From 0d6e8b5c31233d4548c90344f09c5b17178a5b1d Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Lo=C3=AFc=20Lecrenier?= <loic.lecrenier@me.com>
Date: Thu, 30 Mar 2023 14:48:12 +0200
Subject: [PATCH] Fix phrase search bug when the phrase has only one word

---
 milli/src/search/new/resolve_query_graph.rs | 21 +++++++++++++++++----
 1 file changed, 17 insertions(+), 4 deletions(-)

diff --git a/milli/src/search/new/resolve_query_graph.rs b/milli/src/search/new/resolve_query_graph.rs
index 707082cab..ef7adad14 100644
--- a/milli/src/search/new/resolve_query_graph.rs
+++ b/milli/src/search/new/resolve_query_graph.rs
@@ -121,14 +121,27 @@ pub fn compute_phrase_docids(
     phrase: Interned<Phrase>,
 ) -> Result<RoaringBitmap> {
     let Phrase { words } = ctx.phrase_interner.get(phrase).clone();
+
+    if words.is_empty() {
+        return Ok(RoaringBitmap::new());
+    }
+    if words.len() == 1 {
+        if let Some(word) = &words[0] {
+            if let Some(word_docids) = ctx.get_db_word_docids(*word)? {
+                return RoaringBitmapCodec::bytes_decode(word_docids)
+                    .ok_or(heed::Error::Decoding.into());
+            } else {
+                return Ok(RoaringBitmap::new());
+            }
+        } else {
+            return Ok(RoaringBitmap::new());
+        }
+    }
+
     let mut candidates = RoaringBitmap::new();
     let mut first_iter = true;
     let winsize = words.len().min(3);
 
-    if words.is_empty() {
-        return Ok(candidates);
-    }
-
     for win in words.windows(winsize) {
         // Get all the documents with the matching distance for each word pairs.
         let mut bitmaps = Vec::with_capacity(winsize.pow(2));