From 4364bdd63ef58b2094dc252018d3c027302af4f4 Mon Sep 17 00:00:00 2001
From: Julie Tibshirani <julietibs@apache.org>
Date: Wed, 23 Feb 2022 08:22:59 -0800
Subject: [PATCH] LUCENE-10054: Make sure to use Lucene90 codec in unit tests
 (#699)

Before we were using the default Lucene91 codec, so we weren't exercising the
old format.
---
 .../lucene90/Lucene90Codec.java               |  2 +-
 .../lucene90/Lucene90RWCodec.java             | 44 +++++++++++++++++++
 .../TestLucene90HnswVectorsFormat.java        |  3 +-
 3 files changed, 46 insertions(+), 3 deletions(-)
 create mode 100644 lucene/backward-codecs/src/test/org/apache/lucene/backward_codecs/lucene90/Lucene90RWCodec.java

diff --git a/lucene/backward-codecs/src/java/org/apache/lucene/backward_codecs/lucene90/Lucene90Codec.java b/lucene/backward-codecs/src/java/org/apache/lucene/backward_codecs/lucene90/Lucene90Codec.java
index 40ba06606bd..f10e35cf9ce 100644
--- a/lucene/backward-codecs/src/java/org/apache/lucene/backward_codecs/lucene90/Lucene90Codec.java
+++ b/lucene/backward-codecs/src/java/org/apache/lucene/backward_codecs/lucene90/Lucene90Codec.java
@@ -164,7 +164,7 @@ public class Lucene90Codec extends Codec {
   }
 
   @Override
-  public final KnnVectorsFormat knnVectorsFormat() {
+  public KnnVectorsFormat knnVectorsFormat() {
     return knnVectorsFormat;
   }
 
diff --git a/lucene/backward-codecs/src/test/org/apache/lucene/backward_codecs/lucene90/Lucene90RWCodec.java b/lucene/backward-codecs/src/test/org/apache/lucene/backward_codecs/lucene90/Lucene90RWCodec.java
new file mode 100644
index 00000000000..b7c30361d2e
--- /dev/null
+++ b/lucene/backward-codecs/src/test/org/apache/lucene/backward_codecs/lucene90/Lucene90RWCodec.java
@@ -0,0 +1,44 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one or more
+ * contributor license agreements.  See the NOTICE file distributed with
+ * this work for additional information regarding copyright ownership.
+ * The ASF licenses this file to You under the Apache License, Version 2.0
+ * (the "License"); you may not use this file except in compliance with
+ * the License.  You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package org.apache.lucene.backward_codecs.lucene90;
+
+import org.apache.lucene.codecs.KnnVectorsFormat;
+import org.apache.lucene.codecs.perfield.PerFieldKnnVectorsFormat;
+
+public class Lucene90RWCodec extends Lucene90Codec {
+
+  private final KnnVectorsFormat defaultKnnVectorsFormat;
+  private final KnnVectorsFormat knnVectorsFormat =
+      new PerFieldKnnVectorsFormat() {
+        @Override
+        public KnnVectorsFormat getKnnVectorsFormatForField(String field) {
+          return defaultKnnVectorsFormat;
+        }
+      };
+
+  public Lucene90RWCodec() {
+    this.defaultKnnVectorsFormat =
+        new Lucene90RWHnswVectorsFormat(
+            Lucene90HnswVectorsFormat.DEFAULT_MAX_CONN,
+            Lucene90HnswVectorsFormat.DEFAULT_BEAM_WIDTH);
+  }
+
+  @Override
+  public KnnVectorsFormat knnVectorsFormat() {
+    return knnVectorsFormat;
+  }
+}
diff --git a/lucene/backward-codecs/src/test/org/apache/lucene/backward_codecs/lucene90/TestLucene90HnswVectorsFormat.java b/lucene/backward-codecs/src/test/org/apache/lucene/backward_codecs/lucene90/TestLucene90HnswVectorsFormat.java
index 8fe6dc24624..49ebbde7595 100644
--- a/lucene/backward-codecs/src/test/org/apache/lucene/backward_codecs/lucene90/TestLucene90HnswVectorsFormat.java
+++ b/lucene/backward-codecs/src/test/org/apache/lucene/backward_codecs/lucene90/TestLucene90HnswVectorsFormat.java
@@ -23,12 +23,11 @@ import static org.apache.lucene.backward_codecs.lucene90.Lucene90HnswVectorsForm
 import org.apache.lucene.codecs.Codec;
 import org.apache.lucene.codecs.KnnVectorsFormat;
 import org.apache.lucene.tests.index.BaseKnnVectorsFormatTestCase;
-import org.apache.lucene.tests.util.TestUtil;
 
 public class TestLucene90HnswVectorsFormat extends BaseKnnVectorsFormatTestCase {
   @Override
   protected Codec getCodec() {
-    return TestUtil.getDefaultCodec();
+    return new Lucene90RWCodec();
   }
 
   public void testToString() {