Pull AliasOfPropagatedDataMetadata into its own source file.

RELNOTES=N/A
PiperOrigin-RevId: 366859328

6 files changed, 128 insertions, 76 deletions

diff --git a/java/dagger/hilt/processor/internal/ClassNames.java b/java/dagger/hilt/processor/internal/ClassNames.java
index 2fa090083..ac6b34623 100644
--- a/java/dagger/hilt/processor/internal/ClassNames.java
+++ b/java/dagger/hilt/processor/internal/ClassNames.java
@@ -86,6 +86,8 @@ public final class ClassNames {
   public static final ClassName ALIAS_OF = get("dagger.hilt.migration", "AliasOf");
   public static final ClassName ALIAS_OF_PROPAGATED_DATA =
       get("dagger.hilt.internal.aliasof", "AliasOfPropagatedData");
+  public static final String ALIAS_OF_PROPAGATED_DATA_PACKAGE =
+      "dagger.hilt.processor.internal.aliasof.codegen";
 
   public static final ClassName GENERATES_ROOT_INPUT = get("dagger.hilt", "GeneratesRootInput");
   public static final ClassName GENERATES_ROOT_INPUT_PROPAGATED_DATA =
diff --git a/java/dagger/hilt/processor/internal/aliasof/AliasOfPropagatedDataGenerator.java b/java/dagger/hilt/processor/internal/aliasof/AliasOfPropagatedDataGenerator.java
index 75c4c15ac..2ccb5cfbd 100644
--- a/java/dagger/hilt/processor/internal/aliasof/AliasOfPropagatedDataGenerator.java
+++ b/java/dagger/hilt/processor/internal/aliasof/AliasOfPropagatedDataGenerator.java
@@ -52,7 +52,7 @@ final class AliasOfPropagatedDataGenerator {
 
     Processors.addGeneratedAnnotation(generator, processingEnv, getClass());
 
-    JavaFile.builder(AliasOfs.AGGREGATING_PACKAGE, generator.build())
+    JavaFile.builder(ClassNames.ALIAS_OF_PROPAGATED_DATA_PACKAGE, generator.build())
         .build()
         .writeTo(processingEnv.getFiler());
   }
diff --git a/java/dagger/hilt/processor/internal/aliasof/AliasOfPropagatedDataMetadata.java b/java/dagger/hilt/processor/internal/aliasof/AliasOfPropagatedDataMetadata.java
new file mode 100644
index 000000000..1ba41d57b
--- /dev/null
+++ b/java/dagger/hilt/processor/internal/aliasof/AliasOfPropagatedDataMetadata.java
@@ -0,0 +1,97 @@
+/*
+ * Copyright (C) 2021 The Dagger Authors.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package dagger.hilt.processor.internal.aliasof;
+
+import static com.google.auto.common.MoreElements.asType;
+import static com.google.auto.common.MoreElements.isType;
+
+import com.google.auto.value.AutoValue;
+import com.google.common.collect.ImmutableSet;
+import dagger.hilt.processor.internal.ClassNames;
+import dagger.hilt.processor.internal.ProcessorErrors;
+import dagger.hilt.processor.internal.Processors;
+import javax.lang.model.element.AnnotationMirror;
+import javax.lang.model.element.Element;
+import javax.lang.model.element.PackageElement;
+import javax.lang.model.element.TypeElement;
+import javax.lang.model.util.Elements;
+
+/**
+ * A class that represents the values stored in an {@link
+ * dagger.hilt.internal.aliasof.AliasOfPropagatedData} annotation.
+ */
+@AutoValue
+abstract class AliasOfPropagatedDataMetadata {
+
+  abstract TypeElement defineComponentScopeElement();
+
+  abstract TypeElement aliasElement();
+
+  static ImmutableSet<AliasOfPropagatedDataMetadata> from(Elements elements) {
+    PackageElement packageElement =
+        elements.getPackageElement(ClassNames.ALIAS_OF_PROPAGATED_DATA_PACKAGE);
+
+    if (packageElement == null) {
+      return ImmutableSet.of();
+    }
+
+    ImmutableSet<Element> aggregatedElements =
+        ImmutableSet.copyOf(packageElement.getEnclosedElements());
+
+    ProcessorErrors.checkState(
+        !aggregatedElements.isEmpty(),
+        packageElement,
+        "No dependencies found. Did you remove code in package %s?",
+        ClassNames.ALIAS_OF_PROPAGATED_DATA_PACKAGE);
+
+    ImmutableSet.Builder<AliasOfPropagatedDataMetadata> builder = ImmutableSet.builder();
+    for (Element element : aggregatedElements) {
+      ProcessorErrors.checkState(
+          isType(element),
+          element,
+          "Only types may be in package %s. Did you add custom code in the package?",
+          ClassNames.ALIAS_OF_PROPAGATED_DATA_PACKAGE);
+
+      builder.add(create(asType(element), elements));
+    }
+    return builder.build();
+  }
+
+  private static AliasOfPropagatedDataMetadata create(TypeElement element, Elements elements) {
+    AnnotationMirror annotationMirror =
+        Processors.getAnnotationMirror(element, ClassNames.ALIAS_OF_PROPAGATED_DATA);
+
+    ProcessorErrors.checkState(
+        annotationMirror != null,
+        element,
+        "Classes in package %s must be annotated with @%s: %s."
+            + " Found: %s. Files in this package are generated, did you add custom code in the"
+            + " package? ",
+        ClassNames.ALIAS_OF_PROPAGATED_DATA_PACKAGE,
+        ClassNames.ALIAS_OF_PROPAGATED_DATA,
+        element.getSimpleName(),
+        element.getAnnotationMirrors());
+
+    TypeElement defineComponentScopeElement =
+        Processors.getAnnotationClassValue(elements, annotationMirror, "defineComponentScope");
+
+    TypeElement aliasElement =
+        Processors.getAnnotationClassValue(elements, annotationMirror, "alias");
+
+    return new AutoValue_AliasOfPropagatedDataMetadata(defineComponentScopeElement, aliasElement);
+  }
+}
diff --git a/java/dagger/hilt/processor/internal/aliasof/AliasOfs.java b/java/dagger/hilt/processor/internal/aliasof/AliasOfs.java
index 930a72e27..18951bdf9 100644
--- a/java/dagger/hilt/processor/internal/aliasof/AliasOfs.java
+++ b/java/dagger/hilt/processor/internal/aliasof/AliasOfs.java
@@ -16,23 +16,11 @@
 
 package dagger.hilt.processor.internal.aliasof;
 
-import static com.google.common.base.Suppliers.memoize;
 
-import com.google.common.base.Preconditions;
-import com.google.common.base.Supplier;
-import com.google.common.collect.ImmutableMultimap;
 import com.google.common.collect.ImmutableSet;
+import com.google.common.collect.ImmutableSetMultimap;
 import com.squareup.javapoet.ClassName;
-import dagger.hilt.processor.internal.ClassNames;
 import dagger.hilt.processor.internal.ProcessorErrors;
-import dagger.hilt.processor.internal.Processors;
-import java.util.List;
-import javax.annotation.processing.ProcessingEnvironment;
-import javax.lang.model.element.AnnotationMirror;
-import javax.lang.model.element.Element;
-import javax.lang.model.element.ElementKind;
-import javax.lang.model.element.PackageElement;
-import javax.lang.model.element.TypeElement;
 import javax.lang.model.util.Elements;
 
 /**
@@ -40,69 +28,33 @@ import javax.lang.model.util.Elements;
  * to scopes they are alias of.
  */
 public final class AliasOfs {
-  static final String AGGREGATING_PACKAGE = AliasOfs.class.getPackage().getName() + ".codegen";
+  public static AliasOfs create(Elements elements, ImmutableSet<ClassName> defineComponentScopes) {
+    ImmutableSetMultimap.Builder<ClassName, ClassName> builder = ImmutableSetMultimap.builder();
+    AliasOfPropagatedDataMetadata.from(elements)
+        .forEach(
+            metadata -> {
+              ClassName defineComponentScopeName =
+                  ClassName.get(metadata.defineComponentScopeElement());
+              ClassName aliasScopeName = ClassName.get(metadata.aliasElement());
+              ProcessorErrors.checkState(
+                  defineComponentScopes.contains(defineComponentScopeName),
+                  metadata.aliasElement(),
+                  "The scope %s cannot be an alias for %s. You can only have aliases of a scope"
+                      + " defined directly on a @DefineComponent type.",
+                  aliasScopeName,
+                  defineComponentScopeName);
+              builder.put(defineComponentScopeName, aliasScopeName);
+            });
+    return new AliasOfs(builder.build());
+  }
 
-  private final ProcessingEnvironment processingEnvironment;
-  private final ImmutableSet<ClassName> defineComponentScopes;
-  private final Supplier<ImmutableMultimap<ClassName, ClassName>> aliases =
-      memoize(() -> getAliases());
+  private final ImmutableSetMultimap<ClassName, ClassName> defineComponentScopeToAliases;
 
-  public AliasOfs(
-      ProcessingEnvironment processingEnvironment, ImmutableSet<ClassName> defineComponentScopes) {
-    this.defineComponentScopes = defineComponentScopes;
-    this.processingEnvironment = processingEnvironment;
+  private AliasOfs(ImmutableSetMultimap<ClassName, ClassName> defineComponentScopeToAliases) {
+    this.defineComponentScopeToAliases = defineComponentScopeToAliases;
   }
 
   public ImmutableSet<ClassName> getAliasesFor(ClassName defineComponentScope) {
-    return ImmutableSet.copyOf(aliases.get().get(defineComponentScope));
-  }
-
-  private ImmutableMultimap<ClassName, ClassName> getAliases() {
-    Elements elements = processingEnvironment.getElementUtils();
-    PackageElement packageElement = elements.getPackageElement(AGGREGATING_PACKAGE);
-    if (packageElement == null) {
-      return ImmutableMultimap.of();
-    }
-    List<? extends Element> scopeAliasElements = packageElement.getEnclosedElements();
-    Preconditions.checkState(
-        !scopeAliasElements.isEmpty(), "No scope aliases Found in package %s.", packageElement);
-
-    ImmutableMultimap.Builder<ClassName, ClassName> builder = ImmutableMultimap.builder();
-    for (Element element : scopeAliasElements) {
-      ProcessorErrors.checkState(
-          element.getKind() == ElementKind.CLASS,
-          element,
-          "Only classes may be in package %s. Did you add custom code in the package?",
-          packageElement);
-
-      AnnotationMirror annotationMirror =
-          Processors.getAnnotationMirror(element, ClassNames.ALIAS_OF_PROPAGATED_DATA);
-
-      ProcessorErrors.checkState(
-          annotationMirror != null,
-          element,
-          "Classes in package %s must be annotated with @%s: %s."
-              + " Found: %s. Files in this package are generated, did you add custom code in the"
-              + " package? ",
-          packageElement,
-          ClassNames.ALIAS_OF_PROPAGATED_DATA,
-          element.getSimpleName(),
-          element.getAnnotationMirrors());
-
-      TypeElement defineComponentScope =
-          Processors.getAnnotationClassValue(elements, annotationMirror, "defineComponentScope");
-      TypeElement alias = Processors.getAnnotationClassValue(elements, annotationMirror, "alias");
-
-      Preconditions.checkState(
-          defineComponentScopes.contains(ClassName.get(defineComponentScope)),
-          "The scope %s cannot be an alias for %s. You can only have aliases of a scope defined"
-              + " directly on a @DefineComponent type.",
-          ClassName.get(alias),
-          ClassName.get(defineComponentScope));
-
-      builder.put(ClassName.get(defineComponentScope), ClassName.get(alias));
-    }
-
-    return builder.build();
+    return defineComponentScopeToAliases.get(defineComponentScope);
   }
 }
diff --git a/java/dagger/hilt/processor/internal/aliasof/BUILD b/java/dagger/hilt/processor/internal/aliasof/BUILD
index d3f90f2fa..9a29a8ed8 100644
--- a/java/dagger/hilt/processor/internal/aliasof/BUILD
+++ b/java/dagger/hilt/processor/internal/aliasof/BUILD
@@ -31,7 +31,6 @@ java_library(
         "AliasOfPropagatedDataGenerator.java",
     ],
     deps = [
-        ":alias_ofs",
         "//java/dagger/hilt/processor/internal:base_processor",
         "//java/dagger/hilt/processor/internal:classnames",
         "//java/dagger/hilt/processor/internal:processor_errors",
@@ -46,15 +45,17 @@ java_library(
 java_library(
     name = "alias_ofs",
     srcs = [
+        "AliasOfPropagatedDataMetadata.java",
         "AliasOfs.java",
     ],
     deps = [
         "//java/dagger/hilt/processor/internal:classnames",
         "//java/dagger/hilt/processor/internal:processor_errors",
         "//java/dagger/hilt/processor/internal:processors",
-        "//java/dagger/internal/guava:base",
         "//java/dagger/internal/guava:collect",
+        "@google_bazel_common//third_party/java/auto:value",
         "@google_bazel_common//third_party/java/javapoet",
+        "@maven//:com_google_auto_auto_common",
     ],
 )
 
diff --git a/java/dagger/hilt/processor/internal/root/RootMetadata.java b/java/dagger/hilt/processor/internal/root/RootMetadata.java
index e3ace8ef0..76d1d1495 100644
--- a/java/dagger/hilt/processor/internal/root/RootMetadata.java
+++ b/java/dagger/hilt/processor/internal/root/RootMetadata.java
@@ -242,7 +242,7 @@ public final class RootMetadata {
             .flatMap(descriptor -> descriptor.scopes().stream())
             .collect(toImmutableSet());
 
-    AliasOfs aliasOfs = new AliasOfs(env, defineComponentScopes);
+    AliasOfs aliasOfs = AliasOfs.create(env.getElementUtils(), defineComponentScopes);
 
     for (ComponentDescriptor componentDescriptor : componentTree.getComponentDescriptors()) {
       for (ClassName scope : componentDescriptor.scopes()) {