Support robolectric_test

robolectric_test will compile a suite of tests that run in
robolectric.  For now it also generates a Run* rule, later
that will be removed in favor of atest.

Bug: 123248659
Test: m RunSettingsLibRoboTests
Change-Id: I12407d0b0d639e31c1969077ba787e8985e6a506

Android.bp

@@ -276,6 +276,7 @@ bootstrap_go_package {
         "java/plugin.go",
         "java/prebuilt_apis.go",
         "java/proto.go",
+        "java/robolectric.go",
         "java/sdk.go",
         "java/sdk_library.go",
         "java/support_libraries.go",

android/module.go

@@ -143,6 +143,7 @@ type ModuleContext interface {
 	OtherModuleErrorf(m blueprint.Module, fmt string, args ...interface{})
 	OtherModuleDependencyTag(m blueprint.Module) blueprint.DependencyTag
 
+	GetDirectDepsWithTag(tag blueprint.DependencyTag) []Module
 	GetDirectDepWithTag(name string, tag blueprint.DependencyTag) blueprint.Module
 	GetDirectDep(name string) (blueprint.Module, blueprint.DependencyTag)
 
@@ -1093,6 +1094,18 @@ func (a *androidModuleContext) getDirectDepInternal(name string, tag blueprint.D
 	}
 }
 
+func (a *androidModuleContext) GetDirectDepsWithTag(tag blueprint.DependencyTag) []Module {
+	var deps []Module
+	a.VisitDirectDepsBlueprint(func(m blueprint.Module) {
+		if aModule, _ := m.(Module); aModule != nil {
+			if a.ModuleContext.OtherModuleDependencyTag(aModule) == tag {
+				deps = append(deps, aModule)
+			}
+		}
+	})
+	return deps
+}
+
 func (a *androidModuleContext) GetDirectDepWithTag(name string, tag blueprint.DependencyTag) blueprint.Module {
 	m, _ := a.getDirectDepInternal(name, tag)
 	return m

java/robolectric.go

@@ -0,0 +1,110 @@
+// Copyright 2019 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 java
+
+import (
+	"fmt"
+	"io"
+	"strings"
+
+	"android/soong/android"
+)
+
+func init() {
+	android.RegisterModuleType("android_robolectric_test", RobolectricTestFactory)
+}
+
+var robolectricDefaultLibs = []string{
+	"robolectric_android-all-stub",
+	"Robolectric_all-target",
+	"mockito-robolectric-prebuilt",
+	"truth-prebuilt",
+}
+
+type robolectricProperties struct {
+	// The name of the android_app module that the tests will run against.
+	Instrumentation_for *string
+
+	Test_options struct {
+		// Timeout in seconds when running the tests.
+		Timeout *string
+	}
+}
+
+type robolectricTest struct {
+	Library
+
+	robolectricProperties robolectricProperties
+
+	libs []string
+}
+
+func (r *robolectricTest) DepsMutator(ctx android.BottomUpMutatorContext) {
+	r.Library.DepsMutator(ctx)
+
+	if r.robolectricProperties.Instrumentation_for != nil {
+		ctx.AddVariationDependencies(nil, instrumentationForTag, String(r.robolectricProperties.Instrumentation_for))
+	} else {
+		ctx.PropertyErrorf("instrumentation_for", "missing required instrumented module")
+	}
+
+	ctx.AddVariationDependencies(nil, libTag, robolectricDefaultLibs...)
+}
+
+func (r *robolectricTest) GenerateAndroidBuildActions(ctx android.ModuleContext) {
+	r.Library.GenerateAndroidBuildActions(ctx)
+
+	for _, dep := range ctx.GetDirectDepsWithTag(libTag) {
+		r.libs = append(r.libs, ctx.OtherModuleName(dep))
+	}
+}
+
+func (r *robolectricTest) AndroidMk() android.AndroidMkData {
+	data := r.Library.AndroidMk()
+
+	data.Custom = func(w io.Writer, name, prefix, moduleDir string, data android.AndroidMkData) {
+		android.WriteAndroidMkData(w, data)
+
+		fmt.Fprintln(w, "")
+		fmt.Fprintln(w, "include $(CLEAR_VARS)")
+		fmt.Fprintln(w, "LOCAL_MODULE := Run"+name)
+		fmt.Fprintln(w, "LOCAL_JAVA_LIBRARIES :=", name)
+		fmt.Fprintln(w, "LOCAL_JAVA_LIBRARIES += ", strings.Join(r.libs, " "))
+		fmt.Fprintln(w, "LOCAL_TEST_PACKAGE :=", String(r.robolectricProperties.Instrumentation_for))
+		if t := r.robolectricProperties.Test_options.Timeout; t != nil {
+			fmt.Fprintln(w, "LOCAL_ROBOTEST_TIMEOUT :=", *t)
+		}
+		fmt.Fprintln(w, "-include external/robolectric-shadows/run_robotests.mk")
+	}
+
+	return data
+}
+
+// An android_robolectric_test module compiles tests against the Robolectric framework that can run on the local host
+// instead of on a device.  It also generates a rule with the name of the module prefixed with "Run" that can be
+// used to run the tests.  Running the tests with build rule will eventually be deprecated and replaced with atest.
+func RobolectricTestFactory() android.Module {
+	module := &robolectricTest{}
+
+	module.AddProperties(
+		&module.Module.properties,
+		&module.Module.protoProperties,
+		&module.robolectricProperties)
+
+	module.Module.dexpreopter.isTest = true
+
+	InitJavaModule(module, android.DeviceSupported)
+	return module
+}