Address PR comments

Author: guilload

quickwit/quickwit-search/src/list_fields/cache.rs

@@ -38,3 +38,24 @@ impl ListFieldsCache {
         self.cache.put(split_id, serialized_split_fields);
     }
 }
+
+#[cfg(test)]
+mod tests {
+    use bytesize::ByteSize;
+
+    use super::*;
+
+    #[test]
+    fn list_fields_cache_get_miss_returns_none() {
+        let cache = ListFieldsCache::new(&CacheConfig::default_with_capacity(ByteSize::mb(1)));
+        assert!(cache.get(&"missing".to_string()).is_none());
+    }
+
+    #[test]
+    fn list_fields_cache_put_then_get_roundtrips() {
+        let cache = ListFieldsCache::new(&CacheConfig::default_with_capacity(ByteSize::mb(1)));
+        let payload = OwnedBytes::new(b"hello".to_vec());
+        cache.put("split-1".to_string(), payload.clone());
+        assert_eq!(cache.get(&"split-1".to_string()), Some(payload));
+    }
+}

quickwit/quickwit-search/src/list_fields/root.rs

@@ -204,5 +204,5 @@ async fn merge_fields_metadata(
             })
         })
         .await
-        .context("failed to merge single split list fields")?
+        .context("failed to merge leaf list fields responses")?
 }