LUCENE-10168: Only test N-2 codecs on nightly runs. (#466)

In order for tests to keep running fast, this annotates all tests of N-2 codecs
with `@Nightly`. To keep good coverage of releases, the smoke tester is now
configured to run nightly tests.

dev-tools/scripts/smokeTestRelease.py

@@ -1129,6 +1129,12 @@ def smokeTest(java, baseURL, gitRevision, version, tmpDir, isSigned, local_keys,
   # disable flakey tests for smoke-tester runs:
   testArgs = '-Dtests.badapples=false %s' % testArgs
 
+  # Tests annotated @Nightly are more resource-intensive but often cover
+  # important code paths. They're disabled by default to preserve a good
+  # developer experience, but we enable them for smoke tests where we want good
+  # coverage.
+  testArgs = '-Dtests.nigthly=true %s' % testArgs
+
   if FORCE_CLEAN:
     if os.path.exists(tmpDir):
       raise RuntimeError('temp dir %s exists; please remove first' % tmpDir)

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

@@ -1,326 +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.
- */
-package org.apache.lucene.backward_codecs.lucene70;
-
-import java.io.DataInput;
-import java.io.IOException;
-import org.apache.lucene.search.DocIdSetIterator;
-import org.apache.lucene.store.IndexInput;
-import org.apache.lucene.store.IndexOutput;
-import org.apache.lucene.util.BitSetIterator;
-import org.apache.lucene.util.FixedBitSet;
-import org.apache.lucene.util.RoaringDocIdSet;
-
-/**
- * Disk-based implementation of a {@link DocIdSetIterator} which can return the index of the current
- * document, i.e. the ordinal of the current document among the list of documents that this iterator
- * can return. This is useful to implement sparse doc values by only having to encode values for
- * documents that actually have a value.
- *
- * <p>Implementation-wise, this {@link DocIdSetIterator} is inspired of {@link RoaringDocIdSet
- * roaring bitmaps} and encodes ranges of {@code 65536} documents independently and picks between 3
- * encodings depending on the density of the range:
- *
- * <ul>
- *   <li>{@code ALL} if the range contains 65536 documents exactly,
- *   <li>{@code DENSE} if the range contains 4096 documents or more; in that case documents are
- *       stored in a bit set,
- *   <li>{@code SPARSE} otherwise, and the lower 16 bits of the doc IDs are stored in a {@link
- *       DataInput#readShort() short}.
- * </ul>
- *
- * <p>Only ranges that contain at least one value are encoded.
- *
- * <p>This implementation uses 6 bytes per document in the worst-case, which happens in the case
- * that all ranges contain exactly one document.
- *
- * @lucene.internal
- */
-final class IndexedDISI extends DocIdSetIterator {
-
-  static final int MAX_ARRAY_LENGTH = (1 << 12) - 1;
-
-  private static void flush(int block, FixedBitSet buffer, int cardinality, IndexOutput out)
-      throws IOException {
-    assert block >= 0 && block < 65536;
-    out.writeShort((short) block);
-    assert cardinality > 0 && cardinality <= 65536;
-    out.writeShort((short) (cardinality - 1));
-    if (cardinality > MAX_ARRAY_LENGTH) {
-      if (cardinality != 65536) { // all docs are set
-        for (long word : buffer.getBits()) {
-          out.writeLong(word);
-        }
-      }
-    } else {
-      BitSetIterator it = new BitSetIterator(buffer, cardinality);
-      for (int doc = it.nextDoc(); doc != DocIdSetIterator.NO_MORE_DOCS; doc = it.nextDoc()) {
-        out.writeShort((short) doc);
-      }
-    }
-  }
-
-  static void writeBitSet(DocIdSetIterator it, IndexOutput out) throws IOException {
-    int i = 0;
-    final FixedBitSet buffer = new FixedBitSet(1 << 16);
-    int prevBlock = -1;
-    for (int doc = it.nextDoc(); doc != DocIdSetIterator.NO_MORE_DOCS; doc = it.nextDoc()) {
-      final int block = doc >>> 16;
-      if (prevBlock != -1 && block != prevBlock) {
-        flush(prevBlock, buffer, i, out);
-        buffer.clear(0, buffer.length());
-        prevBlock = block;
-        i = 0;
-      }
-      buffer.set(doc & 0xFFFF);
-      i++;
-      prevBlock = block;
-    }
-    if (i > 0) {
-      flush(prevBlock, buffer, i, out);
-      buffer.clear(0, buffer.length());
-    }
-    // NO_MORE_DOCS is stored explicitly
-    buffer.set(DocIdSetIterator.NO_MORE_DOCS & 0xFFFF);
-    flush(DocIdSetIterator.NO_MORE_DOCS >>> 16, buffer, 1, out);
-  }
-
-  /** The slice that stores the {@link DocIdSetIterator}. */
-  private final IndexInput slice;
-
-  private final long cost;
-
-  IndexedDISI(IndexInput in, long offset, long length, long cost) throws IOException {
-    this(in.slice("docs", offset, length), cost);
-  }
-
-  // This constructor allows to pass the slice directly in case it helps reuse
-  // see eg. Lucene70 norms producer's merge instance
-  IndexedDISI(IndexInput slice, long cost) throws IOException {
-    this.slice = slice;
-    this.cost = cost;
-  }
-
-  private int block = -1;
-  private long blockEnd;
-  private int nextBlockIndex = -1;
-  Method method;
-
-  private int doc = -1;
-  private int index = -1;
-
-  // SPARSE variables
-  boolean exists;
-
-  // DENSE variables
-  private long word;
-  private int wordIndex = -1;
-  // number of one bits encountered so far, including those of `word`
-  private int numberOfOnes;
-
-  // ALL variables
-  private int gap;
-
-  @Override
-  public int docID() {
-    return doc;
-  }
-
-  @Override
-  public int advance(int target) throws IOException {
-    final int targetBlock = target & 0xFFFF0000;
-    if (block < targetBlock) {
-      advanceBlock(targetBlock);
-    }
-    if (block == targetBlock) {
-      if (method.advanceWithinBlock(this, target)) {
-        return doc;
-      }
-      readBlockHeader();
-    }
-    boolean found = method.advanceWithinBlock(this, block);
-    assert found;
-    return doc;
-  }
-
-  public boolean advanceExact(int target) throws IOException {
-    final int targetBlock = target & 0xFFFF0000;
-    if (block < targetBlock) {
-      advanceBlock(targetBlock);
-    }
-    boolean found = block == targetBlock && method.advanceExactWithinBlock(this, target);
-    this.doc = target;
-    return found;
-  }
-
-  private void advanceBlock(int targetBlock) throws IOException {
-    do {
-      slice.seek(blockEnd);
-      readBlockHeader();
-    } while (block < targetBlock);
-  }
-
-  private void readBlockHeader() throws IOException {
-    block = Short.toUnsignedInt(slice.readShort()) << 16;
-    assert block >= 0;
-    final int numValues = 1 + Short.toUnsignedInt(slice.readShort());
-    index = nextBlockIndex;
-    nextBlockIndex = index + numValues;
-    if (numValues <= MAX_ARRAY_LENGTH) {
-      method = Method.SPARSE;
-      blockEnd = slice.getFilePointer() + (numValues << 1);
-    } else if (numValues == 65536) {
-      method = Method.ALL;
-      blockEnd = slice.getFilePointer();
-      gap = block - index - 1;
-    } else {
-      method = Method.DENSE;
-      blockEnd = slice.getFilePointer() + (1 << 13);
-      wordIndex = -1;
-      numberOfOnes = index + 1;
-    }
-  }
-
-  @Override
-  public int nextDoc() throws IOException {
-    return advance(doc + 1);
-  }
-
-  public int index() {
-    return index;
-  }
-
-  @Override
-  public long cost() {
-    return cost;
-  }
-
-  enum Method {
-    SPARSE {
-      @Override
-      boolean advanceWithinBlock(IndexedDISI disi, int target) throws IOException {
-        final int targetInBlock = target & 0xFFFF;
-        // TODO: binary search
-        for (; disi.index < disi.nextBlockIndex; ) {
-          int doc = Short.toUnsignedInt(disi.slice.readShort());
-          disi.index++;
-          if (doc >= targetInBlock) {
-            disi.doc = disi.block | doc;
-            disi.exists = true;
-            return true;
-          }
-        }
-        return false;
-      }
-
-      @Override
-      boolean advanceExactWithinBlock(IndexedDISI disi, int target) throws IOException {
-        final int targetInBlock = target & 0xFFFF;
-        // TODO: binary search
-        if (target == disi.doc) {
-          return disi.exists;
-        }
-        for (; disi.index < disi.nextBlockIndex; ) {
-          int doc = Short.toUnsignedInt(disi.slice.readShort());
-          disi.index++;
-          if (doc >= targetInBlock) {
-            if (doc != targetInBlock) {
-              disi.index--;
-              disi.slice.seek(disi.slice.getFilePointer() - Short.BYTES);
-              break;
-            }
-            disi.exists = true;
-            return true;
-          }
-        }
-        disi.exists = false;
-        return false;
-      }
-    },
-    DENSE {
-      @Override
-      boolean advanceWithinBlock(IndexedDISI disi, int target) throws IOException {
-        final int targetInBlock = target & 0xFFFF;
-        final int targetWordIndex = targetInBlock >>> 6;
-        for (int i = disi.wordIndex + 1; i <= targetWordIndex; ++i) {
-          disi.word = disi.slice.readLong();
-          disi.numberOfOnes += Long.bitCount(disi.word);
-        }
-        disi.wordIndex = targetWordIndex;
-
-        long leftBits = disi.word >>> target;
-        if (leftBits != 0L) {
-          disi.doc = target + Long.numberOfTrailingZeros(leftBits);
-          disi.index = disi.numberOfOnes - Long.bitCount(leftBits);
-          return true;
-        }
-
-        while (++disi.wordIndex < 1024) {
-          disi.word = disi.slice.readLong();
-          if (disi.word != 0) {
-            disi.index = disi.numberOfOnes;
-            disi.numberOfOnes += Long.bitCount(disi.word);
-            disi.doc = disi.block | (disi.wordIndex << 6) | Long.numberOfTrailingZeros(disi.word);
-            return true;
-          }
-        }
-        return false;
-      }
-
-      @Override
-      boolean advanceExactWithinBlock(IndexedDISI disi, int target) throws IOException {
-        final int targetInBlock = target & 0xFFFF;
-        final int targetWordIndex = targetInBlock >>> 6;
-        for (int i = disi.wordIndex + 1; i <= targetWordIndex; ++i) {
-          disi.word = disi.slice.readLong();
-          disi.numberOfOnes += Long.bitCount(disi.word);
-        }
-        disi.wordIndex = targetWordIndex;
-
-        long leftBits = disi.word >>> target;
-        disi.index = disi.numberOfOnes - Long.bitCount(leftBits);
-        return (leftBits & 1L) != 0;
-      }
-    },
-    ALL {
-      @Override
-      boolean advanceWithinBlock(IndexedDISI disi, int target) throws IOException {
-        disi.doc = target;
-        disi.index = target - disi.gap;
-        return true;
-      }
-
-      @Override
-      boolean advanceExactWithinBlock(IndexedDISI disi, int target) throws IOException {
-        disi.index = target - disi.gap;
-        return true;
-      }
-    };
-
-    /**
-     * Advance to the first doc from the block that is equal to or greater than {@code target}.
-     * Return true if there is such a doc and false otherwise.
-     */
-    abstract boolean advanceWithinBlock(IndexedDISI disi, int target) throws IOException;
-
-    /**
-     * Advance the iterator exactly to the position corresponding to the given {@code target} and
-     * return whether this document exists.
-     */
-    abstract boolean advanceExactWithinBlock(IndexedDISI disi, int target) throws IOException;
-  }
-}

lucene/backward-codecs/src/test/org/apache/lucene/backward_codecs/lucene50/TestBlockPostingsFormat.java

@@ -39,9 +39,11 @@ import org.apache.lucene.store.Directory;
 import org.apache.lucene.store.IOContext;
 import org.apache.lucene.store.IndexInput;
 import org.apache.lucene.store.IndexOutput;
+import org.apache.lucene.util.LuceneTestCase.Nightly;
 import org.apache.lucene.util.TestUtil;
 
 /** Tests BlockPostingsFormat */
+@Nightly // N-2 formats are only tested on nightly runs
 public class TestBlockPostingsFormat extends BasePostingsFormatTestCase {
   private final Codec codec = TestUtil.alwaysPostingsFormat(new Lucene50RWPostingsFormat());
 

lucene/backward-codecs/src/test/org/apache/lucene/backward_codecs/lucene50/TestBlockPostingsFormat2.java

@@ -29,9 +29,11 @@ import org.apache.lucene.index.IndexableField;
 import org.apache.lucene.index.RandomIndexWriter;
 import org.apache.lucene.store.Directory;
 import org.apache.lucene.util.LuceneTestCase;
+import org.apache.lucene.util.LuceneTestCase.Nightly;
 import org.apache.lucene.util.TestUtil;
 
 /** Tests special cases of BlockPostingsFormat */
+@Nightly // N-2 formats are only tested on nightly runs
 public class TestBlockPostingsFormat2 extends LuceneTestCase {
   Directory dir;
   RandomIndexWriter iw;

lucene/backward-codecs/src/test/org/apache/lucene/backward_codecs/lucene50/TestBlockPostingsFormat3.java

@@ -47,12 +47,14 @@ import org.apache.lucene.store.Directory;
 import org.apache.lucene.util.BytesRef;
 import org.apache.lucene.util.English;
 import org.apache.lucene.util.LuceneTestCase;
+import org.apache.lucene.util.LuceneTestCase.Nightly;
 import org.apache.lucene.util.TestUtil;
 import org.apache.lucene.util.automaton.AutomatonTestUtil;
 import org.apache.lucene.util.automaton.CompiledAutomaton;
 import org.apache.lucene.util.automaton.RegExp;
 
 /** Tests partial enumeration (only pulling a subset of the indexed data) */
+@Nightly // N-2 formats are only tested on nightly runs
 public class TestBlockPostingsFormat3 extends LuceneTestCase {
   private final int MAXDOC =
       TEST_NIGHTLY ? Lucene50PostingsFormat.BLOCK_SIZE * 20 : Lucene50PostingsFormat.BLOCK_SIZE * 3;

lucene/backward-codecs/src/test/org/apache/lucene/backward_codecs/lucene50/TestForUtil.java

@@ -30,8 +30,10 @@ import org.apache.lucene.store.IndexInput;
 import org.apache.lucene.store.IndexOutput;
 import org.apache.lucene.util.ArrayUtil;
 import org.apache.lucene.util.LuceneTestCase;
+import org.apache.lucene.util.LuceneTestCase.Nightly;
 import org.apache.lucene.util.packed.PackedInts;
 
+@Nightly // N-2 formats are only tested on nightly runs
 public class TestForUtil extends LuceneTestCase {
 
   public void testEncodeDecode() throws IOException {

lucene/backward-codecs/src/test/org/apache/lucene/backward_codecs/lucene50/TestLucene50CompoundFormat.java

@@ -19,9 +19,10 @@ package org.apache.lucene.backward_codecs.lucene50;
 import org.apache.lucene.backward_codecs.lucene87.Lucene87RWCodec;
 import org.apache.lucene.codecs.Codec;
 import org.apache.lucene.index.BaseCompoundFormatTestCase;
+import org.apache.lucene.util.LuceneTestCase.Nightly;
 
+@Nightly // N-2 formats are only tested on nightly runs
 public class TestLucene50CompoundFormat extends BaseCompoundFormatTestCase {
-  ;
 
   @Override
   protected Codec getCodec() {

lucene/backward-codecs/src/test/org/apache/lucene/backward_codecs/lucene50/TestLucene50LiveDocsFormat.java

@@ -19,7 +19,9 @@ package org.apache.lucene.backward_codecs.lucene50;
 import org.apache.lucene.backward_codecs.lucene86.Lucene86RWCodec;
 import org.apache.lucene.codecs.Codec;
 import org.apache.lucene.index.BaseLiveDocsFormatTestCase;
+import org.apache.lucene.util.LuceneTestCase.Nightly;
 
+@Nightly // N-2 formats are only tested on nightly runs
 public class TestLucene50LiveDocsFormat extends BaseLiveDocsFormatTestCase {
 
   @Override

lucene/backward-codecs/src/test/org/apache/lucene/backward_codecs/lucene50/TestLucene50StoredFieldsFormat.java

@@ -19,7 +19,9 @@ package org.apache.lucene.backward_codecs.lucene50;
 import org.apache.lucene.backward_codecs.lucene86.Lucene86RWCodec;
 import org.apache.lucene.codecs.Codec;
 import org.apache.lucene.index.BaseStoredFieldsFormatTestCase;
+import org.apache.lucene.util.LuceneTestCase.Nightly;
 
+@Nightly // N-2 formats are only tested on nightly runs
 public class TestLucene50StoredFieldsFormat extends BaseStoredFieldsFormatTestCase {
   @Override
   protected Codec getCodec() {

lucene/backward-codecs/src/test/org/apache/lucene/backward_codecs/lucene50/TestLucene50StoredFieldsFormatHighCompression.java

@@ -27,7 +27,9 @@ import org.apache.lucene.index.DirectoryReader;
 import org.apache.lucene.index.IndexWriter;
 import org.apache.lucene.index.IndexWriterConfig;
 import org.apache.lucene.store.Directory;
+import org.apache.lucene.util.LuceneTestCase.Nightly;
 
+@Nightly // N-2 formats are only tested on nightly runs
 public class TestLucene50StoredFieldsFormatHighCompression extends BaseStoredFieldsFormatTestCase {
   @Override
   protected Codec getCodec() {

lucene/backward-codecs/src/test/org/apache/lucene/backward_codecs/lucene50/TestLucene50StoredFieldsFormatMergeInstance.java

@@ -16,7 +16,10 @@
  */
 package org.apache.lucene.backward_codecs.lucene50;
 
+import org.apache.lucene.util.LuceneTestCase.Nightly;
+
 /** Test the merge instance of the Lucene50 stored fields format. */
+@Nightly // N-2 formats are only tested on nightly runs
 public class TestLucene50StoredFieldsFormatMergeInstance extends TestLucene50StoredFieldsFormat {
 
   @Override

lucene/backward-codecs/src/test/org/apache/lucene/backward_codecs/lucene50/TestLucene50TermVectorsFormat.java

@@ -19,7 +19,9 @@ package org.apache.lucene.backward_codecs.lucene50;
 import org.apache.lucene.backward_codecs.lucene87.Lucene87RWCodec;
 import org.apache.lucene.codecs.Codec;
 import org.apache.lucene.index.BaseTermVectorsFormatTestCase;
+import org.apache.lucene.util.LuceneTestCase.Nightly;
 
+@Nightly // N-2 formats are only tested on nightly runs
 public class TestLucene50TermVectorsFormat extends BaseTermVectorsFormatTestCase {
 
   @Override

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

@@ -19,7 +19,9 @@ 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.LuceneTestCase.Nightly;
 
+@Nightly // N-2 formats are only tested on nightly runs
 public class TestLucene60FieldInfosFormat extends BaseFieldInfoFormatTestCase {
   @Override
   protected Codec getCodec() {

lucene/backward-codecs/src/test/org/apache/lucene/backward_codecs/lucene60/TestLucene60PointsFormat.java

@@ -33,10 +33,12 @@ import org.apache.lucene.index.PointValues;
 import org.apache.lucene.index.PointValues.IntersectVisitor;
 import org.apache.lucene.index.PointValues.Relation;
 import org.apache.lucene.store.Directory;
+import org.apache.lucene.util.LuceneTestCase.Nightly;
 import org.apache.lucene.util.TestUtil;
 import org.apache.lucene.util.bkd.BKDConfig;
 
 /** Tests Lucene60PointsFormat */
+@Nightly // N-2 formats are only tested on nightly runs
 public class TestLucene60PointsFormat extends BasePointsFormatTestCase {
   private final Codec codec;
   private final int maxPointsInLeafNode;

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

@@ -1,252 +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.
- */
-package org.apache.lucene.backward_codecs.lucene70;
-
-import java.io.IOException;
-import java.util.ArrayList;
-import java.util.List;
-import org.apache.lucene.backward_codecs.store.EndiannessReverserUtil;
-import org.apache.lucene.search.DocIdSetIterator;
-import org.apache.lucene.store.Directory;
-import org.apache.lucene.store.IOContext;
-import org.apache.lucene.store.IndexInput;
-import org.apache.lucene.store.IndexOutput;
-import org.apache.lucene.util.BitSetIterator;
-import org.apache.lucene.util.FixedBitSet;
-import org.apache.lucene.util.LuceneTestCase;
-import org.apache.lucene.util.TestUtil;
-
-public class TestIndexedDISI extends LuceneTestCase {
-
-  public void testEmpty() throws IOException {
-    int maxDoc = TestUtil.nextInt(random(), 1, 100000);
-    FixedBitSet set = new FixedBitSet(maxDoc);
-    try (Directory dir = newDirectory()) {
-      doTest(set, dir);
-    }
-  }
-
-  public void testOneDoc() throws IOException {
-    int maxDoc = TestUtil.nextInt(random(), 1, 100000);
-    FixedBitSet set = new FixedBitSet(maxDoc);
-    set.set(random().nextInt(maxDoc));
-    try (Directory dir = newDirectory()) {
-      doTest(set, dir);
-    }
-  }
-
-  public void testTwoDocs() throws IOException {
-    int maxDoc = TestUtil.nextInt(random(), 1, 100000);
-    FixedBitSet set = new FixedBitSet(maxDoc);
-    set.set(random().nextInt(maxDoc));
-    set.set(random().nextInt(maxDoc));
-    try (Directory dir = newDirectory()) {
-      doTest(set, dir);
-    }
-  }
-
-  public void testAllDocs() throws IOException {
-    int maxDoc = TestUtil.nextInt(random(), 1, 100000);
-    FixedBitSet set = new FixedBitSet(maxDoc);
-    set.set(1, maxDoc);
-    try (Directory dir = newDirectory()) {
-      doTest(set, dir);
-    }
-  }
-
-  public void testHalfFull() throws IOException {
-    int maxDoc = TestUtil.nextInt(random(), 1, 100000);
-    FixedBitSet set = new FixedBitSet(maxDoc);
-    for (int i = random().nextInt(2); i < maxDoc; i += TestUtil.nextInt(random(), 1, 3)) {
-      set.set(i);
-    }
-    try (Directory dir = newDirectory()) {
-      doTest(set, dir);
-    }
-  }
-
-  public void testDocRange() throws IOException {
-    try (Directory dir = newDirectory()) {
-      for (int iter = 0; iter < 10; ++iter) {
-        int maxDoc = TestUtil.nextInt(random(), 1, 1000000);
-        FixedBitSet set = new FixedBitSet(maxDoc);
-        final int start = random().nextInt(maxDoc);
-        final int end = TestUtil.nextInt(random(), start + 1, maxDoc);
-        set.set(start, end);
-        doTest(set, dir);
-      }
-    }
-  }
-
-  public void testSparseDenseBoundary() throws IOException {
-    try (Directory dir = newDirectory()) {
-      FixedBitSet set = new FixedBitSet(200000);
-      int start = 65536 + random().nextInt(100);
-
-      // we set MAX_ARRAY_LENGTH bits so the encoding will be sparse
-      set.set(start, start + IndexedDISI.MAX_ARRAY_LENGTH);
-      long length;
-      try (IndexOutput out =
-          EndiannessReverserUtil.createOutput(dir, "sparse", IOContext.DEFAULT)) {
-        IndexedDISI.writeBitSet(new BitSetIterator(set, IndexedDISI.MAX_ARRAY_LENGTH), out);
-        length = out.getFilePointer();
-      }
-      try (IndexInput in = EndiannessReverserUtil.openInput(dir, "sparse", IOContext.DEFAULT)) {
-        IndexedDISI disi = new IndexedDISI(in, 0L, length, IndexedDISI.MAX_ARRAY_LENGTH);
-        assertEquals(start, disi.nextDoc());
-        assertEquals(IndexedDISI.Method.SPARSE, disi.method);
-      }
-      doTest(set, dir);
-
-      // now we set one more bit so the encoding will be dense
-      set.set(start + IndexedDISI.MAX_ARRAY_LENGTH + random().nextInt(100));
-      try (IndexOutput out = EndiannessReverserUtil.createOutput(dir, "bar", IOContext.DEFAULT)) {
-        IndexedDISI.writeBitSet(new BitSetIterator(set, IndexedDISI.MAX_ARRAY_LENGTH + 1), out);
-        length = out.getFilePointer();
-      }
-      try (IndexInput in = EndiannessReverserUtil.openInput(dir, "bar", IOContext.DEFAULT)) {
-        IndexedDISI disi = new IndexedDISI(in, 0L, length, IndexedDISI.MAX_ARRAY_LENGTH + 1);
-        assertEquals(start, disi.nextDoc());
-        assertEquals(IndexedDISI.Method.DENSE, disi.method);
-      }
-      doTest(set, dir);
-    }
-  }
-
-  public void testOneDocMissing() throws IOException {
-    int maxDoc = TestUtil.nextInt(random(), 1, 1000000);
-    FixedBitSet set = new FixedBitSet(maxDoc);
-    set.set(0, maxDoc);
-    set.clear(random().nextInt(maxDoc));
-    try (Directory dir = newDirectory()) {
-      doTest(set, dir);
-    }
-  }
-
-  public void testFewMissingDocs() throws IOException {
-    try (Directory dir = newDirectory()) {
-      int numIters = atLeast(10);
-      for (int iter = 0; iter < numIters; ++iter) {
-        int maxDoc = TestUtil.nextInt(random(), 1, 100000);
-        FixedBitSet set = new FixedBitSet(maxDoc);
-        set.set(0, maxDoc);
-        final int numMissingDocs = TestUtil.nextInt(random(), 2, 1000);
-        for (int i = 0; i < numMissingDocs; ++i) {
-          set.clear(random().nextInt(maxDoc));
-        }
-        doTest(set, dir);
-      }
-    }
-  }
-
-  public void testRandom() throws IOException {
-    try (Directory dir = newDirectory()) {
-      int numIters = atLeast(3);
-      for (int i = 0; i < numIters; ++i) {
-        doTestRandom(dir);
-      }
-    }
-  }
-
-  private void doTestRandom(Directory dir) throws IOException {
-    List<Integer> docs = new ArrayList<>();
-    final int maxStep = TestUtil.nextInt(random(), 1, 1 << TestUtil.nextInt(random(), 2, 20));
-    final int numDocs =
-        TestUtil.nextInt(random(), 1, Math.min(100000, Integer.MAX_VALUE / maxStep));
-    for (int doc = -1, i = 0; i < numDocs; ++i) {
-      doc += TestUtil.nextInt(random(), 1, maxStep);
-      docs.add(doc);
-    }
-    final int maxDoc = docs.get(docs.size() - 1) + TestUtil.nextInt(random(), 1, 100);
-
-    FixedBitSet set = new FixedBitSet(maxDoc);
-    for (int doc : docs) {
-      set.set(doc);
-    }
-
-    doTest(set, dir);
-  }
-
-  private void doTest(FixedBitSet set, Directory dir) throws IOException {
-    final int cardinality = set.cardinality();
-    long length;
-    try (IndexOutput out = EndiannessReverserUtil.createOutput(dir, "foo", IOContext.DEFAULT)) {
-      IndexedDISI.writeBitSet(new BitSetIterator(set, cardinality), out);
-      length = out.getFilePointer();
-    }
-
-    try (IndexInput in = EndiannessReverserUtil.openInput(dir, "foo", IOContext.DEFAULT)) {
-      IndexedDISI disi = new IndexedDISI(in, 0L, length, cardinality);
-      BitSetIterator disi2 = new BitSetIterator(set, cardinality);
-      int i = 0;
-      for (int doc = disi2.nextDoc(); doc != DocIdSetIterator.NO_MORE_DOCS; doc = disi2.nextDoc()) {
-        assertEquals(doc, disi.nextDoc());
-        assertEquals(i++, disi.index());
-      }
-      assertEquals(DocIdSetIterator.NO_MORE_DOCS, disi.nextDoc());
-    }
-
-    for (int step : new int[] {1, 10, 100, 1000, 10000, 100000}) {
-      try (IndexInput in = EndiannessReverserUtil.openInput(dir, "foo", IOContext.DEFAULT)) {
-        IndexedDISI disi = new IndexedDISI(in, 0L, length, cardinality);
-        BitSetIterator disi2 = new BitSetIterator(set, cardinality);
-        int index = -1;
-        while (true) {
-          int target = disi2.docID() + step;
-          int doc;
-          do {
-            doc = disi2.nextDoc();
-            index++;
-          } while (doc < target);
-          assertEquals(doc, disi.advance(target));
-          if (doc == DocIdSetIterator.NO_MORE_DOCS) {
-            break;
-          }
-          assertEquals(index, disi.index());
-        }
-      }
-    }
-
-    for (int step : new int[] {10, 100, 1000, 10000, 100000}) {
-      try (IndexInput in = EndiannessReverserUtil.openInput(dir, "foo", IOContext.DEFAULT)) {
-        IndexedDISI disi = new IndexedDISI(in, 0L, length, cardinality);
-        BitSetIterator disi2 = new BitSetIterator(set, cardinality);
-        int index = -1;
-        for (int target = 0; target < set.length(); ) {
-          target += TestUtil.nextInt(random(), 0, step);
-          int doc = disi2.docID();
-          while (doc < target) {
-            doc = disi2.nextDoc();
-            index++;
-          }
-
-          boolean exists = disi.advanceExact(target);
-          assertEquals(doc == target, exists);
-          if (exists) {
-            assertEquals(index, disi.index());
-          } else if (random().nextBoolean()) {
-            assertEquals(doc, disi.nextDoc());
-            assertEquals(index, disi.index());
-            target = doc;
-          }
-        }
-      }
-    }
-
-    dir.deleteFile("foo");
-  }
-}

lucene/backward-codecs/src/test/org/apache/lucene/backward_codecs/lucene70/TestLucene70SegmentInfoFormat.java

@@ -20,8 +20,10 @@ package org.apache.lucene.backward_codecs.lucene70;
 import org.apache.lucene.backward_codecs.lucene84.Lucene84RWCodec;
 import org.apache.lucene.codecs.Codec;
 import org.apache.lucene.index.BaseSegmentInfoFormatTestCase;
+import org.apache.lucene.util.LuceneTestCase.Nightly;
 import org.apache.lucene.util.Version;
 
+@Nightly // N-2 formats are only tested on nightly runs
 public class TestLucene70SegmentInfoFormat extends BaseSegmentInfoFormatTestCase {
 
   @Override

lucene/backward-codecs/src/test/org/apache/lucene/backward_codecs/lucene80/TestBestCompressionLucene80DocValuesFormat.java

@@ -17,9 +17,11 @@
 package org.apache.lucene.backward_codecs.lucene80;
 
 import org.apache.lucene.codecs.Codec;
+import org.apache.lucene.util.LuceneTestCase.Nightly;
 import org.apache.lucene.util.TestUtil;
 
 /** Tests Lucene80DocValuesFormat */
+@Nightly // N-2 formats are only tested on nightly runs
 public class TestBestCompressionLucene80DocValuesFormat
     extends BaseLucene80DocValuesFormatTestCase {
   private final Codec codec =

lucene/backward-codecs/src/test/org/apache/lucene/backward_codecs/lucene80/TestBestSpeedLucene80DocValuesFormat.java

@@ -17,9 +17,11 @@
 package org.apache.lucene.backward_codecs.lucene80;
 
 import org.apache.lucene.codecs.Codec;
+import org.apache.lucene.util.LuceneTestCase.Nightly;
 import org.apache.lucene.util.TestUtil;
 
 /** Tests Lucene80DocValuesFormat */
+@Nightly // N-2 formats are only tested on nightly runs
 public class TestBestSpeedLucene80DocValuesFormat extends BaseLucene80DocValuesFormatTestCase {
   private final Codec codec =
       TestUtil.alwaysDocValuesFormat(

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

@@ -39,8 +39,10 @@ import org.apache.lucene.index.SortedSetDocValues;
 import org.apache.lucene.store.Directory;
 import org.apache.lucene.util.BytesRef;
 import org.apache.lucene.util.LuceneTestCase;
+import org.apache.lucene.util.LuceneTestCase.Nightly;
 import org.apache.lucene.util.TestUtil;
 
+@Nightly // N-2 formats are only tested on nightly runs
 public class TestDocValuesCompression extends LuceneTestCase {
   private final Codec bestSpeed =
       TestUtil.alwaysDocValuesFormat(

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

@@ -29,9 +29,11 @@ import org.apache.lucene.util.BitSet;
 import org.apache.lucene.util.BitSetIterator;
 import org.apache.lucene.util.FixedBitSet;
 import org.apache.lucene.util.LuceneTestCase;
+import org.apache.lucene.util.LuceneTestCase.Nightly;
 import org.apache.lucene.util.SparseFixedBitSet;
 import org.apache.lucene.util.TestUtil;
 
+@Nightly // N-2 formats are only tested on nightly runs
 public class TestIndexedDISI extends LuceneTestCase {
 
   public void testEmpty() throws IOException {

lucene/backward-codecs/src/test/org/apache/lucene/backward_codecs/lucene80/TestLucene80NormsFormat.java

@@ -19,8 +19,10 @@ package org.apache.lucene.backward_codecs.lucene80;
 import org.apache.lucene.backward_codecs.lucene87.Lucene87RWCodec;
 import org.apache.lucene.codecs.Codec;
 import org.apache.lucene.index.BaseNormsFormatTestCase;
+import org.apache.lucene.util.LuceneTestCase.Nightly;
 
 /** Tests Lucene80NormsFormat */
+@Nightly // N-2 formats are only tested on nightly runs
 public class TestLucene80NormsFormat extends BaseNormsFormatTestCase {
   private final Codec codec = new Lucene87RWCodec();
 

lucene/backward-codecs/src/test/org/apache/lucene/backward_codecs/lucene80/TestLucene80NormsFormatMergeInstance.java

@@ -16,7 +16,10 @@
  */
 package org.apache.lucene.backward_codecs.lucene80;
 
+import org.apache.lucene.util.LuceneTestCase.Nightly;
+
 /** Test the merge instance of the Lucene80 norms format. */
+@Nightly // N-2 formats are only tested on nightly runs
 public class TestLucene80NormsFormatMergeInstance extends TestLucene80NormsFormat {
 
   @Override

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

@@ -26,9 +26,11 @@ import org.apache.lucene.store.IOContext;
 import org.apache.lucene.store.IndexInput;
 import org.apache.lucene.store.IndexOutput;
 import org.apache.lucene.util.LuceneTestCase;
+import org.apache.lucene.util.LuceneTestCase.Nightly;
 import org.apache.lucene.util.TestUtil;
 import org.apache.lucene.util.packed.PackedInts;
 
+@Nightly // N-2 formats are only tested on nightly runs
 public class TestForDeltaUtil extends LuceneTestCase {
 
   public void testEncodeDecode() throws IOException {

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

@@ -27,9 +27,11 @@ import org.apache.lucene.store.IndexInput;
 import org.apache.lucene.store.IndexOutput;
 import org.apache.lucene.util.ArrayUtil;
 import org.apache.lucene.util.LuceneTestCase;
+import org.apache.lucene.util.LuceneTestCase.Nightly;
 import org.apache.lucene.util.TestUtil;
 import org.apache.lucene.util.packed.PackedInts;
 
+@Nightly // N-2 formats are only tested on nightly runs
 public class TestForUtil extends LuceneTestCase {
 
   public void testEncodeDecode() throws IOException {

lucene/backward-codecs/src/test/org/apache/lucene/backward_codecs/lucene84/TestLucene84PostingsFormat.java

@@ -39,8 +39,10 @@ import org.apache.lucene.store.Directory;
 import org.apache.lucene.store.IOContext;
 import org.apache.lucene.store.IndexInput;
 import org.apache.lucene.store.IndexOutput;
+import org.apache.lucene.util.LuceneTestCase.Nightly;
 import org.apache.lucene.util.TestUtil;
 
+@Nightly // N-2 formats are only tested on nightly runs
 public class TestLucene84PostingsFormat extends BasePostingsFormatTestCase {
   private final Codec codec = TestUtil.alwaysPostingsFormat(new Lucene84RWPostingsFormat());
 

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

@@ -27,9 +27,11 @@ import org.apache.lucene.store.IndexInput;
 import org.apache.lucene.store.IndexOutput;
 import org.apache.lucene.util.ArrayUtil;
 import org.apache.lucene.util.LuceneTestCase;
+import org.apache.lucene.util.LuceneTestCase.Nightly;
 import org.apache.lucene.util.TestUtil;
 import org.apache.lucene.util.packed.PackedInts;
 
+@Nightly // N-2 formats are only tested on nightly runs
 public class TestPForUtil extends LuceneTestCase {
 
   public void testEncodeDecode() throws IOException {

lucene/backward-codecs/src/test/org/apache/lucene/backward_codecs/lucene86/TestLucene86PointsFormat.java

@@ -39,9 +39,11 @@ import org.apache.lucene.index.PointValues.Relation;
 import org.apache.lucene.index.SegmentReadState;
 import org.apache.lucene.index.SegmentWriteState;
 import org.apache.lucene.store.Directory;
+import org.apache.lucene.util.LuceneTestCase.Nightly;
 import org.apache.lucene.util.TestUtil;
 import org.apache.lucene.util.bkd.BKDConfig;
 
+@Nightly // N-2 formats are only tested on nightly runs
 public class TestLucene86PointsFormat extends BasePointsFormatTestCase {
 
   private final Codec codec;

lucene/backward-codecs/src/test/org/apache/lucene/backward_codecs/lucene86/TestLucene86SegmentInfoFormat.java

@@ -20,9 +20,10 @@ package org.apache.lucene.backward_codecs.lucene86;
 import org.apache.lucene.backward_codecs.lucene87.Lucene87RWCodec;
 import org.apache.lucene.codecs.Codec;
 import org.apache.lucene.index.BaseSegmentInfoFormatTestCase;
+import org.apache.lucene.util.LuceneTestCase.Nightly;
 import org.apache.lucene.util.Version;
 
-@SuppressWarnings("deprecation")
+@Nightly // N-2 formats are only tested on nightly runs
 public class TestLucene86SegmentInfoFormat extends BaseSegmentInfoFormatTestCase {
 
   @Override

lucene/backward-codecs/src/test/org/apache/lucene/backward_codecs/lucene87/TestLucene87StoredFieldsFormat.java

@@ -18,7 +18,9 @@ package org.apache.lucene.backward_codecs.lucene87;
 
 import org.apache.lucene.codecs.Codec;
 import org.apache.lucene.index.BaseStoredFieldsFormatTestCase;
+import org.apache.lucene.util.LuceneTestCase.Nightly;
 
+@Nightly // N-2 formats are only tested on nightly runs
 public class TestLucene87StoredFieldsFormat extends BaseStoredFieldsFormatTestCase {
   @Override
   protected Codec getCodec() {

lucene/backward-codecs/src/test/org/apache/lucene/backward_codecs/lucene87/TestLucene87StoredFieldsFormatHighCompression.java

@@ -25,7 +25,9 @@ import org.apache.lucene.index.DirectoryReader;
 import org.apache.lucene.index.IndexWriter;
 import org.apache.lucene.index.IndexWriterConfig;
 import org.apache.lucene.store.Directory;
+import org.apache.lucene.util.LuceneTestCase.Nightly;
 
+@Nightly // N-2 formats are only tested on nightly runs
 public class TestLucene87StoredFieldsFormatHighCompression extends BaseStoredFieldsFormatTestCase {
   @Override
   protected Codec getCodec() {

lucene/backward-codecs/src/test/org/apache/lucene/backward_codecs/lucene87/TestLucene87StoredFieldsFormatMergeInstance.java

@@ -16,7 +16,10 @@
  */
 package org.apache.lucene.backward_codecs.lucene87;
 
+import org.apache.lucene.util.LuceneTestCase.Nightly;
+
 /** Test the merge instance of the Lucene87 stored fields format. */
+@Nightly // N-2 formats are only tested on nightly runs
 public class TestLucene87StoredFieldsFormatMergeInstance extends TestLucene87StoredFieldsFormat {
 
   @Override

lucene/backward-codecs/src/test/org/apache/lucene/backward_codecs/packed/TestLegacyDirectMonotonic.java

@@ -29,8 +29,10 @@ import org.apache.lucene.store.IndexOutput;
 import org.apache.lucene.util.ArrayUtil;
 import org.apache.lucene.util.LongValues;
 import org.apache.lucene.util.LuceneTestCase;
+import org.apache.lucene.util.LuceneTestCase.Nightly;
 import org.apache.lucene.util.TestUtil;
 
+@Nightly // N-2 formats are only tested on nightly runs
 public class TestLegacyDirectMonotonic extends LuceneTestCase {
 
   public void testValidation() {

lucene/backward-codecs/src/test/org/apache/lucene/backward_codecs/packed/TestLegacyDirectPacked.java

@@ -25,8 +25,10 @@ import org.apache.lucene.store.IndexInput;
 import org.apache.lucene.store.IndexOutput;
 import org.apache.lucene.util.LongValues;
 import org.apache.lucene.util.LuceneTestCase;
+import org.apache.lucene.util.LuceneTestCase.Nightly;
 import org.apache.lucene.util.TestUtil;
 
+@Nightly // N-2 formats are only tested on nightly runs
 public class TestLegacyDirectPacked extends LuceneTestCase {
 
   /** simple encode/decode */

lucene/backward-codecs/src/test/org/apache/lucene/backward_codecs/packed/TestLegacyPackedInts.java

@@ -23,11 +23,13 @@ import org.apache.lucene.store.Directory;
 import org.apache.lucene.store.IndexInput;
 import org.apache.lucene.store.IndexOutput;
 import org.apache.lucene.util.LuceneTestCase;
+import org.apache.lucene.util.LuceneTestCase.Nightly;
 import org.apache.lucene.util.RamUsageTester;
 import org.apache.lucene.util.TestUtil;
 import org.apache.lucene.util.packed.PackedInts;
 import org.apache.lucene.util.packed.PackedInts.Reader;
 
+@Nightly // N-2 formats are only tested on nightly runs
 public class TestLegacyPackedInts extends LuceneTestCase {
 
   public void testPackedInts() throws IOException {

lucene/backward-codecs/src/test/org/apache/lucene/backward_codecs/store/EndiannessReverserTestCase.java

@@ -23,7 +23,9 @@ import org.apache.lucene.store.IndexInput;
 import org.apache.lucene.store.IndexOutput;
 import org.apache.lucene.store.RandomAccessInput;
 import org.apache.lucene.util.LuceneTestCase;
+import org.apache.lucene.util.LuceneTestCase.Nightly;
 
+@Nightly // N-2 formats are only tested on nightly runs
 public abstract class EndiannessReverserTestCase extends LuceneTestCase {
 
   protected abstract IndexInput getEndiannessReverserInput(

lucene/backward-codecs/src/test/org/apache/lucene/backward_codecs/store/TestEndiannessReverserCheckSumIndexInput.java

@@ -21,7 +21,9 @@ import org.apache.lucene.store.Directory;
 import org.apache.lucene.store.IOContext;
 import org.apache.lucene.store.IndexInput;
 import org.apache.lucene.store.IndexOutput;
+import org.apache.lucene.util.LuceneTestCase.Nightly;
 
+@Nightly // N-2 formats are only tested on nightly runs
 public class TestEndiannessReverserCheckSumIndexInput extends EndiannessReverserTestCase {
 
   @Override

lucene/backward-codecs/src/test/org/apache/lucene/backward_codecs/store/TestEndiannessReverserIndexInput.java

@@ -21,7 +21,9 @@ import org.apache.lucene.store.Directory;
 import org.apache.lucene.store.IOContext;
 import org.apache.lucene.store.IndexInput;
 import org.apache.lucene.store.IndexOutput;
+import org.apache.lucene.util.LuceneTestCase.Nightly;
 
+@Nightly // N-2 formats are only tested on nightly runs
 public class TestEndiannessReverserIndexInput extends EndiannessReverserTestCase {
 
   @Override

lucene/backward-codecs/src/test/org/apache/lucene/backward_index/TestBackwardsCompatibility.java

@@ -1015,6 +1015,7 @@ public class TestBackwardsCompatibility extends LuceneTestCase {
       searchIndex(oldIndexDirs.get(name), name, Version.MIN_SUPPORTED_MAJOR);
     }
 
+    if (TEST_NIGHTLY) {
       for (String name : binarySupportedNames) {
         Path oldIndexDir = createTempDir(name);
         TestUtil.unzip(getDataInputStream("unsupported." + name + ".zip"), oldIndexDir);
@@ -1023,6 +1024,7 @@ public class TestBackwardsCompatibility extends LuceneTestCase {
         }
       }
     }
+  }
 
   public void testIndexOldIndexNoAdds() throws IOException {
     for (String name : oldNames) {
@@ -2080,6 +2082,7 @@ public class TestBackwardsCompatibility extends LuceneTestCase {
     }
   }
 
+  @Nightly
   public void testReadNMinusTwoCommit() throws IOException {
     for (String name : binarySupportedNames) {
       Path oldIndexDir = createTempDir(name);

lucene/test-framework/src/java/org/apache/lucene/index/BaseCompoundFormatTestCase.java

@@ -165,6 +165,7 @@ public abstract class BaseCompoundFormatTestCase extends BaseIndexFileFormatTest
   }
 
   // LUCENE-5724: actually test we play nice with NRTCachingDir and massive file
+  @Slow
   public void testLargeCFS() throws IOException {
     final String testfile = "_123.test";
     IOContext context = new IOContext(new FlushInfo(0, 512 * 1024 * 1024));