Create proto_toolchain rule

scripts/bootstrap/compile.sh

@@ -285,13 +285,18 @@ EOF
   link_file "${PWD}/tools/java/runfiles/Util.java" "${BAZEL_TOOLS_REPO}/tools/java/runfiles/Util.java"
   link_file "${PWD}/tools/java/runfiles/BUILD.tools" "${BAZEL_TOOLS_REPO}/tools/java/runfiles/BUILD"
 
+  # Create @bazel_tools/tools/proto/BUILD
+  mkdir -p ${BAZEL_TOOLS_REPO}/tools/proto
+  link_file "${PWD}/tools/proto/BUILD.tools" "${BAZEL_TOOLS_REPO}/tools/proto/BUILD"
+
   # Create @bazel_tools/tools/python/BUILD
   mkdir -p ${BAZEL_TOOLS_REPO}/tools/python
   link_file "${PWD}/tools/python/BUILD.tools" "${BAZEL_TOOLS_REPO}/tools/python/BUILD"
 
   # Create the rest of @bazel_tools//tools/...
   link_children "${PWD}" tools/cpp "${BAZEL_TOOLS_REPO}"
   mv -f ${BAZEL_TOOLS_REPO}/tools/cpp/BUILD.tools ${BAZEL_TOOLS_REPO}/tools/cpp/BUILD
+  link_children "${PWD}" tools/proto "${BAZEL_TOOLS_REPO}"
   link_children "${PWD}" tools/python "${BAZEL_TOOLS_REPO}"
   link_children "${PWD}" tools "${BAZEL_TOOLS_REPO}"
 

src/BUILD

@@ -161,8 +161,8 @@ rule_size_test(
     # WARNING: Only adjust the number in `expect` if you are intentionally
     # adding or removing embedded tools. Know that the more embedded tools there
     # are in Bazel, the bigger the binary becomes and the slower Bazel starts.
-    expect = 470,
-    margin = 5,  # percentage
+    expect = 500,
+    margin = 2,  # percentage
 )
 
 filegroup(

src/main/java/com/google/devtools/build/lib/bazel/rules/BazelRuleClassProvider.java

@@ -89,6 +89,7 @@
 import com.google.devtools.build.lib.rules.proto.ProtoConfiguration;
 import com.google.devtools.build.lib.rules.proto.ProtoInfo;
 import com.google.devtools.build.lib.rules.proto.ProtoLangToolchainRule;
+import com.google.devtools.build.lib.rules.proto.ProtoToolchainRule;
 import com.google.devtools.build.lib.rules.python.PyInfo;
 import com.google.devtools.build.lib.rules.python.PyRuleClasses.PySymlink;
 import com.google.devtools.build.lib.rules.python.PyRuntimeInfo;
@@ -254,6 +255,7 @@ public void init(ConfiguredRuleClassProvider.Builder builder) {
           builder.addConfigurationFragment(new ProtoConfiguration.Loader());
           builder.addRuleDefinition(new BazelProtoLibraryRule());
           builder.addRuleDefinition(new ProtoLangToolchainRule());
+          builder.addRuleDefinition(new ProtoToolchainRule());
 
           ProtoBootstrap bootstrap =
               new ProtoBootstrap(

src/main/java/com/google/devtools/build/lib/bazel/rules/BazelRulesModule.java

@@ -353,7 +353,7 @@ public static class GraveyardOptions extends OptionsBase {
         metadataTags = {OptionMetadataTag.DEPRECATED},
         help = "Deprecated no-op.")
     public String glibc;
-    
+
     @Deprecated
     @Option(
         name = "experimental_shortened_obj_file_path",
@@ -444,6 +444,8 @@ public void initializeRuleClasses(ConfiguredRuleClassProvider.Builder builder) {
     try {
       // Load auto-configuration files, it is made outside of the rule class provider so that it
       // will not be loaded for our Java tests.
+      builder.addWorkspaceFileSuffix(
+          ResourceFileLoader.loadResource(BazelRulesModule.class, "proto.WORKSPACE"));
       builder.addWorkspaceFileSuffix(
           ResourceFileLoader.loadResource(BazelRulesModule.class, "xcode_configure.WORKSPACE"));
       builder.addWorkspaceFileSuffix(

src/main/java/com/google/devtools/build/lib/bazel/rules/proto.WORKSPACE

@@ -0,0 +1,3 @@
+load("@bazel_tools//tools/proto:toolchain.bzl", "maybe_register_proto_toolchain")
+
+maybe_register_proto_toolchain()

src/main/java/com/google/devtools/build/lib/packages/StarlarkSemanticsOptions.java

@@ -629,6 +629,20 @@ public class StarlarkSemanticsOptions extends OptionsBase implements Serializabl
               + " modest cost in memory. The stack is visible in some forms of query output.")
   public boolean recordRuleInstantiationCallstack;
 
+  @Option(
+      name = "incompatible_provide_proto_toolchain_in_tools_workspace",
+      defaultValue = "false",
+      documentationCategory = OptionDocumentationCategory.STARLARK_SEMANTICS,
+      effectTags = {OptionEffectTag.LOADING_AND_ANALYSIS},
+      metadataTags = {
+        OptionMetadataTag.INCOMPATIBLE_CHANGE,
+        OptionMetadataTag.TRIGGERED_BY_ALL_INCOMPATIBLE_CHANGES
+      },
+      help =
+          "If set to true, the default proto_toolchain is no longer provided by Bazel and should "
+              + "be loaded from https://github.com/bazelbuild/rules_proto instead.")
+  public boolean incompatibleProvideProtoToolchainInToolsWorkspace;
+
   /**
    * An interner to reduce the number of StarlarkSemantics instances. A single Blaze instance should
    * never accumulate a large number of these and being able to shortcut on object identity makes a
@@ -688,6 +702,8 @@ public StarlarkSemantics toSkylarkSemantics() {
             .incompatibleLinkoptsToLinkLibs(incompatibleLinkoptsToLinkLibs)
             .maxComputationSteps(maxComputationSteps)
             .recordRuleInstantiationCallstack(recordRuleInstantiationCallstack)
+            .incompatibleProvideProtoToolchainInToolsWorkspace(
+                incompatibleProvideProtoToolchainInToolsWorkspace)
             .build();
     return INTERNER.intern(semantics);
   }

src/main/java/com/google/devtools/build/lib/rules/cpp/proto/CcProtoAspect.java

@@ -91,11 +91,13 @@ public abstract class CcProtoAspect extends NativeAspectClass implements Configu
   private final CppSemantics cppSemantics;
   private final LabelLateBoundDefault<?> ccToolchainAttrValue;
   private final Label ccToolchainType;
+  private final Label protoToolchainType;
 
   protected CcProtoAspect(AspectLegalCppSemantics cppSemantics, RuleDefinitionEnvironment env) {
     this.cppSemantics = cppSemantics;
     this.ccToolchainAttrValue = CppRuleClasses.ccToolchainAttribute(env);
     this.ccToolchainType = CppRuleClasses.ccToolchainTypeAttribute(env);
+    this.protoToolchainType = ProtoCommon.protoToolchainTypeAttribute(env);
   }
 
   @Override
@@ -124,7 +126,7 @@ public AspectDefinition getDefinition(AspectParameters aspectParameters) {
             .propagateAlongAttribute("deps")
             .requiresConfigurationFragments(CppConfiguration.class, ProtoConfiguration.class)
             .requireSkylarkProviders(ProtoInfo.PROVIDER.id())
-            .addRequiredToolchains(ccToolchainType)
+            .addRequiredToolchains(ccToolchainType, protoToolchainType)
             .add(
                 attr(PROTO_TOOLCHAIN_ATTR, LABEL)
                     .mandatoryNativeProviders(ImmutableList.of(ProtoLangToolchainProvider.class))

src/main/java/com/google/devtools/build/lib/rules/java/proto/JavaLiteProtoAspect.java

@@ -48,6 +48,7 @@
 import com.google.devtools.build.lib.rules.java.JavaSemantics;
 import com.google.devtools.build.lib.rules.java.JavaSkylarkApiProvider;
 import com.google.devtools.build.lib.rules.java.JavaSourceJarsProvider;
+import com.google.devtools.build.lib.rules.proto.ProtoCommon;
 import com.google.devtools.build.lib.rules.proto.ProtoCompileActionBuilder;
 import com.google.devtools.build.lib.rules.proto.ProtoCompileActionBuilder.Exports;
 import com.google.devtools.build.lib.rules.proto.ProtoCompileActionBuilder.Services;
@@ -71,6 +72,7 @@ public static LabelLateBoundDefault<?> getProtoToolchainLabel(String defaultValu
   private final String defaultProtoToolchainLabel;
   private final Label hostJdkAttribute;
   private final Label javaToolchainAttribute;
+  private final Label protoToolchainType;
 
   public JavaLiteProtoAspect(
       JavaSemantics javaSemantics,
@@ -80,6 +82,7 @@ public JavaLiteProtoAspect(
     this.defaultProtoToolchainLabel = defaultProtoToolchainLabel;
     this.hostJdkAttribute = JavaSemantics.hostJdkAttribute(env);
     this.javaToolchainAttribute = JavaSemantics.javaToolchainAttribute(env);
+    this.protoToolchainType = ProtoCommon.protoToolchainTypeAttribute(env);
   }
 
   @Override
@@ -110,6 +113,7 @@ public AspectDefinition getDefinition(AspectParameters aspectParameters) {
             .requiresConfigurationFragments(
                 JavaConfiguration.class, ProtoConfiguration.class, PlatformConfiguration.class)
             .requireSkylarkProviders(ProtoInfo.PROVIDER.id())
+            .addRequiredToolchains(protoToolchainType)
             .advertiseProvider(JavaProtoLibraryAspectProvider.class)
             .advertiseProvider(
                 ImmutableList.of(SkylarkProviderIdentifier.forKey(JavaInfo.PROVIDER.getKey())))

src/main/java/com/google/devtools/build/lib/rules/java/proto/JavaProtoAspect.java

@@ -48,6 +48,7 @@
 import com.google.devtools.build.lib.rules.java.JavaSemantics;
 import com.google.devtools.build.lib.rules.java.JavaSkylarkApiProvider;
 import com.google.devtools.build.lib.rules.java.JavaSourceJarsProvider;
+import com.google.devtools.build.lib.rules.proto.ProtoCommon;
 import com.google.devtools.build.lib.rules.proto.ProtoCompileActionBuilder;
 import com.google.devtools.build.lib.rules.proto.ProtoCompileActionBuilder.Exports;
 import com.google.devtools.build.lib.rules.proto.ProtoCompileActionBuilder.Services;
@@ -62,6 +63,7 @@ public class JavaProtoAspect extends NativeAspectClass implements ConfiguredAspe
 
   private final Label hostJdkAttribute;
   private final Label javaToolchainAttribute;
+  private final Label protoToolchainType;
 
   private static LabelLateBoundDefault<?> getSpeedProtoToolchainLabel(String defaultValue) {
     return LabelLateBoundDefault.fromTargetConfiguration(
@@ -86,6 +88,7 @@ protected JavaProtoAspect(
         Preconditions.checkNotNull(defaultSpeedProtoToolchainLabel);
     this.hostJdkAttribute = JavaSemantics.hostJdkAttribute(env);
     this.javaToolchainAttribute = JavaSemantics.javaToolchainAttribute(env);
+    this.protoToolchainType = ProtoCommon.protoToolchainTypeAttribute(env);
   }
 
   @Override
@@ -119,6 +122,7 @@ public AspectDefinition getDefinition(AspectParameters aspectParameters) {
             .requiresConfigurationFragments(
                 JavaConfiguration.class, ProtoConfiguration.class, PlatformConfiguration.class)
             .requireSkylarkProviders(ProtoInfo.PROVIDER.id())
+            .addRequiredToolchains(protoToolchainType)
             .advertiseProvider(JavaProtoLibraryAspectProvider.class)
             .advertiseProvider(
                 ImmutableList.of(SkylarkProviderIdentifier.forKey(JavaInfo.PROVIDER.getKey())))

src/main/java/com/google/devtools/build/lib/rules/proto/BUILD

@@ -25,6 +25,7 @@ java_library(
         "//src/main/java/com/google/devtools/build/lib:build-base",
         "//src/main/java/com/google/devtools/build/lib/actions",
         "//src/main/java/com/google/devtools/build/lib/actions:commandline_item",
+        "//src/main/java/com/google/devtools/build/lib/analysis/platform",
         "//src/main/java/com/google/devtools/build/lib/cmdline",
         "//src/main/java/com/google/devtools/build/lib/collect/nestedset",
         "//src/main/java/com/google/devtools/build/lib/concurrent",

src/main/java/com/google/devtools/build/lib/rules/proto/BazelProtoLibraryRule.java

@@ -49,6 +49,7 @@ public RuleClass build(RuleClass.Builder builder, final RuleDefinitionEnvironmen
 
     return builder
         .requiresConfigurationFragments(ProtoConfiguration.class)
+        .addRequiredToolchains(ProtoCommon.protoToolchainTypeAttribute(env))
         .setOutputToGenfiles()
         .add(
             attr(":proto_compiler", LABEL)

src/main/java/com/google/devtools/build/lib/rules/proto/ProtoCommon.java

@@ -22,6 +22,7 @@
 import com.google.devtools.build.lib.actions.Artifact;
 import com.google.devtools.build.lib.actions.ArtifactRoot;
 import com.google.devtools.build.lib.analysis.RuleContext;
+import com.google.devtools.build.lib.analysis.RuleDefinitionEnvironment;
 import com.google.devtools.build.lib.analysis.Runfiles;
 import com.google.devtools.build.lib.analysis.actions.SymlinkAction;
 import com.google.devtools.build.lib.analysis.config.CoreOptionConverters.StrictDepsMode;
@@ -53,6 +54,12 @@ private ProtoCommon() {
   public static final String PROTO_RULES_MIGRATION_LABEL =
       "__PROTO_RULES_MIGRATION_DO_NOT_USE_WILL_BREAK__";
 
+  private static final String TOOLCHAIN_TYPE_LABEL = "//tools/proto:toolchain_type";
+
+  public static Label protoToolchainTypeAttribute(RuleDefinitionEnvironment env) {
+    return env.getToolsLabel(TOOLCHAIN_TYPE_LABEL);
+  }
+
   /**
    * Gets the direct sources of a proto library. If protoSources is not empty, the value is just
    * protoSources. Otherwise, it's the combined sources of all direct dependencies of the given

src/main/java/com/google/devtools/build/lib/rules/proto/ProtoToolchain.java

@@ -0,0 +1,40 @@
+// Copyright 2020 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.rules.proto;
+
+import com.google.devtools.build.lib.actions.MutableActionGraph.ActionConflictException;
+import com.google.devtools.build.lib.analysis.ConfiguredTarget;
+import com.google.devtools.build.lib.analysis.RuleConfiguredTargetBuilder;
+import com.google.devtools.build.lib.analysis.RuleConfiguredTargetFactory;
+import com.google.devtools.build.lib.analysis.RuleContext;
+import com.google.devtools.build.lib.analysis.Runfiles;
+import com.google.devtools.build.lib.analysis.RunfilesProvider;
+
+/** The implementation of the <code>proto_toolchain</code> rule. */
+public class ProtoToolchain implements RuleConfiguredTargetFactory {
+  @Override
+  public ConfiguredTarget create(RuleContext ruleContext)
+      throws ActionConflictException, RuleErrorException, InterruptedException {
+    ProtoCommon.checkRuleHasValidMigrationTag(ruleContext);
+
+    ProtoToolchainInfo toolchain = new ProtoToolchainInfo();
+    RuleConfiguredTargetBuilder builder =
+        new RuleConfiguredTargetBuilder(ruleContext)
+            .addNativeDeclaredProvider(toolchain)
+            .addProvider(RunfilesProvider.class, RunfilesProvider.simple(Runfiles.EMPTY));
+
+    return builder.build();
+  }
+}

src/main/java/com/google/devtools/build/lib/rules/proto/ProtoToolchainInfo.java

@@ -0,0 +1,34 @@
+// Copyright 2020 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.rules.proto;
+
+import com.google.common.collect.ImmutableMap;
+import com.google.devtools.build.lib.analysis.platform.ToolchainInfo;
+import com.google.devtools.build.lib.concurrent.ThreadSafety.Immutable;
+import com.google.devtools.build.lib.skyframe.serialization.autocodec.AutoCodec;
+import com.google.devtools.build.lib.skylarkbuildapi.proto.ProtoToolchainInfoApi;
+import com.google.devtools.build.lib.syntax.Location;
+
+/**
+ * Information about the tools used by the <code>proto_*</code> and <code>LANG_proto_*</code> rules.
+ */
+@Immutable
+@AutoCodec
+public class ProtoToolchainInfo extends ToolchainInfo implements ProtoToolchainInfoApi {
+  @AutoCodec.Instantiator
+  public ProtoToolchainInfo() {
+    super(ImmutableMap.of(), Location.BUILTIN);
+  }
+}

src/main/java/com/google/devtools/build/lib/rules/proto/ProtoToolchainRule.java

@@ -0,0 +1,40 @@
+// Copyright 2020 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.rules.proto;
+
+import com.google.devtools.build.lib.analysis.BaseRuleClasses;
+import com.google.devtools.build.lib.analysis.RuleDefinition;
+import com.google.devtools.build.lib.analysis.RuleDefinitionEnvironment;
+import com.google.devtools.build.lib.packages.RuleClass;
+
+/** Rule definition of the <code>proto_toolchain</code> rule. */
+public class ProtoToolchainRule implements RuleDefinition {
+  @Override
+  public RuleClass build(RuleClass.Builder builder, final RuleDefinitionEnvironment env) {
+    return builder
+        .requiresConfigurationFragments(ProtoConfiguration.class)
+        .advertiseProvider(ProtoToolchainInfo.class)
+        .build();
+  }
+
+  @Override
+  public Metadata getMetadata() {
+    return RuleDefinition.Metadata.builder()
+        .name("proto_toolchain")
+        .ancestors(BaseRuleClasses.BaseRule.class)
+        .factoryClass(ProtoToolchain.class)
+        .build();
+  }
+}

src/main/java/com/google/devtools/build/lib/skylarkbuildapi/proto/BUILD

@@ -23,6 +23,7 @@ java_library(
         "//src/main/java/com/google/devtools/build/lib:syntax",
         "//src/main/java/com/google/devtools/build/lib/skylarkbuildapi",
         "//src/main/java/com/google/devtools/build/lib/skylarkbuildapi/core",
+        "//src/main/java/com/google/devtools/build/lib/skylarkbuildapi/platform",
         "//src/main/java/com/google/devtools/build/lib/skylarkinterface",
         "//third_party:guava",
     ],

src/main/java/com/google/devtools/build/lib/skylarkbuildapi/proto/ProtoCommonApi.java

@@ -14,7 +14,9 @@
 
 package com.google.devtools.build.lib.skylarkbuildapi.proto;
 
+import com.google.devtools.build.lib.skylarkinterface.SkylarkCallable;
 import com.google.devtools.build.lib.skylarkinterface.SkylarkModule;
+import com.google.devtools.build.lib.syntax.StarlarkSemantics.FlagIdentifier;
 import com.google.devtools.build.lib.syntax.StarlarkValue;
 
 /**
@@ -31,4 +33,15 @@
             + "to load this symbol from <a href=\"https://github.com/bazelbuild/rules_proto\">"
             + "rules_proto</a>"
             + "</p>")
-public interface ProtoCommonApi extends StarlarkValue {}
+public interface ProtoCommonApi extends StarlarkValue {
+  @Deprecated
+  @SkylarkCallable(
+      name =
+          "provide_proto_toolchain_in_tools_workspace"
+              + "_do_not_use_or_we_will_break_you_without_mercy",
+      doc = "Indicates whether `@bazel_tools//tools/proto:toolchain` exists.",
+      documented = false,
+      structField = true,
+      disableWithFlag = FlagIdentifier.INCOMPATIBLE_PROVIDE_PROTO_TOOLCHAIN_IN_TOOLS_WORKSPACE)
+  default void provideProtoToolchainInToolsWorkspace() {};
+}