LUCENE-9827: Propagate `numChunks` through bulk merges for term vectors as well.

This commit also adds more checks about the values of `numChunks`,
`numDirtyChunks` and `numDirtyDocs` that would have helped discover this issue
earlier.

lucene/core/src/java/org/apache/lucene/codecs/lucene90/compressing/Lucene90CompressingStoredFieldsReader.java

@@ -178,6 +178,31 @@ public final class Lucene90CompressingStoredFieldsReader extends StoredFieldsRea
       numDirtyChunks = metaIn.readVLong();
       numDirtyDocs = metaIn.readVLong();
 
+      if (numChunks < numDirtyChunks) {
+        throw new CorruptIndexException(
+            "Cannot have more dirty chunks than chunks: numChunks="
+                + numChunks
+                + ", numDirtyChunks="
+                + numDirtyChunks,
+            metaIn);
+      }
+      if ((numDirtyChunks == 0) != (numDirtyDocs == 0)) {
+        throw new CorruptIndexException(
+            "Cannot have dirty chunks without dirty docs or vice-versa: numDirtyChunks="
+                + numDirtyChunks
+                + ", numDirtyDocs="
+                + numDirtyDocs,
+            metaIn);
+      }
+      if (numDirtyDocs < numDirtyChunks) {
+        throw new CorruptIndexException(
+            "Cannot have more dirty chunks than documents within dirty chunks: numDirtyChunks="
+                + numDirtyChunks
+                + ", numDirtyDocs="
+                + numDirtyDocs,
+            metaIn);
+      }
+
       CodecUtil.checkFooter(metaIn, null);
       metaIn.close();
 

lucene/core/src/java/org/apache/lucene/codecs/lucene90/compressing/Lucene90CompressingTermVectorsReader.java

@@ -173,6 +173,31 @@ public final class Lucene90CompressingTermVectorsReader extends TermVectorsReade
       numDirtyChunks = metaIn.readVLong();
       numDirtyDocs = metaIn.readVLong();
 
+      if (numChunks < numDirtyChunks) {
+        throw new CorruptIndexException(
+            "Cannot have more dirty chunks than chunks: numChunks="
+                + numChunks
+                + ", numDirtyChunks="
+                + numDirtyChunks,
+            metaIn);
+      }
+      if ((numDirtyChunks == 0) != (numDirtyDocs == 0)) {
+        throw new CorruptIndexException(
+            "Cannot have dirty chunks without dirty docs or vice-versa: numDirtyChunks="
+                + numDirtyChunks
+                + ", numDirtyDocs="
+                + numDirtyDocs,
+            metaIn);
+      }
+      if (numDirtyDocs < numDirtyChunks) {
+        throw new CorruptIndexException(
+            "Cannot have more dirty chunks than documents within dirty chunks: numDirtyChunks="
+                + numDirtyChunks
+                + ", numDirtyDocs="
+                + numDirtyDocs,
+            metaIn);
+      }
+
       decompressor = compressionMode.newDecompressor();
       this.reader =
           new BlockPackedReaderIterator(vectorsStream, packedIntsVersion, PACKED_BLOCK_SIZE, 0);

lucene/core/src/java/org/apache/lucene/codecs/lucene90/compressing/Lucene90CompressingTermVectorsWriter.java

@@ -904,6 +904,7 @@ public final class Lucene90CompressingTermVectorsWriter extends TermVectorsWrite
         }
 
         // since we bulk merged all chunks, we inherit any dirty ones from this segment.
+        numChunks += matchingVectorsReader.getNumChunks();
         numDirtyChunks += matchingVectorsReader.getNumDirtyChunks();
         numDirtyDocs += matchingVectorsReader.getNumDirtyDocs();
       } else {