.is_none() {
@@ -434,7 +435,7 @@ impl FacetsUpdateIncrementalInner {
             let mut values = RoaringBitmap::new();
             for _ in 0..nbr_leftover_elements {
                 let (key_bytes, value_i) = groups_iter.next().unwrap()?;
-                let key_i = FacetGroupKeyCodec::<ByteSliceRef>::bytes_decode(&key_bytes)
+                let key_i = FacetGroupKeyCodec::<ByteSliceRefCodec>::bytes_decode(&key_bytes)
                     .ok_or(Error::Encoding)?;
 
                 if first_key.is_none() {
@@ -616,7 +617,7 @@ impl FacetsUpdateIncrementalInner {
         while let Some(el) = iter.next() {
             let (k, _) = el?;
             to_delete.push(
-                FacetGroupKeyCodec::<ByteSliceRef>::bytes_decode(k)
+                FacetGroupKeyCodec::<ByteSliceRefCodec>::bytes_decode(k)
                     .ok_or(Error::Encoding)?
                     .into_owned(),
             );
@@ -655,7 +656,8 @@ mod tests {
     use rand::{Rng, SeedableRng};
     use roaring::RoaringBitmap;
 
-    use crate::heed_codec::facet::{OrderedF64Codec, StrRefCodec};
+    use crate::heed_codec::facet::OrderedF64Codec;
+    use crate::heed_codec::StrRefCodec;
     use crate::milli_snap;
     use crate::update::facet::tests::FacetIndex;
 
@@ -1019,6 +1021,7 @@ mod tests {
 
     // fuzz tests
 }
+
 #[cfg(all(test, fuzzing))]
 mod fuzz {
     use std::borrow::Cow;

milli/src/update/facet/mod.rs

@@ -77,7 +77,8 @@ pub const FACET_MIN_LEVEL_SIZE: u8 = 5;
 use self::incremental::FacetsUpdateIncremental;
 use super::FacetsUpdateBulk;
 use crate::facet::FacetType;
-use crate::heed_codec::facet::{ByteSliceRef, FacetGroupKeyCodec, FacetGroupValueCodec};
+use crate::heed_codec::facet::{FacetGroupKeyCodec, FacetGroupValueCodec};
+use crate::heed_codec::ByteSliceRefCodec;
 use crate::{Index, Result};
 use std::fs::File;
 
@@ -87,7 +88,7 @@ pub mod incremental;
 
 pub struct FacetsUpdate<'i> {
     index: &'i Index,
-    database: heed::Database<FacetGroupKeyCodec<ByteSliceRef>, FacetGroupValueCodec>,
+    database: heed::Database<FacetGroupKeyCodec<ByteSliceRefCodec>, FacetGroupValueCodec>,
     facet_type: FacetType,
     new_data: grenad::Reader<File>,
     group_size: u8,
@@ -97,11 +98,11 @@ pub struct FacetsUpdate<'i> {
 impl<'i> FacetsUpdate<'i> {
     pub fn new(index: &'i Index, facet_type: FacetType, new_data: grenad::Reader<File>) -> Self {
         let database = match facet_type {
-            FacetType::String => {
+            FacetType::String => index
-                index.facet_id_string_docids.remap_key_type::<FacetGroupKeyCodec<ByteSliceRef>>()
+                .facet_id_string_docids
-            }
+                .remap_key_type::<FacetGroupKeyCodec<ByteSliceRefCodec>>(),
             FacetType::Number => {
-                index.facet_id_f64_docids.remap_key_type::<FacetGroupKeyCodec<ByteSliceRef>>()
+                index.facet_id_f64_docids.remap_key_type::<FacetGroupKeyCodec<ByteSliceRefCodec>>()
             }
         };
         Self {
@@ -159,8 +160,9 @@ pub(crate) mod tests {
 
     use super::bulk::FacetsUpdateBulkInner;
     use crate::heed_codec::facet::{
-        ByteSliceRef, FacetGroupKey, FacetGroupKeyCodec, FacetGroupValue, FacetGroupValueCodec,
+        FacetGroupKey, FacetGroupKeyCodec, FacetGroupValue, FacetGroupValueCodec,
     };
+    use crate::heed_codec::ByteSliceRefCodec;
     use crate::search::facet::get_highest_level;
     use crate::snapshot_tests::display_bitmap;
     use crate::update::FacetsUpdateIncrementalInner;
@@ -173,7 +175,7 @@ pub(crate) mod tests {
             BytesEncode<'a> + BytesDecode<'a, DItem = <BoundCodec as BytesEncode<'a>>::EItem>,
     {
         pub env: Env,
-        pub content: heed::Database<FacetGroupKeyCodec<ByteSliceRef>, FacetGroupValueCodec>,
+        pub content: heed::Database<FacetGroupKeyCodec<ByteSliceRefCodec>, FacetGroupValueCodec>,
         pub group_size: Cell<u8>,
         pub min_level_size: Cell<u8>,
         pub max_group_size: Cell<u8>,
@@ -327,7 +329,7 @@ pub(crate) mod tests {
                 let left_bound_bytes = BoundCodec::bytes_encode(left_bound).unwrap().into_owned();
                 let key: FacetGroupKey<&[u8]> =
                     FacetGroupKey { field_id: *field_id, level: 0, left_bound: &left_bound_bytes };
-                let key = FacetGroupKeyCodec::<ByteSliceRef>::bytes_encode(&key).unwrap();
+                let key = FacetGroupKeyCodec::<ByteSliceRefCodec>::bytes_encode(&key).unwrap();
                 let value = CboRoaringBitmapCodec::bytes_encode(&docids).unwrap();
                 writer.insert(&key, &value).unwrap();
             }
@@ -362,7 +364,7 @@ pub(crate) mod tests {
                     .unwrap();
                 while let Some(el) = iter.next() {
                     let (key, value) = el.unwrap();
-                    let key = FacetGroupKeyCodec::<ByteSliceRef>::bytes_decode(&key).unwrap();
+                    let key = FacetGroupKeyCodec::<ByteSliceRefCodec>::bytes_decode(&key).unwrap();
 
                     let mut prefix_start_below = vec![];
                     prefix_start_below.extend_from_slice(&field_id.to_be_bytes());
@@ -379,7 +381,7 @@ pub(crate) mod tests {
                             )
                             .unwrap();
                         let (key_bytes, _) = start_below_iter.next().unwrap().unwrap();
-                        FacetGroupKeyCodec::<ByteSliceRef>::bytes_decode(&key_bytes).unwrap()
+                        FacetGroupKeyCodec::<ByteSliceRefCodec>::bytes_decode(&key_bytes).unwrap()
                     };
 
                     assert!(value.size > 0);

milli/src/update/index_documents/extract/extract_facet_string_docids.rs

@@ -4,7 +4,8 @@ use std::io;
 use heed::BytesEncode;
 
 use super::helpers::{create_sorter, sorter_into_reader, try_split_array_at, GrenadParameters};
-use crate::heed_codec::facet::{FacetGroupKey, FacetGroupKeyCodec, StrRefCodec};
+use crate::heed_codec::facet::{FacetGroupKey, FacetGroupKeyCodec};
+use crate::heed_codec::StrRefCodec;
 use crate::update::index_documents::merge_cbo_roaring_bitmaps;
 use crate::{FieldId, Result};