Add integration testing infrastructure

Fix mutator registration for tests to allow different tests
in the same package to register different mutators.

Allow tests to track the resulting ModuleBuildParams objects
to use in assertions, and provide helpers for getting them.
For example:
    config := android.TestConfig(buildDir)
    ctx := android.NewTestContext()
    ctx.RegisterModuleType(...)
    ctx.MockFileSystem(...)
    ctx.ParseBlueprintsFile("Android.bp")
    ctx.PrepareBuildActions(config)
    ctx.Register()
    // Get the Inputs value passed to the javac rule for the foo module
    inputs := ctx.ModuleForTests("foo".Rule("javac").Inputs

Test: java_test.go
Change-Id: I10c82967f5f3586d2c176f169906b571ed82fc73

Android.bp

@@ -51,6 +51,7 @@ bootstrap_go_package {
         "android/paths.go",
         "android/prebuilt.go",
         "android/register.go",
+        "android/testing.go",
         "android/util.go",
         "android/variable.go",
 

android/config.go

@@ -84,6 +84,8 @@ type config struct {
 
 	inMake bool
 
+	captureBuild bool // true for tests, saves build parameters for each module
+
 	OncePer
 }
 
@@ -171,7 +173,8 @@ func TestConfig(buildDir string) Config {
 			DeviceName: stringPtr("test_device"),
 		},
 
-		buildDir: buildDir,
+		buildDir:     buildDir,
+		captureBuild: true,
 	}
 	config.deviceConfig = &deviceConfig{
 		config: config,

android/defaults.go

@@ -113,6 +113,11 @@ func (defaultable *DefaultableModule) applyDefaults(ctx TopDownMutatorContext,
 	}
 }
 
+func registerDefaultsPreArchMutators(ctx RegisterMutatorsContext) {
+	ctx.BottomUp("defaults_deps", defaultsDepsMutator).Parallel()
+	ctx.TopDown("defaults", defaultsMutator).Parallel()
+}
+
 func defaultsDepsMutator(ctx BottomUpMutatorContext) {
 	if defaultable, ok := ctx.Module().(Defaultable); ok {
 		ctx.AddDependency(ctx.Module(), DefaultsDepTag, defaultable.defaults().Defaults...)

android/module.go

@@ -111,6 +111,8 @@ type Module interface {
 
 	AddProperties(props ...interface{})
 	GetProperties() []interface{}
+
+	BuildParamsForTests() []ModuleBuildParams
 }
 
 type nameProperties struct {
@@ -291,6 +293,9 @@ type ModuleBase struct {
 	hooks hooks
 
 	registerProps []interface{}
+
+	// For tests
+	buildParams []ModuleBuildParams
 }
 
 func (a *ModuleBase) AddProperties(props ...interface{}) {
@@ -301,6 +306,10 @@ func (a *ModuleBase) GetProperties() []interface{} {
 	return a.registerProps
 }
 
+func (a *ModuleBase) BuildParamsForTests() []ModuleBuildParams {
+	return a.buildParams
+}
+
 // Name returns the name of the module.  It may be overridden by individual module types, for
 // example prebuilts will prepend prebuilt_ to the name.
 func (a *ModuleBase) Name() string {
@@ -520,6 +529,8 @@ func (a *ModuleBase) GenerateBuildActions(ctx blueprint.ModuleContext) {
 			return
 		}
 	}
+
+	a.buildParams = androidCtx.buildParams
 }
 
 type androidBaseContextImpl struct {
@@ -538,6 +549,9 @@ type androidModuleContext struct {
 	checkbuildFiles Paths
 	missingDeps     []string
 	module          Module
+
+	// For tests
+	buildParams []ModuleBuildParams
 }
 
 func (a *androidModuleContext) ninjaError(desc string, outputs []string, err error) {
@@ -566,6 +580,10 @@ func (a *androidModuleContext) Build(pctx blueprint.PackageContext, params bluep
 }
 
 func (a *androidModuleContext) ModuleBuild(pctx blueprint.PackageContext, params ModuleBuildParams) {
+	if a.config.captureBuild {
+		a.buildParams = append(a.buildParams, params)
+	}
+
 	bparams := blueprint.BuildParams{
 		Rule:            params.Rule,
 		Deps:            params.Deps,

android/mutator.go

@@ -15,8 +15,6 @@
 package android
 
 import (
-	"sync"
-
 	"github.com/google/blueprint"
 )
 
@@ -27,9 +25,6 @@ import (
 //   Deps
 //   PostDeps
 
-var registerMutatorsOnce sync.Once
-var registeredMutators []*mutator
-
 func registerMutatorsToContext(ctx *blueprint.Context, mutators []*mutator) {
 	for _, t := range mutators {
 		var handle blueprint.MutatorHandle
@@ -44,56 +39,24 @@ func registerMutatorsToContext(ctx *blueprint.Context, mutators []*mutator) {
 	}
 }
 
-func registerMutators(ctx *blueprint.Context) {
+func registerMutators(ctx *blueprint.Context, preArch, preDeps, postDeps []RegisterMutatorFunc) {
-
+	mctx := &registerMutatorsContext{}
-	registerMutatorsOnce.Do(func() {
-		ctx := &registerMutatorsContext{}
-
-		register := func(funcs []RegisterMutatorFunc) {
-			for _, f := range funcs {
-				f(ctx)
-			}
-		}
-
-		ctx.TopDown("load_hooks", loadHookMutator).Parallel()
-		ctx.BottomUp("prebuilts", prebuiltMutator).Parallel()
-		ctx.BottomUp("defaults_deps", defaultsDepsMutator).Parallel()
-		ctx.TopDown("defaults", defaultsMutator).Parallel()
-
-		register(preArch)
-
-		ctx.BottomUp("arch", archMutator).Parallel()
-		ctx.TopDown("arch_hooks", archHookMutator).Parallel()
-
-		register(preDeps)
-
-		ctx.BottomUp("deps", depsMutator).Parallel()
-
-		ctx.TopDown("prebuilt_select", PrebuiltSelectModuleMutator).Parallel()
-		ctx.BottomUp("prebuilt_replace", PrebuiltReplaceMutator).Parallel()
-
-		register(postDeps)
-
-		registeredMutators = ctx.mutators
-	})
-
-	registerMutatorsToContext(ctx, registeredMutators)
-}
-
-func RegisterTestMutators(ctx *blueprint.Context) {
-	mutators := &registerMutatorsContext{}
 
 	register := func(funcs []RegisterMutatorFunc) {
 		for _, f := range funcs {
-			f(mutators)
+			f(mctx)
 		}
 	}
 
-	register(testPreDeps)
+	register(preArch)
-	mutators.BottomUp("deps", depsMutator).Parallel()
-	register(testPostDeps)
 
-	registerMutatorsToContext(ctx, mutators.mutators)
+	register(preDeps)
+
+	mctx.BottomUp("deps", depsMutator).Parallel()
+
+	register(postDeps)
+
+	registerMutatorsToContext(ctx, mctx.mutators)
 }
 
 type registerMutatorsContext struct {
@@ -107,7 +70,24 @@ type RegisterMutatorsContext interface {
 
 type RegisterMutatorFunc func(RegisterMutatorsContext)
 
-var preArch, preDeps, postDeps, testPreDeps, testPostDeps []RegisterMutatorFunc
+var preArch = []RegisterMutatorFunc{
+	func(ctx RegisterMutatorsContext) {
+		ctx.TopDown("load_hooks", loadHookMutator).Parallel()
+	},
+	registerPrebuiltsPreArchMutators,
+	registerDefaultsPreArchMutators,
+}
+
+var preDeps = []RegisterMutatorFunc{
+	func(ctx RegisterMutatorsContext) {
+		ctx.BottomUp("arch", archMutator).Parallel()
+		ctx.TopDown("arch_hooks", archHookMutator).Parallel()
+	},
+}
+
+var postDeps = []RegisterMutatorFunc{
+	registerPrebuiltsPostDepsMutators,
+}
 
 func PreArchMutators(f RegisterMutatorFunc) {
 	preArch = append(preArch, f)
@@ -121,14 +101,6 @@ func PostDepsMutators(f RegisterMutatorFunc) {
 	postDeps = append(postDeps, f)
 }
 
-func TestPreDepsMutators(f RegisterMutatorFunc) {
-	testPreDeps = append(testPreDeps, f)
-}
-
-func TeststPostDepsMutators(f RegisterMutatorFunc) {
-	testPostDeps = append(testPostDeps, f)
-}
-
 type AndroidTopDownMutator func(TopDownMutatorContext)
 
 type TopDownMutatorContext interface {

android/prebuilt.go

@@ -61,6 +61,15 @@ type PrebuiltInterface interface {
 	Prebuilt() *Prebuilt
 }
 
+func registerPrebuiltsPreArchMutators(ctx RegisterMutatorsContext) {
+	ctx.BottomUp("prebuilts", prebuiltMutator).Parallel()
+}
+
+func registerPrebuiltsPostDepsMutators(ctx RegisterMutatorsContext) {
+	ctx.TopDown("prebuilt_select", PrebuiltSelectModuleMutator).Parallel()
+	ctx.BottomUp("prebuilt_replace", PrebuiltReplaceMutator).Parallel()
+}
+
 // prebuiltMutator ensures that there is always a module with an undecorated name, and marks
 // prebuilt modules that have both a prebuilt and a source module.
 func prebuiltMutator(ctx BottomUpMutatorContext) {

android/prebuilt_test.go

@@ -122,9 +122,12 @@ func TestPrebuilts(t *testing.T) {
 
 	for _, test := range prebuiltsTests {
 		t.Run(test.name, func(t *testing.T) {
-			ctx := NewContext()
+			ctx := NewTestContext()
+			ctx.PreArchMutators(registerPrebuiltsPreArchMutators)
+			ctx.PostDepsMutators(registerPrebuiltsPostDepsMutators)
 			ctx.RegisterModuleType("prebuilt", ModuleFactoryAdaptor(newPrebuiltModule))
 			ctx.RegisterModuleType("source", ModuleFactoryAdaptor(newSourceModule))
+			ctx.Register()
 			ctx.MockFileSystem(map[string][]byte{
 				"Blueprints": []byte(`
 					source {
@@ -139,13 +142,10 @@ func TestPrebuilts(t *testing.T) {
 			_, errs = ctx.PrepareBuildActions(config)
 			fail(t, errs)
 
-			foo := findModule(ctx, "foo")
+			foo := ctx.ModuleForTests("foo", "")
-			if foo == nil {
-				t.Fatalf("failed to find module foo")
-			}
 
 			var dependsOnSourceModule, dependsOnPrebuiltModule bool
-			ctx.VisitDirectDeps(foo, func(m blueprint.Module) {
+			ctx.VisitDirectDeps(foo.Module(), func(m blueprint.Module) {
 				if _, ok := m.(*sourceModule); ok {
 					dependsOnSourceModule = true
 				}
@@ -228,16 +228,6 @@ func (s *sourceModule) DepsMutator(ctx BottomUpMutatorContext) {
 func (s *sourceModule) GenerateAndroidBuildActions(ctx ModuleContext) {
 }
 
-func findModule(ctx *blueprint.Context, name string) blueprint.Module {
-	var ret blueprint.Module
-	ctx.VisitAllModules(func(m blueprint.Module) {
-		if ctx.ModuleName(m) == name {
-			ret = m
-		}
-	})
-	return ret
-}
-
 func fail(t *testing.T, errs []error) {
 	if len(errs) > 0 {
 		for _, err := range errs {

android/register.go

@@ -60,9 +60,15 @@ func RegisterSingletonType(name string, factory blueprint.SingletonFactory) {
 	singletons = append(singletons, singleton{name, factory})
 }
 
-func NewContext() *blueprint.Context {
+type Context struct {
-	ctx := blueprint.NewContext()
+	*blueprint.Context
+}
 
+func NewContext() *Context {
+	return &Context{blueprint.NewContext()}
+}
+
+func (ctx *Context) Register() {
 	for _, t := range moduleTypes {
 		ctx.RegisterModuleType(t.name, t.factory)
 	}
@@ -71,9 +77,7 @@ func NewContext() *blueprint.Context {
 		ctx.RegisterSingletonType(t.name, t.factory)
 	}
 
-	registerMutators(ctx)
+	registerMutators(ctx.Context, preArch, preDeps, postDeps)
 
 	ctx.RegisterSingletonType("env", EnvSingleton)
-
-	return ctx
 }

android/testing.go

@@ -0,0 +1,98 @@
+// Copyright 2017 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 android
+
+import (
+	"fmt"
+	"strings"
+
+	"github.com/google/blueprint"
+)
+
+func NewTestContext() *TestContext {
+	return &TestContext{
+		Context: blueprint.NewContext(),
+	}
+}
+
+type TestContext struct {
+	*blueprint.Context
+	preArch, preDeps, postDeps []RegisterMutatorFunc
+}
+
+func (ctx *TestContext) PreArchMutators(f RegisterMutatorFunc) {
+	ctx.preArch = append(ctx.preArch, f)
+}
+
+func (ctx *TestContext) PreDepsMutators(f RegisterMutatorFunc) {
+	ctx.preDeps = append(ctx.preDeps, f)
+}
+
+func (ctx *TestContext) PostDepsMutators(f RegisterMutatorFunc) {
+	ctx.postDeps = append(ctx.postDeps, f)
+}
+
+func (ctx *TestContext) Register() {
+	registerMutators(ctx.Context, ctx.preArch, ctx.preDeps, ctx.postDeps)
+
+	ctx.RegisterSingletonType("env", EnvSingleton)
+}
+
+func (ctx *TestContext) ModuleForTests(name, variant string) TestingModule {
+	var module Module
+	ctx.VisitAllModules(func(m blueprint.Module) {
+		if ctx.ModuleName(m) == name && ctx.ModuleSubDir(m) == variant {
+			module = m.(Module)
+		}
+	})
+
+	if module == nil {
+		panic(fmt.Errorf("failed to find module %q variant %q", name, variant))
+	}
+
+	return TestingModule{module}
+}
+
+type TestingModule struct {
+	module Module
+}
+
+func (m TestingModule) Module() Module {
+	return m.module
+}
+
+func (m TestingModule) Rule(rule string) ModuleBuildParams {
+	for _, p := range m.module.BuildParamsForTests() {
+		if strings.Contains(p.Rule.String(), rule) {
+			return p
+		}
+	}
+	panic(fmt.Errorf("couldn't find rule %q", rule))
+}
+
+func (m TestingModule) Output(file string) ModuleBuildParams {
+	for _, p := range m.module.BuildParamsForTests() {
+		outputs := append(WritablePaths(nil), p.Outputs...)
+		if p.Output != nil {
+			outputs = append(outputs, p.Output)
+		}
+		for _, f := range outputs {
+			if f.Base() == file {
+				return p
+			}
+		}
+	}
+	panic(fmt.Errorf("couldn't find output %q", file))
+}

cc/test_data_test.go

@@ -23,8 +23,6 @@ import (
 
 	"android/soong/android"
 	"android/soong/genrule"
-
-	"github.com/google/blueprint"
 )
 
 type dataFile struct {
@@ -123,8 +121,7 @@ func TestDataTests(t *testing.T) {
 
 	for _, test := range testDataTests {
 		t.Run(test.name, func(t *testing.T) {
-			ctx := blueprint.NewContext()
+			ctx := android.NewTestContext()
-			android.RegisterTestMutators(ctx)
 			ctx.MockFileSystem(map[string][]byte{
 				"Blueprints":     []byte(`subdirs = ["dir"]`),
 				"dir/Blueprints": []byte(test.modules),
@@ -135,18 +132,16 @@ func TestDataTests(t *testing.T) {
 				android.ModuleFactoryAdaptor(genrule.FileGroupFactory))
 			ctx.RegisterModuleType("test",
 				android.ModuleFactoryAdaptor(newTest))
+			ctx.Register()
 
 			_, errs := ctx.ParseBlueprintsFiles("Blueprints")
 			fail(t, errs)
 			_, errs = ctx.PrepareBuildActions(config)
 			fail(t, errs)
 
-			foo := findModule(ctx, "foo")
+			foo := ctx.ModuleForTests("foo", "")
-			if foo == nil {
-				t.Fatalf("failed to find module foo")
-			}
 
-			got := foo.(*testDataTest).data
+			got := foo.Module().(*testDataTest).data
 			if len(got) != len(test.data) {
 				t.Errorf("expected %d data files, got %d",
 					len(test.data), len(got))
@@ -192,16 +187,6 @@ func (test *testDataTest) GenerateAndroidBuildActions(ctx android.ModuleContext)
 	test.data = ctx.ExpandSources(test.Properties.Data, nil)
 }
 
-func findModule(ctx *blueprint.Context, name string) blueprint.Module {
-	var ret blueprint.Module
-	ctx.VisitAllModules(func(m blueprint.Module) {
-		if ctx.ModuleName(m) == name {
-			ret = m
-		}
-	})
-	return ret
-}
-
 func fail(t *testing.T, errs []error) {
 	if len(errs) > 0 {
 		for _, err := range errs {

cmd/soong_build/main.go

@@ -32,6 +32,7 @@ func main() {
 	srcDir := filepath.Dir(flag.Arg(0))
 
 	ctx := android.NewContext()
+	ctx.Register()
 
 	configuration, err := android.NewConfig(srcDir, bootstrap.BuildDir)
 	if err != nil {
@@ -44,5 +45,5 @@ func main() {
 
 	ctx.SetAllowMissingDependencies(configuration.AllowMissingDependencies())
 
-	bootstrap.Main(ctx, configuration, configuration.ConfigFileName, configuration.ProductVariablesFileName)
+	bootstrap.Main(ctx.Context, configuration, configuration.ConfigFileName, configuration.ProductVariablesFileName)
 }

python/python_test.go

@@ -26,8 +26,6 @@ import (
 	"testing"
 
 	"android/soong/android"
-
-	"github.com/google/blueprint"
 )
 
 type pyBinary struct {
@@ -306,17 +304,17 @@ var (
 func TestPythonModule(t *testing.T) {
 	config, buildDir := setupBuildEnv(t)
 	defer tearDownBuildEnv(buildDir)
-	android.TestPreDepsMutators(func(ctx android.RegisterMutatorsContext) {
-		ctx.BottomUp("version_split", versionSplitMutator()).Parallel()
-	})
 	for _, d := range data {
 		t.Run(d.desc, func(t *testing.T) {
-			ctx := blueprint.NewContext()
+			ctx := android.NewTestContext()
-			android.RegisterTestMutators(ctx)
+			ctx.PreDepsMutators(func(ctx android.RegisterMutatorsContext) {
+				ctx.BottomUp("version_split", versionSplitMutator()).Parallel()
+			})
 			ctx.RegisterModuleType("python_library_host",
 				android.ModuleFactoryAdaptor(PythonLibraryHostFactory))
 			ctx.RegisterModuleType("python_binary_host",
 				android.ModuleFactoryAdaptor(PythonBinaryHostFactory))
+			ctx.Register()
 			ctx.MockFileSystem(d.mockFiles)
 			_, testErrs := ctx.ParseBlueprintsFiles(bpFile)
 			fail(t, testErrs)
@@ -360,15 +358,12 @@ func expectErrors(t *testing.T, actErrs []error, expErrs []string) (testErrs []e
 	return
 }
 
-func expectModule(t *testing.T, ctx *blueprint.Context, buildDir, name, variant string,
+func expectModule(t *testing.T, ctx *android.TestContext, buildDir, name, variant string,
 	expPyRunfiles, expDepsPyRunfiles []string,
 	expParSpec string, expDepsParSpecs []string) (testErrs []error) {
-	module := findModule(ctx, name, variant)
+	module := ctx.ModuleForTests(name, variant)
-	if module == nil {
-		t.Fatalf("failed to find module %s!", name)
-	}
 
-	base, baseOk := module.(*pythonBaseModule)
+	base, baseOk := module.Module().(*pythonBaseModule)
 	if !baseOk {
 		t.Fatalf("%s is not Python module!", name)
 	}
@@ -438,16 +433,6 @@ func tearDownBuildEnv(buildDir string) {
 	os.RemoveAll(buildDir)
 }
 
-func findModule(ctx *blueprint.Context, name, variant string) blueprint.Module {
-	var ret blueprint.Module
-	ctx.VisitAllModules(func(m blueprint.Module) {
-		if ctx.ModuleName(m) == name && ctx.ModuleSubDir(m) == variant {
-			ret = m
-		}
-	})
-	return ret
-}
-
 func fail(t *testing.T, errs []error) {
 	if len(errs) > 0 {
 		for _, err := range errs {