android/namespace_test.go - platform/build/soong - Git at Google

 // 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 (
 	"errors"
 	"io/ioutil"
 	"os"
 	"path/filepath"
 	"reflect"
 	"testing"

 	"github.com/google/blueprint"
 )

 func TestDependingOnModuleInSameNamespace(t *testing.T) {
 	ctx := setupTest(t,
 		map[string]string{
 			"dir1": `
 			soong_namespace {
 			}
 			test_module {
 				name: "a",
 			}
 			test_module {
 				name: "b",
 				deps: ["a"],
 			}
 			`,
 		},
 	)

 	a := getModule(ctx, "a")
 	b := getModule(ctx, "b")
 	if !dependsOn(ctx, b, a) {
 		t.Errorf("module b does not depend on module a in the same namespace")
 	}
 }

 func TestDependingOnModuleInRootNamespace(t *testing.T) {
 	ctx := setupTest(t,
 		map[string]string{
 			".": `
 			test_module {
 				name: "b",
 				deps: ["a"],
 			}
 			test_module {
 				name: "a",
 			}
 			`,
 		},
 	)

 	a := getModule(ctx, "a")
 	b := getModule(ctx, "b")
 	if !dependsOn(ctx, b, a) {
 		t.Errorf("module b in root namespace does not depend on module a in the root namespace")
 	}
 }

 func TestImplicitlyImportRootNamespace(t *testing.T) {
 	_ = setupTest(t,
 		map[string]string{
 			".": `
 			test_module {
 				name: "a",
 			}
 			`,
 			"dir1": `
 			soong_namespace {
 			}
 			test_module {
 				name: "b",
 				deps: ["a"],
 			}
 			`,
 		},
 	)

 	// setupTest will report any errors
 }

 func TestDependingOnModuleInImportedNamespace(t *testing.T) {
 	ctx := setupTest(t,
 		map[string]string{
 			"dir1": `
 			soong_namespace {
 			}
 			test_module {
 				name: "a",
 			}
 			`,
 			"dir2": `
 			soong_namespace {
 				imports: ["dir1"],
 			}
 			test_module {
 				name: "b",
 				deps: ["a"],
 			}
 			`,
 		},
 	)

 	a := getModule(ctx, "a")
 	b := getModule(ctx, "b")
 	if !dependsOn(ctx, b, a) {
 		t.Errorf("module b does not depend on module a in the same namespace")
 	}
 }

 func TestDependingOnModuleInNonImportedNamespace(t *testing.T) {
 	_, errs := setupTestExpectErrs(
 		map[string]string{
 			"dir1": `
 			soong_namespace {
 			}
 			test_module {
 				name: "a",
 			}
 			`,
 			"dir2": `
 			soong_namespace {
 			}
 			test_module {
 				name: "a",
 			}
 			`,
 			"dir3": `
 			soong_namespace {
 			}
 			test_module {
 				name: "b",
 				deps: ["a"],
 			}
 			`,
 		},
 	)

 	expectedErrors := []error{
 		errors.New(
 			`dir3/Android.bp:4:4: "b" depends on undefined module "a"
 Module "b" is defined in namespace "dir3" which can read these 2 namespaces: ["dir3" "."]
 Module "a" can be found in these namespaces: ["dir1" "dir2"]`),
 	}

 	if len(errs) != 1 || errs[0].Error() != expectedErrors[0].Error() {
 		t.Errorf("Incorrect errors. Expected:\n%v\n, got:\n%v\n", expectedErrors, errs)
 	}
 }

 func TestDependingOnModuleByFullyQualifiedReference(t *testing.T) {
 	ctx := setupTest(t,
 		map[string]string{
 			"dir1": `
 			soong_namespace {
 			}
 			test_module {
 				name: "a",
 			}
 			`,
 			"dir2": `
 			soong_namespace {
 			}
 			test_module {
 				name: "b",
 				deps: ["//dir1:a"],
 			}
 			`,
 		},
 	)
 	a := getModule(ctx, "a")
 	b := getModule(ctx, "b")
 	if !dependsOn(ctx, b, a) {
 		t.Errorf("module b does not depend on module a")
 	}
 }

 func TestSameNameInTwoNamespaces(t *testing.T) {
 	ctx := setupTest(t,
 		map[string]string{
 			"dir1": `
 			soong_namespace {
 			}
 			test_module {
 				name: "a",
 				id: "1",
 			}
 			test_module {
 				name: "b",
 				deps: ["a"],
 				id: "2",
 			}
 			`,
 			"dir2": `
 			soong_namespace {
 			}
 			test_module {
 				name: "a",
 				id:"3",
 			}
 			test_module {
 				name: "b",
 				deps: ["a"],
 				id:"4",
 			}
 			`,
 		},
 	)

 	one := findModuleById(ctx, "1")
 	two := findModuleById(ctx, "2")
 	three := findModuleById(ctx, "3")
 	four := findModuleById(ctx, "4")
 	if !dependsOn(ctx, two, one) {
 		t.Fatalf("Module 2 does not depend on module 1 in its namespace")
 	}
 	if dependsOn(ctx, two, three) {
 		t.Fatalf("Module 2 depends on module 3 in another namespace")
 	}
 	if !dependsOn(ctx, four, three) {
 		t.Fatalf("Module 4 does not depend on module 3 in its namespace")
 	}
 	if dependsOn(ctx, four, one) {
 		t.Fatalf("Module 4 depends on module 1 in another namespace")
 	}
 }

 func TestSearchOrder(t *testing.T) {
 	ctx := setupTest(t,
 		map[string]string{
 			"dir1": `
 			soong_namespace {
 			}
 			test_module {
 				name: "a",
 				id: "1",
 			}
 			`,
 			"dir2": `
 			soong_namespace {
 			}
 			test_module {
 				name: "a",
 				id:"2",
 			}
 			test_module {
 				name: "b",
 				id:"3",
 			}
 			`,
 			"dir3": `
 			soong_namespace {
 			}
 			test_module {
 				name: "a",
 				id:"4",
 			}
 			test_module {
 				name: "b",
 				id:"5",
 			}
 			test_module {
 				name: "c",
 				id:"6",
 			}
 			`,
 			".": `
 			test_module {
 				name: "a",
 				id: "7",
 			}
 			test_module {
 				name: "b",
 				id: "8",
 			}
 			test_module {
 				name: "c",
 				id: "9",
 			}
 			test_module {
 				name: "d",
 				id: "10",
 			}
 			`,
 			"dir4": `
 			soong_namespace {
 				imports: ["dir1", "dir2", "dir3"]
 			}
 			test_module {
 				name: "test_me",
 				id:"0",
 				deps: ["a", "b", "c", "d"],
 			}
 			`,
 		},
 	)

 	testMe := findModuleById(ctx, "0")
 	if !dependsOn(ctx, testMe, findModuleById(ctx, "1")) {
 		t.Errorf("test_me doesn't depend on id 1")
 	}
 	if !dependsOn(ctx, testMe, findModuleById(ctx, "3")) {
 		t.Errorf("test_me doesn't depend on id 3")
 	}
 	if !dependsOn(ctx, testMe, findModuleById(ctx, "6")) {
 		t.Errorf("test_me doesn't depend on id 6")
 	}
 	if !dependsOn(ctx, testMe, findModuleById(ctx, "10")) {
 		t.Errorf("test_me doesn't depend on id 10")
 	}
 	if numDeps(ctx, testMe) != 4 {
 		t.Errorf("num dependencies of test_me = %v, not 4\n", numDeps(ctx, testMe))
 	}
 }

 func TestTwoNamespacesCanImportEachOther(t *testing.T) {
 	_ = setupTest(t,
 		map[string]string{
 			"dir1": `
 			soong_namespace {
 				imports: ["dir2"]
 			}
 			test_module {
 				name: "a",
 			}
 			test_module {
 				name: "c",
 				deps: ["b"],
 			}
 			`,
 			"dir2": `
 			soong_namespace {
 				imports: ["dir1"],
 			}
 			test_module {
 				name: "b",
 				deps: ["a"],
 			}
 			`,
 		},
 	)

 	// setupTest will report any errors
 }

 func TestImportingNonexistentNamespace(t *testing.T) {
 	_, errs := setupTestExpectErrs(
 		map[string]string{
 			"dir1": `
 			soong_namespace {
 				imports: ["a_nonexistent_namespace"]
 			}
 			test_module {
 				name: "a",
 				deps: ["a_nonexistent_module"]
 			}
 			`,
 		},
 	)

 	// should complain about the missing namespace and not complain about the unresolvable dependency
 	expectedErrors := []error{
 		errors.New(`dir1/Android.bp:2:4: module "soong_namespace": namespace a_nonexistent_namespace does not exist`),
 	}
 	if len(errs) != 1 || errs[0].Error() != expectedErrors[0].Error() {
 		t.Errorf("Incorrect errors. Expected:\n%v\n, got:\n%v\n", expectedErrors, errs)
 	}
 }

 func TestNamespacesDontInheritParentNamespaces(t *testing.T) {
 	_, errs := setupTestExpectErrs(
 		map[string]string{
 			"dir1": `
 			soong_namespace {
 			}
 			test_module {
 				name: "a",
 			}
 			`,
 			"dir1/subdir1": `
 			soong_namespace {
 			}
 			test_module {
 				name: "b",
 				deps: ["a"],
 			}
 			`,
 		},
 	)

 	expectedErrors := []error{
 		errors.New(`dir1/subdir1/Android.bp:4:4: "b" depends on undefined module "a"
 Module "b" is defined in namespace "dir1/subdir1" which can read these 2 namespaces: ["dir1/subdir1" "."]
 Module "a" can be found in these namespaces: ["dir1"]`),
 	}
 	if len(errs) != 1 || errs[0].Error() != expectedErrors[0].Error() {
 		t.Errorf("Incorrect errors. Expected:\n%v\n, got:\n%v\n", expectedErrors, errs)
 	}
 }

 func TestModulesDoReceiveParentNamespace(t *testing.T) {
 	_ = setupTest(t,
 		map[string]string{
 			"dir1": `
 			soong_namespace {
 			}
 			test_module {
 				name: "a",
 			}
 			`,
 			"dir1/subdir": `
 			test_module {
 				name: "b",
 				deps: ["a"],
 			}
 			`,
 		},
 	)

 	// setupTest will report any errors
 }

 func TestNamespaceImportsNotTransitive(t *testing.T) {
 	_, errs := setupTestExpectErrs(
 		map[string]string{
 			"dir1": `
 			soong_namespace {
 			}
 			test_module {
 				name: "a",
 			}
 			`,
 			"dir2": `
 			soong_namespace {
 				imports: ["dir1"],
 			}
 			test_module {
 				name: "b",
 				deps: ["a"],
 			}
 			`,
 			"dir3": `
 			soong_namespace {
 				imports: ["dir2"],
 			}
 			test_module {
 				name: "c",
 				deps: ["a"],
 			}
 			`,
 		},
 	)

 	expectedErrors := []error{
 		errors.New(`dir3/Android.bp:5:4: "c" depends on undefined module "a"
 Module "c" is defined in namespace "dir3" which can read these 3 namespaces: ["dir3" "dir2" "."]
 Module "a" can be found in these namespaces: ["dir1"]`),
 	}
 	if len(errs) != 1 || errs[0].Error() != expectedErrors[0].Error() {
 		t.Errorf("Incorrect errors. Expected:\n%v\n, got:\n%v\n", expectedErrors, errs)
 	}
 }

 func TestTwoNamepacesInSameDir(t *testing.T) {
 	_, errs := setupTestExpectErrs(
 		map[string]string{
 			"dir1": `
 			soong_namespace {
 			}
 			soong_namespace {
 			}
 			`,
 		},
 	)

 	expectedErrors := []error{
 		errors.New(`dir1/Android.bp:4:4: namespace dir1 already exists`),
 	}
 	if len(errs) != 1 || errs[0].Error() != expectedErrors[0].Error() {
 		t.Errorf("Incorrect errors. Expected:\n%v\n, got:\n%v\n", expectedErrors, errs)
 	}
 }

 func TestNamespaceNotAtTopOfFile(t *testing.T) {
 	_, errs := setupTestExpectErrs(
 		map[string]string{
 			"dir1": `
 			test_module {
 				name: "a"
 			}
 			soong_namespace {
 			}
 			`,
 		},
 	)

 	expectedErrors := []error{
 		errors.New(`dir1/Android.bp:5:4: a namespace must be the first module in the file`),
 	}
 	if len(errs) != 1 || errs[0].Error() != expectedErrors[0].Error() {
 		t.Errorf("Incorrect errors. Expected:\n%v\n, got:\n%v\n", expectedErrors, errs)
 	}
 }

 func TestTwoModulesWithSameNameInSameNamespace(t *testing.T) {
 	_, errs := setupTestExpectErrs(
 		map[string]string{
 			"dir1": `
 			soong_namespace {
 			}
 			test_module {
 				name: "a"
 			}
 			test_module {
 				name: "a"
 			}
 			`,
 		},
 	)

 	expectedErrors := []error{
 		errors.New(`dir1/Android.bp:7:4: module "a" already defined
        dir1/Android.bp:4:4 <-- previous definition here`),
 	}
 	if len(errs) != 1 || errs[0].Error() != expectedErrors[0].Error() {
 		t.Errorf("Incorrect errors. Expected:\n%v\n, got:\n%v\n", expectedErrors, errs)
 	}
 }

 func TestDeclaringNamespaceInNonAndroidBpFile(t *testing.T) {
 	_, errs := setupTestFromFiles(
 		map[string][]byte{
 			"Android.bp": []byte(`
 				build = ["include.bp"]
 			`),
 			"include.bp": []byte(`
 				soong_namespace {
 				}
 			`),
 		},
 	)

 	expectedErrors := []error{
 		errors.New(`include.bp:2:5: A namespace may only be declared in a file named Android.bp`),
 	}

 	if len(errs) != 1 || errs[0].Error() != expectedErrors[0].Error() {
 		t.Errorf("Incorrect errors. Expected:\n%v\n, got:\n%v\n", expectedErrors, errs)
 	}
 }

 // so that the generated .ninja file will have consistent names
 func TestConsistentNamespaceNames(t *testing.T) {
 	ctx := setupTest(t,
 		map[string]string{
 			"dir1": "soong_namespace{}",
 			"dir2": "soong_namespace{}",
 			"dir3": "soong_namespace{}",
 		})

 	ns1, _ := ctx.NameResolver.namespaceAt("dir1")
 	ns2, _ := ctx.NameResolver.namespaceAt("dir2")
 	ns3, _ := ctx.NameResolver.namespaceAt("dir3")
 	actualIds := []string{ns1.id, ns2.id, ns3.id}
 	expectedIds := []string{"1", "2", "3"}
 	if !reflect.DeepEqual(actualIds, expectedIds) {
 		t.Errorf("Incorrect namespace ids.\nactual: %s\nexpected: %s\n", actualIds, expectedIds)
 	}
 }

 // so that the generated .ninja file will have consistent names
 func TestRename(t *testing.T) {
 	_ = setupTest(t,
 		map[string]string{
 			"dir1": `
 			soong_namespace {
 			}
 			test_module {
 				name: "a",
 				deps: ["c"],
 			}
 			test_module {
 				name: "b",
 				rename: "c",
 			}
 		`})
 	// setupTest will report any errors
 }

 // some utils to support the tests

 func mockFiles(bps map[string]string) (files map[string][]byte) {
 	files = make(map[string][]byte, len(bps))
 	files["Android.bp"] = []byte("")
 	for dir, text := range bps {
 		files[filepath.Join(dir, "Android.bp")] = []byte(text)
 	}
 	return files
 }

 func setupTestFromFiles(bps map[string][]byte) (ctx *TestContext, errs []error) {
 	buildDir, err := ioutil.TempDir("", "soong_namespace_test")
 	if err != nil {
 		return nil, []error{err}
 	}
 	defer os.RemoveAll(buildDir)

 	config := TestConfig(buildDir, nil)

 	ctx = NewTestContext()
 	ctx.MockFileSystem(bps)
 	ctx.RegisterModuleType("test_module", ModuleFactoryAdaptor(newTestModule))
 	ctx.RegisterModuleType("soong_namespace", ModuleFactoryAdaptor(NamespaceFactory))
 	ctx.PreArchMutators(RegisterNamespaceMutator)
 	ctx.PreDepsMutators(func(ctx RegisterMutatorsContext) {
 		ctx.BottomUp("rename", renameMutator)
 	})
 	ctx.Register()

 	_, errs = ctx.ParseBlueprintsFiles("Android.bp")
 	if len(errs) > 0 {
 		return ctx, errs
 	}
 	_, errs = ctx.PrepareBuildActions(config)
 	return ctx, errs
 }

 func setupTestExpectErrs(bps map[string]string) (ctx *TestContext, errs []error) {
 	files := make(map[string][]byte, len(bps))
 	files["Android.bp"] = []byte("")
 	for dir, text := range bps {
 		files[filepath.Join(dir, "Android.bp")] = []byte(text)
 	}
 	return setupTestFromFiles(files)
 }

 func setupTest(t *testing.T, bps map[string]string) (ctx *TestContext) {
 	ctx, errs := setupTestExpectErrs(bps)
 	FailIfErrored(t, errs)
 	return ctx
 }

 func dependsOn(ctx *TestContext, module TestingModule, possibleDependency TestingModule) bool {
 	depends := false
 	visit := func(dependency blueprint.Module) {
 		if dependency == possibleDependency.module {
 			depends = true
 		}
 	}
 	ctx.VisitDirectDeps(module.module, visit)
 	return depends
 }

 func numDeps(ctx *TestContext, module TestingModule) int {
 	count := 0
 	visit := func(dependency blueprint.Module) {
 		count++
 	}
 	ctx.VisitDirectDeps(module.module, visit)
 	return count
 }

 func getModule(ctx *TestContext, moduleName string) TestingModule {
 	return ctx.ModuleForTests(moduleName, "")
 }

 func findModuleById(ctx *TestContext, id string) (module TestingModule) {
 	visit := func(candidate blueprint.Module) {
 		testModule, ok := candidate.(*testModule)
 		if ok {
 			if testModule.properties.Id == id {
 				module = TestingModule{testModule}
 			}
 		}
 	}
 	ctx.VisitAllModules(visit)
 	return module
 }

 type testModule struct {
 	ModuleBase
 	properties struct {
 		Rename string
 		Deps   []string
 		Id     string
 	}
 }

 func (m *testModule) DepsMutator(ctx BottomUpMutatorContext) {
 	if m.properties.Rename != "" {
 		ctx.Rename(m.properties.Rename)
 	}
 	for _, d := range m.properties.Deps {
 		ctx.AddDependency(ctx.Module(), nil, d)
 	}
 }

 func (m *testModule) GenerateAndroidBuildActions(ModuleContext) {
 }

 func renameMutator(ctx BottomUpMutatorContext) {
 	if m, ok := ctx.Module().(*testModule); ok {
 		if m.properties.Rename != "" {
 			ctx.Rename(m.properties.Rename)
 		}
 	}
 }

 func newTestModule() Module {
 	m := &testModule{}
 	m.AddProperties(&m.properties)
 	InitAndroidModule(m)
 	return m
 }
	// 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 (
	"errors"
	"io/ioutil"
	"os"
	"path/filepath"
	"reflect"
	"testing"

	"github.com/google/blueprint"
	)

	func TestDependingOnModuleInSameNamespace(t *testing.T) {
	ctx := setupTest(t,
	map[string]string{
	"dir1": `
	soong_namespace {
	}
	test_module {
	name: "a",
	}
	test_module {
	name: "b",
	deps: ["a"],
	}
	`,
	},
	)

	a := getModule(ctx, "a")
	b := getModule(ctx, "b")
	if !dependsOn(ctx, b, a) {
	t.Errorf("module b does not depend on module a in the same namespace")
	}
	}

	func TestDependingOnModuleInRootNamespace(t *testing.T) {
	ctx := setupTest(t,
	map[string]string{
	".": `
	test_module {
	name: "b",
	deps: ["a"],
	}
	test_module {
	name: "a",
	}
	`,
	},
	)

	a := getModule(ctx, "a")
	b := getModule(ctx, "b")
	if !dependsOn(ctx, b, a) {
	t.Errorf("module b in root namespace does not depend on module a in the root namespace")
	}
	}

	func TestImplicitlyImportRootNamespace(t *testing.T) {
	_ = setupTest(t,
	map[string]string{
	".": `
	test_module {
	name: "a",
	}
	`,
	"dir1": `
	soong_namespace {
	}
	test_module {
	name: "b",
	deps: ["a"],
	}
	`,
	},
	)

	// setupTest will report any errors
	}

	func TestDependingOnModuleInImportedNamespace(t *testing.T) {
	ctx := setupTest(t,
	map[string]string{
	"dir1": `
	soong_namespace {
	}
	test_module {
	name: "a",
	}
	`,
	"dir2": `
	soong_namespace {
	imports: ["dir1"],
	}
	test_module {
	name: "b",
	deps: ["a"],
	}
	`,
	},
	)

	a := getModule(ctx, "a")
	b := getModule(ctx, "b")
	if !dependsOn(ctx, b, a) {
	t.Errorf("module b does not depend on module a in the same namespace")
	}
	}

	func TestDependingOnModuleInNonImportedNamespace(t *testing.T) {
	_, errs := setupTestExpectErrs(
	map[string]string{
	"dir1": `
	soong_namespace {
	}
	test_module {
	name: "a",
	}
	`,
	"dir2": `
	soong_namespace {
	}
	test_module {
	name: "a",
	}
	`,
	"dir3": `
	soong_namespace {
	}
	test_module {
	name: "b",
	deps: ["a"],
	}
	`,
	},
	)

	expectedErrors := []error{
	errors.New(
	`dir3/Android.bp:4:4: "b" depends on undefined module "a"
	Module "b" is defined in namespace "dir3" which can read these 2 namespaces: ["dir3" "."]
	Module "a" can be found in these namespaces: ["dir1" "dir2"]`),
	}

	if len(errs) != 1 \|\| errs[0].Error() != expectedErrors[0].Error() {
	t.Errorf("Incorrect errors. Expected:\n%v\n, got:\n%v\n", expectedErrors, errs)
	}
	}

	func TestDependingOnModuleByFullyQualifiedReference(t *testing.T) {
	ctx := setupTest(t,
	map[string]string{
	"dir1": `
	soong_namespace {
	}
	test_module {
	name: "a",
	}
	`,
	"dir2": `
	soong_namespace {
	}
	test_module {
	name: "b",
	deps: ["//dir1:a"],
	}
	`,
	},
	)
	a := getModule(ctx, "a")
	b := getModule(ctx, "b")
	if !dependsOn(ctx, b, a) {
	t.Errorf("module b does not depend on module a")
	}
	}

	func TestSameNameInTwoNamespaces(t *testing.T) {
	ctx := setupTest(t,
	map[string]string{
	"dir1": `
	soong_namespace {
	}
	test_module {
	name: "a",
	id: "1",
	}
	test_module {
	name: "b",
	deps: ["a"],
	id: "2",
	}
	`,
	"dir2": `
	soong_namespace {
	}
	test_module {
	name: "a",
	id:"3",
	}
	test_module {
	name: "b",
	deps: ["a"],
	id:"4",
	}
	`,
	},
	)

	one := findModuleById(ctx, "1")
	two := findModuleById(ctx, "2")
	three := findModuleById(ctx, "3")
	four := findModuleById(ctx, "4")
	if !dependsOn(ctx, two, one) {
	t.Fatalf("Module 2 does not depend on module 1 in its namespace")
	}
	if dependsOn(ctx, two, three) {
	t.Fatalf("Module 2 depends on module 3 in another namespace")
	}
	if !dependsOn(ctx, four, three) {
	t.Fatalf("Module 4 does not depend on module 3 in its namespace")
	}
	if dependsOn(ctx, four, one) {
	t.Fatalf("Module 4 depends on module 1 in another namespace")
	}
	}

	func TestSearchOrder(t *testing.T) {
	ctx := setupTest(t,
	map[string]string{
	"dir1": `
	soong_namespace {
	}
	test_module {
	name: "a",
	id: "1",
	}
	`,
	"dir2": `
	soong_namespace {
	}
	test_module {
	name: "a",
	id:"2",
	}
	test_module {
	name: "b",
	id:"3",
	}
	`,
	"dir3": `
	soong_namespace {
	}
	test_module {
	name: "a",
	id:"4",
	}
	test_module {
	name: "b",
	id:"5",
	}
	test_module {
	name: "c",
	id:"6",
	}
	`,
	".": `
	test_module {
	name: "a",
	id: "7",
	}
	test_module {
	name: "b",
	id: "8",
	}
	test_module {
	name: "c",
	id: "9",
	}
	test_module {
	name: "d",
	id: "10",
	}
	`,
	"dir4": `
	soong_namespace {
	imports: ["dir1", "dir2", "dir3"]
	}
	test_module {
	name: "test_me",
	id:"0",
	deps: ["a", "b", "c", "d"],
	}
	`,
	},
	)

	testMe := findModuleById(ctx, "0")
	if !dependsOn(ctx, testMe, findModuleById(ctx, "1")) {
	t.Errorf("test_me doesn't depend on id 1")
	}
	if !dependsOn(ctx, testMe, findModuleById(ctx, "3")) {
	t.Errorf("test_me doesn't depend on id 3")
	}
	if !dependsOn(ctx, testMe, findModuleById(ctx, "6")) {
	t.Errorf("test_me doesn't depend on id 6")
	}
	if !dependsOn(ctx, testMe, findModuleById(ctx, "10")) {
	t.Errorf("test_me doesn't depend on id 10")
	}
	if numDeps(ctx, testMe) != 4 {
	t.Errorf("num dependencies of test_me = %v, not 4\n", numDeps(ctx, testMe))
	}
	}

	func TestTwoNamespacesCanImportEachOther(t *testing.T) {
	_ = setupTest(t,
	map[string]string{
	"dir1": `
	soong_namespace {
	imports: ["dir2"]
	}
	test_module {
	name: "a",
	}
	test_module {
	name: "c",
	deps: ["b"],
	}
	`,
	"dir2": `
	soong_namespace {
	imports: ["dir1"],
	}
	test_module {
	name: "b",
	deps: ["a"],
	}
	`,
	},
	)

	// setupTest will report any errors
	}

	func TestImportingNonexistentNamespace(t *testing.T) {
	_, errs := setupTestExpectErrs(
	map[string]string{
	"dir1": `
	soong_namespace {
	imports: ["a_nonexistent_namespace"]
	}
	test_module {
	name: "a",
	deps: ["a_nonexistent_module"]
	}
	`,
	},
	)

	// should complain about the missing namespace and not complain about the unresolvable dependency
	expectedErrors := []error{
	errors.New(`dir1/Android.bp:2:4: module "soong_namespace": namespace a_nonexistent_namespace does not exist`),
	}
	if len(errs) != 1 \|\| errs[0].Error() != expectedErrors[0].Error() {
	t.Errorf("Incorrect errors. Expected:\n%v\n, got:\n%v\n", expectedErrors, errs)
	}
	}

	func TestNamespacesDontInheritParentNamespaces(t *testing.T) {
	_, errs := setupTestExpectErrs(
	map[string]string{
	"dir1": `
	soong_namespace {
	}
	test_module {
	name: "a",
	}
	`,
	"dir1/subdir1": `
	soong_namespace {
	}
	test_module {
	name: "b",
	deps: ["a"],
	}
	`,
	},
	)

	expectedErrors := []error{
	errors.New(`dir1/subdir1/Android.bp:4:4: "b" depends on undefined module "a"
	Module "b" is defined in namespace "dir1/subdir1" which can read these 2 namespaces: ["dir1/subdir1" "."]
	Module "a" can be found in these namespaces: ["dir1"]`),
	}
	if len(errs) != 1 \|\| errs[0].Error() != expectedErrors[0].Error() {
	t.Errorf("Incorrect errors. Expected:\n%v\n, got:\n%v\n", expectedErrors, errs)
	}
	}

	func TestModulesDoReceiveParentNamespace(t *testing.T) {
	_ = setupTest(t,
	map[string]string{
	"dir1": `
	soong_namespace {
	}
	test_module {
	name: "a",
	}
	`,
	"dir1/subdir": `
	test_module {
	name: "b",
	deps: ["a"],
	}
	`,
	},
	)

	// setupTest will report any errors
	}

	func TestNamespaceImportsNotTransitive(t *testing.T) {
	_, errs := setupTestExpectErrs(
	map[string]string{
	"dir1": `
	soong_namespace {
	}
	test_module {
	name: "a",
	}
	`,
	"dir2": `
	soong_namespace {
	imports: ["dir1"],
	}
	test_module {
	name: "b",
	deps: ["a"],
	}
	`,
	"dir3": `
	soong_namespace {
	imports: ["dir2"],
	}
	test_module {
	name: "c",
	deps: ["a"],
	}
	`,
	},
	)

	expectedErrors := []error{
	errors.New(`dir3/Android.bp:5:4: "c" depends on undefined module "a"
	Module "c" is defined in namespace "dir3" which can read these 3 namespaces: ["dir3" "dir2" "."]
	Module "a" can be found in these namespaces: ["dir1"]`),
	}
	if len(errs) != 1 \|\| errs[0].Error() != expectedErrors[0].Error() {
	t.Errorf("Incorrect errors. Expected:\n%v\n, got:\n%v\n", expectedErrors, errs)
	}
	}

	func TestTwoNamepacesInSameDir(t *testing.T) {
	_, errs := setupTestExpectErrs(
	map[string]string{
	"dir1": `
	soong_namespace {
	}
	soong_namespace {
	}
	`,
	},
	)

	expectedErrors := []error{
	errors.New(`dir1/Android.bp:4:4: namespace dir1 already exists`),
	}
	if len(errs) != 1 \|\| errs[0].Error() != expectedErrors[0].Error() {
	t.Errorf("Incorrect errors. Expected:\n%v\n, got:\n%v\n", expectedErrors, errs)
	}
	}

	func TestNamespaceNotAtTopOfFile(t *testing.T) {
	_, errs := setupTestExpectErrs(
	map[string]string{
	"dir1": `
	test_module {
	name: "a"
	}
	soong_namespace {
	}
	`,
	},
	)

	expectedErrors := []error{
	errors.New(`dir1/Android.bp:5:4: a namespace must be the first module in the file`),
	}
	if len(errs) != 1 \|\| errs[0].Error() != expectedErrors[0].Error() {
	t.Errorf("Incorrect errors. Expected:\n%v\n, got:\n%v\n", expectedErrors, errs)
	}
	}

	func TestTwoModulesWithSameNameInSameNamespace(t *testing.T) {
	_, errs := setupTestExpectErrs(
	map[string]string{
	"dir1": `
	soong_namespace {
	}
	test_module {
	name: "a"
	}
	test_module {
	name: "a"
	}
	`,
	},
	)

	expectedErrors := []error{
	errors.New(`dir1/Android.bp:7:4: module "a" already defined
	dir1/Android.bp:4:4 <-- previous definition here`),
	}
	if len(errs) != 1 \|\| errs[0].Error() != expectedErrors[0].Error() {
	t.Errorf("Incorrect errors. Expected:\n%v\n, got:\n%v\n", expectedErrors, errs)
	}
	}

	func TestDeclaringNamespaceInNonAndroidBpFile(t *testing.T) {
	_, errs := setupTestFromFiles(
	map[string][]byte{
	"Android.bp": []byte(`
	build = ["include.bp"]
	`),
	"include.bp": []byte(`
	soong_namespace {
	}
	`),
	},
	)

	expectedErrors := []error{
	errors.New(`include.bp:2:5: A namespace may only be declared in a file named Android.bp`),
	}

	if len(errs) != 1 \|\| errs[0].Error() != expectedErrors[0].Error() {
	t.Errorf("Incorrect errors. Expected:\n%v\n, got:\n%v\n", expectedErrors, errs)
	}
	}

	// so that the generated .ninja file will have consistent names
	func TestConsistentNamespaceNames(t *testing.T) {
	ctx := setupTest(t,
	map[string]string{
	"dir1": "soong_namespace{}",
	"dir2": "soong_namespace{}",
	"dir3": "soong_namespace{}",
	})

	ns1, _ := ctx.NameResolver.namespaceAt("dir1")
	ns2, _ := ctx.NameResolver.namespaceAt("dir2")
	ns3, _ := ctx.NameResolver.namespaceAt("dir3")
	actualIds := []string{ns1.id, ns2.id, ns3.id}
	expectedIds := []string{"1", "2", "3"}
	if !reflect.DeepEqual(actualIds, expectedIds) {
	t.Errorf("Incorrect namespace ids.\nactual: %s\nexpected: %s\n", actualIds, expectedIds)
	}
	}

	// so that the generated .ninja file will have consistent names
	func TestRename(t *testing.T) {
	_ = setupTest(t,
	map[string]string{
	"dir1": `
	soong_namespace {
	}
	test_module {
	name: "a",
	deps: ["c"],
	}
	test_module {
	name: "b",
	rename: "c",
	}
	`})
	// setupTest will report any errors
	}

	// some utils to support the tests

	func mockFiles(bps map[string]string) (files map[string][]byte) {
	files = make(map[string][]byte, len(bps))
	files["Android.bp"] = []byte("")
	for dir, text := range bps {
	files[filepath.Join(dir, "Android.bp")] = []byte(text)
	}
	return files
	}

	func setupTestFromFiles(bps map[string][]byte) (ctx *TestContext, errs []error) {
	buildDir, err := ioutil.TempDir("", "soong_namespace_test")
	if err != nil {
	return nil, []error{err}
	}
	defer os.RemoveAll(buildDir)

	config := TestConfig(buildDir, nil)

	ctx = NewTestContext()
	ctx.MockFileSystem(bps)
	ctx.RegisterModuleType("test_module", ModuleFactoryAdaptor(newTestModule))
	ctx.RegisterModuleType("soong_namespace", ModuleFactoryAdaptor(NamespaceFactory))
	ctx.PreArchMutators(RegisterNamespaceMutator)
	ctx.PreDepsMutators(func(ctx RegisterMutatorsContext) {
	ctx.BottomUp("rename", renameMutator)
	})
	ctx.Register()

	_, errs = ctx.ParseBlueprintsFiles("Android.bp")
	if len(errs) > 0 {
	return ctx, errs
	}
	_, errs = ctx.PrepareBuildActions(config)
	return ctx, errs
	}

	func setupTestExpectErrs(bps map[string]string) (ctx *TestContext, errs []error) {
	files := make(map[string][]byte, len(bps))
	files["Android.bp"] = []byte("")
	for dir, text := range bps {
	files[filepath.Join(dir, "Android.bp")] = []byte(text)
	}
	return setupTestFromFiles(files)
	}

	func setupTest(t testing.T, bps map[string]string) (ctx TestContext) {
	ctx, errs := setupTestExpectErrs(bps)
	FailIfErrored(t, errs)
	return ctx
	}

	func dependsOn(ctx *TestContext, module TestingModule, possibleDependency TestingModule) bool {
	depends := false
	visit := func(dependency blueprint.Module) {
	if dependency == possibleDependency.module {
	depends = true
	}
	}
	ctx.VisitDirectDeps(module.module, visit)
	return depends
	}

	func numDeps(ctx *TestContext, module TestingModule) int {
	count := 0
	visit := func(dependency blueprint.Module) {
	count++
	}
	ctx.VisitDirectDeps(module.module, visit)
	return count
	}

	func getModule(ctx *TestContext, moduleName string) TestingModule {
	return ctx.ModuleForTests(moduleName, "")
	}

	func findModuleById(ctx *TestContext, id string) (module TestingModule) {
	visit := func(candidate blueprint.Module) {
	testModule, ok := candidate.(*testModule)
	if ok {
	if testModule.properties.Id == id {
	module = TestingModule{testModule}
	}
	}
	}
	ctx.VisitAllModules(visit)
	return module
	}

	type testModule struct {
	ModuleBase
	properties struct {
	Rename string
	Deps []string
	Id string
	}
	}

	func (m *testModule) DepsMutator(ctx BottomUpMutatorContext) {
	if m.properties.Rename != "" {
	ctx.Rename(m.properties.Rename)
	}
	for _, d := range m.properties.Deps {
	ctx.AddDependency(ctx.Module(), nil, d)
	}
	}

	func (m *testModule) GenerateAndroidBuildActions(ModuleContext) {
	}

	func renameMutator(ctx BottomUpMutatorContext) {
	if m, ok := ctx.Module().(*testModule); ok {
	if m.properties.Rename != "" {
	ctx.Rename(m.properties.Rename)
	}
	}
	}

	func newTestModule() Module {
	m := &testModule{}
	m.AddProperties(&m.properties)
	InitAndroidModule(m)
	return m
	}