Make it easier to support @CopyAnnotations in AutoValueExtensions

AutoValueExtension.Context now provides methods to lookup the annotations that should be copied to the class or methods.

RELNOTES=Make it easier to support @CopyAnnotations in AutoValueExtensions
PiperOrigin-RevId: 495638296

Author: java-team-github-bot

value/src/main/java/com/google/auto/value/extension/AutoValueExtension.java

@@ -15,13 +15,16 @@
  */
 package com.google.auto.value.extension;
 
+import com.google.common.collect.ImmutableList;
 import com.google.common.collect.ImmutableSet;
+import java.util.List;
 import java.util.Map;
 import java.util.Optional;
 import java.util.Set;
 import javax.annotation.processing.ProcessingEnvironment;
 import javax.annotation.processing.Processor;
 import javax.annotation.processing.SupportedOptions;
+import javax.lang.model.element.AnnotationMirror;
 import javax.lang.model.element.ExecutableElement;
 import javax.lang.model.element.TypeElement;
 import javax.lang.model.type.TypeMirror;
@@ -156,6 +159,32 @@ default Map<String, TypeMirror> propertyTypes() {
      */
     Set<ExecutableElement> abstractMethods();
 
+    /**
+     * Returns the complete list of annotations defined on the {@code classToCopyFrom} that should
+     * be added to any generated subclass. Only annotations visible to the {@code @AutoValue} will
+     * be present. See {@link com.google.auto.value.AutoValue.CopyAnnotations
+     * AutoValue.CopyAnnotations} for more information.
+     *
+     * <p>The default implementation of this method returns an empty list for compatibility with
+     * extensions which may have implemented this interface themselves.
+     */
+    default List<AnnotationMirror> classAnnotationsToCopy(TypeElement classToCopyFrom) {
+      return ImmutableList.of();
+    }
+
+    /**
+     * Returns the complete list of annotations defined on the {@code method} that should be applied
+     * to any override of that method. Only annotations visible to the {@code @AutoValue} will be
+     * present. See {@link com.google.auto.value.AutoValue.CopyAnnotations
+     * AutoValue.CopyAnnotations} for more information.
+     *
+     * <p>The default implementation of this method returns an empty list for compatibility with
+     * extensions which may have implemented this interface themselves.
+     */
+    default List<AnnotationMirror> methodAnnotationsToCopy(ExecutableElement method) {
+      return ImmutableList.of();
+    }
+
     /**
      * Returns a representation of the {@code Builder} associated with the {@code @AutoValue} class,
      * if there is one.

value/src/main/java/com/google/auto/value/extension/memoized/processor/MemoizeExtension.java

@@ -15,10 +15,7 @@
  */
 package com.google.auto.value.extension.memoized.processor;
 
-import static com.google.auto.common.AnnotationMirrors.getAnnotationValue;
 import static com.google.auto.common.GeneratedAnnotationSpecs.generatedAnnotationSpec;
-import static com.google.auto.common.MoreElements.getPackage;
-import static com.google.auto.common.MoreElements.isAnnotationPresent;
 import static com.google.auto.common.MoreStreams.toImmutableList;
 import static com.google.auto.common.MoreStreams.toImmutableSet;
 import static com.google.auto.value.extension.memoized.processor.ClassNames.MEMOIZED_NAME;
@@ -27,13 +24,11 @@
 import static com.google.common.base.Predicates.not;
 import static com.google.common.collect.Iterables.filter;
 import static com.google.common.collect.Iterables.getOnlyElement;
-import static com.google.common.collect.Sets.union;
 import static com.squareup.javapoet.MethodSpec.constructorBuilder;
 import static com.squareup.javapoet.MethodSpec.methodBuilder;
 import static com.squareup.javapoet.TypeSpec.classBuilder;
 import static java.util.stream.Collectors.joining;
 import static java.util.stream.Collectors.toList;
-import static java.util.stream.Collectors.toSet;
 import static javax.lang.model.element.Modifier.ABSTRACT;
 import static javax.lang.model.element.Modifier.FINAL;
 import static javax.lang.model.element.Modifier.PRIVATE;
@@ -46,11 +41,8 @@
 import static javax.tools.Diagnostic.Kind.ERROR;
 
 import com.google.auto.common.MoreElements;
-import com.google.auto.common.MoreTypes;
-import com.google.auto.common.Visibility;
 import com.google.auto.service.AutoService;
 import com.google.auto.value.extension.AutoValueExtension;
-import com.google.common.base.Equivalence.Wrapper;
 import com.google.common.collect.ImmutableList;
 import com.google.common.collect.ImmutableSet;
 import com.google.errorprone.annotations.FormatMethod;
@@ -64,19 +56,14 @@
 import com.squareup.javapoet.TypeName;
 import com.squareup.javapoet.TypeSpec;
 import com.squareup.javapoet.TypeVariableName;
-import java.lang.annotation.Inherited;
 import java.util.List;
 import java.util.Optional;
-import java.util.Set;
 import javax.annotation.processing.Messager;
 import javax.annotation.processing.ProcessingEnvironment;
 import javax.lang.model.SourceVersion;
 import javax.lang.model.element.AnnotationMirror;
-import javax.lang.model.element.AnnotationValue;
-import javax.lang.model.element.Element;
 import javax.lang.model.element.ExecutableElement;
 import javax.lang.model.element.Modifier;
-import javax.lang.model.element.QualifiedNameable;
 import javax.lang.model.element.TypeElement;
 import javax.lang.model.type.TypeMirror;
 import javax.lang.model.util.Elements;
@@ -92,11 +79,6 @@ public final class MemoizeExtension extends AutoValueExtension {
   private static final ImmutableSet<String> DO_NOT_PULL_DOWN_ANNOTATIONS =
       ImmutableSet.of(Override.class.getCanonicalName(), MEMOIZED_NAME);
 
-  // TODO(b/122509249): Move code copied from com.google.auto.value.processor to auto-common.
-  private static final String AUTO_VALUE_PACKAGE_NAME = "com.google.auto.value.";
-  private static final String AUTO_VALUE_NAME = AUTO_VALUE_PACKAGE_NAME + "AutoValue";
-  private static final String COPY_ANNOTATIONS_NAME = AUTO_VALUE_NAME + ".CopyAnnotations";
-
   // Maven is configured to shade (rewrite) com.google packages to prevent dependency conflicts.
   // Split up the package here with a call to concat to prevent Maven from finding and rewriting it,
   // so that this will be able to find the LazyInit annotation if it's on the classpath.
@@ -156,7 +138,10 @@ String generate() {
       TypeSpec.Builder generated =
           classBuilder(className)
               .superclass(superType())
-              .addAnnotations(copiedClassAnnotations(context.autoValueClass()))
+              .addAnnotations(
+                  context.classAnnotationsToCopy(context.autoValueClass()).stream()
+                      .map(AnnotationSpec::get)
+                      .collect(toImmutableList()))
               .addTypeVariables(annotatedTypeVariableNames())
               .addModifiers(isFinal ? FINAL : ABSTRACT)
               .addMethod(constructor());
@@ -252,146 +237,6 @@ private MethodSpec equalsWithHashCodeCheck() {
           .build();
     }
 
-    // LINT.IfChange
-    /**
-     * True if the given class name is in the com.google.auto.value package or a subpackage. False
-     * if the class name contains {@code Test}, since many AutoValue tests under
-     * com.google.auto.value define their own annotations.
-     */
-    // TODO(b/122509249): Move code copied from com.google.auto.value.processor to auto-common.
-    private boolean isInAutoValuePackage(String className) {
-      return className.startsWith(AUTO_VALUE_PACKAGE_NAME) && !className.contains("Test");
-    }
-
-    /**
-     * Returns the fully-qualified name of an annotation-mirror, e.g.
-     * "com.google.auto.value.AutoValue".
-     */
-    // TODO(b/122509249): Move code copied from com.google.auto.value.processor to auto-common.
-    private static String getAnnotationFqName(AnnotationMirror annotation) {
-      return ((QualifiedNameable) annotation.getAnnotationType().asElement())
-          .getQualifiedName()
-          .toString();
-    }
-
-    // TODO(b/122509249): Move code copied from com.google.auto.value.processor to auto-common.
-    private boolean annotationVisibleFrom(AnnotationMirror annotation, Element from) {
-      Element annotationElement = annotation.getAnnotationType().asElement();
-      Visibility visibility = Visibility.effectiveVisibilityOfElement(annotationElement);
-      switch (visibility) {
-        case PUBLIC:
-          return true;
-        case PROTECTED:
-          // If the annotation is protected, it must be inside another class, call it C. If our
-          // @AutoValue class is Foo then, for the annotation to be visible, either Foo must be in
-          // the same package as C or Foo must be a subclass of C. If the annotation is visible from
-          // Foo then it is also visible from our generated subclass AutoValue_Foo.
-          // The protected case only applies to method annotations. An annotation on the
-          // AutoValue_Foo class itself can't be protected, even if AutoValue_Foo ultimately
-          // inherits from the class that defines the annotation. The JLS says "Access is permitted
-          // only within the body of a subclass":
-          // https://docs.oracle.com/javase/specs/jls/se8/html/jls-6.html#jls-6.6.2.1
-          // AutoValue_Foo is a top-level class, so an annotation on it cannot be in the body of a
-          // subclass of anything.
-          return getPackage(annotationElement).equals(getPackage(from))
-              || types.isSubtype(from.asType(), annotationElement.getEnclosingElement().asType());
-        case DEFAULT:
-          return getPackage(annotationElement).equals(getPackage(from));
-        default:
-          return false;
-      }
-    }
-
-    /** Implements the semantics of {@code AutoValue.CopyAnnotations}; see its javadoc. */
-    // TODO(b/122509249): Move code copied from com.google.auto.value.processor to auto-common.
-    private ImmutableList<AnnotationMirror> annotationsToCopy(
-        Element autoValueType, Element typeOrMethod, Set<String> excludedAnnotations) {
-      ImmutableList.Builder<AnnotationMirror> result = ImmutableList.builder();
-      for (AnnotationMirror annotation : typeOrMethod.getAnnotationMirrors()) {
-        String annotationFqName = getAnnotationFqName(annotation);
-        // To be included, the annotation should not be in com.google.auto.value,
-        // and it should not be in the excludedAnnotations set.
-        if (!isInAutoValuePackage(annotationFqName)
-            && !excludedAnnotations.contains(annotationFqName)
-            && annotationVisibleFrom(annotation, autoValueType)) {
-          result.add(annotation);
-        }
-      }
-
-      return result.build();
-    }
-
-    /** Implements the semantics of {@code AutoValue.CopyAnnotations}; see its javadoc. */
-    // TODO(b/122509249): Move code copied from com.google.auto.value.processor to auto-common.
-    private ImmutableList<AnnotationSpec> copyAnnotations(
-        Element autoValueType, Element typeOrMethod, Set<String> excludedAnnotations) {
-      ImmutableList<AnnotationMirror> annotationsToCopy =
-          annotationsToCopy(autoValueType, typeOrMethod, excludedAnnotations);
-      return annotationsToCopy.stream().map(AnnotationSpec::get).collect(toImmutableList());
-    }
-
-    // TODO(b/122509249): Move code copied from com.google.auto.value.processor to auto-common.
-    private static boolean hasAnnotationMirror(Element element, String annotationName) {
-      return getAnnotationMirror(element, annotationName).isPresent();
-    }
-
-    /**
-     * Returns the contents of the {@code AutoValue.CopyAnnotations.exclude} element, as a set of
-     * {@code TypeMirror} where each type is an annotation type.
-     */
-    // TODO(b/122509249): Move code copied from com.google.auto.value.processor to auto-common.
-    private ImmutableSet<TypeMirror> getExcludedAnnotationTypes(Element element) {
-      Optional<AnnotationMirror> maybeAnnotation =
-          getAnnotationMirror(element, COPY_ANNOTATIONS_NAME);
-      if (!maybeAnnotation.isPresent()) {
-        return ImmutableSet.of();
-      }
-
-      @SuppressWarnings("unchecked")
-      List<AnnotationValue> excludedClasses =
-          (List<AnnotationValue>) getAnnotationValue(maybeAnnotation.get(), "exclude").getValue();
-      return excludedClasses.stream()
-          .map(
-              annotationValue ->
-                  MoreTypes.equivalence().wrap((TypeMirror) annotationValue.getValue()))
-          // TODO(b/122509249): Move TypeMirrorSet to common package instead of doing this.
-          .distinct()
-          .map(Wrapper::get)
-          .collect(toImmutableSet());
-    }
-
-    /**
-     * Returns the contents of the {@code AutoValue.CopyAnnotations.exclude} element, as a set of
-     * strings that are fully-qualified class names.
-     */
-    // TODO(b/122509249): Move code copied from com.google.auto.value.processor to auto-common.
-    private Set<String> getExcludedAnnotationClassNames(Element element) {
-      return getExcludedAnnotationTypes(element).stream()
-          .map(MoreTypes::asTypeElement)
-          .map(typeElement -> typeElement.getQualifiedName().toString())
-          .collect(toSet());
-    }
-
-    // TODO(b/122509249): Move code copied from com.google.auto.value.processor to auto-common.
-    private static Set<String> getAnnotationsMarkedWithInherited(Element element) {
-      return element.getAnnotationMirrors().stream()
-          .filter(a -> isAnnotationPresent(a.getAnnotationType().asElement(), Inherited.class))
-          .map(Generator::getAnnotationFqName)
-          .collect(toSet());
-    }
-
-    private ImmutableList<AnnotationSpec> copiedClassAnnotations(TypeElement type) {
-      // Only copy annotations from a class if it has @AutoValue.CopyAnnotations.
-      if (hasAnnotationMirror(type, COPY_ANNOTATIONS_NAME)) {
-        Set<String> excludedAnnotations =
-            union(getExcludedAnnotationClassNames(type), getAnnotationsMarkedWithInherited(type));
-
-        return copyAnnotations(type, type, excludedAnnotations);
-      } else {
-        return ImmutableList.of();
-      }
-    }
-
     /**
      * Determines the required fields and overriding method for a {@link
      * com.google.auto.value.extension.memoized.Memoized @Memoized} method.
@@ -416,7 +261,7 @@ private final class MethodOverrider {
                 .addExceptions(
                     method.getThrownTypes().stream().map(TypeName::get).collect(toList()))
                 .addModifiers(filter(method.getModifiers(), not(equalTo(ABSTRACT))));
-        for (AnnotationMirror annotation : method.getAnnotationMirrors()) {
+        for (AnnotationMirror annotation : context.methodAnnotationsToCopy(method)) {
           AnnotationSpec annotationSpec = AnnotationSpec.get(annotation);
           if (pullDownMethodAnnotation(annotation)) {
             override.addAnnotation(annotationSpec);