Return original string in facet distributions, work on facet tests

milli/src/search/facet/facet_distribution.rs

@@ -140,13 +140,13 @@ impl<'a> FacetDistribution<'a> {
             self.index.facet_id_f64_docids.remap_key_type::<FacetGroupKeyCodec<ByteSliceRef>>(),
             field_id,
             candidates,
-            |facet_key, nbr_docids| {
+            |facet_key, nbr_docids, _| {
                 let facet_key = OrderedF64Codec::bytes_decode(facet_key).unwrap();
                 distribution.insert(facet_key.to_string(), nbr_docids);
                 if distribution.len() == self.max_values_per_facet {
-                    ControlFlow::Break(())
+                    Ok(ControlFlow::Break(()))
                 } else {
-                    ControlFlow::Continue(())
+                    Ok(ControlFlow::Continue(()))
                 }
             },
         )
@@ -163,13 +163,22 @@ impl<'a> FacetDistribution<'a> {
             self.index.facet_id_string_docids.remap_key_type::<FacetGroupKeyCodec<ByteSliceRef>>(),
             field_id,
             candidates,
-            |facet_key, nbr_docids| {
+            |facet_key, nbr_docids, any_docid| {
                 let facet_key = StrRefCodec::bytes_decode(facet_key).unwrap();
-                distribution.insert(facet_key.to_string(), nbr_docids);
+
+                let key: (FieldId, _, &str) = (field_id, any_docid, facet_key);
+                let original_string = self
+                    .index
+                    .field_id_docid_facet_strings
+                    .get(self.rtxn, &key)?
+                    .unwrap()
+                    .to_owned();
+
+                distribution.insert(original_string, nbr_docids);
                 if distribution.len() == self.max_values_per_facet {
-                    ControlFlow::Break(())
+                    Ok(ControlFlow::Break(()))
                 } else {
-                    ControlFlow::Continue(())
+                    Ok(ControlFlow::Continue(()))
                 }
             },
         )
@@ -186,7 +195,8 @@ impl<'a> FacetDistribution<'a> {
         let db = self.index.facet_id_f64_docids;
         let mut prefix = vec![];
         prefix.extend_from_slice(&field_id.to_be_bytes());
-        prefix.push(0);
+        prefix.push(0); // read values from level 0 only
+
         let iter = db
             .as_polymorph()
             .prefix_iter::<_, ByteSlice, ByteSlice>(self.rtxn, prefix.as_slice())?
@@ -207,10 +217,15 @@ impl<'a> FacetDistribution<'a> {
             .prefix_iter::<_, ByteSlice, ByteSlice>(self.rtxn, prefix.as_slice())?
             .remap_types::<FacetGroupKeyCodec<StrRefCodec>, FacetGroupValueCodec>();
 
-        // TODO: get the original value of the facet somewhere (in the documents DB?)
         for result in iter {
             let (key, value) = result?;
-            distribution.insert(key.left_bound.to_owned(), value.bitmap.len());
+
+            let docid = value.bitmap.iter().next().unwrap();
+            let key: (FieldId, _, &'a str) = (field_id, docid, key.left_bound);
+            let original_string =
+                self.index.field_id_docid_facet_strings.get(self.rtxn, &key)?.unwrap().to_owned();
+
+            distribution.insert(original_string, value.bitmap.len());
             if distribution.len() == self.max_values_per_facet {
                 break;
             }
@@ -304,3 +319,217 @@ impl fmt::Debug for FacetDistribution<'_> {
             .finish()
     }
 }
+
+#[cfg(test)]
+mod tests {
+    use big_s::S;
+    use maplit::hashset;
+
+    use crate::{
+        documents::documents_batch_reader_from_objects, index::tests::TempIndex, milli_snap,
+        FacetDistribution,
+    };
+
+    #[test]
+    fn few_candidates_few_facet_values() {
+        // All the tests here avoid using the code in `facet_distribution_iter` because there aren't
+        // enough candidates.
+
+        let mut index = TempIndex::new();
+        index.index_documents_config.autogenerate_docids = true;
+
+        index
+            .update_settings(|settings| settings.set_filterable_fields(hashset! { S("colour") }))
+            .unwrap();
+
+        let documents = documents!([
+            { "colour": "Blue" },
+            { "colour": "  blue" },
+            { "colour": "RED" }
+        ]);
+
+        index.add_documents(documents).unwrap();
+
+        let txn = index.read_txn().unwrap();
+
+        let map = FacetDistribution::new(&txn, &index)
+            .facets(std::iter::once("colour"))
+            .execute()
+            .unwrap();
+
+        milli_snap!(format!("{map:?}"), @r###"{"colour": {"Blue": 2, "RED": 1}}"###);
+
+        let map = FacetDistribution::new(&txn, &index)
+            .facets(std::iter::once("colour"))
+            .candidates([0, 1, 2].iter().copied().collect())
+            .execute()
+            .unwrap();
+
+        milli_snap!(format!("{map:?}"), @r###"{"colour": {"Blue": 2, "RED": 1}}"###);
+
+        let map = FacetDistribution::new(&txn, &index)
+            .facets(std::iter::once("colour"))
+            .candidates([1, 2].iter().copied().collect())
+            .execute()
+            .unwrap();
+
+        // I think it would be fine if "  blue" was "Blue" instead.
+        // We just need to get any non-normalised string I think, even if it's not in
+        // the candidates
+        milli_snap!(format!("{map:?}"), @r###"{"colour": {"  blue": 1, "RED": 1}}"###);
+
+        let map = FacetDistribution::new(&txn, &index)
+            .facets(std::iter::once("colour"))
+            .candidates([2].iter().copied().collect())
+            .execute()
+            .unwrap();
+
+        milli_snap!(format!("{map:?}"), @r###"{"colour": {"RED": 1}}"###);
+
+        let map = FacetDistribution::new(&txn, &index)
+            .facets(std::iter::once("colour"))
+            .candidates([0, 1, 2].iter().copied().collect())
+            .max_values_per_facet(1)
+            .execute()
+            .unwrap();
+
+        milli_snap!(format!("{map:?}"), @r###"{"colour": {"Blue": 2, "RED": 1}}"###);
+    }
+
+    #[test]
+    fn many_candidates_few_facet_values() {
+        let mut index = TempIndex::new_with_map_size(4096 * 10_000);
+        index.index_documents_config.autogenerate_docids = true;
+
+        index
+            .update_settings(|settings| settings.set_filterable_fields(hashset! { S("colour") }))
+            .unwrap();
+
+        let facet_values = ["Red", "RED", " red ", "Blue", "BLUE"];
+
+        let mut documents = vec![];
+        for i in 0..10_000 {
+            let document = serde_json::json!({
+                "colour": facet_values[i % 5],
+            })
+            .as_object()
+            .unwrap()
+            .clone();
+            documents.push(document);
+        }
+
+        let documents = documents_batch_reader_from_objects(documents);
+
+        index.add_documents(documents).unwrap();
+
+        let txn = index.read_txn().unwrap();
+
+        let map = FacetDistribution::new(&txn, &index)
+            .facets(std::iter::once("colour"))
+            .execute()
+            .unwrap();
+
+        milli_snap!(format!("{map:?}"), @r###"{"colour": {"Blue": 4000, "Red": 6000}}"###);
+
+        let map = FacetDistribution::new(&txn, &index)
+            .facets(std::iter::once("colour"))
+            .max_values_per_facet(1)
+            .execute()
+            .unwrap();
+
+        milli_snap!(format!("{map:?}"), @r###"{"colour": {"Blue": 4000}}"###);
+
+        let map = FacetDistribution::new(&txn, &index)
+            .facets(std::iter::once("colour"))
+            .candidates((0..10_000).into_iter().collect())
+            .execute()
+            .unwrap();
+
+        milli_snap!(format!("{map:?}"), @r###"{"colour": {"Blue": 4000, "Red": 6000}}"###);
+
+        let map = FacetDistribution::new(&txn, &index)
+            .facets(std::iter::once("colour"))
+            .candidates((0..5_000).into_iter().collect())
+            .execute()
+            .unwrap();
+
+        milli_snap!(format!("{map:?}"), @r###"{"colour": {"Blue": 2000, "Red": 3000}}"###);
+
+        let map = FacetDistribution::new(&txn, &index)
+            .facets(std::iter::once("colour"))
+            .candidates((0..5_000).into_iter().collect())
+            .execute()
+            .unwrap();
+
+        milli_snap!(format!("{map:?}"), @r###"{"colour": {"Blue": 2000, "Red": 3000}}"###);
+
+        let map = FacetDistribution::new(&txn, &index)
+            .facets(std::iter::once("colour"))
+            .candidates((0..5_000).into_iter().collect())
+            .max_values_per_facet(1)
+            .execute()
+            .unwrap();
+
+        milli_snap!(format!("{map:?}"), @r###"{"colour": {"Blue": 2000}}"###);
+    }
+
+    #[test]
+    fn many_candidates_many_facet_values() {
+        let mut index = TempIndex::new_with_map_size(4096 * 10_000);
+        index.index_documents_config.autogenerate_docids = true;
+
+        index
+            .update_settings(|settings| settings.set_filterable_fields(hashset! { S("colour") }))
+            .unwrap();
+
+        let facet_values = (0..1000).into_iter().map(|x| format!("{x:x}")).collect::<Vec<_>>();
+
+        let mut documents = vec![];
+        for i in 0..10_000 {
+            let document = serde_json::json!({
+                "colour": facet_values[i % 1000],
+            })
+            .as_object()
+            .unwrap()
+            .clone();
+            documents.push(document);
+        }
+
+        let documents = documents_batch_reader_from_objects(documents);
+
+        index.add_documents(documents).unwrap();
+
+        let txn = index.read_txn().unwrap();
+
+        let map = FacetDistribution::new(&txn, &index)
+            .facets(std::iter::once("colour"))
+            .execute()
+            .unwrap();
+
+        milli_snap!(format!("{map:?}"), "no_candidates", @"ac9229ed5964d893af96a7076e2f8af5");
+
+        let map = FacetDistribution::new(&txn, &index)
+            .facets(std::iter::once("colour"))
+            .max_values_per_facet(2)
+            .execute()
+            .unwrap();
+
+        milli_snap!(format!("{map:?}"), "no_candidates_with_max_2", @r###"{"colour": {"0": 10, "1": 10}}"###);
+
+        let map = FacetDistribution::new(&txn, &index)
+            .facets(std::iter::once("colour"))
+            .candidates((0..10_000).into_iter().collect())
+            .execute()
+            .unwrap();
+
+        milli_snap!(format!("{map:?}"), "candidates_0_10_000", @"ac9229ed5964d893af96a7076e2f8af5");
+
+        let map = FacetDistribution::new(&txn, &index)
+            .facets(std::iter::once("colour"))
+            .candidates((0..5_000).into_iter().collect())
+            .execute()
+            .unwrap();
+
+        milli_snap!(format!("{map:?}"), "candidates_0_5_000", @"825f23a4090d05756f46176987b7d992");
+    }
+}

milli/src/search/facet/facet_distribution_iter.rs

@@ -4,8 +4,9 @@ use heed::Result;
 use roaring::RoaringBitmap;
 
 use super::{get_first_facet_value, get_highest_level};
-use crate::heed_codec::facet::{
+use crate::{
-    ByteSliceRef, FacetGroupKey, FacetGroupKeyCodec, FacetGroupValueCodec,
+    heed_codec::facet::{ByteSliceRef, FacetGroupKey, FacetGroupKeyCodec, FacetGroupValueCodec},
+    DocumentId,
 };
 
 pub fn iterate_over_facet_distribution<'t, CB>(
@@ -16,7 +17,7 @@ pub fn iterate_over_facet_distribution<'t, CB>(
     callback: CB,
 ) -> Result<()>
 where
-    CB: FnMut(&'t [u8], u64) -> ControlFlow<()>,
+    CB: FnMut(&'t [u8], u64, DocumentId) -> Result<ControlFlow<()>>,
 {
     let mut fd = FacetDistribution { rtxn, db, field_id, callback };
     let highest_level =
@@ -32,7 +33,7 @@ where
 
 struct FacetDistribution<'t, CB>
 where
-    CB: FnMut(&'t [u8], u64) -> ControlFlow<()>,
+    CB: FnMut(&'t [u8], u64, DocumentId) -> Result<ControlFlow<()>>,
 {
     rtxn: &'t heed::RoTxn<'t>,
     db: heed::Database<FacetGroupKeyCodec<ByteSliceRef>, FacetGroupValueCodec>,
@@ -42,7 +43,7 @@ where
 
 impl<'t, CB> FacetDistribution<'t, CB>
 where
-    CB: FnMut(&'t [u8], u64) -> ControlFlow<()>,
+    CB: FnMut(&'t [u8], u64, DocumentId) -> Result<ControlFlow<()>>,
 {
     fn iterate_level_0(
         &mut self,
@@ -62,7 +63,8 @@ where
             }
             let docids_in_common = value.bitmap.intersection_len(candidates);
             if docids_in_common > 0 {
-                match (self.callback)(key.left_bound, docids_in_common) {
+                let any_docid = value.bitmap.iter().next().unwrap();
+                match (self.callback)(key.left_bound, docids_in_common, any_docid)? {
                     ControlFlow::Continue(_) => {}
                     ControlFlow::Break(_) => return Ok(ControlFlow::Break(())),
                 }
@@ -112,50 +114,14 @@ where
 
 #[cfg(test)]
 mod tests {
+    use super::iterate_over_facet_distribution;
+    use crate::milli_snap;
+    use crate::search::facet::tests::get_random_looking_index;
+    use crate::{heed_codec::facet::OrderedF64Codec, search::facet::tests::get_simple_index};
+    use heed::BytesDecode;
+    use roaring::RoaringBitmap;
     use std::ops::ControlFlow;
 
-    use super::iterate_over_facet_distribution;
-    use crate::heed_codec::facet::OrderedF64Codec;
-    use crate::milli_snap;
-    use crate::update::facet::tests::FacetIndex;
-    use heed::BytesDecode;
-    use rand::{Rng, SeedableRng};
-    use roaring::RoaringBitmap;
-
-    fn get_simple_index() -> FacetIndex<OrderedF64Codec> {
-        let index = FacetIndex::<OrderedF64Codec>::new(4, 8, 5);
-        let mut txn = index.env.write_txn().unwrap();
-        for i in 0..256u16 {
-            let mut bitmap = RoaringBitmap::new();
-            bitmap.insert(i as u32);
-            index.insert(&mut txn, 0, &(i as f64), &bitmap);
-        }
-        txn.commit().unwrap();
-        index
-    }
-    fn get_random_looking_index() -> FacetIndex<OrderedF64Codec> {
-        let index = FacetIndex::<OrderedF64Codec>::new(4, 8, 5);
-        let mut txn = index.env.write_txn().unwrap();
-
-        let mut rng = rand::rngs::SmallRng::from_seed([0; 32]);
-        let keys =
-            std::iter::from_fn(|| Some(rng.gen_range(0..256))).take(128).collect::<Vec<u32>>();
-
-        for (_i, key) in keys.into_iter().enumerate() {
-            let mut bitmap = RoaringBitmap::new();
-            bitmap.insert(key);
-            bitmap.insert(key + 100);
-            index.insert(&mut txn, 0, &(key as f64), &bitmap);
-        }
-        txn.commit().unwrap();
-        index
-    }
-
-    #[test]
-    fn random_looking_index_snap() {
-        let index = get_random_looking_index();
-        milli_snap!(format!("{index}"));
-    }
     #[test]
     fn filter_distribution_all() {
         let indexes = [get_simple_index(), get_random_looking_index()];
@@ -163,11 +129,17 @@ mod tests {
             let txn = index.env.read_txn().unwrap();
             let candidates = (0..=255).into_iter().collect::<RoaringBitmap>();
             let mut results = String::new();
-            iterate_over_facet_distribution(&txn, index.content, 0, &candidates, |facet, count| {
+            iterate_over_facet_distribution(
+                &txn,
+                index.content,
+                0,
+                &candidates,
+                |facet, count, _| {
                     let facet = OrderedF64Codec::bytes_decode(facet).unwrap();
                     results.push_str(&format!("{facet}: {count}\n"));
-                ControlFlow::Continue(())
+                    Ok(ControlFlow::Continue(()))
-            })
+                },
+            )
             .unwrap();
             milli_snap!(results, i);
 
@@ -182,17 +154,23 @@ mod tests {
             let candidates = (0..=255).into_iter().collect::<RoaringBitmap>();
             let mut results = String::new();
             let mut nbr_facets = 0;
-            iterate_over_facet_distribution(&txn, index.content, 0, &candidates, |facet, count| {
+            iterate_over_facet_distribution(
+                &txn,
+                index.content,
+                0,
+                &candidates,
+                |facet, count, _| {
                     let facet = OrderedF64Codec::bytes_decode(facet).unwrap();
                     if nbr_facets == 100 {
-                    return ControlFlow::Break(());
+                        return Ok(ControlFlow::Break(()));
                     } else {
                         nbr_facets += 1;
                         results.push_str(&format!("{facet}: {count}\n"));
 
-                    ControlFlow::Continue(())
+                        Ok(ControlFlow::Continue(()))
                     }
-            })
+                },
+            )
             .unwrap();
             milli_snap!(results, i);
 

milli/src/search/facet/facet_range_search.rs

@@ -15,7 +15,8 @@ pub fn find_docids_of_facet_within_bounds<'t, BoundCodec>(
     field_id: u16,
     left: &'t Bound<<BoundCodec as BytesEncode<'t>>::EItem>,
     right: &'t Bound<<BoundCodec as BytesEncode<'t>>::EItem>,
-) -> Result<RoaringBitmap>
+    docids: &mut RoaringBitmap,
+) -> Result<()>
 where
     BoundCodec: for<'a> BytesEncode<'a>,
     for<'a> <BoundCodec as BytesEncode<'a>>::EItem: Sized,
@@ -45,16 +46,15 @@ where
         Bound::Unbounded => Bound::Unbounded,
     };
     let db = db.remap_key_type::<FacetGroupKeyCodec<ByteSliceRef>>();
-    let mut docids = RoaringBitmap::new();
+    let mut f = FacetRangeSearch { rtxn, db, field_id, left, right, docids };
-    let mut f = FacetRangeSearch { rtxn, db, field_id, left, right, docids: &mut docids };
     let highest_level = get_highest_level(rtxn, db, field_id)?;
 
     if let Some(first_bound) = get_first_facet_value::<ByteSliceRef>(rtxn, db, field_id)? {
         let last_bound = get_last_facet_value::<ByteSliceRef>(rtxn, db, field_id)?.unwrap();
         f.run(highest_level, first_bound, Bound::Included(last_bound), usize::MAX)?;
-        Ok(docids)
+        Ok(())
     } else {
-        return Ok(RoaringBitmap::new());
+        return Ok(());
     }
 }
 
@@ -255,45 +255,13 @@ impl<'t, 'b, 'bitmap> FacetRangeSearch<'t, 'b, 'bitmap> {
 
 #[cfg(test)]
 mod tests {
-    use std::ops::Bound;
-
-    use rand::{Rng, SeedableRng};
-    use roaring::RoaringBitmap;
-
     use super::find_docids_of_facet_within_bounds;
     use crate::heed_codec::facet::{FacetGroupKeyCodec, OrderedF64Codec};
     use crate::milli_snap;
+    use crate::search::facet::tests::{get_random_looking_index, get_simple_index};
     use crate::snapshot_tests::display_bitmap;
-    use crate::update::facet::tests::FacetIndex;
+    use roaring::RoaringBitmap;
-
+    use std::ops::Bound;
-    fn get_simple_index() -> FacetIndex<OrderedF64Codec> {
-        let index = FacetIndex::<OrderedF64Codec>::new(4, 8, 5);
-        let mut txn = index.env.write_txn().unwrap();
-        for i in 0..256u16 {
-            let mut bitmap = RoaringBitmap::new();
-            bitmap.insert(i as u32);
-            index.insert(&mut txn, 0, &(i as f64), &bitmap);
-        }
-        txn.commit().unwrap();
-        index
-    }
-    fn get_random_looking_index() -> FacetIndex<OrderedF64Codec> {
-        let index = FacetIndex::<OrderedF64Codec>::new(4, 8, 5);
-        let mut txn = index.env.write_txn().unwrap();
-
-        let mut rng = rand::rngs::SmallRng::from_seed([0; 32]);
-        let keys =
-            std::iter::from_fn(|| Some(rng.gen_range(0..256))).take(128).collect::<Vec<u32>>();
-
-        for (_i, key) in keys.into_iter().enumerate() {
-            let mut bitmap = RoaringBitmap::new();
-            bitmap.insert(key);
-            bitmap.insert(key + 100);
-            index.insert(&mut txn, 0, &(key as f64), &bitmap);
-        }
-        txn.commit().unwrap();
-        index
-    }
 
     #[test]
     fn random_looking_index_snap() {
@@ -310,12 +278,14 @@ mod tests {
                 let i = i as f64;
                 let start = Bound::Included(0.);
                 let end = Bound::Included(i);
-                let docids = find_docids_of_facet_within_bounds::<OrderedF64Codec>(
+                let mut docids = RoaringBitmap::new();
+                find_docids_of_facet_within_bounds::<OrderedF64Codec>(
                     &txn,
                     index.content.remap_key_type::<FacetGroupKeyCodec<OrderedF64Codec>>(),
                     0,
                     &start,
                     &end,
+                    &mut docids,
                 )
                 .unwrap();
                 results.push_str(&format!("{}\n", display_bitmap(&docids)));
@@ -326,12 +296,14 @@ mod tests {
                 let i = i as f64;
                 let start = Bound::Excluded(0.);
                 let end = Bound::Excluded(i);
-                let docids = find_docids_of_facet_within_bounds::<OrderedF64Codec>(
+                let mut docids = RoaringBitmap::new();
+                find_docids_of_facet_within_bounds::<OrderedF64Codec>(
                     &txn,
                     index.content.remap_key_type::<FacetGroupKeyCodec<OrderedF64Codec>>(),
                     0,
                     &start,
                     &end,
+                    &mut docids,
                 )
                 .unwrap();
                 results.push_str(&format!("{}\n", display_bitmap(&docids)));
@@ -352,12 +324,14 @@ mod tests {
                 let i = i as f64;
                 let start = Bound::Included(i);
                 let end = Bound::Included(255.);
-                let docids = find_docids_of_facet_within_bounds::<OrderedF64Codec>(
+                let mut docids = RoaringBitmap::new();
+                find_docids_of_facet_within_bounds::<OrderedF64Codec>(
                     &txn,
                     index.content.remap_key_type::<FacetGroupKeyCodec<OrderedF64Codec>>(),
                     0,
                     &start,
                     &end,
+                    &mut docids,
                 )
                 .unwrap();
                 results.push_str(&format!("{}\n", display_bitmap(&docids)));
@@ -371,12 +345,14 @@ mod tests {
                 let i = i as f64;
                 let start = Bound::Excluded(i);
                 let end = Bound::Excluded(255.);
-                let docids = find_docids_of_facet_within_bounds::<OrderedF64Codec>(
+                let mut docids = RoaringBitmap::new();
+                find_docids_of_facet_within_bounds::<OrderedF64Codec>(
                     &txn,
                     index.content.remap_key_type::<FacetGroupKeyCodec<OrderedF64Codec>>(),
                     0,
                     &start,
                     &end,
+                    &mut docids,
                 )
                 .unwrap();
                 results.push_str(&format!("{}\n", display_bitmap(&docids)));
@@ -399,12 +375,14 @@ mod tests {
                 let i = i as f64;
                 let start = Bound::Included(i);
                 let end = Bound::Included(255. - i);
-                let docids = find_docids_of_facet_within_bounds::<OrderedF64Codec>(
+                let mut docids = RoaringBitmap::new();
+                find_docids_of_facet_within_bounds::<OrderedF64Codec>(
                     &txn,
                     index.content.remap_key_type::<FacetGroupKeyCodec<OrderedF64Codec>>(),
                     0,
                     &start,
                     &end,
+                    &mut docids,
                 )
                 .unwrap();
                 results.push_str(&format!("{}\n", display_bitmap(&docids)));
@@ -418,12 +396,14 @@ mod tests {
                 let i = i as f64;
                 let start = Bound::Excluded(i);
                 let end = Bound::Excluded(255. - i);
-                let docids = find_docids_of_facet_within_bounds::<OrderedF64Codec>(
+                let mut docids = RoaringBitmap::new();
+                find_docids_of_facet_within_bounds::<OrderedF64Codec>(
                     &txn,
                     index.content.remap_key_type::<FacetGroupKeyCodec<OrderedF64Codec>>(),
                     0,
                     &start,
                     &end,
+                    &mut docids,
                 )
                 .unwrap();
                 results.push_str(&format!("{}\n", display_bitmap(&docids)));

milli/src/search/facet/facet_sort_ascending.rs

@@ -83,49 +83,12 @@ impl<'t, 'e> Iterator for AscendingFacetSort<'t, 'e> {
 
 #[cfg(test)]
 mod tests {
-    use rand::{Rng, SeedableRng};
-    use roaring::RoaringBitmap;
-
-    use crate::heed_codec::facet::OrderedF64Codec;
     use crate::milli_snap;
     use crate::search::facet::facet_sort_ascending::ascending_facet_sort;
+    use crate::search::facet::tests::{get_random_looking_index, get_simple_index};
     use crate::snapshot_tests::display_bitmap;
-    use crate::update::facet::tests::FacetIndex;
+    use roaring::RoaringBitmap;
 
-    fn get_simple_index() -> FacetIndex<OrderedF64Codec> {
-        let index = FacetIndex::<OrderedF64Codec>::new(4, 8, 5);
-        let mut txn = index.env.write_txn().unwrap();
-        for i in 0..256u16 {
-            let mut bitmap = RoaringBitmap::new();
-            bitmap.insert(i as u32);
-            index.insert(&mut txn, 0, &(i as f64), &bitmap);
-        }
-        txn.commit().unwrap();
-        index
-    }
-    fn get_random_looking_index() -> FacetIndex<OrderedF64Codec> {
-        let index = FacetIndex::<OrderedF64Codec>::new(4, 8, 5);
-        let mut txn = index.env.write_txn().unwrap();
-
-        let mut rng = rand::rngs::SmallRng::from_seed([0; 32]);
-        let keys =
-            std::iter::from_fn(|| Some(rng.gen_range(0..256))).take(128).collect::<Vec<u32>>();
-
-        for (_i, key) in keys.into_iter().enumerate() {
-            let mut bitmap = RoaringBitmap::new();
-            bitmap.insert(key);
-            bitmap.insert(key + 100);
-            index.insert(&mut txn, 0, &(key as f64), &bitmap);
-        }
-        txn.commit().unwrap();
-        index
-    }
-
-    #[test]
-    fn random_looking_index_snap() {
-        let index = get_random_looking_index();
-        milli_snap!(format!("{index}"));
-    }
     #[test]
     fn filter_sort() {
         let indexes = [get_simple_index(), get_random_looking_index()];

milli/src/search/facet/facet_sort_descending.rs

@@ -116,49 +116,13 @@ impl<'t> Iterator for DescendingFacetSort<'t> {
 
 #[cfg(test)]
 mod tests {
-    use rand::{Rng, SeedableRng};
+    use crate::heed_codec::facet::{ByteSliceRef, FacetGroupKeyCodec};
-    use roaring::RoaringBitmap;
-
-    use crate::heed_codec::facet::{ByteSliceRef, FacetGroupKeyCodec, OrderedF64Codec};
     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};
     use crate::snapshot_tests::display_bitmap;
-    use crate::update::facet::tests::FacetIndex;
+    use roaring::RoaringBitmap;
 
-    fn get_simple_index() -> FacetIndex<OrderedF64Codec> {
-        let index = FacetIndex::<OrderedF64Codec>::new(4, 8, 5);
-        let mut txn = index.env.write_txn().unwrap();
-        for i in 0..256u16 {
-            let mut bitmap = RoaringBitmap::new();
-            bitmap.insert(i as u32);
-            index.insert(&mut txn, 0, &(i as f64), &bitmap);
-        }
-        txn.commit().unwrap();
-        index
-    }
-    fn get_random_looking_index() -> FacetIndex<OrderedF64Codec> {
-        let index = FacetIndex::<OrderedF64Codec>::new(4, 8, 5);
-        let mut txn = index.env.write_txn().unwrap();
-
-        let mut rng = rand::rngs::SmallRng::from_seed([0; 32]);
-        let keys =
-            std::iter::from_fn(|| Some(rng.gen_range(0..256))).take(128).collect::<Vec<u32>>();
-
-        for (_i, key) in keys.into_iter().enumerate() {
-            let mut bitmap = RoaringBitmap::new();
-            bitmap.insert(key);
-            bitmap.insert(key + 100);
-            index.insert(&mut txn, 0, &(key as f64), &bitmap);
-        }
-        txn.commit().unwrap();
-        index
-    }
-
-    #[test]
-    fn random_looking_index_snap() {
-        let index = get_random_looking_index();
-        milli_snap!(format!("{index}"));
-    }
     #[test]
     fn filter_sort_descending() {
         let indexes = [get_simple_index(), get_random_looking_index()];

milli/src/search/facet/filter.rs

@@ -278,11 +278,9 @@ impl<'a> Filter<'a> {
             (Excluded(l), Included(r)) if l >= r => return Ok(()),
             (_, _) => (),
         }
-        let x = facet_range_search::find_docids_of_facet_within_bounds::<OrderedF64Codec>(
+        facet_range_search::find_docids_of_facet_within_bounds::<OrderedF64Codec>(
-            rtxn, db, field_id, &left, &right,
+            rtxn, db, field_id, &left, &right, output,
         )?;
-        // TODO: the facet range search should take a mutable roaring bitmap as argument
-        *output = x;
 
         Ok(())
     }

milli/src/search/facet/mod.rs

@@ -74,3 +74,40 @@ pub(crate) fn get_highest_level<'t>(
         })
         .unwrap_or(0))
 }
+
+#[cfg(test)]
+pub(crate) mod tests {
+    use rand::{Rng, SeedableRng};
+    use roaring::RoaringBitmap;
+
+    use crate::{heed_codec::facet::OrderedF64Codec, update::facet::tests::FacetIndex};
+
+    pub fn get_simple_index() -> FacetIndex<OrderedF64Codec> {
+        let index = FacetIndex::<OrderedF64Codec>::new(4, 8, 5);
+        let mut txn = index.env.write_txn().unwrap();
+        for i in 0..256u16 {
+            let mut bitmap = RoaringBitmap::new();
+            bitmap.insert(i as u32);
+            index.insert(&mut txn, 0, &(i as f64), &bitmap);
+        }
+        txn.commit().unwrap();
+        index
+    }
+    pub fn get_random_looking_index() -> FacetIndex<OrderedF64Codec> {
+        let index = FacetIndex::<OrderedF64Codec>::new(4, 8, 5);
+        let mut txn = index.env.write_txn().unwrap();
+
+        let mut rng = rand::rngs::SmallRng::from_seed([0; 32]);
+        let keys =
+            std::iter::from_fn(|| Some(rng.gen_range(0..256))).take(128).collect::<Vec<u32>>();
+
+        for (_i, key) in keys.into_iter().enumerate() {
+            let mut bitmap = RoaringBitmap::new();
+            bitmap.insert(key);
+            bitmap.insert(key + 100);
+            index.insert(&mut txn, 0, &(key as f64), &bitmap);
+        }
+        txn.commit().unwrap();
+        index
+    }
+}

milli/src/search/facet/snapshots/facet_distribution_iter.rs/random_looking_index_snap/random_looking_index_snap.hash.snap

@@ -1,4 +0,0 @@
----
-source: milli/src/search/facet/facet_distribution_iter.rs
----
-3256c76a7c1b768a013e78d5fa6e9ff9

milli/src/search/facet/snapshots/facet_sort_ascending.rs/random_looking_index_snap/random_looking_index_snap.hash.snap

@@ -1,4 +0,0 @@
----
-source: milli/src/search/facet/facet_sort_ascending.rs
----
-3256c76a7c1b768a013e78d5fa6e9ff9

milli/src/search/facet/snapshots/facet_sort_descending.rs/random_looking_index_snap/random_looking_index_snap.hash.snap

@@ -1,4 +0,0 @@
----
-source: milli/src/search/facet/facet_sort_descending.rs
----
-3256c76a7c1b768a013e78d5fa6e9ff9