Add unit tests for android/neverallow.go

Bug: 74506774
Test: lunch aosp_walleye-userdebug && make  # runs unit tests
Change-Id: Ibde685d7213713be219681cb039ad58a43d9c377
diff --git a/Android.bp b/Android.bp
index 1d2c516..00db8f2d 100644
--- a/Android.bp
+++ b/Android.bp
@@ -71,6 +71,7 @@
         "android/config_test.go",
         "android/expand_test.go",
         "android/namespace_test.go",
+        "android/neverallow_test.go",
         "android/paths_test.go",
         "android/prebuilt_test.go",
         "android/util_test.go",
diff --git a/android/neverallow_test.go b/android/neverallow_test.go
new file mode 100644
index 0000000..19eeb22
--- /dev/null
+++ b/android/neverallow_test.go
@@ -0,0 +1,195 @@
+// Copyright 2018 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 (
+	"io/ioutil"
+	"os"
+	"testing"
+)
+
+var neverallowTests = []struct {
+	name          string
+	fs            map[string][]byte
+	expectedError string
+}{
+	{
+		name: "no vndk.enabled under vendor directory",
+		fs: map[string][]byte{
+			"vendor/Blueprints": []byte(`
+				cc_library {
+					name: "libvndk",
+					vendor_available: true,
+					vndk: {
+						enabled: true,
+					},
+				}`),
+		},
+		expectedError: "VNDK can never contain a library that is device dependent",
+	},
+	{
+		name: "no vndk.enabled under device directory",
+		fs: map[string][]byte{
+			"device/Blueprints": []byte(`
+				cc_library {
+					name: "libvndk",
+					vendor_available: true,
+					vndk: {
+						enabled: true,
+					},
+				}`),
+		},
+		expectedError: "VNDK can never contain a library that is device dependent",
+	},
+
+	{
+		name: "no enforce_vintf_manifest.cflags",
+		fs: map[string][]byte{
+			"Blueprints": []byte(`
+				cc_library {
+					name: "libexample",
+					product_variables: {
+						enforce_vintf_manifest: {
+							cflags: ["-DSHOULD_NOT_EXIST"],
+						},
+					},
+				}`),
+		},
+		expectedError: "manifest enforcement should be independent",
+	},
+	{
+		name: "libhidltransport enforce_vintf_manifest.cflags",
+		fs: map[string][]byte{
+			"Blueprints": []byte(`
+				cc_library {
+					name: "libhidltransport",
+					product_variables: {
+						enforce_vintf_manifest: {
+							cflags: ["-DSHOULD_NOT_EXIST"],
+						},
+					},
+				}`),
+		},
+		expectedError: "",
+	},
+
+	{
+		name: "no treble_linker_namespaces.cflags",
+		fs: map[string][]byte{
+			"Blueprints": []byte(`
+				cc_library {
+					name: "libexample",
+					product_variables: {
+						treble_linker_namespaces: {
+							cflags: ["-DSHOULD_NOT_EXIST"],
+						},
+					},
+				}`),
+		},
+		expectedError: "nothing should care if linker namespaces are enabled or not",
+	},
+	{
+		name: "libc_bionic_ndk treble_linker_namespaces.cflags",
+		fs: map[string][]byte{
+			"Blueprints": []byte(`
+				cc_library {
+					name: "libc_bionic_ndk",
+					product_variables: {
+						treble_linker_namespaces: {
+							cflags: ["-DSHOULD_NOT_EXIST"],
+						},
+					},
+				}`),
+		},
+		expectedError: "",
+	},
+}
+
+func TestNeverallow(t *testing.T) {
+	buildDir, err := ioutil.TempDir("", "soong_neverallow_test")
+	if err != nil {
+		t.Fatal(err)
+	}
+	defer os.RemoveAll(buildDir)
+
+	config := TestConfig(buildDir, nil)
+
+	for _, test := range neverallowTests {
+		t.Run(test.name, func(t *testing.T) {
+			_, errs := testNeverallow(t, config, test.fs)
+
+			if test.expectedError == "" {
+				FailIfErrored(t, errs)
+			} else {
+				FailIfNoMatchingErrors(t, test.expectedError, errs)
+			}
+		})
+	}
+}
+
+func testNeverallow(t *testing.T, config Config, fs map[string][]byte) (*TestContext, []error) {
+	ctx := NewTestContext()
+	ctx.RegisterModuleType("cc_library", ModuleFactoryAdaptor(newMockCcLibraryModule))
+	ctx.PostDepsMutators(registerNeverallowMutator)
+	ctx.Register()
+
+	ctx.MockFileSystem(fs)
+
+	_, errs := ctx.ParseBlueprintsFiles("Blueprints")
+	if len(errs) > 0 {
+		return ctx, errs
+	}
+
+	_, errs = ctx.PrepareBuildActions(config)
+	return ctx, errs
+}
+
+type mockProperties struct {
+	Vendor_available *bool
+
+	Vndk struct {
+		Enabled                *bool
+		Support_system_process *bool
+		Extends                *string
+	}
+
+	Product_variables struct {
+		Enforce_vintf_manifest struct {
+			Cflags []string
+		}
+
+		Treble_linker_namespaces struct {
+			Cflags []string
+		}
+	}
+}
+
+type mockCcLibraryModule struct {
+	ModuleBase
+	properties mockProperties
+}
+
+func newMockCcLibraryModule() Module {
+	m := &mockCcLibraryModule{}
+	m.AddProperties(&m.properties)
+	InitAndroidModule(m)
+	return m
+}
+
+func (p *mockCcLibraryModule) DepsMutator(ctx BottomUpMutatorContext) {
+}
+
+func (p *mockCcLibraryModule) GenerateAndroidBuildActions(ModuleContext) {
+}
diff --git a/android/testing.go b/android/testing.go
index 6e80c53..f5d33e1 100644
--- a/android/testing.go
+++ b/android/testing.go
@@ -17,6 +17,7 @@
 import (
 	"fmt"
 	"path/filepath"
+	"regexp"
 	"strings"
 	"testing"
 
@@ -163,3 +164,26 @@
 		t.FailNow()
 	}
 }
+
+func FailIfNoMatchingErrors(t *testing.T, pattern string, errs []error) {
+	t.Helper()
+
+	matcher, err := regexp.Compile(pattern)
+	if err != nil {
+		t.Errorf("failed to compile regular expression %q because %s", pattern, err)
+	}
+
+	found := false
+	for _, err := range errs {
+		if matcher.FindStringIndex(err.Error()) != nil {
+			found = true
+			break
+		}
+	}
+	if !found {
+		t.Errorf("missing the expected error %q (checked %d error(s))", pattern, len(errs))
+		for i, err := range errs {
+			t.Errorf("errs[%d] = %s", i, err)
+		}
+	}
+}
diff --git a/cc/cc_test.go b/cc/cc_test.go
index 6329605..2efee59 100644
--- a/cc/cc_test.go
+++ b/cc/cc_test.go
@@ -22,7 +22,6 @@
 	"io/ioutil"
 	"os"
 	"reflect"
-	"regexp"
 	"sort"
 	"strings"
 	"testing"
@@ -178,13 +177,13 @@
 
 	_, errs := ctx.ParseFileList(".", []string{"Android.bp"})
 	if len(errs) > 0 {
-		failIfNoMatchingErrors(t, pattern, errs)
+		android.FailIfNoMatchingErrors(t, pattern, errs)
 		return
 	}
 
 	_, errs = ctx.PrepareBuildActions(config)
 	if len(errs) > 0 {
-		failIfNoMatchingErrors(t, pattern, errs)
+		android.FailIfNoMatchingErrors(t, pattern, errs)
 		return
 	}
 
@@ -1064,29 +1063,6 @@
 	}
 }
 
-func failIfNoMatchingErrors(t *testing.T, pattern string, errs []error) {
-	matcher, err := regexp.Compile(pattern)
-	if err != nil {
-		t.Errorf("failed to compile regular expression %q because %s", pattern, err)
-	}
-
-	found := false
-
-	for _, err := range errs {
-		if matcher.FindStringIndex(err.Error()) != nil {
-			found = true
-			break
-		}
-	}
-
-	if !found {
-		t.Errorf("missing the expected error %q (checked %d error(s))", pattern, len(errs))
-		for i, err := range errs {
-			t.Errorf("errs[%d] = %s", i, err)
-		}
-	}
-}
-
 func getOutputPaths(ctx *android.TestContext, variant string, moduleNames []string) (paths android.Paths) {
 	for _, moduleName := range moduleNames {
 		module := ctx.ModuleForTests(moduleName, variant).Module().(*Module)