Add TestableResources (77f1b05f) · Commits · e / os / android_frameworks_base

tests/testables/src/android/testing/TestableContext.java

+30 −1

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		@@ -69,6 +69,7 @@ public class TestableContext extends ContextWrapper implements TestRule {
		private LeakCheck.Tracker mReceiver;
		private LeakCheck.Tracker mService;
		private LeakCheck.Tracker mComponent;
		private TestableResources mTestableResources;

		public TestableContext(Context base) {
		this(base, null);
		@@ -98,9 +99,37 @@ public class TestableContext extends ContextWrapper implements TestRule {
		return super.getPackageManager();
		}

		/**
		* Makes sure the resources being returned by this TestableContext are a version of
		* TestableResources.
		* @see #getResources()
		*/
		public void ensureTestableResources() {
		if (mTestableResources == null) {
		mTestableResources = new TestableResources(super.getResources());
		}
		}

		/**
		* Get (and create if necessary) {@link TestableResources} for this TestableContext.
		*/
		public TestableResources getOrCreateTestableResources() {
		ensureTestableResources();
		return mTestableResources;
		}

		/**
		* Returns a Resources instance for the test.
		*
		* By default this returns the same resources object that would come from the
		* {@link ContextWrapper}, but if {@link #ensureTestableResources()} or
		* {@link #getOrCreateTestableResources()} has been called, it will return resources gotten from
		* {@link TestableResources}.
		*/
		@Override
		public Resources getResources() {
		return super.getResources();
		return mTestableResources != null ? mTestableResources.getResources()
		: super.getResources();
		}

		public <T> void addMockSystemService(Class<T> service, T mock) {

tests/testables/src/android/testing/TestableResources.java

0 → 100644

+101 −0

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		/*
		* Copyright (C) 2017 The Android Open Source Project
		*
		* 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.testing;

		import static org.mockito.Mockito.mock;
		import static org.mockito.Mockito.withSettings;

		import android.content.Context;
		import android.content.res.Resources;
		import android.util.Log;
		import android.util.SparseArray;

		import org.mockito.invocation.InvocationOnMock;

		/**
		* Provides a version of Resources that defaults to all existing resources, but can have ids
		* changed to return specific values.
		* <p>
		* TestableResources are lazily initialized, be sure to call
		* {@link TestableContext#ensureTestableResources} before your tested code has an opportunity
		* to cache {@link Context#getResources}.
		* </p>
		*/
		public class TestableResources {

		private static final String TAG = "TestableResources";
		private final Resources mResources;
		private final SparseArray<Object> mOverrides = new SparseArray<>();

		TestableResources(Resources realResources) {
		mResources = mock(Resources.class, withSettings()
		.spiedInstance(realResources)
		.defaultAnswer(this::answer));
		}

		/**
		* Gets the implementation of Resources that will return overridden values when called.
		*/
		public Resources getResources() {
		return mResources;
		}

		/**
		* Sets the return value for the specified resource id.
		* <p>
		* Since resource ids are unique there is a single addOverride that will override the value
		* whenever it is gotten regardless of which method is used (i.e. getColor or getDrawable).
		* </p>
		* @param id The resource id to be overridden
		* @param value The value of the resource, null to cause a {@link Resources.NotFoundException}
		* when gotten.
		*/
		public void addOverride(int id, Object value) {
		mOverrides.put(id, value);
		}

		/**
		* Removes the override for the specified id.
		* <p>
		* This should be called over addOverride(id, null), because specifying a null value will
		* cause a {@link Resources.NotFoundException} whereas removing the override will actually
		* switch back to returning the default/real value of the resource.
		* </p>
		* @param id
		*/
		public void removeOverride(int id) {
		mOverrides.remove(id);
		}

		private Object answer(InvocationOnMock invocationOnMock) throws Throwable {
		try {
		int id = invocationOnMock.getArgument(0);
		int index = mOverrides.indexOfKey(id);
		if (index >= 0) {
		Object value = mOverrides.valueAt(index);
		if (value == null) throw new Resources.NotFoundException();
		return value;
		}
		} catch (Resources.NotFoundException e) {
		// Let through NotFoundException.
		throw e;
		} catch (Throwable t) {
		// Generic catching for the many things that can go wrong, fall back to
		// the real implementation.
		Log.i(TAG, "Falling back to default resources call " + t);
		}
		return invocationOnMock.callRealMethod();
		}
		}

tests/testables/tests/res/values/strings.xml

0 → 100644

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		<?xml version="1.0" encoding="utf-8"?>
		<!--
		/**
		* Copyright (c) 2009, The Android Open Source Project
		*
		* 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.
		*/
		-->
		<resources xmlns:xliff="urn:oasis:names:tc:xliff:document:1.2">
		<string name="test_string">This is a test string</string>
		</resources>

tests/testables/tests/src/android/testing/TestableResourcesTest.java

0 → 100644

+93 −0

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		/*
		* Copyright (C) 2017 The Android Open Source Project
		*
		* 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.testing;

		import static org.junit.Assert.assertEquals;
		import static org.junit.Assert.assertNotEquals;
		import static org.junit.Assert.assertNotNull;
		import static org.junit.Assert.assertNull;
		import static org.junit.Assert.fail;

		import android.content.res.Resources;
		import android.support.test.InstrumentationRegistry;

		import com.android.testables.R;

		import org.junit.Rule;
		import org.junit.Test;
		import org.junit.runner.RunWith;

		@RunWith(AndroidTestingRunner.class)
		public class TestableResourcesTest {

		@Rule
		public TestableContext mContext = new TestableContext(InstrumentationRegistry.getContext());

		@Test
		public void testLazyInit() {
		Resources before = mContext.getResources();
		mContext.ensureTestableResources();
		Resources after = mContext.getResources();
		assertNotEquals(before, after);
		}

		@Test
		public void testAddingResource() {
		final int nonExistentId = 3; // Ids don't go this low.

		try {
		mContext.getColor(nonExistentId);
		fail("Should throw NotFoundException");
		} catch (Resources.NotFoundException e) {
		}
		mContext.getOrCreateTestableResources().addOverride(nonExistentId, 0xffffff);

		assertEquals(0xffffff, mContext.getColor(nonExistentId));
		}

		@Test
		public void testClearingResource() {
		final int nonExistentId = 3; // Ids don't go this low.

		mContext.getOrCreateTestableResources().addOverride(nonExistentId, 0xffffff);
		assertEquals(0xffffff, mContext.getColor(nonExistentId));
		mContext.getOrCreateTestableResources().removeOverride(nonExistentId);
		try {
		mContext.getColor(nonExistentId);
		fail("Should throw NotFoundException");
		} catch (Resources.NotFoundException e) {
		}
		}

		@Test
		public void testOverrideExisting() {
		int existentId = R.string.test_string;

		assertNotNull(mContext.getString(existentId));
		mContext.getOrCreateTestableResources().addOverride(existentId, "Other strings");

		assertEquals("Other strings", mContext.getString(existentId));
		}

		@Test(expected = Resources.NotFoundException.class)
		public void testNonExistentException() {
		int existentId = R.string.test_string;

		assertNotNull(mContext.getString(existentId));
		mContext.getOrCreateTestableResources().addOverride(existentId, null);

		assertNull(mContext.getString(existentId));
		}
		}
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