Introduce apple_watch2_extension rule for bundling watchOS2 extensions.

This can be used in conjunction with apple_binary to add watchOS2 extensions to an ios application bundle.

This is the majority of the native work for this bundling logic. Before announcing general availability of this feature, we will want to:
1. Iterate with teams who have existing watchOS2 apps to catch any corner-case bugs
2. Introduce a skylark macro to wrap apple_watch2_extension and apple_binary into a single rule; this will both serve as a convenience and ensure users set the appropriate linkopts and platformtype on their apple_binary target.

--
MOS_MIGRATED_REVID=129122855

1 files changed, 176 insertions, 0 deletions

diff --git a/src/main/java/com/google/devtools/build/lib/rules/objc/AppleWatch2Extension.java b/src/main/java/com/google/devtools/build/lib/rules/objc/AppleWatch2Extension.java
new file mode 100644
index 0000000000..d208062813
--- /dev/null
+++ b/src/main/java/com/google/devtools/build/lib/rules/objc/AppleWatch2Extension.java
@@ -0,0 +1,176 @@
+// Copyright 2016 The Bazel Authors. All rights reserved.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//    http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package com.google.devtools.build.lib.rules.objc;
+
+import static com.google.devtools.build.lib.packages.ImplicitOutputsFunction.fromTemplates;
+import static com.google.devtools.build.lib.rules.objc.ObjcProvider.FLAG;
+import static com.google.devtools.build.lib.rules.objc.ObjcProvider.Flag.HAS_WATCH2_EXTENSION;
+import static com.google.devtools.build.lib.rules.objc.ObjcProvider.MERGE_ZIP;
+import static com.google.devtools.build.lib.rules.objc.ObjcRuleClasses.WatchApplicationBundleRule.WATCH_APP_NAME_ATTR;
+
+import com.google.common.collect.HashMultiset;
+import com.google.common.collect.ImmutableList;
+import com.google.common.collect.ImmutableSet;
+import com.google.common.collect.Multiset;
+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;
+import com.google.devtools.build.lib.packages.ImplicitOutputsFunction.SafeImplicitOutputsFunction;
+import com.google.devtools.build.lib.rules.RuleConfiguredTargetFactory;
+import com.google.devtools.build.lib.rules.objc.WatchUtils.WatchOSVersion;
+import com.google.devtools.build.lib.rules.test.InstrumentedFilesCollector;
+import com.google.devtools.build.lib.rules.test.InstrumentedFilesProvider;
+import com.google.devtools.build.lib.syntax.Type;
+
+/** Implementation for {@code apple_watch2_extension}. */
+public class AppleWatch2Extension implements RuleConfiguredTargetFactory {
+
+  /** Template for the containing application folder. */
+  public static final SafeImplicitOutputsFunction APP_NAME_IPA = fromTemplates("%{app_name}.ipa");
+
+  @Override
+  public ConfiguredTarget create(RuleContext ruleContext)
+      throws InterruptedException, RuleErrorException {
+    validateAttributes(ruleContext);
+
+    ObjcProvider.Builder exposedObjcProviderBuilder = new ObjcProvider.Builder();
+    NestedSetBuilder<Artifact> applicationFilesToBuild = NestedSetBuilder.stableOrder();
+
+    // 1. Build watch extension bundle.
+    createWatchExtensionBundle(ruleContext);
+
+    // 2. Build watch application bundle, which will contain the extension bundle.
+    createWatchApplicationBundle(
+        ruleContext,
+        watchExtensionIpaArtifact(ruleContext),
+        applicationFilesToBuild,
+        exposedObjcProviderBuilder);
+
+    RuleConfiguredTargetBuilder targetBuilder =
+        ObjcRuleClasses.ruleConfiguredTarget(ruleContext, applicationFilesToBuild.build())
+            .addProvider(
+                InstrumentedFilesProvider.class,
+                InstrumentedFilesCollector.forward(ruleContext, "binary"));
+
+    // 3. Add final watch application artifacts to the ObjcProvider, for bundling the watch
+    // application bundle into the final iOS application IPA depending on this rule.
+    exposedObjcProviderBuilder.add(MERGE_ZIP, ruleContext.getImplicitOutputArtifact(APP_NAME_IPA));
+    WatchUtils.registerActionsToAddWatchSupport(
+        ruleContext, exposedObjcProviderBuilder, WatchOSVersion.OS2);
+    exposedObjcProviderBuilder.add(FLAG, HAS_WATCH2_EXTENSION);
+    targetBuilder.addProvider(ObjcProvider.class, exposedObjcProviderBuilder.build());
+
+    return targetBuilder.build();
+  }
+
+  /**
+   * Registers actions to create the watch extension bundle.
+   *
+   * @param ruleContext rule context in which to create the bundle
+   */
+  private void createWatchExtensionBundle(RuleContext ruleContext) throws InterruptedException {
+    new Watch2ExtensionSupport(
+            ruleContext,
+            ObjcRuleClasses.intermediateArtifacts(ruleContext),
+            watchExtensionBundleName(ruleContext))
+        .createBundle(watchExtensionIpaArtifact(ruleContext));
+  }
+
+  /**
+   * Registers actions to create the watch application bundle. This will contain the watch extension
+   * bundle. The output artifacts are {@link #APP_NAME_IPA} (which is an implicit output of this
+   * rule), and artifacts which are added to {@code exposedObjcProviderBuilder} for consumption by
+   * depending targets.
+   *
+   * @param ruleContext rule context in which to create the bundle
+   * @param filesToBuild the list to contain the files to be built for this bundle
+   * @param exposedObjcProviderBuilder builder of {@link ObjcProvider} exposed to the parent target;
+   *     bundling information will be added to this builder
+   */
+  private void createWatchApplicationBundle(
+      RuleContext ruleContext,
+      Artifact extensionIpa,
+      NestedSetBuilder<Artifact> filesToBuild,
+      ObjcProvider.Builder exposedObjcProviderBuilder)
+      throws InterruptedException {
+    new WatchApplicationSupport(
+            ruleContext,
+            WatchOSVersion.OS2,
+            // TODO(cparsons): Remove dependency attributes from WatchApplicationSupport,
+            // as this is redundant with other attributes.
+            ImmutableSet.<Attribute>of(),
+            new IntermediateArtifacts(ruleContext, "", watchApplicationBundleName(ruleContext)),
+            watchApplicationBundleName(ruleContext),
+            watchApplicationIpaArtifact(ruleContext),
+            watchApplicationBundleName(ruleContext))
+        .createBundle(ImmutableList.of(extensionIpa), filesToBuild, exposedObjcProviderBuilder);
+  }
+
+  /** Returns the {@Artifact} containing final watch application bundle. */
+  private Artifact watchApplicationIpaArtifact(RuleContext ruleContext)
+      throws InterruptedException {
+    return ruleContext.getImplicitOutputArtifact(APP_NAME_IPA);
+  }
+
+  /** Returns the {@Artifact} containing final watch extension bundle. */
+  private Artifact watchExtensionIpaArtifact(RuleContext ruleContext) throws InterruptedException {
+    return ruleContext.getImplicitOutputArtifact(ReleaseBundlingSupport.IPA);
+  }
+
+  private String watchApplicationBundleName(RuleContext ruleContext) {
+    return ruleContext.attributes().get(WATCH_APP_NAME_ATTR, Type.STRING);
+  }
+
+  private String watchExtensionBundleName(RuleContext ruleContext) {
+    return ruleContext.getLabel().getName();
+  }
+
+  private void validateAttributes(RuleContext ruleContext) throws RuleErrorException {
+    boolean hasError = false;
+
+    Multiset<Artifact> appResources = HashMultiset.create();
+    appResources.addAll(ruleContext.getPrerequisiteArtifacts("app_resources", Mode.TARGET).list());
+    appResources.addAll(ruleContext.getPrerequisiteArtifacts("app_strings", Mode.TARGET).list());
+
+    for (Multiset.Entry<Artifact> entry : appResources.entrySet()) {
+      if (entry.getCount() > 1) {
+        ruleContext.ruleError(
+            "The same file was included multiple times in this rule: "
+                + entry.getElement().getRootRelativePathString());
+        hasError = true;
+      }
+    }
+
+    Multiset<Artifact> extResources = HashMultiset.create();
+    extResources.addAll(ruleContext.getPrerequisiteArtifacts("ext_resources", Mode.TARGET).list());
+    extResources.addAll(ruleContext.getPrerequisiteArtifacts("ext_strings", Mode.TARGET).list());
+
+    for (Multiset.Entry<Artifact> entry : extResources.entrySet()) {
+      if (entry.getCount() > 1) {
+        ruleContext.ruleError(
+            "The same file was included multiple times in this rule: "
+                + entry.getElement().getRootRelativePathString());
+        hasError = true;
+      }
+    }
+
+    if (hasError) {
+      throw new RuleErrorException();
+    }
+  }
+}