1 /* 2 * Copyright (C) 2019 The Android Open Source Project 3 * 4 * Licensed under the Apache License, Version 2.0 (the "License"); 5 * you may not use this file except in compliance with the License. 6 * You may obtain a copy of the License at 7 * 8 * http://www.apache.org/licenses/LICENSE-2.0 9 * 10 * Unless required by applicable law or agreed to in writing, software 11 * distributed under the License is distributed on an "AS IS" BASIS, 12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 13 * See the License for the specific language governing permissions and 14 * limitations under the License. 15 */ 16 17 package libcore.junit.util.compat; 18 19 import android.compat.Compatibility; 20 import android.compat.Compatibility.ChangeConfig; 21 22 import org.junit.rules.TestRule; 23 import org.junit.runner.Description; 24 import org.junit.runners.model.Statement; 25 26 import java.lang.annotation.ElementType; 27 import java.lang.annotation.Retention; 28 import java.lang.annotation.RetentionPolicy; 29 import java.lang.annotation.Target; 30 import java.util.HashSet; 31 import java.util.Set; 32 import com.google.common.primitives.Longs; 33 34 /** 35 * Allows tests to specify the which change to disable. 36 * 37 * <p>To use add the following to the test class. It will only change the behavior of a test method 38 * if it is annotated with {@link EnableCompatChanges} and/or {@link DisableCompatChanges}. 39 * 40 * <pre> 41 * @Rule 42 * public TestRule compatChangeRule = new CoreCompatChangeRule(); 43 * </pre> 44 * 45 * <p>Each test method that needs to disable a specific change needs to be annotated 46 * with {@link EnableCompatChanges} and/or {@link DisableCompatChanges} specifying the change id. 47 * e.g.: 48 * 49 * <pre> 50 * @Test 51 * @DisableCompatChanges({42}) 52 * public void testAsIfChange42Disabled() { 53 * // check behavior 54 * } 55 * 56 * @Test 57 * @EnableCompatChanges({42}) 58 * public void testAsIfChange42Enabled() { 59 * // check behavior 60 * 61 * </pre> 62 */ 63 public class CoreCompatChangeRule implements TestRule { 64 65 @Override apply(final Statement statement, Description description)66 public Statement apply(final Statement statement, Description description) { 67 Set<Long> enabled = new HashSet<>(); 68 Set<Long> disabled = new HashSet<>(); 69 EnableCompatChanges enableCompatChanges = description.getAnnotation( 70 EnableCompatChanges.class); 71 DisableCompatChanges disableCompatChanges = description.getAnnotation( 72 DisableCompatChanges.class); 73 if (enableCompatChanges != null) { 74 enabled.addAll(Longs.asList(enableCompatChanges.value())); 75 } 76 if (disableCompatChanges != null) { 77 disabled.addAll(Longs.asList(disableCompatChanges.value())); 78 } 79 ChangeConfig config = new ChangeConfig(enabled, disabled); 80 if (config.isEmpty()) { 81 return statement; 82 } else { 83 return createStatementForConfig(statement, config); 84 } 85 } 86 createStatementForConfig(final Statement statement, ChangeConfig config)87 protected Statement createStatementForConfig(final Statement statement, ChangeConfig config) { 88 return new CompatChangeStatement(statement, config); 89 } 90 91 private static class CompatChangeStatement extends Statement { 92 private final Statement testStatement; 93 private final ChangeConfig config; 94 CompatChangeStatement(Statement testStatement, ChangeConfig config)95 private CompatChangeStatement(Statement testStatement, ChangeConfig config) { 96 this.testStatement = testStatement; 97 this.config = config; 98 } 99 100 @Override evaluate()101 public void evaluate() throws Throwable { 102 Compatibility.setOverrides(config); 103 try { 104 testStatement.evaluate(); 105 } finally { 106 Compatibility.clearOverrides(); 107 } 108 } 109 } 110 111 @Retention(RetentionPolicy.RUNTIME) 112 @Target(ElementType.METHOD) 113 public @interface EnableCompatChanges { value()114 long[] value(); 115 } 116 117 @Retention(RetentionPolicy.RUNTIME) 118 @Target(ElementType.METHOD) 119 public @interface DisableCompatChanges { value()120 long[] value(); 121 } 122 } 123