Expose mergeManifests method in Skylark

RELNOTES: none
PiperOrigin-RevId: 190253911

1 files changed, 103 insertions, 0 deletions

diff --git a/src/main/java/com/google/devtools/build/lib/rules/android/AndroidSkylarkData.java b/src/main/java/com/google/devtools/build/lib/rules/android/AndroidSkylarkData.java
new file mode 100644
index 0000000000..b7cc005a8b
--- /dev/null
+++ b/src/main/java/com/google/devtools/build/lib/rules/android/AndroidSkylarkData.java
@@ -0,0 +1,103 @@
+// 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.rules.android;
+
+import com.google.devtools.build.lib.actions.Artifact;
+import com.google.devtools.build.lib.analysis.ConfiguredTarget;
+import com.google.devtools.build.lib.analysis.skylark.SkylarkRuleContext;
+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.Runtime;
+import com.google.devtools.build.lib.syntax.SkylarkList;
+import javax.annotation.Nullable;
+
+/** Skylark-visible methods for working with Android data (manifests, resources, and assets). */
+@SkylarkModule(
+  name = "android_data",
+  doc = "Utilities for working with Android data (manifests, resources, and assets)"
+)
+public class AndroidSkylarkData {
+  @SkylarkCallable(
+    name = "merge_manifests",
+    mandatoryPositionals = 1, // context is mandatory
+    parameters = {
+      @Param(
+        name = "manifest",
+        positional = false,
+        defaultValue = "None",
+        type = Artifact.class,
+        noneable = true,
+        named = true,
+        doc = "This target's manifest. Optional."
+      ),
+      @Param(
+        name = "deps",
+        positional = false,
+        defaultValue = "[]",
+        type = SkylarkList.class,
+        generic1 = ConfiguredTarget.class,
+        named = true,
+        doc =
+            "Targets from which this dependency should inherit manifests (if they are provided)."
+                + " Optional."
+      ),
+      @Param(
+        name = "custom_package",
+        positional = false,
+        defaultValue = "None",
+        type = String.class,
+        noneable = true,
+        named = true,
+        doc =
+            "If passed, the manifest will be stamped with this package. Otherwise, the manifest"
+                + " will be stamped with a package based on the current Java package."
+      )
+    },
+    doc = "Merges manifests from this target and dependencies, and returns a manifest provider."
+  )
+  public AndroidManifestInfo mergeManifests(
+      SkylarkRuleContext ctx,
+      Object manifest,
+      SkylarkList<ConfiguredTarget> deps,
+      Object customPackage)
+      throws InterruptedException {
+    return AndroidManifest.of(
+            ctx.getRuleContext(),
+            fromNoneable(Artifact.class, manifest),
+            fromNoneable(String.class, customPackage))
+        .stampAndMergeWith(deps.getImmutableList())
+        .toProvider();
+  }
+
+  /**
+   * Converts a "Noneable" Object passed by Skylark to the appropriate type or null.
+   *
+   * <p>Skylark "Noneable" types are passed in as an Object that may be either the correct type or a
+   * Runtime.NONE object. Skylark will handle type checking, based on the appropriate @param
+   * annotation, but we still need to do the actual cast (or conversion to null) ourselves.
+   *
+   * @param clazz the correct class, as defined in the @Param annotation
+   * @param noneable the Noneable object
+   * @param <T> the type to cast to
+   * @return null, if the noneable argument was None, or the cast object, otherwise.
+   */
+  private static @Nullable <T> T fromNoneable(Class<T> clazz, Object noneable) {
+    if (noneable == Runtime.NONE) {
+      return null;
+    }
+
+    return clazz.cast(noneable);
+  }
+}