support-additional_providers-in-make_rule

rules/android_library/rule.bzl

@@ -140,14 +140,16 @@ def make_rule(
         attrs = _ATTRS,
         implementation = _impl,
         outputs = _outputs,
-        additional_toolchains = []):
+        additional_toolchains = [],
+        additional_providers = []):
     """Makes the rule.
 
     Args:
       attrs: A dict. The attributes for the rule.
       implementation: A function. The rule's implementation method.
       outputs: A dict, function, or None. The rule's outputs.
       additional_toolchains: A list. Additional toolchains passed to pass to rule(toolchains).
+      additional_providers: A list. Additional providers passed to pass to rule(providers).
 
     Returns:
       A rule.
@@ -167,7 +169,7 @@ def make_rule(
             AndroidLibraryResourceClassJarProvider,
             AndroidNativeLibsInfo,
             JavaInfo,
-        ],
+        ] + additional_providers,
         outputs = outputs,
         toolchains = [
             "//toolchains/android:toolchain_type",

test/rules/android_library/BUILD

@@ -0,0 +1,23 @@
+load(":custom_android_library.bzl", "custom_android_library")
+load(":test.bzl", "custom_android_library_test")
+load("@bazel_skylib//:bzl_library.bzl", "bzl_library")
+
+licenses(["notice"])
+
+custom_android_library(
+    name = "custom_android_library",
+    testonly = True,
+    key = "test_key",
+)
+
+custom_android_library_test(
+    name = "custom_android_library_test",
+    lib = ":custom_android_library",
+)
+
+test_suite(
+    name = "integration_tests",
+    tests = [
+        ":custom_android_library_test",
+    ],
+)

test/rules/android_library/custom_android_library.bzl

@@ -0,0 +1,83 @@
+# 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.
+load(
+    "//rules:attrs.bzl",
+    _attrs = "attrs",
+)
+load(
+    "//rules/android_library:rule.bzl",
+    _make_rule = "make_rule",
+)
+load(
+    "//rules/android_library:attrs.bzl",
+    _BASE_ATTRS = "ATTRS",
+)
+load(
+    "//rules:java.bzl",
+    _java = "java",
+)
+load(
+    "//rules:processing_pipeline.bzl",
+    _ProviderInfo = "ProviderInfo",
+    _processing_pipeline = "processing_pipeline",
+)
+load(
+    "//rules/android_library:impl.bzl",
+    _BASE_PROCESSORS = "PROCESSORS",
+    _finalize = "finalize",
+)
+
+CustomProvider = provider(
+    doc = "Custom provider to provide",
+    fields = dict(
+        key = "Some key to provide",
+    ),
+)
+
+def _process_custom_provider(ctx, **unused_sub_ctxs):
+    return _ProviderInfo(
+        name = "custom_provider_ctx",
+        value = struct(
+            providers = [
+                CustomProvider(
+                    key = ctx.attr.key,
+                ),
+            ],
+        ),
+    )
+
+PROCESSORS = _processing_pipeline.append(
+    _BASE_PROCESSORS,
+    CustomProviderProcessor = _process_custom_provider,
+)
+
+_PROCESSING_PIPELINE = _processing_pipeline.make_processing_pipeline(
+    processors = PROCESSORS,
+    finalize = _finalize,
+)
+
+def _impl(ctx):
+    java_package = _java.resolve_package_from_label(ctx.label, ctx.attr.custom_package)
+    return _processing_pipeline.run(ctx, java_package, _PROCESSING_PIPELINE)
+
+custom_android_library = _make_rule(
+    implementation = _impl,
+    attrs = _attrs.add(_BASE_ATTRS, dict(
+        # Custom attribute to wrap in a provider
+        key = attr.string(),
+    )),
+    additional_providers = [
+        CustomProvider,
+    ],
+)

test/rules/android_library/test.bzl

@@ -0,0 +1,25 @@
+load(
+    "//test/utils:lib.bzl",
+    "asserts",
+    "unittest",
+)
+load(
+    ":custom_android_library.bzl",
+    "CustomProvider",
+)
+
+def custom_android_library_test_impl(ctx):
+    env = unittest.begin(ctx)
+
+    # Assert that the custom provider exists
+    asserts.true(env, CustomProvider in ctx.attr.lib)
+    asserts.equals(env, ctx.attr.lib[CustomProvider].key, "test_key")
+
+    return unittest.end(env)
+
+custom_android_library_test = unittest.make(
+    impl = custom_android_library_test_impl,
+    attrs = {
+        "lib": attr.label(providers = [CustomProvider]),
+    },
+)