LUCENE-9322: Move old field infos format to backwards-codecs. (#2245)

We introduced a new `Lucene90FieldInfosFormat`, so the old
`Lucene60FieldInfosFormat` should live in backwards-codecs.

lucene/backward-codecs/src/java/org/apache/lucene/backward_codecs/lucene60/Lucene60FieldInfosFormat.java

@@ -14,7 +14,7 @@
  * See the License for the specific language governing permissions and
  * limitations under the License.
  */
-package org.apache.lucene.codecs.lucene60;
+package org.apache.lucene.backward_codecs.lucene60;
 
 import java.io.IOException;
 import java.util.Collections;
@@ -311,6 +311,11 @@ public final class Lucene60FieldInfosFormat extends FieldInfosFormat {
     }
   }
 
+  /**
+   * Note: although this format is only used on older versions, we need to keep the write logic in
+   * addition to the read logic. It's possible for field infos on older segments to be written to,
+   * for example as part of in-place doc values updates.
+   */
   @Override
   public void write(
       Directory directory,

lucene/backward-codecs/src/java/org/apache/lucene/backward_codecs/lucene70/Lucene70Codec.java

@@ -18,6 +18,7 @@ package org.apache.lucene.backward_codecs.lucene70;
 
 import org.apache.lucene.backward_codecs.lucene50.Lucene50StoredFieldsFormat;
 import org.apache.lucene.backward_codecs.lucene50.Lucene50StoredFieldsFormat.Mode;
+import org.apache.lucene.backward_codecs.lucene60.Lucene60FieldInfosFormat;
 import org.apache.lucene.backward_codecs.lucene60.Lucene60PointsFormat;
 import org.apache.lucene.codecs.Codec;
 import org.apache.lucene.codecs.CompoundFormat;
@@ -35,7 +36,6 @@ import org.apache.lucene.codecs.VectorFormat;
 import org.apache.lucene.codecs.lucene50.Lucene50CompoundFormat;
 import org.apache.lucene.codecs.lucene50.Lucene50LiveDocsFormat;
 import org.apache.lucene.codecs.lucene50.Lucene50TermVectorsFormat;
-import org.apache.lucene.codecs.lucene60.Lucene60FieldInfosFormat;
 import org.apache.lucene.codecs.perfield.PerFieldDocValuesFormat;
 import org.apache.lucene.codecs.perfield.PerFieldPostingsFormat;
 

lucene/backward-codecs/src/java/org/apache/lucene/backward_codecs/lucene80/Lucene80Codec.java

@@ -17,6 +17,7 @@
 package org.apache.lucene.backward_codecs.lucene80;
 
 import org.apache.lucene.backward_codecs.lucene50.Lucene50StoredFieldsFormat;
+import org.apache.lucene.backward_codecs.lucene60.Lucene60FieldInfosFormat;
 import org.apache.lucene.backward_codecs.lucene60.Lucene60PointsFormat;
 import org.apache.lucene.backward_codecs.lucene70.Lucene70SegmentInfoFormat;
 import org.apache.lucene.codecs.Codec;
@@ -34,7 +35,6 @@ import org.apache.lucene.codecs.VectorFormat;
 import org.apache.lucene.codecs.lucene50.Lucene50CompoundFormat;
 import org.apache.lucene.codecs.lucene50.Lucene50LiveDocsFormat;
 import org.apache.lucene.codecs.lucene50.Lucene50TermVectorsFormat;
-import org.apache.lucene.codecs.lucene60.Lucene60FieldInfosFormat;
 import org.apache.lucene.codecs.lucene80.Lucene80NormsFormat;
 import org.apache.lucene.codecs.perfield.PerFieldDocValuesFormat;
 import org.apache.lucene.codecs.perfield.PerFieldPostingsFormat;

lucene/backward-codecs/src/java/org/apache/lucene/backward_codecs/lucene84/Lucene84Codec.java

@@ -19,6 +19,7 @@ package org.apache.lucene.backward_codecs.lucene84;
 import java.util.Objects;
 import org.apache.lucene.backward_codecs.lucene50.Lucene50StoredFieldsFormat;
 import org.apache.lucene.backward_codecs.lucene50.Lucene50StoredFieldsFormat.Mode;
+import org.apache.lucene.backward_codecs.lucene60.Lucene60FieldInfosFormat;
 import org.apache.lucene.backward_codecs.lucene60.Lucene60PointsFormat;
 import org.apache.lucene.backward_codecs.lucene70.Lucene70SegmentInfoFormat;
 import org.apache.lucene.codecs.Codec;
@@ -37,7 +38,6 @@ import org.apache.lucene.codecs.VectorFormat;
 import org.apache.lucene.codecs.lucene50.Lucene50CompoundFormat;
 import org.apache.lucene.codecs.lucene50.Lucene50LiveDocsFormat;
 import org.apache.lucene.codecs.lucene50.Lucene50TermVectorsFormat;
-import org.apache.lucene.codecs.lucene60.Lucene60FieldInfosFormat;
 import org.apache.lucene.codecs.lucene80.Lucene80NormsFormat;
 import org.apache.lucene.codecs.lucene84.Lucene84PostingsFormat;
 import org.apache.lucene.codecs.perfield.PerFieldDocValuesFormat;

lucene/backward-codecs/src/java/org/apache/lucene/backward_codecs/lucene86/Lucene86Codec.java

@@ -19,6 +19,7 @@ package org.apache.lucene.backward_codecs.lucene86;
 
 import java.util.Objects;
 import org.apache.lucene.backward_codecs.lucene50.Lucene50StoredFieldsFormat;
+import org.apache.lucene.backward_codecs.lucene60.Lucene60FieldInfosFormat;
 import org.apache.lucene.codecs.Codec;
 import org.apache.lucene.codecs.CompoundFormat;
 import org.apache.lucene.codecs.DocValuesFormat;
@@ -35,7 +36,6 @@ import org.apache.lucene.codecs.VectorFormat;
 import org.apache.lucene.codecs.lucene50.Lucene50CompoundFormat;
 import org.apache.lucene.codecs.lucene50.Lucene50LiveDocsFormat;
 import org.apache.lucene.codecs.lucene50.Lucene50TermVectorsFormat;
-import org.apache.lucene.codecs.lucene60.Lucene60FieldInfosFormat;
 import org.apache.lucene.codecs.lucene80.Lucene80NormsFormat;
 import org.apache.lucene.codecs.lucene84.Lucene84PostingsFormat;
 import org.apache.lucene.codecs.lucene86.Lucene86PointsFormat;

lucene/backward-codecs/src/java/org/apache/lucene/backward_codecs/lucene87/Lucene87Codec.java

@@ -18,6 +18,7 @@
 package org.apache.lucene.backward_codecs.lucene87;
 
 import java.util.Objects;
+import org.apache.lucene.backward_codecs.lucene60.Lucene60FieldInfosFormat;
 import org.apache.lucene.codecs.Codec;
 import org.apache.lucene.codecs.CompoundFormat;
 import org.apache.lucene.codecs.DocValuesFormat;
@@ -34,7 +35,6 @@ import org.apache.lucene.codecs.VectorFormat;
 import org.apache.lucene.codecs.lucene50.Lucene50CompoundFormat;
 import org.apache.lucene.codecs.lucene50.Lucene50LiveDocsFormat;
 import org.apache.lucene.codecs.lucene50.Lucene50TermVectorsFormat;
-import org.apache.lucene.codecs.lucene60.Lucene60FieldInfosFormat;
 import org.apache.lucene.codecs.lucene80.Lucene80DocValuesFormat;
 import org.apache.lucene.codecs.lucene80.Lucene80NormsFormat;
 import org.apache.lucene.codecs.lucene84.Lucene84PostingsFormat;

lucene/backward-codecs/src/test/org/apache/lucene/backward_codecs/lucene60/TestLucene60FieldInfosFormat.java

@@ -14,17 +14,15 @@
  * See the License for the specific language governing permissions and
  * limitations under the License.
  */
-package org.apache.lucene.codecs.lucene50;
+package org.apache.lucene.backward_codecs.lucene60;
 
+import org.apache.lucene.backward_codecs.lucene84.Lucene84RWCodec;
 import org.apache.lucene.codecs.Codec;
 import org.apache.lucene.index.BaseFieldInfoFormatTestCase;
-import org.apache.lucene.util.TestUtil;
-
-/** Tests Lucene60FieldInfoFormat */
-public class TestLucene60FieldInfoFormat extends BaseFieldInfoFormatTestCase {
 
+public class TestLucene60FieldInfosFormat extends BaseFieldInfoFormatTestCase {
   @Override
   protected Codec getCodec() {
-    return TestUtil.getDefaultCodec();
+    return new Lucene84RWCodec();
   }
 }

lucene/core/src/java/org/apache/lucene/codecs/lucene60/package-info.java

@@ -1,22 +0,0 @@
-/*
- * 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.
- */
-
-/**
- * Components from the Lucene 6.0 index format. See {@link org.apache.lucene.codecs.lucene90} for an
- * overview of the current index format.
- */
-package org.apache.lucene.codecs.lucene60;

lucene/core/src/java/org/apache/lucene/codecs/lucene90/package-info.java

@@ -240,7 +240,7 @@
  * systems that frequently run out of file handles.</td>
  * </tr>
  * <tr>
- * <td>{@link org.apache.lucene.codecs.lucene60.Lucene60FieldInfosFormat Fields}</td>
+ * <td>{@link org.apache.lucene.codecs.lucene90.Lucene90FieldInfosFormat Fields}</td>
  * <td>.fnm</td>
  * <td>Stores information about the fields</td>
  * </tr>

lucene/facet/build.gradle

@@ -28,5 +28,5 @@ dependencies {
   testImplementation project(':lucene:test-framework')
   testImplementation project(':lucene:queries')
   // Required for opening older indexes for backward compatibility tests
-  testCompile group: 'org.apache.lucene', name: 'lucene-codecs', version: '8.6.3'
+  testImplementation project(':lucene:backward-codecs')
 }

versions.lock

@@ -204,8 +204,6 @@ org.apache.kerby:kerb-server:1.0.1 (1 constraints: 0405f135)
 org.apache.kerby:kerb-simplekdc:1.0.1 (1 constraints: 0405f135)
 org.apache.kerby:kerby-kdc:1.0.1 (1 constraints: 0405f135)
 org.apache.logging.log4j:log4j-1.2-api:2.13.2 (1 constraints: 3a053a3b)
-org.apache.lucene:lucene-codecs:8.6.3 (1 constraints: 13052836)
-org.apache.lucene:lucene-core:8.6.3 (1 constraints: 7f0d022f)
 org.asciidoctor:asciidoctorj:1.6.2 (1 constraints: 0b050436)
 org.asciidoctor:asciidoctorj-api:1.6.2 (1 constraints: e30cfb0d)
 org.hsqldb:hsqldb:2.4.0 (1 constraints: 08050136)