Introduce skylark provider for objc.

--
MOS_MIGRATED_REVID=117485208

5 files changed, 121 insertions, 39 deletions

diff --git a/src/main/java/com/google/devtools/build/lib/rules/objc/BinaryLinkingTargetFactory.java b/src/main/java/com/google/devtools/build/lib/rules/objc/BinaryLinkingTargetFactory.java
index 433075199b..0b5b7ba848 100644
--- a/src/main/java/com/google/devtools/build/lib/rules/objc/BinaryLinkingTargetFactory.java
+++ b/src/main/java/com/google/devtools/build/lib/rules/objc/BinaryLinkingTargetFactory.java
@@ -163,7 +163,10 @@ abstract class BinaryLinkingTargetFactory implements RuleConfiguredTargetFactory
             .addProvider(ObjcProvider.class, objcProvider)
             .addProvider(
                 InstrumentedFilesProvider.class,
-                compilationSupport.getInstrumentedFilesProvider(common));
+                compilationSupport.getInstrumentedFilesProvider(common))
+            .addSkylarkTransitiveInfo(
+                ObjcProvider.OBJC_SKYLARK_PROVIDER_NAME,
+                common.getObjcProvider().toSkylarkProvider());
     if (xcTestAppProvider.isPresent()) {
       // TODO(bazel-team): Stop exporting an XcTestAppProvider once objc_binary no longer creates an
       // application bundle.
diff --git a/src/main/java/com/google/devtools/build/lib/rules/objc/ObjcCommon.java b/src/main/java/com/google/devtools/build/lib/rules/objc/ObjcCommon.java
index f48915012d..67c6ccbaff 100644
--- a/src/main/java/com/google/devtools/build/lib/rules/objc/ObjcCommon.java
+++ b/src/main/java/com/google/devtools/build/lib/rules/objc/ObjcCommon.java
@@ -91,6 +91,7 @@ import java.util.Set;
 // classes. Make sure to distinguish rule output (providers, runfiles, ...) from intermediate,
 // rule-internal information. Any provider created by a rule should not be read, only published.
 public final class ObjcCommon {
+  
   /**
    * Provides a way to access attributes that are common to all compilation rules.
    */
@@ -772,5 +773,4 @@ public final class ObjcCommon {
     }
     return errors;
   }
-
 }
diff --git a/src/main/java/com/google/devtools/build/lib/rules/objc/ObjcLibrary.java b/src/main/java/com/google/devtools/build/lib/rules/objc/ObjcLibrary.java
index 6c9d26c9bc..9c03bf3053 100644
--- a/src/main/java/com/google/devtools/build/lib/rules/objc/ObjcLibrary.java
+++ b/src/main/java/com/google/devtools/build/lib/rules/objc/ObjcLibrary.java
@@ -142,6 +142,8 @@ public class ObjcLibrary implements RuleConfiguredTargetFactory {
         .addProvider(
             CcLinkParamsProvider.class,
             new CcLinkParamsProvider(new ObjcLibraryCcLinkParamsStore(common)))
+        .addSkylarkTransitiveInfo(
+            ObjcProvider.OBJC_SKYLARK_PROVIDER_NAME, common.getObjcProvider().toSkylarkProvider())
         .build();
   }
 }
diff --git a/src/main/java/com/google/devtools/build/lib/rules/objc/ObjcProvider.java b/src/main/java/com/google/devtools/build/lib/rules/objc/ObjcProvider.java
index ee95b6ebee..25e833104b 100644
--- a/src/main/java/com/google/devtools/build/lib/rules/objc/ObjcProvider.java
+++ b/src/main/java/com/google/devtools/build/lib/rules/objc/ObjcProvider.java
@@ -28,6 +28,8 @@ import com.google.devtools.build.lib.collect.nestedset.Order;
 import com.google.devtools.build.lib.concurrent.ThreadSafety.Immutable;
 import com.google.devtools.build.lib.rules.cpp.CppModuleMap;
 import com.google.devtools.build.lib.rules.cpp.LinkerInputs;
+import com.google.devtools.build.lib.syntax.ClassObject.SkylarkClassObject;
+import com.google.devtools.build.lib.syntax.SkylarkNestedSet;
 import com.google.devtools.build.lib.util.Preconditions;
 import com.google.devtools.build.lib.vfs.PathFragment;
 import com.google.devtools.build.xcode.xcodegen.proto.XcodeGenProtos.TargetControl;
@@ -41,31 +43,71 @@ import java.util.Map;
  */
 @Immutable
 public final class ObjcProvider implements TransitiveInfoProvider {
+
+  /**
+   * The name skylark dependents can use to access a Skylark provider containing information
+   * from a target's ObjcProvider.
+   */
+  public static final String OBJC_SKYLARK_PROVIDER_NAME = "objc";
+
   /**
    * Represents one of the things this provider can provide transitively. Things are provided as
    * {@link NestedSet}s of type E.
    */
   public static class Key<E> {
     private final Order order;
+    private final String skylarkKeyName;
+    private final Class<E> type;
 
-    private Key(Order order) {
+    private Key(Order order, String skylarkKeyName, Class<E> type) {
       this.order = Preconditions.checkNotNull(order);
+      this.skylarkKeyName = skylarkKeyName;
+      this.type = type;
+    }
+
+    /**
+     * Returns the name of the collection represented by this key in the Skylark provider.
+     */
+    public String getSkylarkKeyName() {
+      return skylarkKeyName;
     }
+
+    /**
+     * Returns the type of nested set keyed in the ObjcProvider by this key.
+     */
+    public Class<E> getType() {
+      return type;
+    }
+  }
+  
+  /**
+   * All keys in ObjcProvider that will be passed in the corresponding Skylark provider.
+   */
+  // Only keys for Artifact or primitive types can be in the Skylark provider, as other types
+  // are not supported as Skylark types.
+  private ImmutableList<Key<?>> keysForSkylark() {
+    return ImmutableList.<Key<?>>of(LIBRARY, IMPORTED_LIBRARY, LINKED_BINARY, FORCE_LOAD_LIBRARY,
+        FORCE_LOAD_FOR_XCODEGEN, HEADER, SOURCE, DEFINE, ASSET_CATALOG, GENERAL_RESOURCE_FILE,
+        SDK_DYLIB, XCDATAMODEL, MODULE_MAP, MERGE_ZIP, FRAMEWORK_FILE, DEBUG_SYMBOLS,
+        BREAKPAD_FILE, STORYBOARD, XIB, STRINGS, LINKOPT, J2OBJC_LIBRARY);
   }
 
-  public static final Key<Artifact> LIBRARY = new Key<>(LINK_ORDER);
-  public static final Key<Artifact> IMPORTED_LIBRARY = new Key<>(LINK_ORDER);
+  public static final Key<Artifact> LIBRARY = new Key<>(LINK_ORDER, "library", Artifact.class);
+  public static final Key<Artifact> IMPORTED_LIBRARY =
+      new Key<>(LINK_ORDER, "imported_library", Artifact.class);
 
   /**
    * Single-architecture linked binaries to be combined for the final multi-architecture binary.
    */
-  public static final Key<Artifact> LINKED_BINARY = new Key<>(STABLE_ORDER);
+  public static final Key<Artifact> LINKED_BINARY =
+      new Key<>(STABLE_ORDER, "linked_binary", Artifact.class);
 
   /**
    * Indicates which libraries to load with {@code -force_load}. This is a subset of the union of
    * the {@link #LIBRARY} and {@link #IMPORTED_LIBRARY} sets.
    */
-  public static final Key<Artifact> FORCE_LOAD_LIBRARY = new Key<>(LINK_ORDER);
+  public static final Key<Artifact> FORCE_LOAD_LIBRARY =
+      new Key<>(LINK_ORDER, "force_load_library", Artifact.class);
 
   /**
    * Libraries to pass with -force_load flags when setting the linkopts in Xcodegen. This is needed
@@ -75,73 +117,86 @@ public final class ObjcProvider implements TransitiveInfoProvider {
    * {@code BUILT_PRODUCTS_DIR} while those not built by Xcode appear somewhere in the Bazel
    * workspace under {@code WORKSPACE_ROOT}.
    */
-  public static final Key<String> FORCE_LOAD_FOR_XCODEGEN = new Key<>(LINK_ORDER);
+  public static final Key<String> FORCE_LOAD_FOR_XCODEGEN =
+      new Key<>(LINK_ORDER, "force_load_for_xcodegen", String.class);
 
   /**
    * Contains all header files. These may be either public or private headers.
    */
-  public static final Key<Artifact> HEADER = new Key<>(STABLE_ORDER);
+  public static final Key<Artifact> HEADER = new Key<>(STABLE_ORDER, "header", Artifact.class);
 
   /**
    * Contains all source files.
    */
-  public static final Key<Artifact> SOURCE = new Key<>(STABLE_ORDER);
+  public static final Key<Artifact> SOURCE = new Key<>(STABLE_ORDER, "source", Artifact.class);
 
   /**
    * Include search paths specified with {@code -I} on the command line. Also known as header search
    * paths (and distinct from <em>user</em> header search paths).
    */
-  public static final Key<PathFragment> INCLUDE = new Key<>(LINK_ORDER);
+  public static final Key<PathFragment> INCLUDE =
+      new Key<>(LINK_ORDER, "include", PathFragment.class);
 
   /**
    * Include search paths specified with {@code -isystem} on the command line.
    */
-  public static final Key<PathFragment> INCLUDE_SYSTEM = new Key<>(LINK_ORDER);
+  public static final Key<PathFragment> INCLUDE_SYSTEM =
+      new Key<>(LINK_ORDER, "include_system", PathFragment.class);
 
   /**
    * Key for values in {@code defines} attributes. These are passed as {@code -D} flags to all
    * invocations of the compiler for this target and all depending targets.
    */
-  public static final Key<String> DEFINE = new Key<>(STABLE_ORDER);
+  public static final Key<String> DEFINE = new Key<>(STABLE_ORDER, "define", String.class);
 
-  public static final Key<Artifact> ASSET_CATALOG = new Key<>(STABLE_ORDER);
+  public static final Key<Artifact> ASSET_CATALOG =
+      new Key<>(STABLE_ORDER, "asset_catalog", Artifact.class);
 
   /**
    * Added to {@link TargetControl#getGeneralResourceFileList()} when running Xcodegen.
    */
-  public static final Key<Artifact> GENERAL_RESOURCE_FILE = new Key<>(STABLE_ORDER);
+  public static final Key<Artifact> GENERAL_RESOURCE_FILE =
+      new Key<>(STABLE_ORDER, "general_resource_file", Artifact.class);
 
   /**
    * Resource directories added to {@link TargetControl#getGeneralResourceFileList()} when running
    * Xcodegen. When copying files inside resource directories to the app bundle, XCode will preserve
    * the directory structures of the copied files.
    */
-  public static final Key<PathFragment> GENERAL_RESOURCE_DIR = new Key<>(STABLE_ORDER);
+  public static final Key<PathFragment> GENERAL_RESOURCE_DIR =
+      new Key<>(STABLE_ORDER, "general_resource_dir", PathFragment.class);
 
   /**
    * Exec paths of {@code .bundle} directories corresponding to imported bundles to link.
    * These are passed to Xcodegen.
    */
-  public static final Key<PathFragment> BUNDLE_IMPORT_DIR = new Key<>(STABLE_ORDER);
+  public static final Key<PathFragment> BUNDLE_IMPORT_DIR =
+      new Key<>(STABLE_ORDER, "bundle_import_dir", PathFragment.class);
 
   /**
    * Files that are plopped into the final bundle at some arbitrary bundle path. Note that these are
    * not passed to Xcodegen, and these don't include information about where the file originated
    * from.
    */
-  public static final Key<BundleableFile> BUNDLE_FILE = new Key<>(STABLE_ORDER);
+  public static final Key<BundleableFile> BUNDLE_FILE =
+      new Key<>(STABLE_ORDER, "bundle_file", BundleableFile.class);
 
-  public static final Key<PathFragment> XCASSETS_DIR = new Key<>(STABLE_ORDER);
-  public static final Key<String> SDK_DYLIB = new Key<>(STABLE_ORDER);
-  public static final Key<SdkFramework> SDK_FRAMEWORK = new Key<>(STABLE_ORDER);
-  public static final Key<SdkFramework> WEAK_SDK_FRAMEWORK = new Key<>(STABLE_ORDER);
-  public static final Key<Artifact> XCDATAMODEL = new Key<>(STABLE_ORDER);
-  public static final Key<Flag> FLAG = new Key<>(STABLE_ORDER);
+  public static final Key<PathFragment> XCASSETS_DIR =
+      new Key<>(STABLE_ORDER, "xcassets_dir", PathFragment.class);
+  public static final Key<String> SDK_DYLIB = new Key<>(STABLE_ORDER, "sdk_dylib", String.class);
+  public static final Key<SdkFramework> SDK_FRAMEWORK =
+      new Key<>(STABLE_ORDER, "sdk_framework", SdkFramework.class);
+  public static final Key<SdkFramework> WEAK_SDK_FRAMEWORK =
+      new Key<>(STABLE_ORDER, "weak_sdk_framework", SdkFramework.class);
+  public static final Key<Artifact> XCDATAMODEL =
+      new Key<>(STABLE_ORDER, "xcdatamodel", Artifact.class);
+  public static final Key<Flag> FLAG = new Key<>(STABLE_ORDER, "flag", Flag.class);
 
   /**
    * Clang module maps, used to enforce proper use of private header files.
    */
-  public static final Key<Artifact> MODULE_MAP = new Key<>(STABLE_ORDER);
+  public static final Key<Artifact> MODULE_MAP =
+      new Key<>(STABLE_ORDER, "module_map", Artifact.class);
 
   /**
    * Information about this provider's module map, in the form of a {@link CppModuleMap}. This
@@ -149,73 +204,83 @@ public final class ObjcProvider implements TransitiveInfoProvider {
    * get the module maps for direct but not transitive dependencies. You should only add module maps
    * for this key using {@link Builder#addWithoutPropagating}.
    */
-  public static final Key<CppModuleMap> TOP_LEVEL_MODULE_MAP = new Key<>(STABLE_ORDER);
+  public static final Key<CppModuleMap> TOP_LEVEL_MODULE_MAP =
+      new Key<>(STABLE_ORDER, "top_level_module_map", CppModuleMap.class);
 
   /**
    * Merge zips to include in the bundle. The entries of these zip files are included in the final
    * bundle with the same path. The entries in the merge zips should not include the bundle root
    * path (e.g. {@code Foo.app}).
    */
-  public static final Key<Artifact> MERGE_ZIP = new Key<>(STABLE_ORDER);
+  public static final Key<Artifact> MERGE_ZIP =
+      new Key<>(STABLE_ORDER, "merge_zip", Artifact.class);
 
   /**
    * Exec paths of {@code .framework} directories corresponding to frameworks to link. These cause
    * -F arguments (framework search paths) to be added to each compile action, and -framework (link
    * framework) arguments to be added to each link action.
    */
-  public static final Key<PathFragment> FRAMEWORK_DIR = new Key<>(LINK_ORDER);
+  public static final Key<PathFragment> FRAMEWORK_DIR =
+      new Key<>(LINK_ORDER, "framework_dir", PathFragment.class);
 
   /**
    * Files in {@code .framework} directories that should be included as inputs when compiling and
    * linking.
    */
-  public static final Key<Artifact> FRAMEWORK_FILE = new Key<>(STABLE_ORDER);
+  public static final Key<Artifact> FRAMEWORK_FILE =
+      new Key<>(STABLE_ORDER, "framework_file", Artifact.class);
 
   /**
    * Bundles which should be linked in as a nested bundle to the final application.
    */
-  public static final Key<Bundling> NESTED_BUNDLE = new Key<>(STABLE_ORDER);
+  public static final Key<Bundling> NESTED_BUNDLE =
+      new Key<>(STABLE_ORDER, "nested_bundle", Bundling.class);
 
   /**
    * Artifact containing information on debug symbols.
    */
-  public static final Key<Artifact> DEBUG_SYMBOLS = new Key<>(STABLE_ORDER);
+  public static final Key<Artifact> DEBUG_SYMBOLS =
+      new Key<>(STABLE_ORDER, "debug_symbols", Artifact.class);
 
   /**
    * Generated breakpad file containing debug information used by the breakpad crash reporting
    * system.
    */
-  public static final Key<Artifact> BREAKPAD_FILE = new Key<>(STABLE_ORDER);
+  public static final Key<Artifact> BREAKPAD_FILE =
+      new Key<>(STABLE_ORDER, "breakpad_file", Artifact.class);
 
   /**
    * Artifacts for storyboard sources.
    */
-  public static final Key<Artifact> STORYBOARD = new Key<>(STABLE_ORDER);
+  public static final Key<Artifact> STORYBOARD =
+      new Key<>(STABLE_ORDER, "storyboard", Artifact.class);
 
   /**
    * Artifacts for .xib file sources.
    */
-  public static final Key<Artifact> XIB = new Key<>(STABLE_ORDER);
+  public static final Key<Artifact> XIB = new Key<>(STABLE_ORDER, "xib", Artifact.class);
 
   /**
    * Artifacts for strings source files.
    */
-  public static final Key<Artifact> STRINGS = new Key<>(STABLE_ORDER);
+  public static final Key<Artifact> STRINGS = new Key<>(STABLE_ORDER, "strings", Artifact.class);
 
   /**
    * Linking information from cc dependencies.
    */
-  public static final Key<LinkerInputs.LibraryToLink> CC_LIBRARY = new Key<>(LINK_ORDER);
+  public static final Key<LinkerInputs.LibraryToLink> CC_LIBRARY =
+      new Key<>(LINK_ORDER, "cc_library", LinkerInputs.LibraryToLink.class);
 
   /**
    * Linking options from dependencies.
    */
-  public static final Key<String> LINKOPT = new Key<>(LINK_ORDER);
+  public static final Key<String> LINKOPT = new Key<>(LINK_ORDER, "linkopt", String.class);
 
   /**
    * Static libraries that are built from J2ObjC-translated Java code.
    */
-  public static final Key<Artifact> J2OBJC_LIBRARY = new Key<>(LINK_ORDER);
+  public static final Key<Artifact> J2OBJC_LIBRARY =
+      new Key<>(LINK_ORDER, "j2objc_library", Artifact.class);
 
   /**
    * Flags that apply to a transitive build dependency tree. Each item in the enum corresponds to a
@@ -285,6 +350,18 @@ public final class ObjcProvider implements TransitiveInfoProvider {
   }
 
   /**
+   * Returns a {@code SkylarkClassObject} containing values from this provider that is suitable
+   * for a skylark provider.
+   */
+  public SkylarkClassObject toSkylarkProvider() {
+    ImmutableMap.Builder<String, Object> providerBuilder = ImmutableMap.<String, Object>builder();
+    for (Key<?> key : keysForSkylark()) {
+      providerBuilder.put(key.getSkylarkKeyName(), new SkylarkNestedSet(key.getType(), get(key)));
+    }
+    return new SkylarkClassObject(providerBuilder.build(), "No such attribute '%s'");
+  }
+  
+  /**
    * A builder for this context with an API that is optimized for collecting information from
    * several transitive dependencies.
    */
diff --git a/src/main/java/com/google/devtools/build/lib/syntax/SkylarkNestedSet.java b/src/main/java/com/google/devtools/build/lib/syntax/SkylarkNestedSet.java
index f3e8c59df2..25ef2865e7 100644
--- a/src/main/java/com/google/devtools/build/lib/syntax/SkylarkNestedSet.java
+++ b/src/main/java/com/google/devtools/build/lib/syntax/SkylarkNestedSet.java
@@ -176,7 +176,7 @@ public final class SkylarkNestedSet implements Iterable<Object>, SkylarkValue {
    * A not type safe constructor for SkylarkNestedSet, specifying type as a Java class.
    * It's discouraged to use it unless type generic safety is guaranteed from the caller side.
    */
-  SkylarkNestedSet(Class<?> contentType, NestedSet<?> set) {
+  public SkylarkNestedSet(Class<?> contentType, NestedSet<?> set) {
     this(SkylarkType.of(contentType), set);
   }