From 8de4fc830ff86510e7602b24e7361abcd8dacc73 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?An=C5=BEe=20Sodja?= <asodja@gradle.com>
Date: Thu, 9 Dec 2021 22:50:05 +0100
Subject: [PATCH] Fix incremental compilation for classes with $ in name

Fixes #19257
---
 ...avaGroovyIncrementalCompilationSupport.groovy |  2 +-
 ...eIncrementalCompilationIntegrationTest.groovy | 16 ++++++++++++++++
 .../FileNameDerivingClassNameConverter.java      | 15 +++++++++++++--
 3 files changed, 30 insertions(+), 3 deletions(-)

diff --git a/subprojects/language-java/src/integTest/groovy/org/gradle/java/compile/incremental/AbstractJavaGroovyIncrementalCompilationSupport.groovy b/subprojects/language-java/src/integTest/groovy/org/gradle/java/compile/incremental/AbstractJavaGroovyIncrementalCompilationSupport.groovy
index b2a8b60ca4cd..ce258588813d 100644
--- a/subprojects/language-java/src/integTest/groovy/org/gradle/java/compile/incremental/AbstractJavaGroovyIncrementalCompilationSupport.groovy
+++ b/subprojects/language-java/src/integTest/groovy/org/gradle/java/compile/incremental/AbstractJavaGroovyIncrementalCompilationSupport.groovy
@@ -29,7 +29,7 @@ abstract class AbstractJavaGroovyIncrementalCompilationSupport extends AbstractI
     File source(String... classBodies) {
         File out
         for (String body : classBodies) {
-            def className = (body =~ /(?s).*?(?:class|interface|enum) (\w+) .*/)[0][1]
+            def className = (body =~ /(?s).*?(?:class|interface|enum) ([\w$]+) .*/)[0][1]
             assert className: "unable to find class name"
             def f = file("src/main/${language.name}/${className}.${language.name}")
             f.createFile()
diff --git a/subprojects/language-java/src/integTest/groovy/org/gradle/java/compile/incremental/AbstractSourceIncrementalCompilationIntegrationTest.groovy b/subprojects/language-java/src/integTest/groovy/org/gradle/java/compile/incremental/AbstractSourceIncrementalCompilationIntegrationTest.groovy
index fd0923ca5184..4e5b432398d1 100644
--- a/subprojects/language-java/src/integTest/groovy/org/gradle/java/compile/incremental/AbstractSourceIncrementalCompilationIntegrationTest.groovy
+++ b/subprojects/language-java/src/integTest/groovy/org/gradle/java/compile/incremental/AbstractSourceIncrementalCompilationIntegrationTest.groovy
@@ -492,4 +492,20 @@ sourceSets {
         then:
         failureCauseContains('Compilation failed')
     }
+
+    def "recompiles classes with \$ in class name after rename"() {
+        def firstSource = source "class Class\$Name {}"
+        source "class Main { public static void main(String[] args) { new Class\$Name(); } }"
+        outputs.snapshot { run language.compileTaskName }
+
+        when:
+        firstSource.delete()
+        source "class Class\$Name1 {}",
+            "class Main { public static void main(String[] args) { new Class\$Name1(); } }"
+        run language.compileTaskName
+
+        then:
+        outputs.deletedClasses("Class\$Name")
+        outputs.recompiledClasses("Class\$Name1", "Main")
+    }
 }
diff --git a/subprojects/language-java/src/main/java/org/gradle/api/internal/tasks/compile/incremental/recomp/FileNameDerivingClassNameConverter.java b/subprojects/language-java/src/main/java/org/gradle/api/internal/tasks/compile/incremental/recomp/FileNameDerivingClassNameConverter.java
index 250cc77bdc60..b0410c073bc8 100644
--- a/subprojects/language-java/src/main/java/org/gradle/api/internal/tasks/compile/incremental/recomp/FileNameDerivingClassNameConverter.java
+++ b/subprojects/language-java/src/main/java/org/gradle/api/internal/tasks/compile/incremental/recomp/FileNameDerivingClassNameConverter.java
@@ -56,9 +56,20 @@ public Set<String> getRelativeSourcePaths(String className) {
             return sourcePaths;
         }
 
+        Set<String> paths = fileExtensions.stream()
+            .map(fileExtension -> className.replace('.', '/') + fileExtension)
+            .collect(Collectors.toSet());
+
+        // Classes with $ may be inner classes
         int innerClassIdx = className.indexOf("$");
-        String baseName = innerClassIdx > 0 ? className.substring(0, innerClassIdx) : className;
-        return fileExtensions.stream().map(fileExtension -> baseName.replace('.', '/') + fileExtension).collect(Collectors.toSet());
+        if (innerClassIdx > 0) {
+            String baseName = className.substring(0, innerClassIdx);
+            paths.addAll(fileExtensions.stream()
+                .map(fileExtension -> baseName.replace('.', '/') + fileExtension)
+                .collect(Collectors.toSet()));
+        }
+
+        return paths;
     }
 
 }