From 01e34f8723559f6770c63dc17cafb4a0313030a8 Mon Sep 17 00:00:00 2001
From: Peter Gromov <peter@jetbrains.com>
Date: Thu, 11 Feb 2021 15:12:58 +0100
Subject: [PATCH] LUCENE-9764: Hunspell: try title case as FORCEUCASE
 misspelled word suggestions (#2352)

---
 .../org/apache/lucene/analysis/hunspell/SpellChecker.java  | 7 +++++++
 .../org/apache/lucene/analysis/hunspell/forceucase.sug     | 2 ++
 2 files changed, 9 insertions(+)
 create mode 100644 lucene/analysis/common/src/test/org/apache/lucene/analysis/hunspell/forceucase.sug

diff --git a/lucene/analysis/common/src/java/org/apache/lucene/analysis/hunspell/SpellChecker.java b/lucene/analysis/common/src/java/org/apache/lucene/analysis/hunspell/SpellChecker.java
index 97dea149a51..11c05406d07 100644
--- a/lucene/analysis/common/src/java/org/apache/lucene/analysis/hunspell/SpellChecker.java
+++ b/lucene/analysis/common/src/java/org/apache/lucene/analysis/hunspell/SpellChecker.java
@@ -430,6 +430,13 @@ public class SpellChecker {
     }
 
     WordCase wordCase = WordCase.caseOf(word);
+    if (dictionary.forceUCase != FLAG_UNSET && wordCase == WordCase.LOWER) {
+      String title = dictionary.toTitleCase(word);
+      if (spell(title)) {
+        return Collections.singletonList(title);
+      }
+    }
+
     SpellChecker suggestionSpeller =
         new SpellChecker(dictionary) {
           @Override
diff --git a/lucene/analysis/common/src/test/org/apache/lucene/analysis/hunspell/forceucase.sug b/lucene/analysis/common/src/test/org/apache/lucene/analysis/hunspell/forceucase.sug
new file mode 100644
index 00000000000..6a77cbd06d0
--- /dev/null
+++ b/lucene/analysis/common/src/test/org/apache/lucene/analysis/hunspell/forceucase.sug
@@ -0,0 +1,2 @@
+Foobaz
+Foobarbaz