From 10b68df2688d433ba53788182cd4685b03135fed Mon Sep 17 00:00:00 2001
From: Ilia Permiashkin <ilia.permiashkin@jetbrains.com>
Date: Mon, 30 Jun 2025 17:18:06 +0000
Subject: [PATCH] IJPL-194260 Umlauts in code names cause spellchecker false
 positive

Merge-request: IJ-MR-167314
Merged-by: Ilia Permiashkin <ilia.permiashkin@jetbrains.com>

GitOrigin-RevId: 8b35392555b59cf4c94e8767acdb46218fe57668
---
 .../jetbrains/kotlin/idea/grazie/KotlinGrazieSupportTest.kt  | 4 ++++
 plugins/kotlin/idea/tests/testData/grazie/Umlauts.kt         | 5 +++++
 .../spellchecker/inspections/IdentifierSplitter.java         | 2 +-
 3 files changed, 10 insertions(+), 1 deletion(-)
 create mode 100644 plugins/kotlin/idea/tests/testData/grazie/Umlauts.kt

diff --git a/plugins/kotlin/idea/tests/test/org/jetbrains/kotlin/idea/grazie/KotlinGrazieSupportTest.kt b/plugins/kotlin/idea/tests/test/org/jetbrains/kotlin/idea/grazie/KotlinGrazieSupportTest.kt
index e8a36088eef4..1d7a7c0cc88b 100644
--- a/plugins/kotlin/idea/tests/test/org/jetbrains/kotlin/idea/grazie/KotlinGrazieSupportTest.kt
+++ b/plugins/kotlin/idea/tests/test/org/jetbrains/kotlin/idea/grazie/KotlinGrazieSupportTest.kt
@@ -28,6 +28,10 @@ class KotlinGrazieSupportTest28 : GrazieTestBase() {
         runHighlightTestForFile("grazie/StringLiterals.kt")
     }
 
+    fun `test umlauts doesn't produce false positives`() {
+        runHighlightTestForFile("grazie/Umlauts.kt")
+    }
+
     fun `test text extraction in string literals`() {
         val file = myFixture.configureByText("a.kt", "val s = \"foo $" + "{injection} bar\" ")
         val content = TextExtractor.findTextAt(file, 10, TextContent.TextDomain.ALL)
diff --git a/plugins/kotlin/idea/tests/testData/grazie/Umlauts.kt b/plugins/kotlin/idea/tests/testData/grazie/Umlauts.kt
new file mode 100644
index 000000000000..12f0841f365c
--- /dev/null
+++ b/plugins/kotlin/idea/tests/testData/grazie/Umlauts.kt
@@ -0,0 +1,5 @@
+package ide.language.kotlin
+
+fun `ähnliche Werte sollen gruppiert werden`() {
+
+}
\ No newline at end of file
diff --git a/spellchecker/src/com/intellij/spellchecker/inspections/IdentifierSplitter.java b/spellchecker/src/com/intellij/spellchecker/inspections/IdentifierSplitter.java
index eda966174711..d6e03c0b1160 100644
--- a/spellchecker/src/com/intellij/spellchecker/inspections/IdentifierSplitter.java
+++ b/spellchecker/src/com/intellij/spellchecker/inspections/IdentifierSplitter.java
@@ -20,7 +20,7 @@ public class IdentifierSplitter extends BaseSplitter {
     return INSTANCE;
   }
 
-  private static final @NonNls Pattern WORD = Pattern.compile("\\b\\p{L}*'?\\p{L}*");
+  private static final @NonNls Pattern WORD = Pattern.compile("(?U)\\b\\p{L}*'?\\p{L}*");
   private static final @NonNls Pattern WORD_IN_QUOTES = Pattern.compile("'([^']*)'");
 
   @Override