From 316df22e55e95a10ce0005c70357e44f13f5d858 Mon Sep 17 00:00:00 2001
From: martinfrancois <f.martin@fastmail.com>
Date: Tue, 11 Aug 2026 20:09:54 +0200
Subject: [PATCH] RenameUnderscoreIdentifier: add failing tests for cross-file
 class rename gaps

classReferencesInAnotherSourceFileFollowTheRename pins that a class rename
leaves references in other source files on the old, invalid _ spelling.
classRenameAvoidsASecondaryClassDeclaredInAnotherSourceFile pins that the
chosen name duplicates a package private class from a differently named file.
Both are marked known-failing with @ExpectedToFail.
---
 .../lang/RenameUnderscoreIdentifierTest.java  | 68 +++++++++++++++++++
 1 file changed, 68 insertions(+)

diff --git a/src/test/java/org/openrewrite/java/migrate/lang/RenameUnderscoreIdentifierTest.java b/src/test/java/org/openrewrite/java/migrate/lang/RenameUnderscoreIdentifierTest.java
index d29ad4f73b..6ffff12ae1 100644
--- a/src/test/java/org/openrewrite/java/migrate/lang/RenameUnderscoreIdentifierTest.java
+++ b/src/test/java/org/openrewrite/java/migrate/lang/RenameUnderscoreIdentifierTest.java
@@ -16,10 +16,12 @@
 package org.openrewrite.java.migrate.lang;
 
 import org.junit.jupiter.api.Test;
+import org.junitpioneer.jupiter.ExpectedToFail;
 import org.openrewrite.DocumentExample;
 import org.openrewrite.ExecutionContext;
 import org.openrewrite.Recipe;
 import org.openrewrite.TreeVisitor;
+import org.openrewrite.java.ChangeType;
 import org.openrewrite.test.RecipeSpec;
 import org.openrewrite.test.RewriteTest;
 
@@ -327,4 +329,70 @@ int count(List<String> items) {
           )
         );
     }
+
+    @ExpectedToFail("References to the renamed class in other source files keep the old `_` spelling")
+    @Test
+    void classReferencesInAnotherSourceFileFollowTheRename() {
+        rewriteRun(
+          spec -> spec.recipes(new ChangeType("UNDERSCORE", "_", false), new RenameUnderscoreIdentifier())
+            .allSources(s -> s.markers(javaVersion(8))),
+          //language=java
+          java(
+            """
+              class UNDERSCORE {
+              }
+              """,
+            """
+              class __ {
+              }
+              """,
+            spec -> spec.path("_.java")
+          ),
+          //language=java
+          java(
+            """
+              class User {
+                  UNDERSCORE field = new UNDERSCORE();
+              }
+              """,
+            """
+              class User {
+                  __ field = new __();
+              }
+              """
+          )
+        );
+    }
+
+    @ExpectedToFail("The chosen name duplicates a package private class declared in a differently named file")
+    @Test
+    void classRenameAvoidsASecondaryClassDeclaredInAnotherSourceFile() {
+        rewriteRun(
+          spec -> spec.recipes(new ChangeType("UNDERSCORE", "_", false), new RenameUnderscoreIdentifier())
+            .allSources(s -> s.markers(javaVersion(8))),
+          //language=java
+          java(
+            """
+              class UNDERSCORE {
+              }
+              """,
+            """
+              class _ {
+              }
+              """,
+            spec -> spec.path("_.java")
+          ),
+          //language=java
+          java(
+            """
+              class Other {
+              }
+
+              class __ {
+              }
+              """,
+            spec -> spec.path("Other.java")
+          )
+        );
+    }
 }