From 4240159b44c6b3549c8dacab69748e7aaee3bfa4 Mon Sep 17 00:00:00 2001
From: Adrien Grand <jpountz@gmail.com>
Date: Wed, 18 May 2022 23:31:47 +0200
Subject: [PATCH] LUCENE-10574: Fix test failure.

If a LogByteSizeMergePolicy is used, then it might decide to not merge the two
one-document segments if their on-disk sizes are too different. Using a
LogDocMergePolicy addresses the issue as both segments are always considered
the same size.
---
 .../org/apache/lucene/index/TestIndexWriterOnDiskFull.java    | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/lucene/core/src/test/org/apache/lucene/index/TestIndexWriterOnDiskFull.java b/lucene/core/src/test/org/apache/lucene/index/TestIndexWriterOnDiskFull.java
index 4001fb982ba..0847ff63fd1 100644
--- a/lucene/core/src/test/org/apache/lucene/index/TestIndexWriterOnDiskFull.java
+++ b/lucene/core/src/test/org/apache/lucene/index/TestIndexWriterOnDiskFull.java
@@ -539,6 +539,8 @@ public class TestIndexWriterOnDiskFull extends LuceneTestCase {
     MockDirectoryWrapper dir = newMockDirectory();
     // IndexWriter w = new IndexWriter(dir, newIndexWriterConfig(new
     // MockAnalyzer(random)).setReaderPooling(true));
+    LogDocMergePolicy mp = new LogDocMergePolicy();
+    mp.setMergeFactor(2);
     IndexWriter w =
         new IndexWriter(
             dir,
@@ -546,7 +548,7 @@ public class TestIndexWriterOnDiskFull extends LuceneTestCase {
                 .setMergeScheduler(new SerialMergeScheduler())
                 .setReaderPooling(true)
                 .setMergePolicy(
-                    new FilterMergePolicy(newLogMergePolicy(2)) {
+                    new FilterMergePolicy(mp) {
                       @Override
                       public boolean keepFullyDeletedSegment(
                           IOSupplier<CodecReader> readerIOSupplier) throws IOException {