From 7bd67543dde9599d98fd7f262668b9cc112327a4 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Cl=C3=A9ment=20Renault?= <clement@meilisearch.com>
Date: Thu, 27 Apr 2023 16:04:03 +0200
Subject: [PATCH] Support the typoTolerant.enabled parameter

---
 milli/src/search/mod.rs | 87 ++++++++++++++++++++++++++++-------------
 1 file changed, 60 insertions(+), 27 deletions(-)

diff --git a/milli/src/search/mod.rs b/milli/src/search/mod.rs
index 114ca2a04..ab7c336b4 100644
--- a/milli/src/search/mod.rs
+++ b/milli/src/search/mod.rs
@@ -283,6 +283,7 @@ impl<'a> SearchForFacetValues<'a> {
                 .into());
             }
         };
+
         let fst = match self.search_query.index.facet_id_string_fst.get(rtxn, &BEU16::new(fid))? {
             Some(fst) => fst,
             None => return Ok(vec![]),
@@ -292,37 +293,69 @@ impl<'a> SearchForFacetValues<'a> {
 
         match self.query.as_ref() {
             Some(query) => {
-                let is_prefix = true;
-                let starts = StartsWith(Str::new(get_first(query)));
-                let first = Intersection(build_dfa(query, 1, is_prefix), Complement(&starts));
-                let second_dfa = build_dfa(query, 2, is_prefix);
-                let second = Intersection(&second_dfa, &starts);
-                let automaton = Union(first, &second);
+                if self.search_query.index.authorize_typos(rtxn)? {
+                    let is_prefix = true;
+                    let starts = StartsWith(Str::new(get_first(query)));
+                    let first = Intersection(build_dfa(query, 1, is_prefix), Complement(&starts));
+                    let second_dfa = build_dfa(query, 2, is_prefix);
+                    let second = Intersection(&second_dfa, &starts);
+                    let automaton = Union(first, &second);
 
-                let mut stream = fst.search(automaton).into_stream();
-                let mut result = vec![];
-                let mut length = 0;
-                while let Some(facet_value) = stream.next() {
-                    let value = std::str::from_utf8(facet_value)?;
-                    let key = FacetGroupKey { field_id: fid, level: 0, left_bound: value };
-                    let docids = match index.facet_id_string_docids.get(rtxn, &key)? {
-                        Some(FacetGroupValue { bitmap, .. }) => bitmap,
-                        None => {
-                            error!("the facet value is missing from the facet database: {key:?}");
-                            continue;
+                    let mut stream = fst.search(automaton).into_stream();
+                    let mut result = vec![];
+                    let mut length = 0;
+                    while let Some(facet_value) = stream.next() {
+                        let value = std::str::from_utf8(facet_value)?;
+                        let key = FacetGroupKey { field_id: fid, level: 0, left_bound: value };
+                        let docids = match index.facet_id_string_docids.get(rtxn, &key)? {
+                            Some(FacetGroupValue { bitmap, .. }) => bitmap,
+                            None => {
+                                error!(
+                                    "the facet value is missing from the facet database: {key:?}"
+                                );
+                                continue;
+                            }
+                        };
+                        let count = search_candidates.intersection_len(&docids);
+                        if count != 0 {
+                            result.push(FacetValueHit { value: value.to_string(), count });
+                            length += 1;
+                        }
+                        if length >= MAX_NUMBER_OF_FACETS {
+                            break;
                         }
-                    };
-                    let count = search_candidates.intersection_len(&docids);
-                    if count != 0 {
-                        result.push(FacetValueHit { value: value.to_string(), count });
-                        length += 1;
                     }
-                    if length >= MAX_NUMBER_OF_FACETS {
-                        break;
-                    }
-                }
 
-                Ok(result)
+                    Ok(result)
+                } else {
+                    let automaton = StartsWith(Str::new(query));
+                    let mut stream = fst.search(automaton).into_stream();
+                    let mut result = vec![];
+                    let mut length = 0;
+                    while let Some(facet_value) = stream.next() {
+                        let value = std::str::from_utf8(facet_value)?;
+                        let key = FacetGroupKey { field_id: fid, level: 0, left_bound: value };
+                        let docids = match index.facet_id_string_docids.get(rtxn, &key)? {
+                            Some(FacetGroupValue { bitmap, .. }) => bitmap,
+                            None => {
+                                error!(
+                                    "the facet value is missing from the facet database: {key:?}"
+                                );
+                                continue;
+                            }
+                        };
+                        let count = search_candidates.intersection_len(&docids);
+                        if count != 0 {
+                            result.push(FacetValueHit { value: value.to_string(), count });
+                            length += 1;
+                        }
+                        if length >= MAX_NUMBER_OF_FACETS {
+                            break;
+                        }
+                    }
+
+                    Ok(result)
+                }
             }
             None => {
                 let mut stream = fst.stream();