#2522: mockito-inline & Groovy NullPointerException

settings.gradle.kts

@@ -6,6 +6,7 @@ include("inline",
     "proxy",
     "extTest",
     "groovyTest",
+    "groovyInlineTest",
     "kotlinTest",
     "kotlinReleaseCoroutinesTest",
     "android",

src/main/java/org/mockito/internal/creation/bytebuddy/BytecodeGenerator.java

@@ -4,6 +4,12 @@
  */
 package org.mockito.internal.creation.bytebuddy;
 
+import net.bytebuddy.description.method.MethodDescription;
+import net.bytebuddy.matcher.ElementMatcher;
+
+import static net.bytebuddy.matcher.ElementMatchers.*;
+import static net.bytebuddy.matcher.ElementMatchers.named;
+
 public interface BytecodeGenerator {
 
     <T> Class<? extends T> mockClass(MockFeatures<T> features);
@@ -13,4 +19,16 @@ public interface BytecodeGenerator {
     void mockClassStatic(Class<?> type);
 
     default void clearAllCaches() {}
+
+    static ElementMatcher<MethodDescription> isGroovyMethod(boolean inline) {
+        ElementMatcher.Junction<MethodDescription> matcher =
+                isDeclaredBy(named("groovy.lang.GroovyObjectSupport"))
+                        .or(isAnnotatedWith(named("groovy.transform.Internal")));
+        if (inline) {
+            return matcher.or(
+                    named("$getStaticMetaClass").and(returns(named("groovy.lang.MetaClass"))));
+        } else {
+            return matcher;
+        }
+    }
 }

src/main/java/org/mockito/internal/creation/bytebuddy/InlineBytecodeGenerator.java

@@ -117,15 +117,19 @@ public InlineBytecodeGenerator(
                                                                 .or(isEquals())
                                                                 .or(isDefaultFinalizer())))
                                         .and(
-                                                not(
-                                                        isDeclaredBy(nameStartsWith("java."))
+                                                not(isDeclaredBy(nameStartsWith("java."))
                                                                 .<MethodDescription>and(
-                                                                        isPackagePrivate()))),
+                                                                        isPackagePrivate()))
+                                                        .and(
+                                                                not(
+                                                                        BytecodeGenerator
+                                                                                .isGroovyMethod(
+                                                                                        true)))),
                                 Advice.withCustomMapping()
                                         .bind(MockMethodAdvice.Identifier.class, identifier)
                                         .to(MockMethodAdvice.class))
                         .method(
-                                isStatic(),
+                                isStatic().and(not(BytecodeGenerator.isGroovyMethod(true))),
                                 Advice.withCustomMapping()
                                         .bind(MockMethodAdvice.Identifier.class, identifier)
                                         .to(MockMethodAdvice.ForStatic.class))
@@ -387,6 +391,7 @@ public byte[] transform(
                                 //            ,ClassFileLocator.ForClassLoader.ofSystemLoader()
                                 //        )
                                 )
+                        .ignoreAlso(BytecodeGenerator.isGroovyMethod())
                         // Note: The VM erases parameter meta data from the provided class file
                         // (bug). We just add this information manually.
                         .visit(new ParameterWritingVisitorWrapper(classBeingRedefined))

src/main/java/org/mockito/internal/creation/bytebuddy/SubclassBytecodeGenerator.java

@@ -224,7 +224,7 @@ public <T> Class<? extends T> mockClass(MockFeatures<T> features) {
                 byteBuddy
                         .subclass(features.mockedType)
                         .name(name)
-                        .ignoreAlso(isGroovyMethod())
+                        .ignoreAlso(BytecodeGenerator.isGroovyMethod(false))
                         .annotateType(
                                 features.stripAnnotations
                                         ? new Annotation[0]
@@ -293,11 +293,6 @@ private <T> Collection<Class<? super T>> getAllTypes(Class<T> type) {
         return supertypes;
     }
 
-    private static ElementMatcher<MethodDescription> isGroovyMethod() {
-        return isDeclaredBy(named("groovy.lang.GroovyObjectSupport"))
-                .or(isAnnotatedWith(named("groovy.transform.Internal")));
-    }
-
     private boolean isComingFromJDK(Class<?> type) {
         // Comes from the manifest entry :
         // Implementation-Title: Java Runtime Environment

subprojects/groovyInlineTest/groovyInlineTest.gradle

@@ -0,0 +1,11 @@
+apply plugin: 'groovy'
+
+description = "Integration test for using mockito-inline with Groovy."
+
+apply from: "$rootDir/gradle/dependencies.gradle"
+
+dependencies {
+    testImplementation project(":inline")
+    testImplementation libraries.groovy
+    testImplementation libraries.junit4
+}

subprojects/groovyInlineTest/src/test/groovy/org/mockito/groovy/GroovyMockitoTest.groovy

@@ -0,0 +1,46 @@
+/*
+ * Copyright (c) 2022 Mockito contributors
+ * This program is made available under the terms of the MIT License.
+ */
+package org.mockito.groovy
+
+import org.junit.Test
+import org.junit.runner.RunWith
+import org.mockito.InjectMocks
+import org.mockito.Mock
+import org.mockito.junit.MockitoJUnitRunner
+
+import static org.mockito.Mockito.verify
+
+@RunWith(MockitoJUnitRunner)
+class GroovyMockitoTest {
+
+    @Mock Helper helper
+    @InjectMocks ClassUnderTest classUnderTest
+
+    /**
+     * Test that the Groovy class under test can call methods on a mocked Groovy
+     * helper class.
+     */
+    @Test
+    void testCallGroovyFromGroovy() {
+        classUnderTest.methodUnderTest()
+        verify(helper).helperMethod()
+    }
+
+    static class ClassUnderTest {
+        private final Helper helper
+
+        ClassUnderTest(Helper helper) {
+            this.helper = helper
+        }
+
+        void methodUnderTest() {
+            helper.helperMethod()
+        }
+    }
+
+    static class Helper {
+        void helperMethod() { }
+    }
+}