Split ios_application configurations based on --ios_multi_cpus.

Using the new flag works only on ios_application and ios_extension targets,
resulting in their output binaries being "universal" with all given architectures
included.

Internally this is achieved by splitting the "binary" dependency (and its transitive
dependencies) of ios_{application,extension} to be built in one of the architectures
using split transitions. The results are then combined. Since an ios_application may
depend on ios_extension, we transition back to the top-level configuration when
encoutering such a dependency using the newly introduced TOP_LEVEL transition and then
split configurations again.

RELNOTES: --ios_multi_cpus allows building fat ios_applications.

--
MOS_MIGRATED_REVID=88555540

16 files changed, 202 insertions, 35 deletions

diff --git a/src/main/java/com/google/devtools/build/lib/rules/objc/Attribute.java b/src/main/java/com/google/devtools/build/lib/rules/objc/Attribute.java
new file mode 100644
index 0000000000..95e628d624
--- /dev/null
+++ b/src/main/java/com/google/devtools/build/lib/rules/objc/Attribute.java
@@ -0,0 +1,43 @@
+// Copyright 2015 Google Inc. 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.objc;
+
+import com.google.devtools.build.lib.analysis.RuleConfiguredTarget.Mode;
+import com.google.devtools.build.lib.analysis.RuleContext;
+
+/**
+ * Container for an attribute name and access mode such as are commonly passed to
+ * {@link RuleContext#getPrerequisite(String, Mode)} and related methods.
+ */
+public class Attribute {
+  private final String name;
+  private final Mode accessMode;
+
+  /**
+   * Creates an attribute reference with the given name and access mode.
+   */
+  public Attribute(String name, Mode accessMode) {
+    this.name = name;
+    this.accessMode = accessMode;
+  }
+
+  public String getName() {
+    return name;
+  }
+
+  public Mode getAccessMode() {
+    return accessMode;
+  }
+}
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 4e166eaee8..1710c96149 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
@@ -124,9 +124,9 @@ abstract class BinaryLinkingTargetFactory implements RuleConfiguredTargetFactory
         // TODO(bazel-team): Use LIBRARY_STATIC as parameter instead of APPLICATION once objc_binary
         // no longer creates an application bundle
         .addXcodeSettings(xcodeProviderBuilder, objcProvider, productType)
-        .addDependencies(xcodeProviderBuilder, "bundles")
-        .addDependencies(xcodeProviderBuilder, "deps")
-        .addDependencies(xcodeProviderBuilder, "non_propagated_deps")
+        .addDependencies(xcodeProviderBuilder, new Attribute("bundles", Mode.TARGET))
+        .addDependencies(xcodeProviderBuilder, new Attribute("deps", Mode.TARGET))
+        .addDependencies(xcodeProviderBuilder, new Attribute("non_propagated_deps", Mode.TARGET))
         .addFilesToBuild(filesToBuild);
     XcodeProvider xcodeProvider = xcodeProviderBuilder.build();
     xcodeSupport.registerActions(xcodeProvider);
diff --git a/src/main/java/com/google/devtools/build/lib/rules/objc/IosApplication.java b/src/main/java/com/google/devtools/build/lib/rules/objc/IosApplication.java
index d35bfa0618..72a4046437 100644
--- a/src/main/java/com/google/devtools/build/lib/rules/objc/IosApplication.java
+++ b/src/main/java/com/google/devtools/build/lib/rules/objc/IosApplication.java
@@ -15,6 +15,7 @@
 package com.google.devtools.build.lib.rules.objc;
 
 import com.google.common.base.Optional;
+import com.google.common.collect.ImmutableSet;
 import com.google.devtools.build.lib.actions.Artifact;
 import com.google.devtools.build.lib.analysis.RuleConfiguredTarget.Mode;
 import com.google.devtools.build.lib.analysis.RuleConfiguredTargetBuilder;
@@ -26,9 +27,14 @@ import com.google.devtools.build.xcode.common.Platform;
  */
 public class IosApplication extends ReleaseBundlingTargetFactory {
 
+  private static final ImmutableSet<Attribute> DEPENDENCY_ATTRIBUTES =
+      ImmutableSet.of(
+          new Attribute("binary", Mode.SPLIT),
+          new Attribute("extensions", Mode.TARGET));
+
   public IosApplication() {
     super(ReleaseBundlingSupport.APP_BUNDLE_DIR_FORMAT, XcodeProductType.APPLICATION,
-        ExposeAsNestedBundle.NO);
+        ExposeAsNestedBundle.NO, DEPENDENCY_ATTRIBUTES);
   }
 
   @Override
diff --git a/src/main/java/com/google/devtools/build/lib/rules/objc/IosApplicationRule.java b/src/main/java/com/google/devtools/build/lib/rules/objc/IosApplicationRule.java
index 497955ea92..040a81f77f 100644
--- a/src/main/java/com/google/devtools/build/lib/rules/objc/IosApplicationRule.java
+++ b/src/main/java/com/google/devtools/build/lib/rules/objc/IosApplicationRule.java
@@ -18,6 +18,7 @@ import static com.google.devtools.build.lib.packages.Attribute.ConfigurationTran
 import static com.google.devtools.build.lib.packages.Attribute.attr;
 import static com.google.devtools.build.lib.packages.Type.BOOLEAN;
 import static com.google.devtools.build.lib.packages.Type.LABEL;
+import static com.google.devtools.build.lib.packages.Type.LABEL_LIST;
 
 import com.google.devtools.build.lib.analysis.BaseRuleClasses;
 import com.google.devtools.build.lib.analysis.BlazeRule;
@@ -60,6 +61,15 @@ public class IosApplicationRule implements RuleDefinition {
             .allowedRuleClasses("objc_binary")
             .allowedFileTypes()
             .mandatory()
+            .direct_compile_time_input()
+            .cfg(ReleaseBundlingSupport.SPLIT_ARCH_TRANSITION))
+        /* <!-- #BLAZE_RULE(ios_application).ATTRIBUTE(extensions) -->
+        Any extensions to include in the final application.
+        ${SYNOPSIS}
+        <!-- #END_BLAZE_RULE.ATTRIBUTE -->*/
+        .add(attr("extensions", LABEL_LIST)
+            .allowedRuleClasses("ios_extension")
+            .allowedFileTypes()
             .direct_compile_time_input())
         .add(attr("$runner_script_template", LABEL).cfg(HOST)
             .value(env.getLabel("//tools/objc:ios_runner.sh.mac_template")))
diff --git a/src/main/java/com/google/devtools/build/lib/rules/objc/IosExtension.java b/src/main/java/com/google/devtools/build/lib/rules/objc/IosExtension.java
index 163d133189..fa2e8fbef6 100644
--- a/src/main/java/com/google/devtools/build/lib/rules/objc/IosExtension.java
+++ b/src/main/java/com/google/devtools/build/lib/rules/objc/IosExtension.java
@@ -14,6 +14,7 @@
 
 package com.google.devtools.build.lib.rules.objc;
 
+import com.google.common.collect.ImmutableSet;
 import com.google.devtools.build.lib.analysis.RuleConfiguredTarget.Mode;
 import com.google.devtools.build.lib.analysis.RuleContext;
 
@@ -24,7 +25,7 @@ public class IosExtension extends ReleaseBundlingTargetFactory {
 
   public IosExtension() {
     super(ReleaseBundlingSupport.EXTENSION_BUNDLE_DIR_FORMAT, XcodeProductType.EXTENSION,
-        ExposeAsNestedBundle.YES);
+        ExposeAsNestedBundle.YES, ImmutableSet.of(new Attribute("binary", Mode.SPLIT)));
   }
 
   protected OptionsProvider optionsProvider(RuleContext ruleContext) {
diff --git a/src/main/java/com/google/devtools/build/lib/rules/objc/IosExtensionRule.java b/src/main/java/com/google/devtools/build/lib/rules/objc/IosExtensionRule.java
index a3491e0b9d..ca35f478ed 100644
--- a/src/main/java/com/google/devtools/build/lib/rules/objc/IosExtensionRule.java
+++ b/src/main/java/com/google/devtools/build/lib/rules/objc/IosExtensionRule.java
@@ -56,7 +56,8 @@ public class IosExtensionRule implements RuleDefinition {
             .allowedRuleClasses("ios_extension_binary")
             .allowedFileTypes()
             .mandatory()
-            .direct_compile_time_input())
+            .direct_compile_time_input()
+            .cfg(ReleaseBundlingSupport.SPLIT_ARCH_TRANSITION))
         .build();
   }
 }
diff --git a/src/main/java/com/google/devtools/build/lib/rules/objc/IosTest.java b/src/main/java/com/google/devtools/build/lib/rules/objc/IosTest.java
index 1c94e9e14f..b2b836ef60 100644
--- a/src/main/java/com/google/devtools/build/lib/rules/objc/IosTest.java
+++ b/src/main/java/com/google/devtools/build/lib/rules/objc/IosTest.java
@@ -50,6 +50,9 @@ public abstract class IosTest implements RuleConfiguredTargetFactory {
   @VisibleForTesting
   public static final String REQUIRES_SOURCE_ERROR =
       "ios_test requires at least one source file in srcs or non_arc_srcs";
+  @VisibleForTesting
+  public static final String NO_MULTI_CPUS_ERROR =
+      "ios_test cannot be built for multiple CPUs at the same time";
 
   /**
    * Creates a target, including registering actions, just as {@link #create(RuleContext)} does.
@@ -70,6 +73,10 @@ public abstract class IosTest implements RuleConfiguredTargetFactory {
       ruleContext.ruleError(REQUIRES_SOURCE_ERROR);
     }
 
+    if (!ObjcRuleClasses.objcConfiguration(ruleContext).getIosMultiCpus().isEmpty()) {
+      ruleContext.ruleError(NO_MULTI_CPUS_ERROR);
+    }
+
     XcodeProvider.Builder xcodeProviderBuilder = new XcodeProvider.Builder();
     NestedSetBuilder<Artifact> filesToBuild = NestedSetBuilder.<Artifact>stableOrder()
         .addTransitive(common.getStoryboards().getOutputZips())
@@ -132,9 +139,9 @@ public abstract class IosTest implements RuleConfiguredTargetFactory {
 
     new XcodeSupport(ruleContext)
         .addXcodeSettings(xcodeProviderBuilder, common.getObjcProvider(), productType)
-        .addDependencies(xcodeProviderBuilder, "bundles")
-        .addDependencies(xcodeProviderBuilder, "deps")
-        .addDependencies(xcodeProviderBuilder, "non_propagated_deps")
+        .addDependencies(xcodeProviderBuilder, new Attribute("bundles", Mode.TARGET))
+        .addDependencies(xcodeProviderBuilder, new Attribute("deps", Mode.TARGET))
+        .addDependencies(xcodeProviderBuilder, new Attribute("non_propagated_deps", Mode.TARGET))
         .addFilesToBuild(filesToBuild)
         .registerActions(xcodeProviderBuilder.build());
 
diff --git a/src/main/java/com/google/devtools/build/lib/rules/objc/ObjcBundleLibrary.java b/src/main/java/com/google/devtools/build/lib/rules/objc/ObjcBundleLibrary.java
index 253fe32814..e25e274674 100644
--- a/src/main/java/com/google/devtools/build/lib/rules/objc/ObjcBundleLibrary.java
+++ b/src/main/java/com/google/devtools/build/lib/rules/objc/ObjcBundleLibrary.java
@@ -58,7 +58,7 @@ public class ObjcBundleLibrary implements RuleConfiguredTargetFactory {
     new XcodeSupport(ruleContext)
         .addFilesToBuild(filesToBuild)
         .addXcodeSettings(xcodeProviderBuilder, common.getObjcProvider(), BUNDLE)
-        .addDependencies(xcodeProviderBuilder, "bundles")
+        .addDependencies(xcodeProviderBuilder, new Attribute("bundles", Mode.TARGET))
         .registerActions(xcodeProviderBuilder.build());
 
     ObjcProvider nestedBundleProvider = new ObjcProvider.Builder()
diff --git a/src/main/java/com/google/devtools/build/lib/rules/objc/ObjcCommandLineOptions.java b/src/main/java/com/google/devtools/build/lib/rules/objc/ObjcCommandLineOptions.java
index 2e42ff9bd4..8937340c7c 100644
--- a/src/main/java/com/google/devtools/build/lib/rules/objc/ObjcCommandLineOptions.java
+++ b/src/main/java/com/google/devtools/build/lib/rules/objc/ObjcCommandLineOptions.java
@@ -17,9 +17,13 @@ package com.google.devtools.build.lib.rules.objc;
 import static com.google.devtools.build.xcode.common.BuildOptionsUtil.DEFAULT_OPTIONS_NAME;
 
 import com.google.common.annotations.VisibleForTesting;
+import com.google.common.collect.ImmutableList;
 import com.google.common.collect.Multimap;
+import com.google.devtools.build.lib.analysis.config.BuildOptions;
 import com.google.devtools.build.lib.analysis.config.FragmentOptions;
+import com.google.devtools.build.lib.packages.Attribute.SplitTransition;
 import com.google.devtools.build.lib.syntax.Label;
+import com.google.devtools.common.options.Converters.CommaSeparatedOptionListConverter;
 import com.google.devtools.common.options.Option;
 
 import java.util.List;
@@ -92,8 +96,28 @@ public class
       help = "Enable checking for memory leaks in ios_test targets.")
   public boolean runMemleaks;
 
+  @Option(name = "ios_multi_cpus",
+      converter = CommaSeparatedOptionListConverter.class,
+      defaultValue = "",
+      category = "flags",
+      help = "Comma-separated list of architectures to build an ios_application with. The result "
+          + "is a universal binary containing all specified architectures.")
+  public List<String> iosMultiCpus;
+
+  @Option(name = "ios_split_cpu",
+      defaultValue = "",
+      category = "undocumented",
+      help =
+          "Don't set this value from the command line - it is derived from  ios_multi_cpus only.")
+  public String iosSplitCpu;
+
   @VisibleForTesting static final String DEFAULT_MINIMUM_IOS = "7.0";
 
   @Override
   public void addAllLabels(Multimap<String, Label> labelMap) {}
+
+  @Override
+  public List<SplitTransition<BuildOptions>> getPotentialSplitTransitions() {
+    return ImmutableList.of(ReleaseBundlingSupport.SPLIT_ARCH_TRANSITION);
+  }
 }
diff --git a/src/main/java/com/google/devtools/build/lib/rules/objc/ObjcConfiguration.java b/src/main/java/com/google/devtools/build/lib/rules/objc/ObjcConfiguration.java
index 4f8b3f5f27..e452ddb38c 100644
--- a/src/main/java/com/google/devtools/build/lib/rules/objc/ObjcConfiguration.java
+++ b/src/main/java/com/google/devtools/build/lib/rules/objc/ObjcConfiguration.java
@@ -18,7 +18,10 @@ import com.google.common.annotations.VisibleForTesting;
 import com.google.common.base.Preconditions;
 import com.google.common.collect.ImmutableList;
 import com.google.devtools.build.lib.analysis.config.BuildConfiguration;
+import com.google.devtools.build.lib.analysis.config.BuildOptions;
 import com.google.devtools.build.lib.analysis.config.CompilationMode;
+import com.google.devtools.build.lib.events.Event;
+import com.google.devtools.build.lib.events.EventHandler;
 import com.google.devtools.build.lib.syntax.Label;
 import com.google.devtools.build.xcode.common.Platform;
 
@@ -53,6 +56,8 @@ public class ObjcConfiguration extends BuildConfiguration.Fragment {
   private final boolean runMemleaks;
   private final List<String> copts;
   private final CompilationMode compilationMode;
+  private final List<String> iosMultiCpus;
+  private final String iosSplitCpu;
 
   // We only load this label if coverage mode is enabled. That is know as part of the
   // BuildConfiguration. This label needs to be part of a configuration because only configurations
@@ -79,6 +84,8 @@ public class ObjcConfiguration extends BuildConfiguration.Fragment {
     this.copts = ImmutableList.copyOf(objcOptions.copts);
     this.compilationMode = Preconditions.checkNotNull(options.compilationMode, "compilationMode");
     this.gcovLabel = gcovLabel;
+    this.iosMultiCpus = Preconditions.checkNotNull(objcOptions.iosMultiCpus, "iosMultiCpus");
+    this.iosSplitCpu = Preconditions.checkNotNull(objcOptions.iosSplitCpu, "iosSplitCpu");
   }
 
   public String getIosSdkVersion() {
@@ -106,7 +113,7 @@ public class ObjcConfiguration extends BuildConfiguration.Fragment {
   }
 
   public String getIosCpu() {
-    return iosCpu;
+    return iosSplitCpu.isEmpty() ? iosCpu : iosSplitCpu;
   }
 
   public Platform getPlatform() {
@@ -164,6 +171,14 @@ public class ObjcConfiguration extends BuildConfiguration.Fragment {
     return gcovLabel;
   }
 
+  /**
+   * List of all CPUs that this invocation is being built for. Different from {@link #getIosCpu()}
+   * which is the specific CPU <b>this target</b> is being built for.
+   */
+  public List<String> getIosMultiCpus() {
+    return iosMultiCpus;
+  }
+
   @Override
   public String getName() {
     return "Objective-C";
@@ -173,4 +188,18 @@ public class ObjcConfiguration extends BuildConfiguration.Fragment {
   public String cacheKey() {
     return iosSdkVersion;
   }
+
+  @Nullable
+  @Override
+  public String getOutputDirectoryName() {
+    return !iosSplitCpu.isEmpty() ? "ios-" + iosSplitCpu : null;
+  }
+
+  @Override
+  public void reportInvalidOptions(EventHandler reporter, BuildOptions buildOptions) {
+    if (generateDebugSymbols && !iosMultiCpus.isEmpty()) {
+      reporter.handle(Event.error(
+          "--objc_generate_debug_symbols is not supported when --ios_multi_cpus is set"));
+    }
+  }
 }
diff --git a/src/main/java/com/google/devtools/build/lib/rules/objc/ObjcImport.java b/src/main/java/com/google/devtools/build/lib/rules/objc/ObjcImport.java
index 616bfc0b9a..631def29c4 100644
--- a/src/main/java/com/google/devtools/build/lib/rules/objc/ObjcImport.java
+++ b/src/main/java/com/google/devtools/build/lib/rules/objc/ObjcImport.java
@@ -58,7 +58,7 @@ public class ObjcImport implements RuleConfiguredTargetFactory {
 
     new XcodeSupport(ruleContext)
         .addXcodeSettings(xcodeProviderBuilder, common.getObjcProvider(), LIBRARY_STATIC)
-        .addDependencies(xcodeProviderBuilder, "bundles")
+        .addDependencies(xcodeProviderBuilder, new Attribute("bundles", Mode.TARGET))
         .registerActions(xcodeProviderBuilder.build())
         .addFilesToBuild(filesToBuild);
 
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 cf4bfcb3ec..2271f4931f 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
@@ -101,9 +101,9 @@ public class ObjcLibrary implements RuleConfiguredTargetFactory {
     new XcodeSupport(ruleContext)
         .addFilesToBuild(filesToBuild)
         .addXcodeSettings(xcodeProviderBuilder, common.getObjcProvider(), LIBRARY_STATIC)
-        .addDependencies(xcodeProviderBuilder, "bundles")
-        .addDependencies(xcodeProviderBuilder, "deps")
-        .addDependencies(xcodeProviderBuilder, "non_propagated_deps")
+        .addDependencies(xcodeProviderBuilder, new Attribute("bundles", Mode.TARGET))
+        .addDependencies(xcodeProviderBuilder, new Attribute("deps", Mode.TARGET))
+        .addDependencies(xcodeProviderBuilder, new Attribute("non_propagated_deps", Mode.TARGET))
         .registerActions(xcodeProviderBuilder.build());
 
     return common.configuredTarget(
diff --git a/src/main/java/com/google/devtools/build/lib/rules/objc/ObjcRuleClasses.java b/src/main/java/com/google/devtools/build/lib/rules/objc/ObjcRuleClasses.java
index 5e28bfb414..d253cf693a 100644
--- a/src/main/java/com/google/devtools/build/lib/rules/objc/ObjcRuleClasses.java
+++ b/src/main/java/com/google/devtools/build/lib/rules/objc/ObjcRuleClasses.java
@@ -384,7 +384,7 @@ public class ObjcRuleClasses {
           <!-- #END_BLAZE_RULE.ATTRIBUTE -->*/
           .add(attr("bundles", LABEL_LIST)
               .direct_compile_time_input()
-              .allowedRuleClasses("objc_bundle", "objc_bundle_library", "ios_extension")
+              .allowedRuleClasses("objc_bundle", "objc_bundle_library")
               .allowedFileTypes())
           .add(attr("$momczip_deploy", LABEL).cfg(HOST)
               .value(env.getLabel("//tools/objc:momczip_deploy.jar")))
diff --git a/src/main/java/com/google/devtools/build/lib/rules/objc/ReleaseBundlingSupport.java b/src/main/java/com/google/devtools/build/lib/rules/objc/ReleaseBundlingSupport.java
index 6a6e74a830..67befa23d4 100644
--- a/src/main/java/com/google/devtools/build/lib/rules/objc/ReleaseBundlingSupport.java
+++ b/src/main/java/com/google/devtools/build/lib/rules/objc/ReleaseBundlingSupport.java
@@ -33,9 +33,11 @@ import com.google.devtools.build.lib.analysis.actions.CustomCommandLine;
 import com.google.devtools.build.lib.analysis.actions.SpawnAction;
 import com.google.devtools.build.lib.analysis.actions.TemplateExpansionAction;
 import com.google.devtools.build.lib.analysis.actions.TemplateExpansionAction.Substitution;
+import com.google.devtools.build.lib.analysis.config.BuildOptions;
 import com.google.devtools.build.lib.collect.nestedset.NestedSet;
 import com.google.devtools.build.lib.collect.nestedset.NestedSetBuilder;
 import com.google.devtools.build.lib.collect.nestedset.Order;
+import com.google.devtools.build.lib.packages.Attribute.SplitTransition;
 import com.google.devtools.build.lib.packages.ImplicitOutputsFunction.SafeImplicitOutputsFunction;
 import com.google.devtools.build.lib.packages.Type;
 import com.google.devtools.build.lib.rules.objc.ObjcActionsBuilder.ExtraActoolArgs;
@@ -68,6 +70,35 @@ public final class ReleaseBundlingSupport {
    */
   public static final SafeImplicitOutputsFunction IPA = fromTemplates("%{name}.ipa");
 
+  /**
+   * Transition that when applied to a target generates a configured target for each value in
+   * {@code --ios_multi_cpus}, such that {@code --ios_cpu} is set to a different one of those values
+   * in the configured targets.
+   */
+  public static final SplitTransition<BuildOptions> SPLIT_ARCH_TRANSITION =
+      new SplitTransition<BuildOptions>() {
+        @Override
+        public List<BuildOptions> split(BuildOptions buildOptions) {
+          List<String> iosMultiCpus = buildOptions.get(ObjcCommandLineOptions.class).iosMultiCpus;
+          if (iosMultiCpus.isEmpty()) {
+            return ImmutableList.of();
+          }
+
+          ImmutableList.Builder<BuildOptions> splitBuildOptions = ImmutableList.builder();
+          for (String iosCpu : iosMultiCpus) {
+            BuildOptions splitOptions = buildOptions.clone();
+            splitOptions.get(ObjcCommandLineOptions.class).iosSplitCpu = iosCpu;
+            splitBuildOptions.add(splitOptions);
+          }
+          return splitBuildOptions.build();
+        }
+
+        @Override
+        public boolean defaultsToSelf() {
+          return true;
+        }
+      };
+
   @VisibleForTesting
   static final String NO_ASSET_CATALOG_ERROR_FORMAT =
       "a value was specified (%s), but this app does not have any asset catalogs";
@@ -620,8 +651,13 @@ public final class ReleaseBundlingSupport {
         return NestedSetBuilder.emptySet(Order.STABLE_ORDER);
       }
 
-      return ruleContext.getPrerequisite("binary", Mode.TARGET, ObjcProvider.class)
-          .get(ObjcProvider.LINKED_BINARY);
+      NestedSetBuilder<Artifact> linkedBinaries = NestedSetBuilder.stableOrder();
+      for (ObjcProvider provider
+          : ruleContext.getPrerequisites("binary", Mode.DONT_CHECK, ObjcProvider.class)) {
+        linkedBinaries.addTransitive(provider.get(ObjcProvider.LINKED_BINARY));
+      }
+
+      return linkedBinaries.build();
     }
 
     FilesToRunProvider bundleMergeExecutable() {
diff --git a/src/main/java/com/google/devtools/build/lib/rules/objc/ReleaseBundlingTargetFactory.java b/src/main/java/com/google/devtools/build/lib/rules/objc/ReleaseBundlingTargetFactory.java
index 4bae44af82..88481393b9 100644
--- a/src/main/java/com/google/devtools/build/lib/rules/objc/ReleaseBundlingTargetFactory.java
+++ b/src/main/java/com/google/devtools/build/lib/rules/objc/ReleaseBundlingTargetFactory.java
@@ -17,9 +17,9 @@ package com.google.devtools.build.lib.rules.objc;
 import static com.google.devtools.build.lib.rules.objc.ObjcProvider.MERGE_ZIP;
 
 import com.google.common.base.Optional;
+import com.google.common.collect.ImmutableSet;
 import com.google.devtools.build.lib.actions.Artifact;
 import com.google.devtools.build.lib.analysis.ConfiguredTarget;
-import com.google.devtools.build.lib.analysis.RuleConfiguredTarget.Mode;
 import com.google.devtools.build.lib.analysis.RuleConfiguredTargetBuilder;
 import com.google.devtools.build.lib.analysis.RuleContext;
 import com.google.devtools.build.lib.collect.nestedset.NestedSetBuilder;
@@ -40,19 +40,22 @@ public abstract class ReleaseBundlingTargetFactory implements RuleConfiguredTarg
   private final String bundleDirFormat;
   private final XcodeProductType xcodeProductType;
   private final ExposeAsNestedBundle exposeAsNestedBundle;
+  private final ImmutableSet<Attribute> dependencyAttributes;
 
   /**
    * @param bundleDirFormat format string representing the bundle's directory with a single
    *     placeholder for the target name (e.g. {@code "Payload/%s.app"})
    * @param exposeAsNestedBundle whether to export an {@link ObjcProvider} with this target as a
-   *    nested bundle
+   * @param dependencyAttributes all attributes that contain dependencies of this rule. Any
+   *    dependency so listed must expose {@link XcodeProvider} and {@link ObjcProvider}.
    */
   public ReleaseBundlingTargetFactory(String bundleDirFormat,
       XcodeProductType xcodeProductType,
-      ExposeAsNestedBundle exposeAsNestedBundle) {
+      ExposeAsNestedBundle exposeAsNestedBundle, ImmutableSet<Attribute> dependencyAttributes) {
     this.bundleDirFormat = bundleDirFormat;
     this.xcodeProductType = xcodeProductType;
     this.exposeAsNestedBundle = exposeAsNestedBundle;
+    this.dependencyAttributes = dependencyAttributes;
   }
 
   @Override
@@ -71,14 +74,16 @@ public abstract class ReleaseBundlingTargetFactory implements RuleConfiguredTarg
         .addFilesToBuild(filesToBuild)
         .validateAttributes();
 
-    new XcodeSupport(ruleContext)
+    XcodeSupport xcodeSupport = new XcodeSupport(ruleContext)
         .addFilesToBuild(filesToBuild)
-        .addXcodeSettings(
-            xcodeProviderBuilder, common.getObjcProvider(), xcodeProductType)
-        .addDummySource(xcodeProviderBuilder)
-        .addDependencies(xcodeProviderBuilder, "binary")
-        .registerActions(xcodeProviderBuilder.build());
+        .addXcodeSettings(xcodeProviderBuilder, common.getObjcProvider(), xcodeProductType)
+        .addDummySource(xcodeProviderBuilder);
 
+    for (Attribute attribute : dependencyAttributes) {
+      xcodeSupport.addDependencies(xcodeProviderBuilder, attribute);
+    }
+
+    xcodeSupport.registerActions(xcodeProviderBuilder.build());
 
     Optional<ObjcProvider> exposedObjcProvider;
     if (exposeAsNestedBundle == ExposeAsNestedBundle.YES) {
@@ -112,10 +117,13 @@ public abstract class ReleaseBundlingTargetFactory implements RuleConfiguredTarg
       ReleaseBundlingSupport releaseBundlingSupport) {}
 
   private ObjcCommon common(RuleContext ruleContext) {
-    return new ObjcCommon.Builder(ruleContext)
-        .setIntermediateArtifacts(ObjcRuleClasses.intermediateArtifacts(ruleContext))
-        .addDepObjcProviders(
-            ruleContext.getPrerequisites("binary", Mode.TARGET, ObjcProvider.class))
-        .build();
+    ObjcCommon.Builder builder = new ObjcCommon.Builder(ruleContext)
+        .setIntermediateArtifacts(ObjcRuleClasses.intermediateArtifacts(ruleContext));
+    for (Attribute attribute : dependencyAttributes) {
+      builder.addDepObjcProviders(
+          ruleContext.getPrerequisites(
+              attribute.getName(), attribute.getAccessMode(), ObjcProvider.class));
+    }
+    return builder.build();
   }
 }
diff --git a/src/main/java/com/google/devtools/build/lib/rules/objc/XcodeSupport.java b/src/main/java/com/google/devtools/build/lib/rules/objc/XcodeSupport.java
index ca2524a37b..16cc88bb1e 100644
--- a/src/main/java/com/google/devtools/build/lib/rules/objc/XcodeSupport.java
+++ b/src/main/java/com/google/devtools/build/lib/rules/objc/XcodeSupport.java
@@ -21,6 +21,7 @@ import com.google.devtools.build.lib.analysis.RuleConfiguredTarget.Mode;
 import com.google.devtools.build.lib.analysis.RuleContext;
 import com.google.devtools.build.lib.collect.nestedset.NestedSetBuilder;
 import com.google.devtools.build.lib.packages.ImplicitOutputsFunction.SafeImplicitOutputsFunction;
+import com.google.devtools.build.lib.rules.objc.XcodeProvider.Builder;
 
 /**
  * Support for Objc rule types that export an Xcode provider or generate xcode project files.
@@ -104,9 +105,10 @@ public final class XcodeSupport {
    *
    * @return this xcode support
    */
-  XcodeSupport addDependencies(XcodeProvider.Builder xcodeProviderBuilder, String attribute) {
-    xcodeProviderBuilder
-        .addDependencies(ruleContext.getPrerequisites(attribute, Mode.TARGET, XcodeProvider.class));
+  XcodeSupport addDependencies(Builder xcodeProviderBuilder, Attribute attribute) {
+    xcodeProviderBuilder.addDependencies(
+        ruleContext.getPrerequisites(
+            attribute.getName(), attribute.getAccessMode(), XcodeProvider.class));
     return this;
   }
 }