Attempt #4 Adds FakeAutoCodecProcessor to bazel-distfile.

Change-Id: Ie8dd0aa0ed6234fc3fd2e337fd50f9f7d5c7d2c1
PiperOrigin-RevId: 179607524

5 files changed, 204 insertions, 24 deletions

diff --git a/BUILD b/BUILD
index f21bbad90c..32b9c62031 100644
--- a/BUILD
+++ b/BUILD
@@ -83,6 +83,7 @@ genrule(
     srcs = [
         ":bazel-srcs",
         "//src:derived_java_srcs",
+        "//src/main/java/com/google/devtools/build/lib/skyframe/serialization/autocodec:bootstrap_autocodec.tar",
     ],
     outs = ["bazel-distfile.zip"],
     cmd = "$(location :combine_distfiles) $@ $(SRCS)",
@@ -96,6 +97,7 @@ genrule(
     srcs = [
         ":bazel-srcs",
         "//src:derived_java_srcs",
+        "//src/main/java/com/google/devtools/build/lib/skyframe/serialization/autocodec:bootstrap_autocodec.tar",
     ],
     outs = ["bazel-distfile.tar"],
     cmd = "$(location :combine_distfiles_to_tar.sh) $@ $(SRCS)",
diff --git a/src/main/java/com/google/devtools/build/lib/skyframe/serialization/autocodec/AutoCodecProcessor.java b/src/main/java/com/google/devtools/build/lib/skyframe/serialization/autocodec/AutoCodecProcessor.java
index 29df3cb46e..ed54d58508 100644
--- a/src/main/java/com/google/devtools/build/lib/skyframe/serialization/autocodec/AutoCodecProcessor.java
+++ b/src/main/java/com/google/devtools/build/lib/skyframe/serialization/autocodec/AutoCodecProcessor.java
@@ -15,7 +15,6 @@
 package com.google.devtools.build.lib.skyframe.serialization.autocodec;
 
 import com.google.auto.service.AutoService;
-import com.google.common.collect.ImmutableList;
 import com.google.common.collect.ImmutableSet;
 import com.google.common.collect.ImmutableSortedSet;
 import com.google.devtools.build.lib.skyframe.serialization.ObjectCodec;
@@ -55,10 +54,6 @@ import javax.tools.Diagnostic;
  */
 @AutoService(Processor.class)
 public class AutoCodecProcessor extends AbstractProcessor {
-  // Synthesized classes will be prefixed with AutoCodec_.
-  public static final String GENERATED_CLASS_NAME_PREFIX = "AutoCodec";
-  private static final Class<AutoCodec> ANNOTATION = AutoCodec.class;
-
   /**
    * Passing {@code --javacopt=-Aautocodec_print_generated} to {@code blaze build} tells AutoCodec
    * to print the generated code.
@@ -74,7 +69,7 @@ public class AutoCodecProcessor extends AbstractProcessor {
 
   @Override
   public Set<String> getSupportedAnnotationTypes() {
-    return ImmutableSet.of(ANNOTATION.getCanonicalName());
+    return ImmutableSet.of(AutoCodecUtil.ANNOTATION.getCanonicalName());
   }
 
   @Override
@@ -90,8 +85,8 @@ public class AutoCodecProcessor extends AbstractProcessor {
 
   @Override
   public boolean process(Set<? extends TypeElement> annotations, RoundEnvironment roundEnv) {
-    for (Element element : roundEnv.getElementsAnnotatedWith(ANNOTATION)) {
-      AutoCodec annotation = element.getAnnotation(ANNOTATION);
+    for (Element element : roundEnv.getElementsAnnotatedWith(AutoCodecUtil.ANNOTATION)) {
+      AutoCodec annotation = element.getAnnotation(AutoCodecUtil.ANNOTATION);
       switch (annotation.strategy()) {
         case CONSTRUCTOR:
           buildCodecUsingConstructor((TypeElement) element);
@@ -120,7 +115,7 @@ public class AutoCodecProcessor extends AbstractProcessor {
    */
   private void buildCodecUsingConstructor(TypeElement classElement) {
     TypeSpec.Builder codecClassBuilder =
-        TypeSpec.classBuilder(getCodecName(classElement))
+        TypeSpec.classBuilder(AutoCodecUtil.getCodecName(classElement))
             .superclass(TypeName.get(classElement.asType()));
 
     TypeElement encodedType = getEncodedType(classElement);
@@ -166,21 +161,6 @@ public class AutoCodecProcessor extends AbstractProcessor {
     return "get" + name.substring(0, 1).toUpperCase() + name.substring(1) + "()";
   }
 
-  /**
-   * Name of the generated codec class.
-   *
-   * <p>For {@code Foo.Bar.Codec} this is {@code AutoCodec_Foo_Bar_Codec}.
-   */
-  private static String getCodecName(Element element) {
-    ImmutableList.Builder<String> classNamesBuilder = new ImmutableList.Builder<>();
-    do {
-      classNamesBuilder.add(element.getSimpleName().toString());
-      element = element.getEnclosingElement();
-    } while (element instanceof TypeElement);
-    classNamesBuilder.add(GENERATED_CLASS_NAME_PREFIX);
-    return classNamesBuilder.build().reverse().stream().collect(Collectors.joining("_"));
-  }
-
   private void addSerializeMethodUsingConstructor(
       TypeSpec.Builder codecClassBuilder,
       TypeElement encodedType,
diff --git a/src/main/java/com/google/devtools/build/lib/skyframe/serialization/autocodec/AutoCodecUtil.java b/src/main/java/com/google/devtools/build/lib/skyframe/serialization/autocodec/AutoCodecUtil.java
new file mode 100644
index 0000000000..a4b39c8ee1
--- /dev/null
+++ b/src/main/java/com/google/devtools/build/lib/skyframe/serialization/autocodec/AutoCodecUtil.java
@@ -0,0 +1,42 @@
+// Copyright 2017 The Bazel Authors. All rights reserved.
+//
+// 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 com.google.devtools.build.lib.skyframe.serialization.autocodec;
+
+import com.google.common.collect.ImmutableList;
+import java.util.stream.Collectors;
+import javax.lang.model.element.Element;
+import javax.lang.model.element.TypeElement;
+
+/** Static utilities for AutoCodec processors. */
+class AutoCodecUtil {
+  // Synthesized classes will have `_AutoCodec` suffix added.
+  public static final String GENERATED_CLASS_NAME_SUFFIX = "AutoCodec";
+  static final Class<AutoCodec> ANNOTATION = AutoCodec.class;
+
+  /**
+   * Name of the generated codec class.
+   *
+   * <p>For {@code Foo.Bar} this is {@code Foo_Bar_AutoCodec}.
+   */
+  static String getCodecName(Element element) {
+    ImmutableList.Builder<String> classNamesBuilder = new ImmutableList.Builder<>();
+    classNamesBuilder.add(GENERATED_CLASS_NAME_SUFFIX);
+    do {
+      classNamesBuilder.add(element.getSimpleName().toString());
+      element = element.getEnclosingElement();
+    } while (element instanceof TypeElement);
+    return classNamesBuilder.build().reverse().stream().collect(Collectors.joining("_"));
+  }
+}
diff --git a/src/main/java/com/google/devtools/build/lib/skyframe/serialization/autocodec/BUILD b/src/main/java/com/google/devtools/build/lib/skyframe/serialization/autocodec/BUILD
index 5807597e65..193570ebb4 100644
--- a/src/main/java/com/google/devtools/build/lib/skyframe/serialization/autocodec/BUILD
+++ b/src/main/java/com/google/devtools/build/lib/skyframe/serialization/autocodec/BUILD
@@ -35,6 +35,7 @@ java_library(
     srcs = ["AutoCodecProcessor.java"],
     deps = [
         ":autocodec-annotation",
+        ":autocodec-util",
         "//src/main/java/com/google/devtools/build/lib/skyframe/serialization",
         "//third_party:auto_service",
         "//third_party:guava",
@@ -42,3 +43,44 @@ java_library(
         "//third_party/protobuf:protobuf_java",
     ],
 )
+
+# Code shared between autocodec-processor and fake-autocodec-processor.
+java_library(
+    name = "autocodec-util",
+    srcs = ["AutoCodecUtil.java"],
+    deps = [
+        ":autocodec-annotation",
+        "//third_party:guava",
+    ],
+)
+
+# This is a fake implementation for bootstrapping. It must *not* be used in production.
+java_library(
+    name = "fake-autocodec-processor",
+    srcs = ["FakeAutoCodecProcessor.java"],
+    deps = [
+        ":autocodec-util",
+        "//src/main/java/com/google/devtools/build/lib/skyframe/serialization",
+        "//third_party:auto_service",
+        "//third_party:guava",
+        "//third_party/java/javapoet",
+        "//third_party/protobuf:protobuf_java",
+    ],
+)
+
+load("//tools/build_defs/pkg:pkg.bzl", "pkg_tar")
+
+# .tar archive of dependencies used for bootstrapping.
+pkg_tar(
+    name = "bootstrap_autocodec",
+    # The .jar files are created within the .tar file under third_party/bazel_bootstrap so that
+    # they will appear there in bazel-distfile, which in turn makes them visible for bootstrapping
+    # from the LIBRARY_JARS rule of bazel/scripts/bootstrap/compile.sh.
+    files = {
+        ":libautocodec-annotation.jar": "third_party/bazel_bootstrap/libautocodec-annotation.jar",
+        ":libautocodec-util.jar": "third_party/bazel_bootstrap/libautocodec-util.jar",
+        ":libfake-autocodec-processor.jar": "third_party/bazel_bootstrap/libfake-autocodec-processor.jar",
+        "//src/main/java/com/google/devtools/build/lib/skyframe/serialization:libserialization.jar": "third_party/bazel_bootstrap/libserialization.jar",
+    },
+    visibility = ["//visibility:public"],
+)
diff --git a/src/main/java/com/google/devtools/build/lib/skyframe/serialization/autocodec/FakeAutoCodecProcessor.java b/src/main/java/com/google/devtools/build/lib/skyframe/serialization/autocodec/FakeAutoCodecProcessor.java
new file mode 100644
index 0000000000..bdd8462a3b
--- /dev/null
+++ b/src/main/java/com/google/devtools/build/lib/skyframe/serialization/autocodec/FakeAutoCodecProcessor.java
@@ -0,0 +1,114 @@
+// Copyright 2017 The Bazel Authors. All rights reserved.
+//
+// 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 com.google.devtools.build.lib.skyframe.serialization.autocodec;
+
+import com.google.auto.service.AutoService;
+import com.google.common.collect.ImmutableSet;
+import com.google.devtools.build.lib.skyframe.serialization.ObjectCodec;
+import com.google.protobuf.CodedInputStream;
+import com.google.protobuf.CodedOutputStream;
+import com.squareup.javapoet.ClassName;
+import com.squareup.javapoet.JavaFile;
+import com.squareup.javapoet.MethodSpec;
+import com.squareup.javapoet.ParameterizedTypeName;
+import com.squareup.javapoet.TypeName;
+import com.squareup.javapoet.TypeSpec;
+import java.io.IOException;
+import java.util.Set;
+import javax.annotation.processing.AbstractProcessor;
+import javax.annotation.processing.ProcessingEnvironment;
+import javax.annotation.processing.Processor;
+import javax.annotation.processing.RoundEnvironment;
+import javax.lang.model.SourceVersion;
+import javax.lang.model.element.Element;
+import javax.lang.model.element.Modifier;
+import javax.lang.model.element.TypeElement;
+import javax.tools.Diagnostic;
+
+/**
+ * A fake annotation processor for bootstrapping.
+ *
+ * <p>When bootstrapping, annotation processors inside the Bazel source tree are not available which
+ * means that if there are dependencies on generated code, bootstrapping will fail. This processor
+ * generates stub code to pass the initial boostrapping phase.
+ */
+@AutoService(Processor.class)
+public class FakeAutoCodecProcessor extends AbstractProcessor {
+  private ProcessingEnvironment env; // Captured from `init` method.
+
+  @Override
+  public Set<String> getSupportedAnnotationTypes() {
+    return ImmutableSet.of(AutoCodecUtil.ANNOTATION.getCanonicalName());
+  }
+
+  @Override
+  public SourceVersion getSupportedSourceVersion() {
+    return SourceVersion.latestSupported(); // Supports all versions of Java.
+  }
+
+  @Override
+  public synchronized void init(ProcessingEnvironment processingEnv) {
+    super.init(processingEnv);
+    this.env = processingEnv;
+  }
+
+  @Override
+  public boolean process(Set<? extends TypeElement> annotations, RoundEnvironment roundEnv) {
+    for (Element element : roundEnv.getElementsAnnotatedWith(AutoCodecUtil.ANNOTATION)) {
+      TypeElement encodedType = (TypeElement) element;
+      TypeSpec.Builder codecClassBuilder =
+          TypeSpec.classBuilder(AutoCodecUtil.getCodecName(encodedType))
+              .addSuperinterface(
+                  ParameterizedTypeName.get(
+                      ClassName.get(ObjectCodec.class), TypeName.get(encodedType.asType())));
+      codecClassBuilder.addMethod(
+          MethodSpec.methodBuilder("getEncodedClass")
+              .addModifiers(Modifier.PUBLIC)
+              .addAnnotation(Override.class)
+              .returns(
+                  ParameterizedTypeName.get(
+                      ClassName.get(Class.class), TypeName.get(encodedType.asType())))
+              .addStatement("throw new RuntimeException(\"Shouldn't be called.\")")
+              .build());
+      codecClassBuilder.addMethod(
+          MethodSpec.methodBuilder("serialize")
+              .addModifiers(Modifier.PUBLIC)
+              .addParameter(TypeName.get(encodedType.asType()), "input")
+              .addParameter(CodedOutputStream.class, "codedOut")
+              .addAnnotation(Override.class)
+              .addStatement("throw new RuntimeException(\"Shouldn't be called.\")")
+              .build());
+      codecClassBuilder.addMethod(
+          MethodSpec.methodBuilder("deserialize")
+              .addModifiers(Modifier.PUBLIC)
+              .returns(TypeName.get(encodedType.asType()))
+              .addParameter(CodedInputStream.class, "codedIn")
+              .addAnnotation(Override.class)
+              .addStatement("throw new RuntimeException(\"Shouldn't be called.\")")
+              .build());
+      String packageName =
+          env.getElementUtils().getPackageOf(encodedType).getQualifiedName().toString();
+      try {
+        JavaFile file = JavaFile.builder(packageName, codecClassBuilder.build()).build();
+        file.writeTo(env.getFiler());
+      } catch (IOException e) {
+        env.getMessager()
+            .printMessage(
+                Diagnostic.Kind.ERROR, "Failed to generate output file: " + e.getMessage());
+      }
+    }
+    return true;
+  }
+}