From fdb1e2051fa6478b826d22a20a7bfbc4082d0362 Mon Sep 17 00:00:00 2001
From: Stefan Oehme <st.oehme@gmail.com>
Date: Fri, 19 Nov 2021 19:42:36 +0100
Subject: [PATCH] Don't reprocess aggregated types when there's nothing to
 compile

Fixes https://github.com/micronaut-projects/micronaut-core/issues/6536

Signed-off-by: Stefan Oehme <st.oehme@gmail.com>
---
 ...alAnnotationProcessingIntegrationTest.groovy |  6 +++++-
 ...alAnnotationProcessingIntegrationTest.groovy | 17 +++++++++++++++++
 .../incremental/deps/ClassSetAnalysis.java      |  3 +++
 3 files changed, 25 insertions(+), 1 deletion(-)

diff --git a/subprojects/language-java/src/integTest/groovy/org/gradle/api/tasks/compile/AbstractIncrementalAnnotationProcessingIntegrationTest.groovy b/subprojects/language-java/src/integTest/groovy/org/gradle/api/tasks/compile/AbstractIncrementalAnnotationProcessingIntegrationTest.groovy
index f0f309cf0006..1703b9772c43 100644
--- a/subprojects/language-java/src/integTest/groovy/org/gradle/api/tasks/compile/AbstractIncrementalAnnotationProcessingIntegrationTest.groovy
+++ b/subprojects/language-java/src/integTest/groovy/org/gradle/api/tasks/compile/AbstractIncrementalAnnotationProcessingIntegrationTest.groovy
@@ -21,6 +21,7 @@ import org.gradle.integtests.fixtures.CompilationOutputsFixture
 import org.gradle.language.fixtures.AnnotationProcessorFixture
 import org.gradle.language.fixtures.CompileJavaBuildOperationsFixture
 import org.gradle.test.fixtures.file.TestFile
+import org.intellij.lang.annotations.Language
 
 abstract class AbstractIncrementalAnnotationProcessingIntegrationTest extends AbstractIntegrationSpec {
 
@@ -53,6 +54,9 @@ abstract class AbstractIncrementalAnnotationProcessingIntegrationTest extends Ab
             dependencies {
                 compileOnly project(":annotation")
                 annotationProcessor project(":processor")
+
+                testCompileOnly project(":annotation")
+                testAnnotationProcessor project(":processor")
             }
         """
 
@@ -70,7 +74,7 @@ abstract class AbstractIncrementalAnnotationProcessingIntegrationTest extends Ab
         processor.writeAnnotationProcessorTo(processorProjectDir)
     }
 
-    protected final File java(String... classBodies) {
+    protected final File java(@Language("java") String... classBodies) {
         javaInPackage('', classBodies)
     }
 
diff --git a/subprojects/language-java/src/integTest/groovy/org/gradle/api/tasks/compile/AggregatingIncrementalAnnotationProcessingIntegrationTest.groovy b/subprojects/language-java/src/integTest/groovy/org/gradle/api/tasks/compile/AggregatingIncrementalAnnotationProcessingIntegrationTest.groovy
index f35b4bdce7ec..f6558187f78e 100644
--- a/subprojects/language-java/src/integTest/groovy/org/gradle/api/tasks/compile/AggregatingIncrementalAnnotationProcessingIntegrationTest.groovy
+++ b/subprojects/language-java/src/integTest/groovy/org/gradle/api/tasks/compile/AggregatingIncrementalAnnotationProcessingIntegrationTest.groovy
@@ -436,6 +436,23 @@ class AggregatingIncrementalAnnotationProcessingIntegrationTest extends Abstract
         succeeds "compileJava"
     }
 
+    @Issue("https://https://github.com/micronaut-projects/micronaut-core/issues/6536")
+    def "does not reprocess if nothing in the current sourceSet changed"() {
+        given:
+        withProcessor(new AnnotatedGeneratedClassProcessorFixture())
+        javaTestSourceFile "@Bean class Test {}"
+        outputs.snapshot { succeeds "compileTestJava" }
+
+        when:
+        java "class Unrelated {}"
+
+        then:
+        succeeds "compileTestJava"
+
+        and:
+        outputs.recompiledClasses("Unrelated")
+    }
+
     private boolean serviceRegistryReferences(String... services) {
         def registry = file("build/classes/java/main/ServiceRegistryResource.txt").text
         services.every() {
diff --git a/subprojects/language-java/src/main/java/org/gradle/api/internal/tasks/compile/incremental/deps/ClassSetAnalysis.java b/subprojects/language-java/src/main/java/org/gradle/api/internal/tasks/compile/incremental/deps/ClassSetAnalysis.java
index 96bd0434c401..d16862dccc4a 100644
--- a/subprojects/language-java/src/main/java/org/gradle/api/internal/tasks/compile/incremental/deps/ClassSetAnalysis.java
+++ b/subprojects/language-java/src/main/java/org/gradle/api/internal/tasks/compile/incremental/deps/ClassSetAnalysis.java
@@ -157,6 +157,9 @@ private DependentsSet findDirectDependents(String className) {
      * - the originating types of generated classes that need to be recompiled, since they wouldn't exist if the originating type is not reprocessed
      */
     public Set<String> getTypesToReprocess(Set<String> compiledClasses) {
+        if (compiledClasses.isEmpty()) {
+            return Collections.emptySet();
+        }
         Set<String> typesToReprocess = new HashSet<>(annotationProcessingData.getAggregatedTypes());
         for (Map.Entry<String, Set<String>> entry : annotationProcessingData.getGeneratedTypesByOrigin().entrySet()) {
             if (entry.getValue().stream().anyMatch(compiledClasses::contains)) {