Migrate remaining assorted skylark types to skylarkbuildapi

RELNOTES: None.
PiperOrigin-RevId: 200100871

23 files changed, 465 insertions, 180 deletions

diff --git a/src/main/java/com/google/devtools/build/lib/BUILD b/src/main/java/com/google/devtools/build/lib/BUILD
index 352dd39972..b3723d09f4 100644
--- a/src/main/java/com/google/devtools/build/lib/BUILD
+++ b/src/main/java/com/google/devtools/build/lib/BUILD
@@ -580,6 +580,7 @@ java_library(
         "//src/main/java/com/google/devtools/build/lib/shell",
         "//src/main/java/com/google/devtools/build/lib/skyframe/serialization/autocodec",
         "//src/main/java/com/google/devtools/build/lib/skylarkbuildapi",
+        "//src/main/java/com/google/devtools/build/lib/skylarkbuildapi/platform",
         "//src/main/java/com/google/devtools/build/lib/skylarkbuildapi/test",
         "//src/main/java/com/google/devtools/build/lib/vfs",
         "//src/main/java/com/google/devtools/build/skyframe",
@@ -888,6 +889,7 @@ java_library(
         "//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/skyframe/serialization/autocodec",
+        "//src/main/java/com/google/devtools/build/lib/skylarkbuildapi",
         "//src/main/java/com/google/devtools/build/lib/vfs",
         "//src/main/java/com/google/devtools/common/options",
         "//third_party:auto_value",
@@ -1111,6 +1113,7 @@ java_library(
         "//src/main/java/com/google/devtools/build/lib/buildeventstream",
         "//src/main/java/com/google/devtools/build/lib/buildeventstream/proto:build_event_stream_proto",
         "//src/main/java/com/google/devtools/build/lib/concurrent",
+        "//src/main/java/com/google/devtools/build/lib/skylarkbuildapi/test",
         "//src/main/java/com/google/devtools/build/lib/vfs",
         "//src/main/protobuf:test_status_java_proto",
         "//third_party:guava",
diff --git a/src/main/java/com/google/devtools/build/lib/analysis/PlatformConfiguration.java b/src/main/java/com/google/devtools/build/lib/analysis/PlatformConfiguration.java
index b1d40f5be7..bd68b48e3e 100644
--- a/src/main/java/com/google/devtools/build/lib/analysis/PlatformConfiguration.java
+++ b/src/main/java/com/google/devtools/build/lib/analysis/PlatformConfiguration.java
@@ -19,20 +19,14 @@ import com.google.devtools.build.lib.analysis.config.BuildConfiguration;
 import com.google.devtools.build.lib.cmdline.Label;
 import com.google.devtools.build.lib.concurrent.ThreadSafety;
 import com.google.devtools.build.lib.skyframe.serialization.autocodec.AutoCodec;
-import com.google.devtools.build.lib.skylarkinterface.SkylarkCallable;
-import com.google.devtools.build.lib.skylarkinterface.SkylarkModule;
-import com.google.devtools.build.lib.skylarkinterface.SkylarkModuleCategory;
+import com.google.devtools.build.lib.skylarkbuildapi.platform.PlatformConfigurationApi;
 import java.util.List;
 
 /** A configuration fragment describing the current platform configuration. */
 @AutoCodec
 @ThreadSafety.Immutable
-@SkylarkModule(
-  name = "platform",
-  doc = "The platform configuration.",
-  category = SkylarkModuleCategory.CONFIGURATION_FRAGMENT
-)
-public class PlatformConfiguration extends BuildConfiguration.Fragment {
+public class PlatformConfiguration extends BuildConfiguration.Fragment
+    implements PlatformConfigurationApi {
   private final Label hostPlatform;
   private final ImmutableList<String> extraExecutionPlatforms;
   private final ImmutableList<Label> targetPlatforms;
@@ -53,7 +47,7 @@ public class PlatformConfiguration extends BuildConfiguration.Fragment {
     this.enabledToolchainTypes = enabledToolchainTypes;
   }
 
-  @SkylarkCallable(name = "host_platform", structField = true, doc = "The current host platform")
+  @Override
   public Label getHostPlatform() {
     return hostPlatform;
   }
@@ -66,7 +60,7 @@ public class PlatformConfiguration extends BuildConfiguration.Fragment {
     return extraExecutionPlatforms;
   }
 
-  @SkylarkCallable(name = "platforms", structField = true, doc = "The current target platforms")
+  @Override
   public ImmutableList<Label> getTargetPlatforms() {
     return targetPlatforms;
   }
@@ -79,11 +73,7 @@ public class PlatformConfiguration extends BuildConfiguration.Fragment {
     return extraToolchains;
   }
 
-  @SkylarkCallable(
-    name = "enabled_toolchain_types",
-    structField = true,
-    doc = "The set of toolchain types enabled for platform-based toolchain selection."
-  )
+  @Override
   public List<Label> getEnabledToolchainTypes() {
     return enabledToolchainTypes;
   }
diff --git a/src/main/java/com/google/devtools/build/lib/analysis/ToolchainContext.java b/src/main/java/com/google/devtools/build/lib/analysis/ToolchainContext.java
index a53b79950e..d73bc22245 100644
--- a/src/main/java/com/google/devtools/build/lib/analysis/ToolchainContext.java
+++ b/src/main/java/com/google/devtools/build/lib/analysis/ToolchainContext.java
@@ -32,8 +32,7 @@ import com.google.devtools.build.lib.concurrent.ThreadSafety.ThreadSafe;
 import com.google.devtools.build.lib.events.Location;
 import com.google.devtools.build.lib.packages.Attribute;
 import com.google.devtools.build.lib.skyframe.ConfiguredTargetAndData;
-import com.google.devtools.build.lib.skylarkinterface.SkylarkModule;
-import com.google.devtools.build.lib.skylarkinterface.SkylarkModuleCategory;
+import com.google.devtools.build.lib.skylarkbuildapi.ToolchainContextApi;
 import com.google.devtools.build.lib.skylarkinterface.SkylarkPrinter;
 import com.google.devtools.build.lib.skylarkinterface.SkylarkValue;
 import com.google.devtools.build.lib.syntax.EvalException;
@@ -48,12 +47,7 @@ import javax.annotation.Nullable;
 /** Contains toolchain-related information needed for a {@link RuleContext}. */
 @Immutable
 @ThreadSafe
-@SkylarkModule(
-  name = "ToolchainContext",
-  category = SkylarkModuleCategory.BUILTIN,
-  doc = "Stores toolchains available to a given rule."
-)
-public class ToolchainContext {
+public class ToolchainContext implements ToolchainContextApi {
   public static ToolchainContext create(
       String targetDescription,
       PlatformInfo executionPlatform,
diff --git a/src/main/java/com/google/devtools/build/lib/packages/FilesetEntry.java b/src/main/java/com/google/devtools/build/lib/packages/FilesetEntry.java
index 8b41b8075f..06b7aa2d1d 100644
--- a/src/main/java/com/google/devtools/build/lib/packages/FilesetEntry.java
+++ b/src/main/java/com/google/devtools/build/lib/packages/FilesetEntry.java
@@ -22,7 +22,7 @@ import com.google.common.collect.Lists;
 import com.google.devtools.build.lib.cmdline.Label;
 import com.google.devtools.build.lib.concurrent.ThreadSafety.Immutable;
 import com.google.devtools.build.lib.concurrent.ThreadSafety.ThreadSafe;
-import com.google.devtools.build.lib.skylarkinterface.SkylarkModule;
+import com.google.devtools.build.lib.skylarkbuildapi.FilesetEntryApi;
 import com.google.devtools.build.lib.skylarkinterface.SkylarkPrinter;
 import com.google.devtools.build.lib.skylarkinterface.SkylarkValue;
 import com.google.devtools.build.lib.vfs.PathFragment;
@@ -37,13 +37,9 @@ import javax.annotation.Nullable;
 /**
  * FilesetEntry is a value object used to represent a "FilesetEntry" inside a "Fileset" BUILD rule.
  */
-@SkylarkModule(
-    name = "FilesetEntry",
-    doc = "",
-    documented = false)
 @Immutable
 @ThreadSafe
-public final class FilesetEntry implements SkylarkValue {
+public final class FilesetEntry implements SkylarkValue, FilesetEntryApi {
 
   public static final SymlinkBehavior DEFAULT_SYMLINK_BEHAVIOR = SymlinkBehavior.COPY;
   public static final String DEFAULT_STRIP_PREFIX = ".";
diff --git a/src/main/java/com/google/devtools/build/lib/rules/cpp/CcExecutionDynamicLibraries.java b/src/main/java/com/google/devtools/build/lib/rules/cpp/CcExecutionDynamicLibraries.java
index fbf52685eb..1f488d31be 100644
--- a/src/main/java/com/google/devtools/build/lib/rules/cpp/CcExecutionDynamicLibraries.java
+++ b/src/main/java/com/google/devtools/build/lib/rules/cpp/CcExecutionDynamicLibraries.java
@@ -19,19 +19,12 @@ import com.google.devtools.build.lib.collect.nestedset.NestedSetBuilder;
 import com.google.devtools.build.lib.collect.nestedset.Order;
 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.skylarkinterface.SkylarkModule;
-import com.google.devtools.build.lib.skylarkinterface.SkylarkModuleCategory;
+import com.google.devtools.build.lib.skylarkbuildapi.cpp.CcExecutionDynamicLibrariesApi;
 
 /** An object that contains the execution-time dynamic libraries of a C++ rule. */
 @Immutable
 @AutoCodec
-@SkylarkModule(
-  name = "cc_execution_dynamic_libraries ",
-  documented = false,
-  category = SkylarkModuleCategory.PROVIDER,
-  doc = "."
-)
-public final class CcExecutionDynamicLibraries {
+public final class CcExecutionDynamicLibraries implements CcExecutionDynamicLibrariesApi {
   public static final CcExecutionDynamicLibraries EMPTY =
       new CcExecutionDynamicLibraries(NestedSetBuilder.<Artifact>emptySet(Order.STABLE_ORDER));
 
diff --git a/src/main/java/com/google/devtools/build/lib/rules/cpp/CcToolchainFeatures.java b/src/main/java/com/google/devtools/build/lib/rules/cpp/CcToolchainFeatures.java
index 80dca05475..18c64003aa 100644
--- a/src/main/java/com/google/devtools/build/lib/rules/cpp/CcToolchainFeatures.java
+++ b/src/main/java/com/google/devtools/build/lib/rules/cpp/CcToolchainFeatures.java
@@ -35,8 +35,7 @@ import com.google.devtools.build.lib.rules.cpp.CcToolchainVariables.StringChunk;
 import com.google.devtools.build.lib.rules.cpp.CcToolchainVariables.StringValueParser;
 import com.google.devtools.build.lib.skyframe.serialization.autocodec.AutoCodec;
 import com.google.devtools.build.lib.skyframe.serialization.autocodec.AutoCodec.VisibleForSerialization;
-import com.google.devtools.build.lib.skylarkinterface.SkylarkModule;
-import com.google.devtools.build.lib.skylarkinterface.SkylarkModuleCategory;
+import com.google.devtools.build.lib.skylarkbuildapi.cpp.FeatureConfigurationApi;
 import com.google.devtools.build.lib.util.Pair;
 import com.google.devtools.build.lib.util.StringUtil;
 import com.google.devtools.build.lib.vfs.PathFragment;
@@ -993,13 +992,7 @@ public class CcToolchainFeatures implements Serializable {
   /** Captures the set of enabled features and action configs for a rule. */
   @Immutable
   @AutoCodec
-  @SkylarkModule(
-    name = "feature_configuration",
-    documented = false,
-    category = SkylarkModuleCategory.BUILTIN,
-    doc = "Class used to construct command lines from CROSSTOOL features."
-  )
-  public static class FeatureConfiguration {
+  public static class FeatureConfiguration implements FeatureConfigurationApi {
     private final ImmutableSet<String> enabledFeatureNames;
     private final ImmutableList<Feature> enabledFeatures;
     private final ImmutableSet<String> enabledActionConfigActionNames;
diff --git a/src/main/java/com/google/devtools/build/lib/rules/cpp/CcToolchainVariables.java b/src/main/java/com/google/devtools/build/lib/rules/cpp/CcToolchainVariables.java
index 093837c046..6733f30263 100644
--- a/src/main/java/com/google/devtools/build/lib/rules/cpp/CcToolchainVariables.java
+++ b/src/main/java/com/google/devtools/build/lib/rules/cpp/CcToolchainVariables.java
@@ -32,8 +32,7 @@ import com.google.devtools.build.lib.concurrent.ThreadSafety.Immutable;
 import com.google.devtools.build.lib.rules.cpp.CcToolchainFeatures.ExpansionException;
 import com.google.devtools.build.lib.skyframe.serialization.autocodec.AutoCodec;
 import com.google.devtools.build.lib.skyframe.serialization.autocodec.AutoCodec.VisibleForSerialization;
-import com.google.devtools.build.lib.skylarkinterface.SkylarkModule;
-import com.google.devtools.build.lib.skylarkinterface.SkylarkModuleCategory;
+import com.google.devtools.build.lib.skylarkbuildapi.cpp.CcToolchainVariablesApi;
 import java.io.Serializable;
 import java.util.ArrayList;
 import java.util.LinkedHashMap;
@@ -49,12 +48,7 @@ import javax.annotation.Nullable;
  * <p>TODO(b/32655571): Investigate cleanup once implicit iteration is not needed. Variables
  * instance could serve as a top level View used to expand all flag_groups.
  */
-@SkylarkModule(
-    name = "variables",
-    documented = false,
-    category = SkylarkModuleCategory.BUILTIN,
-    doc = "Class encapsulating build variables.")
-public abstract class CcToolchainVariables {
+public abstract class CcToolchainVariables implements CcToolchainVariablesApi {
 
   /**
    * A piece of a single string value.
diff --git a/src/main/java/com/google/devtools/build/lib/rules/platform/BUILD b/src/main/java/com/google/devtools/build/lib/rules/platform/BUILD
index f398be1057..c59874970e 100644
--- a/src/main/java/com/google/devtools/build/lib/rules/platform/BUILD
+++ b/src/main/java/com/google/devtools/build/lib/rules/platform/BUILD
@@ -21,6 +21,7 @@ java_library(
         "//src/main/java/com/google/devtools/build/lib/actions",
         "//src/main/java/com/google/devtools/build/lib/analysis/platform",
         "//src/main/java/com/google/devtools/build/lib/analysis/platform:utils",
+        "//src/main/java/com/google/devtools/build/lib/skylarkbuildapi/platform",
         "//third_party:guava",
     ],
 )
diff --git a/src/main/java/com/google/devtools/build/lib/rules/platform/PlatformCommon.java b/src/main/java/com/google/devtools/build/lib/rules/platform/PlatformCommon.java
index e68a461390..b3aff82b62 100644
--- a/src/main/java/com/google/devtools/build/lib/rules/platform/PlatformCommon.java
+++ b/src/main/java/com/google/devtools/build/lib/rules/platform/PlatformCommon.java
@@ -17,40 +17,18 @@ package com.google.devtools.build.lib.rules.platform;
 import com.google.devtools.build.lib.analysis.TemplateVariableInfo;
 import com.google.devtools.build.lib.analysis.platform.ToolchainInfo;
 import com.google.devtools.build.lib.packages.Provider;
-import com.google.devtools.build.lib.skylarkinterface.SkylarkCallable;
-import com.google.devtools.build.lib.skylarkinterface.SkylarkModule;
-import com.google.devtools.build.lib.syntax.SkylarkSignatureProcessor;
+import com.google.devtools.build.lib.skylarkbuildapi.platform.PlatformCommonApi;
 
 /** Skylark namespace used to interact with the platform APIs. */
-@SkylarkModule(
-  name = "platform_common",
-  doc = "Functions for Skylark to interact with the platform APIs."
-)
-public class PlatformCommon {
+public class PlatformCommon implements PlatformCommonApi {
 
-  @SkylarkCallable(
-      name = TemplateVariableInfo.SKYLARK_NAME,
-      doc = "The provider used to retrieve the provider that contains the template variables "
-          + "defined by a particular toolchain, for example by calling "
-          + "ctx.attr._cc_toolchain[platform_common.TemplateVariableInfo].make_variables[<name>]",
-      structField = true
-  )
+  @Override
   public Provider getMakeVariableProvider() {
     return TemplateVariableInfo.PROVIDER;
   }
 
-  @SkylarkCallable(
-    name = ToolchainInfo.SKYLARK_NAME,
-    doc =
-        "The provider constructor for ToolchainInfo. The constructor takes the type of the "
-            + "toolchain, and a map of the toolchain's data.",
-    structField = true
-  )
+  @Override
   public Provider getToolchainInfoConstructor() {
     return ToolchainInfo.PROVIDER;
   }
-
-  static {
-    SkylarkSignatureProcessor.configureSkylarkFunctions(PlatformCommon.class);
-  }
 }
diff --git a/src/main/java/com/google/devtools/build/lib/rules/proto/ProtoConfiguration.java b/src/main/java/com/google/devtools/build/lib/rules/proto/ProtoConfiguration.java
index a5706d9bc2..353d9038af 100644
--- a/src/main/java/com/google/devtools/build/lib/rules/proto/ProtoConfiguration.java
+++ b/src/main/java/com/google/devtools/build/lib/rules/proto/ProtoConfiguration.java
@@ -26,8 +26,7 @@ import com.google.devtools.build.lib.analysis.config.InvalidConfigurationExcepti
 import com.google.devtools.build.lib.cmdline.Label;
 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.skylarkinterface.SkylarkModule;
-import com.google.devtools.build.lib.skylarkinterface.SkylarkModuleCategory;
+import com.google.devtools.build.lib.skylarkbuildapi.ProtoConfigurationApi;
 import com.google.devtools.common.options.Converters;
 import com.google.devtools.common.options.Option;
 import com.google.devtools.common.options.OptionDocumentationCategory;
@@ -40,12 +39,7 @@ import java.util.List;
 @Immutable
 // This module needs to be exported to Skylark so it can be passed as a mandatory host/target
 // configuration fragment in aspect definitions.
-@SkylarkModule(
-  name = "proto",
-  category = SkylarkModuleCategory.CONFIGURATION_FRAGMENT,
-  doc = "A configuration fragment representing protocol buffers."
-)
-public class ProtoConfiguration extends Fragment {
+public class ProtoConfiguration extends Fragment implements ProtoConfigurationApi {
   /** Command line options. */
   @AutoCodec(strategy = AutoCodec.Strategy.PUBLIC_FIELDS)
   public static class Options extends FragmentOptions {
diff --git a/src/main/java/com/google/devtools/build/lib/rules/proto/ProtoSourcesProvider.java b/src/main/java/com/google/devtools/build/lib/rules/proto/ProtoSourcesProvider.java
index 48158ba420..26075cf07f 100644
--- a/src/main/java/com/google/devtools/build/lib/rules/proto/ProtoSourcesProvider.java
+++ b/src/main/java/com/google/devtools/build/lib/rules/proto/ProtoSourcesProvider.java
@@ -21,8 +21,7 @@ import com.google.devtools.build.lib.analysis.TransitiveInfoProvider;
 import com.google.devtools.build.lib.collect.nestedset.NestedSet;
 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.skylarkinterface.SkylarkCallable;
-import com.google.devtools.build.lib.skylarkinterface.SkylarkModule;
+import com.google.devtools.build.lib.skylarkbuildapi.ProtoSourcesProviderApi;
 
 // TODO(carmi): Rename the class to ProtoInfoProvider.
 /**
@@ -31,9 +30,9 @@ import com.google.devtools.build.lib.skylarkinterface.SkylarkModule;
  */
 @AutoValue
 @Immutable
-@SkylarkModule(name = "ProtoSourcesProvider", doc = "")
 @AutoCodec
-public abstract class ProtoSourcesProvider implements TransitiveInfoProvider {
+public abstract class ProtoSourcesProvider
+    implements TransitiveInfoProvider, ProtoSourcesProviderApi<Artifact> {
   /** The name of the field in Skylark used to access this class. */
   public static final String SKYLARK_NAME = "proto";
 
@@ -60,30 +59,18 @@ public abstract class ProtoSourcesProvider implements TransitiveInfoProvider {
    * Transitive imports including weak dependencies This determines the order of "-I" arguments to
    * the protocol compiler, and that is probably important
    */
-  @SkylarkCallable(
-    name = "transitive_imports",
-    doc = "Transitive imports including weak dependencies.",
-    structField = true
-  )
+  @Override
   public abstract NestedSet<Artifact> getTransitiveImports();
 
   /** Returns the proto sources for this rule and all its dependent protocol buffer rules. */
-  @SkylarkCallable(
-    name = "transitive_sources",
-    doc = "Proto sources for this rule and all its dependent protocol buffer rules.",
-    structField = true
-  )
+  @Override
   // TODO(bazel-team): The difference between transitive imports and transitive proto sources
   // should never be used by Skylark or by an Aspect. One of these two should be removed,
   // preferably soon, before Skylark users start depending on them.
   public abstract NestedSet<Artifact> getTransitiveProtoSources();
 
   /** Returns the proto sources from the 'srcs' attribute. */
-  @SkylarkCallable(
-    name = "direct_sources",
-    doc = "Proto sources from the 'srcs' attribute.",
-    structField = true
-  )
+  @Override
   public abstract ImmutableList<Artifact> getDirectProtoSources();
 
   /**
@@ -93,14 +80,7 @@ public abstract class ProtoSourcesProvider implements TransitiveInfoProvider {
    * <p>This must be a set to avoid collecting the same source twice when depending on 2 proxy
    * proto_library's that depend on the same proto_library.
    */
-  @SkylarkCallable(
-    name = "check_deps_sources",
-    doc =
-        "Proto sources from the 'srcs' attribute. If the library is a proxy library "
-            + "that has no sources, it contains the check_deps_sources "
-            + "from this library's direct deps.",
-    structField = true
-  )
+  @Override
   public abstract NestedSet<Artifact> getCheckDepsProtoSources();
 
   /**
@@ -109,11 +89,7 @@ public abstract class ProtoSourcesProvider implements TransitiveInfoProvider {
    * (remember that proto-compiler reads all transitive .proto files, even when producing the
    * direct-srcs descriptor set)
    */
-  @SkylarkCallable(
-    name = "direct_descriptor_set",
-    doc = "The FileDescriptorSet of the direct sources. If no srcs, contains an empty file. ",
-    structField = true
-  )
+  @Override
   public abstract Artifact directDescriptorSet();
 
   /**
@@ -122,25 +98,14 @@ public abstract class ProtoSourcesProvider implements TransitiveInfoProvider {
    * (remember that proto-compiler reads all transitive .proto files, even when producing the
    * direct-srcs descriptor set)
    */
-  @SkylarkCallable(
-    name = "transitive_descriptor_sets",
-    doc =
-        "A set of FileDescriptorSet files of all dependent proto_library rules, and this one's. "
-            + "This is not the same as passing --include_imports to proto-compiler. "
-            + "Will be empty if no dependencies. ",
-    structField = true
-  )
+  @Override
   public abstract NestedSet<Artifact> transitiveDescriptorSets();
 
   /**
    * Directories of .proto sources collected from the transitive closure. These flags will be passed
    * to {@code protoc} in the specified order, via the {@code --proto_path} flag.
    */
-  @SkylarkCallable(
-      name = "transitive_proto_path",
-      doc = "A set of proto source roots collected from the transitive closure of this rule.",
-      structField = true
-  )
+  @Override
   public abstract NestedSet<String> getTransitiveProtoPathFlags();
 
   ProtoSourcesProvider() {}
diff --git a/src/main/java/com/google/devtools/build/lib/rules/test/SkylarkTestingModule.java b/src/main/java/com/google/devtools/build/lib/rules/test/SkylarkTestingModule.java
index a2fa110a85..225298cf5b 100644
--- a/src/main/java/com/google/devtools/build/lib/rules/test/SkylarkTestingModule.java
+++ b/src/main/java/com/google/devtools/build/lib/rules/test/SkylarkTestingModule.java
@@ -15,59 +15,18 @@ package com.google.devtools.build.lib.rules.test;
 
 import com.google.devtools.build.lib.analysis.test.ExecutionInfo;
 import com.google.devtools.build.lib.analysis.test.TestEnvironmentInfo;
-import com.google.devtools.build.lib.skylarkinterface.Param;
-import com.google.devtools.build.lib.skylarkinterface.SkylarkCallable;
-import com.google.devtools.build.lib.skylarkinterface.SkylarkModule;
+import com.google.devtools.build.lib.skylarkbuildapi.test.TestingModuleApi;
 import com.google.devtools.build.lib.syntax.SkylarkDict;
 
 /** A class that exposes testing infrastructure to skylark. */
-@SkylarkModule(
-  name = "testing",
-  doc = "Helper methods for skylark to access testing infrastructure."
-)
-public class SkylarkTestingModule {
+public class SkylarkTestingModule implements TestingModuleApi {
 
-  // TODO(bazel-team): Change this BuiltinFunction to be the actual ExecutionInfo.PROVIDER.
-  @SkylarkCallable(
-    name = "ExecutionInfo",
-    doc =
-        "Creates a new execution info provider. Use this provider to specify special"
-            + "environments requirements needed to run tests.",
-    parameters = {
-      @Param(
-        name = "requirements",
-        type = SkylarkDict.class,
-        named = false,
-        positional = true,
-        doc =
-            "A map of string keys and values to indicate special execution requirements, such as"
-                + " hardware platforms, etc. These keys and values are passed to the executor of"
-                + " the test action as parameters to configure the execution environment."
-      )
-    }
-  )
+  @Override
   public ExecutionInfo executionInfo(SkylarkDict<String, String> requirements) {
     return new ExecutionInfo(requirements);
   }
 
-  // TODO(bazel-team): Change this BuiltinFunction to be the actual TestEnvironmentInfo.PROVIDER.
-  @SkylarkCallable(
-    name = "TestEnvironment",
-    doc =
-        "Creates a new test environment provider. Use this provider to specify extra"
-            + "environment variables to be made available during test execution.",
-    parameters = {
-      @Param(
-        name = "environment",
-        type = SkylarkDict.class,
-        named = false,
-        positional = true,
-        doc =
-            "A map of string keys and values that represent environment variables and their values."
-                + " These will be made available during the test execution."
-      )
-    }
-  )
+  @Override
   public TestEnvironmentInfo testEnvironment(SkylarkDict<String, String> environment) {
     return new TestEnvironmentInfo(environment);
   }
diff --git a/src/main/java/com/google/devtools/build/lib/skylarkbuildapi/FilesetEntryApi.java b/src/main/java/com/google/devtools/build/lib/skylarkbuildapi/FilesetEntryApi.java
new file mode 100644
index 0000000000..53bc977177
--- /dev/null
+++ b/src/main/java/com/google/devtools/build/lib/skylarkbuildapi/FilesetEntryApi.java
@@ -0,0 +1,27 @@
+// Copyright 2018 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.skylarkbuildapi;
+
+import com.google.devtools.build.lib.skylarkinterface.SkylarkModule;
+
+/**
+ * A value object used to represent an entry inside a "Fileset" BUILD rule.
+ */
+@SkylarkModule(
+    name = "FilesetEntry",
+    doc = "",
+    documented = false)
+public interface FilesetEntryApi {
+}
diff --git a/src/main/java/com/google/devtools/build/lib/skylarkbuildapi/ProtoConfigurationApi.java b/src/main/java/com/google/devtools/build/lib/skylarkbuildapi/ProtoConfigurationApi.java
new file mode 100644
index 0000000000..6082ba850b
--- /dev/null
+++ b/src/main/java/com/google/devtools/build/lib/skylarkbuildapi/ProtoConfigurationApi.java
@@ -0,0 +1,29 @@
+// Copyright 2018 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.skylarkbuildapi;
+
+import com.google.devtools.build.lib.skylarkinterface.SkylarkModule;
+import com.google.devtools.build.lib.skylarkinterface.SkylarkModuleCategory;
+
+/**
+ * A configuration fragment representing protocol buffers.
+ */
+@SkylarkModule(
+    name = "proto",
+    category = SkylarkModuleCategory.CONFIGURATION_FRAGMENT,
+    doc = "A configuration fragment representing protocol buffers."
+)
+public interface ProtoConfigurationApi {
+}
diff --git a/src/main/java/com/google/devtools/build/lib/skylarkbuildapi/ProtoSourcesProviderApi.java b/src/main/java/com/google/devtools/build/lib/skylarkbuildapi/ProtoSourcesProviderApi.java
new file mode 100644
index 0000000000..1468663cab
--- /dev/null
+++ b/src/main/java/com/google/devtools/build/lib/skylarkbuildapi/ProtoSourcesProviderApi.java
@@ -0,0 +1,85 @@
+// Copyright 2018 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.skylarkbuildapi;
+
+import com.google.common.collect.ImmutableList;
+import com.google.devtools.build.lib.collect.nestedset.NestedSet;
+import com.google.devtools.build.lib.skylarkinterface.SkylarkCallable;
+import com.google.devtools.build.lib.skylarkinterface.SkylarkModule;
+
+/**
+ * Info object propagating information about protocol buffer sources.
+ */
+@SkylarkModule(name = "ProtoSourcesProvider", doc = "")
+public interface ProtoSourcesProviderApi<FileT extends FileApi> {
+
+  @SkylarkCallable(
+    name = "transitive_imports",
+    doc = "Transitive imports including weak dependencies.",
+    structField = true
+  )
+  public NestedSet<FileT> getTransitiveImports();
+
+  @SkylarkCallable(
+    name = "transitive_sources",
+    doc = "Proto sources for this rule and all its dependent protocol buffer rules.",
+    structField = true
+  )
+  // TODO(bazel-team): The difference between transitive imports and transitive proto sources
+  // should never be used by Skylark or by an Aspect. One of these two should be removed,
+  // preferably soon, before Skylark users start depending on them.
+  public NestedSet<FileT> getTransitiveProtoSources();
+
+  @SkylarkCallable(
+    name = "direct_sources",
+    doc = "Proto sources from the 'srcs' attribute.",
+    structField = true
+  )
+  public ImmutableList<FileT> getDirectProtoSources();
+
+  @SkylarkCallable(
+    name = "check_deps_sources",
+    doc =
+        "Proto sources from the 'srcs' attribute. If the library is a proxy library "
+            + "that has no sources, it contains the check_deps_sources "
+            + "from this library's direct deps.",
+    structField = true
+  )
+  public NestedSet<FileT> getCheckDepsProtoSources();
+
+  @SkylarkCallable(
+    name = "direct_descriptor_set",
+    doc = "The FileDescriptorSet of the direct sources. If no srcs, contains an empty file. ",
+    structField = true
+  )
+  public FileT directDescriptorSet();
+
+  @SkylarkCallable(
+    name = "transitive_descriptor_sets",
+    doc =
+        "A set of FileDescriptorSet files of all dependent proto_library rules, and this one's. "
+            + "This is not the same as passing --include_imports to proto-compiler. "
+            + "Will be empty if no dependencies. ",
+    structField = true
+  )
+  public NestedSet<FileT> transitiveDescriptorSets();
+
+  @SkylarkCallable(
+      name = "transitive_proto_path",
+      doc = "A set of proto source roots collected from the transitive closure of this rule.",
+      structField = true
+  )
+  public NestedSet<String> getTransitiveProtoPathFlags();
+}
diff --git a/src/main/java/com/google/devtools/build/lib/skylarkbuildapi/ToolchainContextApi.java b/src/main/java/com/google/devtools/build/lib/skylarkbuildapi/ToolchainContextApi.java
new file mode 100644
index 0000000000..3441c52044
--- /dev/null
+++ b/src/main/java/com/google/devtools/build/lib/skylarkbuildapi/ToolchainContextApi.java
@@ -0,0 +1,29 @@
+// Copyright 2018 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.skylarkbuildapi;
+
+import com.google.devtools.build.lib.skylarkinterface.SkylarkModule;
+import com.google.devtools.build.lib.skylarkinterface.SkylarkModuleCategory;
+
+/**
+ * Stores toolchains available to a given rule.
+ */
+@SkylarkModule(
+    name = "ToolchainContext",
+    category = SkylarkModuleCategory.BUILTIN,
+    doc = "Stores toolchains available to a given rule."
+)
+public interface ToolchainContextApi {
+}
diff --git a/src/main/java/com/google/devtools/build/lib/skylarkbuildapi/cpp/CcExecutionDynamicLibrariesApi.java b/src/main/java/com/google/devtools/build/lib/skylarkbuildapi/cpp/CcExecutionDynamicLibrariesApi.java
new file mode 100644
index 0000000000..cc1228e498
--- /dev/null
+++ b/src/main/java/com/google/devtools/build/lib/skylarkbuildapi/cpp/CcExecutionDynamicLibrariesApi.java
@@ -0,0 +1,30 @@
+// Copyright 2018 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.skylarkbuildapi.cpp;
+
+import com.google.devtools.build.lib.skylarkinterface.SkylarkModule;
+import com.google.devtools.build.lib.skylarkinterface.SkylarkModuleCategory;
+
+/**
+ * An object that contains the execution-time dynamic libraries of a C++ rule.
+ */
+@SkylarkModule(
+    name = "cc_execution_dynamic_libraries ",
+    documented = false,
+    category = SkylarkModuleCategory.PROVIDER,
+    doc = "."
+)
+public interface CcExecutionDynamicLibrariesApi {
+}
diff --git a/src/main/java/com/google/devtools/build/lib/skylarkbuildapi/cpp/CcToolchainVariablesApi.java b/src/main/java/com/google/devtools/build/lib/skylarkbuildapi/cpp/CcToolchainVariablesApi.java
new file mode 100644
index 0000000000..cadcb3f3fb
--- /dev/null
+++ b/src/main/java/com/google/devtools/build/lib/skylarkbuildapi/cpp/CcToolchainVariablesApi.java
@@ -0,0 +1,29 @@
+// Copyright 2018 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.skylarkbuildapi.cpp;
+
+import com.google.devtools.build.lib.skylarkinterface.SkylarkModule;
+import com.google.devtools.build.lib.skylarkinterface.SkylarkModuleCategory;
+
+/**
+ * Type encapsulating build variables.
+ */
+@SkylarkModule(
+    name = "variables",
+    documented = false,
+    category = SkylarkModuleCategory.BUILTIN,
+    doc = "Class encapsulating build variables.")
+public interface CcToolchainVariablesApi {
+}
diff --git a/src/main/java/com/google/devtools/build/lib/skylarkbuildapi/cpp/FeatureConfigurationApi.java b/src/main/java/com/google/devtools/build/lib/skylarkbuildapi/cpp/FeatureConfigurationApi.java
new file mode 100644
index 0000000000..1940c6efb7
--- /dev/null
+++ b/src/main/java/com/google/devtools/build/lib/skylarkbuildapi/cpp/FeatureConfigurationApi.java
@@ -0,0 +1,30 @@
+// Copyright 2018 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.skylarkbuildapi.cpp;
+
+import com.google.devtools.build.lib.skylarkinterface.SkylarkModule;
+import com.google.devtools.build.lib.skylarkinterface.SkylarkModuleCategory;
+
+/**
+ * Class used to construct command lines from CROSSTOOL features.
+ */
+@SkylarkModule(
+    name = "feature_configuration",
+    documented = false,
+    category = SkylarkModuleCategory.BUILTIN,
+    doc = "Class used to construct command lines from CROSSTOOL features."
+)
+public interface FeatureConfigurationApi {
+}
diff --git a/src/main/java/com/google/devtools/build/lib/skylarkbuildapi/platform/PlatformCommonApi.java b/src/main/java/com/google/devtools/build/lib/skylarkbuildapi/platform/PlatformCommonApi.java
new file mode 100644
index 0000000000..e8dfe9a74b
--- /dev/null
+++ b/src/main/java/com/google/devtools/build/lib/skylarkbuildapi/platform/PlatformCommonApi.java
@@ -0,0 +1,47 @@
+// Copyright 2018 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.skylarkbuildapi.platform;
+
+import com.google.devtools.build.lib.skylarkbuildapi.ProviderApi;
+import com.google.devtools.build.lib.skylarkinterface.SkylarkCallable;
+import com.google.devtools.build.lib.skylarkinterface.SkylarkModule;
+
+/**
+ * Module containing functions to interact with the platform APIs.
+ */
+@SkylarkModule(
+    name = "platform_common",
+    doc = "Functions for Skylark to interact with the platform APIs."
+)
+public interface PlatformCommonApi {
+
+  @SkylarkCallable(
+      name = "TemplateVariableInfo",
+      doc = "The provider used to retrieve the provider that contains the template variables "
+          + "defined by a particular toolchain, for example by calling "
+          + "ctx.attr._cc_toolchain[platform_common.TemplateVariableInfo].make_variables[<name>]",
+      structField = true
+  )
+  public ProviderApi getMakeVariableProvider();
+
+  @SkylarkCallable(
+    name = "ToolchainInfo",
+    doc =
+        "The provider constructor for ToolchainInfo. The constructor takes the type of the "
+            + "toolchain, and a map of the toolchain's data.",
+    structField = true
+  )
+  public ProviderApi getToolchainInfoConstructor();
+}
diff --git a/src/main/java/com/google/devtools/build/lib/skylarkbuildapi/platform/PlatformConfigurationApi.java b/src/main/java/com/google/devtools/build/lib/skylarkbuildapi/platform/PlatformConfigurationApi.java
new file mode 100644
index 0000000000..be7b831548
--- /dev/null
+++ b/src/main/java/com/google/devtools/build/lib/skylarkbuildapi/platform/PlatformConfigurationApi.java
@@ -0,0 +1,46 @@
+// Copyright 2018 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.skylarkbuildapi.platform;
+
+import com.google.common.collect.ImmutableList;
+import com.google.devtools.build.lib.cmdline.Label;
+import com.google.devtools.build.lib.skylarkinterface.SkylarkCallable;
+import com.google.devtools.build.lib.skylarkinterface.SkylarkModule;
+import com.google.devtools.build.lib.skylarkinterface.SkylarkModuleCategory;
+import java.util.List;
+
+/**
+ * The platform configuration.
+ */
+@SkylarkModule(
+    name = "platform",
+    doc = "The platform configuration.",
+    category = SkylarkModuleCategory.CONFIGURATION_FRAGMENT
+)
+public interface PlatformConfigurationApi {
+
+  @SkylarkCallable(name = "host_platform", structField = true, doc = "The current host platform")
+  public Label getHostPlatform();
+
+  @SkylarkCallable(name = "platforms", structField = true, doc = "The current target platforms")
+  public ImmutableList<Label> getTargetPlatforms();
+
+  @SkylarkCallable(
+    name = "enabled_toolchain_types",
+    structField = true,
+    doc = "The set of toolchain types enabled for platform-based toolchain selection."
+  )
+  public List<Label> getEnabledToolchainTypes();
+}
diff --git a/src/main/java/com/google/devtools/build/lib/skylarkbuildapi/test/BUILD b/src/main/java/com/google/devtools/build/lib/skylarkbuildapi/test/BUILD
index a8d8e947de..ef57962d47 100644
--- a/src/main/java/com/google/devtools/build/lib/skylarkbuildapi/test/BUILD
+++ b/src/main/java/com/google/devtools/build/lib/skylarkbuildapi/test/BUILD
@@ -20,6 +20,7 @@ java_library(
     srcs = glob(["*.java"]),
     deps = [
         "//src/main/java/com/google/devtools/build/lib:skylarkinterface",
+        "//src/main/java/com/google/devtools/build/lib:syntax",
         "//src/main/java/com/google/devtools/build/lib/skylarkbuildapi",
         "//third_party:guava",
         "//third_party:jsr305",
diff --git a/src/main/java/com/google/devtools/build/lib/skylarkbuildapi/test/TestingModuleApi.java b/src/main/java/com/google/devtools/build/lib/skylarkbuildapi/test/TestingModuleApi.java
new file mode 100644
index 0000000000..63528c9b56
--- /dev/null
+++ b/src/main/java/com/google/devtools/build/lib/skylarkbuildapi/test/TestingModuleApi.java
@@ -0,0 +1,72 @@
+// Copyright 2018 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.skylarkbuildapi.test;
+
+import com.google.devtools.build.lib.skylarkinterface.Param;
+import com.google.devtools.build.lib.skylarkinterface.SkylarkCallable;
+import com.google.devtools.build.lib.skylarkinterface.SkylarkModule;
+import com.google.devtools.build.lib.syntax.SkylarkDict;
+
+/**
+ * Helper module for accessing test infrastructure.
+ */
+@SkylarkModule(
+    name = "testing",
+    doc = "Helper methods for skylark to access testing infrastructure."
+)
+public interface TestingModuleApi {
+
+  // TODO(bazel-team): Change this function to be the actual ExecutionInfo.PROVIDER.
+  @SkylarkCallable(
+      name = "ExecutionInfo",
+      doc =
+          "Creates a new execution info provider. Use this provider to specify special"
+              + "environments requirements needed to run tests.",
+      parameters = {
+          @Param(
+              name = "requirements",
+              type = SkylarkDict.class,
+              named = false,
+              positional = true,
+              doc =
+                  "A map of string keys and values to indicate special execution requirements,"
+                      + " such as hardware platforms, etc. These keys and values are passed to the"
+                      + " executor of the test action as parameters to configure the execution"
+                      + " environment."
+          )
+      }
+  )
+  public ExecutionInfoApi executionInfo(SkylarkDict<String, String> requirements);
+
+  // TODO(bazel-team): Change this function to be the actual TestEnvironmentInfo.PROVIDER.
+  @SkylarkCallable(
+      name = "TestEnvironment",
+      doc =
+          "Creates a new test environment provider. Use this provider to specify extra"
+              + "environment variables to be made available during test execution.",
+      parameters = {
+          @Param(
+              name = "environment",
+              type = SkylarkDict.class,
+              named = false,
+              positional = true,
+              doc =
+                  "A map of string keys and values that represent environment variables and their"
+                      + " values. These will be made available during the test execution."
+          )
+      }
+  )
+  public TestEnvironmentInfoApi testEnvironment(SkylarkDict<String, String> environment);
+}