Add dependencies from platform_bootclasspath to contents

Adds a FinalDeps mutator to add dependencies from the
platform_bootclasspath to the configured boot jars which can be from
either the platform or any apex. It adds dependencies for every
configured boot jar, whether in ArtApexJars, BootJars or
UpdatableBootJars.

At the moment the dependencies are only used for testing purposes
but following changes will make more use of them.

Bug: 177892522
Test: m nothing
Change-Id: I981305bf45bc20539a3d36987252f490e2b885cc

3 files changed, 222 insertions, 3 deletions

diff --git a/java/platform_bootclasspath.go b/java/platform_bootclasspath.go
index 550707754..5272eaf77 100644
--- a/java/platform_bootclasspath.go
+++ b/java/platform_bootclasspath.go
@@ -17,6 +17,7 @@ package java
 import (
 	"android/soong/android"
 	"android/soong/dexpreopt"
+	"github.com/google/blueprint"
 )
 
 func init() {
@@ -25,10 +26,38 @@ func init() {
 
 func registerPlatformBootclasspathBuildComponents(ctx android.RegistrationContext) {
 	ctx.RegisterModuleType("platform_bootclasspath", platformBootclasspathFactory)
+
+	ctx.FinalDepsMutators(func(ctx android.RegisterMutatorsContext) {
+		ctx.BottomUp("platform_bootclasspath_deps", platformBootclasspathDepsMutator)
+	})
+}
+
+type platformBootclasspathDependencyTag struct {
+	blueprint.BaseDependencyTag
+
+	name string
 }
 
+// Avoid having to make platform bootclasspath content visible to the platform bootclasspath.
+//
+// This is a temporary workaround to make it easier to migrate to platform bootclasspath with proper
+// dependencies.
+// TODO(b/177892522): Remove this and add needed visibility.
+func (t platformBootclasspathDependencyTag) ExcludeFromVisibilityEnforcement() {
+}
+
+// The tag used for the dependency between the platform bootclasspath and any configured boot jars.
+var platformBootclasspathModuleDepTag = platformBootclasspathDependencyTag{name: "module"}
+
+var _ android.ExcludeFromVisibilityEnforcementTag = platformBootclasspathDependencyTag{}
+
 type platformBootclasspathModule struct {
 	android.ModuleBase
+
+	// The apex:module pairs obtained from the configured modules.
+	//
+	// Currently only for testing.
+	configuredModules []android.Module
 }
 
 func platformBootclasspathFactory() android.Module {
@@ -47,7 +76,71 @@ func (b *platformBootclasspathModule) DepsMutator(ctx android.BottomUpMutatorCon
 	dexpreopt.RegisterToolDeps(ctx)
 }
 
+func platformBootclasspathDepsMutator(ctx android.BottomUpMutatorContext) {
+	m := ctx.Module()
+	if p, ok := m.(*platformBootclasspathModule); ok {
+		// Add dependencies on all the modules configured in the "art" boot image.
+		artImageConfig := genBootImageConfigs(ctx)[artBootImageName]
+		addDependenciesOntoBootImageModules(ctx, artImageConfig.modules)
+
+		// Add dependencies on all the modules configured in the "boot" boot image. That does not
+		// include modules configured in the "art" boot image.
+		bootImageConfig := p.getImageConfig(ctx)
+		addDependenciesOntoBootImageModules(ctx, bootImageConfig.modules)
+
+		// Add dependencies on all the updatable modules.
+		updatableModules := dexpreopt.GetGlobalConfig(ctx).UpdatableBootJars
+		addDependenciesOntoBootImageModules(ctx, updatableModules)
+	}
+}
+
+func addDependencyOntoApexModulePair(ctx android.BottomUpMutatorContext, apex string, name string, tag blueprint.DependencyTag) {
+	var variations []blueprint.Variation
+	if apex != "platform" {
+		// Pick the correct apex variant.
+		variations = []blueprint.Variation{
+			{Mutator: "apex", Variation: apex},
+		}
+	}
+
+	addedDep := false
+	if ctx.OtherModuleDependencyVariantExists(variations, name) {
+		ctx.AddFarVariationDependencies(variations, tag, name)
+		addedDep = true
+	}
+
+	// Add a dependency on the prebuilt module if it exists.
+	prebuiltName := android.PrebuiltNameFromSource(name)
+	if ctx.OtherModuleDependencyVariantExists(variations, prebuiltName) {
+		ctx.AddVariationDependencies(variations, tag, prebuiltName)
+		addedDep = true
+	}
+
+	// If no appropriate variant existing for this, so no dependency could be added, then it is an
+	// error, unless missing dependencies are allowed. The simplest way to handle that is to add a
+	// dependency that will not be satisfied and the default behavior will handle it.
+	if !addedDep {
+		ctx.AddFarVariationDependencies(variations, tag, name)
+	}
+}
+
+func addDependenciesOntoBootImageModules(ctx android.BottomUpMutatorContext, modules android.ConfiguredJarList) {
+	for i := 0; i < modules.Len(); i++ {
+		apex := modules.Apex(i)
+		name := modules.Jar(i)
+
+		addDependencyOntoApexModulePair(ctx, apex, name, platformBootclasspathModuleDepTag)
+	}
+}
+
 func (b *platformBootclasspathModule) GenerateAndroidBuildActions(ctx android.ModuleContext) {
+	ctx.VisitDirectDepsIf(isActiveModule, func(module android.Module) {
+		tag := ctx.OtherModuleDependencyTag(module)
+		if tag == platformBootclasspathModuleDepTag {
+			b.configuredModules = append(b.configuredModules, module)
+		}
+	})
+
 	// Nothing to do if skipping the dexpreopt of boot image jars.
 	if SkipDexpreoptBootJars(ctx) {
 		return
diff --git a/java/platform_bootclasspath_test.go b/java/platform_bootclasspath_test.go
index 1c81cfdc2..ebbe3a5ee 100644
--- a/java/platform_bootclasspath_test.go
+++ b/java/platform_bootclasspath_test.go
@@ -29,10 +29,105 @@ var prepareForTestWithPlatformBootclasspath = android.GroupFixturePreparers(
 )
 
 func TestPlatformBootclasspath(t *testing.T) {
-	prepareForTestWithPlatformBootclasspath.
-		RunTestWithBp(t, `
+	preparer := android.GroupFixturePreparers(
+		prepareForTestWithPlatformBootclasspath,
+		dexpreopt.FixtureSetBootJars("platform:foo", "platform:bar"),
+		android.FixtureWithRootAndroidBp(`
 			platform_bootclasspath {
 				name: "platform-bootclasspath",
 			}
-		`)
+
+			java_library {
+				name: "bar",
+				srcs: ["a.java"],
+				system_modules: "none",
+				sdk_version: "none",
+				compile_dex: true,
+			}
+		`),
+	)
+
+	var addSourceBootclassPathModule = android.FixtureAddTextFile("source/Android.bp", `
+		java_library {
+			name: "foo",
+			srcs: ["a.java"],
+			system_modules: "none",
+			sdk_version: "none",
+			compile_dex: true,
+		}
+	`)
+
+	var addPrebuiltBootclassPathModule = android.FixtureAddTextFile("prebuilt/Android.bp", `
+		java_import {
+			name: "foo",
+			jars: ["a.jar"],
+			compile_dex: true,
+			prefer: false,
+		}
+	`)
+
+	var addPrebuiltPreferredBootclassPathModule = android.FixtureAddTextFile("prebuilt/Android.bp", `
+		java_import {
+			name: "foo",
+			jars: ["a.jar"],
+			compile_dex: true,
+			prefer: true,
+		}
+	`)
+
+	t.Run("missing", func(t *testing.T) {
+		preparer.
+			ExtendWithErrorHandler(android.FixtureExpectsAtLeastOneErrorMatchingPattern(`"platform-bootclasspath" depends on undefined module "foo"`)).
+			RunTest(t)
+	})
+
+	t.Run("source", func(t *testing.T) {
+		result := android.GroupFixturePreparers(
+			preparer,
+			addSourceBootclassPathModule,
+		).RunTest(t)
+
+		CheckPlatformBootclasspathModules(t, result, "platform-bootclasspath", []string{
+			"platform:foo",
+			"platform:bar",
+		})
+	})
+
+	t.Run("prebuilt", func(t *testing.T) {
+		result := android.GroupFixturePreparers(
+			preparer,
+			addPrebuiltBootclassPathModule,
+		).RunTest(t)
+
+		CheckPlatformBootclasspathModules(t, result, "platform-bootclasspath", []string{
+			"platform:prebuilt_foo",
+			"platform:bar",
+		})
+	})
+
+	t.Run("source+prebuilt - source preferred", func(t *testing.T) {
+		result := android.GroupFixturePreparers(
+			preparer,
+			addSourceBootclassPathModule,
+			addPrebuiltBootclassPathModule,
+		).RunTest(t)
+
+		CheckPlatformBootclasspathModules(t, result, "platform-bootclasspath", []string{
+			"platform:foo",
+			"platform:bar",
+		})
+	})
+
+	t.Run("source+prebuilt - prebuilt preferred", func(t *testing.T) {
+		result := android.GroupFixturePreparers(
+			preparer,
+			addSourceBootclassPathModule,
+			addPrebuiltPreferredBootclassPathModule,
+		).RunTest(t)
+
+		CheckPlatformBootclasspathModules(t, result, "platform-bootclasspath", []string{
+			"platform:prebuilt_foo",
+			"platform:bar",
+		})
+	})
 }
diff --git a/java/testing.go b/java/testing.go
index 80c107d12..455cca9dd 100644
--- a/java/testing.go
+++ b/java/testing.go
@@ -300,6 +300,37 @@ func CheckModuleDependencies(t *testing.T, ctx *android.TestContext, name, varia
 	}
 }
 
+// CheckPlatformBootclasspathModules returns the apex:module pair for the modules depended upon by
+// the platform-bootclasspath module.
+func CheckPlatformBootclasspathModules(t *testing.T, result *android.TestResult, name string, expected []string) {
+	t.Helper()
+	platformBootclasspath := result.Module(name, "android_common").(*platformBootclasspathModule)
+	pairs := ApexNamePairsFromModules(result.TestContext, platformBootclasspath.configuredModules)
+	android.AssertDeepEquals(t, fmt.Sprintf("%s modules", "platform-bootclasspath"), expected, pairs)
+}
+
+// ApexNamePairsFromModules returns the apex:module pair for the supplied modules.
+func ApexNamePairsFromModules(ctx *android.TestContext, modules []android.Module) []string {
+	pairs := []string{}
+	for _, module := range modules {
+		pairs = append(pairs, apexNamePairFromModule(ctx, module))
+	}
+	return pairs
+}
+
+func apexNamePairFromModule(ctx *android.TestContext, module android.Module) string {
+	name := module.Name()
+	var apex string
+	apexInfo := ctx.ModuleProvider(module, android.ApexInfoProvider).(android.ApexInfo)
+	if apexInfo.IsForPlatform() {
+		apex = "platform"
+	} else {
+		apex = apexInfo.InApexes[0]
+	}
+
+	return fmt.Sprintf("%s:%s", apex, name)
+}
+
 func CheckHiddenAPIRuleInputs(t *testing.T, expected string, hiddenAPIRule android.TestingBuildParams) {
 	t.Helper()
 	actual := strings.TrimSpace(strings.Join(android.NormalizePathsForTesting(hiddenAPIRule.Implicits), "\n"))