From 4be11f961b624dcd027d7c799dbd5a48c46fd083 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Cl=C3=A9ment=20Renault?= <renault.cle@gmail.com>
Date: Fri, 20 Dec 2019 17:39:32 +0100
Subject: [PATCH] Use an ugly trick to avoid cloning the FST

---
 meilisearch-core/src/bucket_sort.rs |  2 +-
 meilisearch-core/src/store/main.rs  | 11 +++++++++++
 2 files changed, 12 insertions(+), 1 deletion(-)

diff --git a/meilisearch-core/src/bucket_sort.rs b/meilisearch-core/src/bucket_sort.rs
index a0609d30d..f173c2955 100644
--- a/meilisearch-core/src/bucket_sort.rs
+++ b/meilisearch-core/src/bucket_sort.rs
@@ -446,7 +446,7 @@ fn fetch_matches<'txn, 'tag>(
 ) -> MResult<Vec<BareMatch<'tag>>>
 {
     let before_words_fst = Instant::now();
-    let words = match main_store.words_fst(reader)? {
+    let words = match unsafe { main_store.static_words_fst(reader)? } {
         Some(words) => words,
         None => return Ok(Vec::new()),
     };
diff --git a/meilisearch-core/src/store/main.rs b/meilisearch-core/src/store/main.rs
index 0efdd140e..90c662db4 100644
--- a/meilisearch-core/src/store/main.rs
+++ b/meilisearch-core/src/store/main.rs
@@ -67,6 +67,17 @@ impl Main {
         self.main.put::<_, Str, ByteSlice>(writer, WORDS_KEY, bytes)
     }
 
+    pub unsafe fn static_words_fst(self, reader: &heed::RoTxn<MainT>) -> ZResult<Option<fst::Set>> {
+        match self.main.get::<_, Str, ByteSlice>(reader, WORDS_KEY)? {
+            Some(bytes) => {
+                let bytes: &'static [u8] = std::mem::transmute(bytes);
+                let set = fst::Set::from_static_slice(bytes).unwrap();
+                Ok(Some(set))
+            }
+            None => Ok(None),
+        }
+    }
+
     pub fn words_fst(self, reader: &heed::RoTxn<MainT>) -> ZResult<Option<fst::Set>> {
         match self.main.get::<_, Str, ByteSlice>(reader, WORDS_KEY)? {
             Some(bytes) => {