Add support for android_test modules

android_test module are APKs that can be run as tests, either
as standalone unit tests or as instrumentation tests for another
APK.

Test: m checkbuild
Change-Id: I16661701637e4048fd99442029c3e195ebf373a4
diff --git a/java/androidmk.go b/java/androidmk.go
index 88dc6ef..bc9544a 100644
--- a/java/androidmk.go
+++ b/java/androidmk.go
@@ -228,6 +228,19 @@
 	}
 }
 
+func (a *AndroidTest) AndroidMk() android.AndroidMkData {
+	data := a.AndroidApp.AndroidMk()
+	data.Extra = append(data.Extra, func(w io.Writer, outputFile android.Path) {
+		fmt.Fprintln(w, "LOCAL_MODULE_TAGS := tests")
+		if len(a.testProperties.Test_suites) > 0 {
+			fmt.Fprintln(w, "LOCAL_COMPATIBILITY_SUITE :=",
+				strings.Join(a.testProperties.Test_suites, " "))
+		}
+	})
+
+	return data
+}
+
 func (a *AndroidLibrary) AndroidMk() android.AndroidMkData {
 	data := a.Library.AndroidMk()
 
diff --git a/java/app.go b/java/app.go
index ae0592a..37109b5 100644
--- a/java/app.go
+++ b/java/app.go
@@ -26,6 +26,7 @@
 
 func init() {
 	android.RegisterModuleType("android_app", AndroidAppFactory)
+	android.RegisterModuleType("android_test", AndroidTestFactory)
 }
 
 // AndroidManifest.xml merging
@@ -50,8 +51,6 @@
 
 	// list of resource labels to generate individual resource packages
 	Package_splits []string
-
-	Instrumentation_for *string
 }
 
 type AndroidApp struct {
@@ -61,6 +60,8 @@
 	certificate certificate
 
 	appProperties appProperties
+
+	extraLinkFlags []string
 }
 
 func (a *AndroidApp) ExportedProguardFlagFiles() android.Paths {
@@ -85,14 +86,11 @@
 }
 
 func (a *AndroidApp) GenerateAndroidBuildActions(ctx android.ModuleContext) {
-	var linkFlags []string
-	if String(a.appProperties.Instrumentation_for) != "" {
-		linkFlags = append(linkFlags,
-			"--rename-instrumentation-target-package",
-			String(a.appProperties.Instrumentation_for))
-	} else {
-		a.properties.Instrument = true
-	}
+	a.generateAndroidBuildActions(ctx)
+}
+
+func (a *AndroidApp) generateAndroidBuildActions(ctx android.ModuleContext) {
+	linkFlags := append([]string(nil), a.extraLinkFlags...)
 
 	hasProduct := false
 	for _, f := range a.aaptProperties.Aaptflags {
@@ -188,6 +186,8 @@
 	module.Module.deviceProperties.Optimize.Enabled = proptools.BoolPtr(true)
 	module.Module.deviceProperties.Optimize.Shrink = proptools.BoolPtr(true)
 
+	module.Module.properties.Instrument = true
+
 	module.AddProperties(
 		&module.Module.properties,
 		&module.Module.deviceProperties,
@@ -198,3 +198,43 @@
 	android.InitAndroidArchModule(module, android.DeviceSupported, android.MultilibCommon)
 	return module
 }
+
+type appTestProperties struct {
+	Instrumentation_for *string
+}
+
+type AndroidTest struct {
+	AndroidApp
+
+	appTestProperties appTestProperties
+
+	testProperties testProperties
+}
+
+func (a *AndroidTest) GenerateAndroidBuildActions(ctx android.ModuleContext) {
+	if String(a.appTestProperties.Instrumentation_for) != "" {
+		a.AndroidApp.extraLinkFlags = append(a.AndroidApp.extraLinkFlags,
+			"--rename-instrumentation-target-package",
+			String(a.appTestProperties.Instrumentation_for))
+	}
+
+	a.generateAndroidBuildActions(ctx)
+}
+
+func AndroidTestFactory() android.Module {
+	module := &AndroidTest{}
+
+	module.Module.deviceProperties.Optimize.Enabled = proptools.BoolPtr(true)
+
+	module.AddProperties(
+		&module.Module.properties,
+		&module.Module.deviceProperties,
+		&module.Module.protoProperties,
+		&module.aaptProperties,
+		&module.appProperties,
+		&module.appTestProperties)
+
+	android.InitAndroidArchModule(module, android.DeviceSupported, android.MultilibCommon)
+
+	return module
+}
diff --git a/java/java.go b/java/java.go
index a4cb65b..02fdc00 100644
--- a/java/java.go
+++ b/java/java.go
@@ -212,8 +212,8 @@
 	}
 
 	Optimize struct {
-		// If false, disable all optimization.  Defaults to true for apps, false for
-		// libraries and tests.
+		// If false, disable all optimization.  Defaults to true for android_app and android_test
+		// modules, false for java_library and java_test modules.
 		Enabled *bool
 
 		// If true, optimize for size by removing unused code.  Defaults to true for apps,