settings_ui: Fix settings search missing results when BM25 finds partial matches (#46349)

Smit Barmase created 3 months ago

Closes #44038

BM25 results were fully replacing fuzzy results, which caused some items
to disappear from search. For example, "Show Menus" wouldn’t show up
when searching for "menu". This happened due to limitations in the
Porter stemmer used by the library. Fuzzy search matched correctly, but
its results were getting overwritten. We now merge both result sets
instead.

Release Notes:

- Fixed an issue where settings search missed some results, like "Show
Menus" when searching for "menu".

Change summary

crates/settings_ui/src/settings_ui.rs | 44 ++++++++--------------------
1 file changed, 13 insertions(+), 31 deletions(-)

Detailed changes

crates/settings_ui/src/settings_ui.rs

@@ -1818,6 +1818,7 @@ impl SettingsWindow {
             );
 
             let fuzzy_matches = fuzzy_search_task.await;
+            let bm25_matches = bm25_task.await;
 
             _ = this
                 .update(cx, |this, cx| {
@@ -1842,37 +1843,18 @@ impl SettingsWindow {
                     //     let score = fuzzy_match.score;
                     //     eprint!("# {header} :: QUERY = {query} :: SCORE = {score}\n{title}\n{description}\n\n");
                     // }
-                    update_matches_inner(
-                        this,
-                        search_index.as_ref(),
-                        fuzzy_matches
-                            .into_iter()
-                            // MAGIC NUMBER: Was found to have right balance between not too many weird matches, but also
-                            // flexible enough to catch misspellings and <4 letter queries
-                            // More flexible is good for us here because fuzzy matches will only be used for things that don't
-                            // match using bm25
-                            .take_while(|fuzzy_match| fuzzy_match.score >= 0.3)
-                            .map(|fuzzy_match| fuzzy_match.candidate_id),
-                        cx,
-                    );
-                })
-                .ok();
-
-            let bm25_matches = bm25_task.await;
-
-            _ = this
-                .update(cx, |this, cx| {
-                    if bm25_matches.is_empty() {
-                        return;
-                    }
-                    update_matches_inner(
-                        this,
-                        search_index.as_ref(),
-                        bm25_matches
-                            .into_iter()
-                            .map(|bm25_match| bm25_match.document.id),
-                        cx,
-                    );
+                    let fuzzy_indices = fuzzy_matches
+                        .into_iter()
+                        // MAGIC NUMBER: Was found to have right balance between not too many weird matches, but also
+                        // flexible enough to catch misspellings and <4 letter queries
+                        .take_while(|fuzzy_match| fuzzy_match.score >= 0.5)
+                        .map(|fuzzy_match| fuzzy_match.candidate_id);
+                    let bm25_indices = bm25_matches
+                        .into_iter()
+                        .map(|bm25_match| bm25_match.document.id);
+                    let merged_indices = bm25_indices.chain(fuzzy_indices);
+
+                    update_matches_inner(this, search_index.as_ref(), merged_indices, cx);
                 })
                 .ok();