1 /*
2  * Copyright (C) 2016 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 com.android.documentsui.testing;
18 
19 import static org.junit.Assert.assertEquals;
20 import static org.junit.Assert.assertTrue;
21 
22 import java.util.concurrent.CompletableFuture;
23 import java.util.concurrent.ExecutionException;
24 import java.util.concurrent.TimeUnit;
25 import java.util.concurrent.TimeoutException;
26 import java.util.function.Predicate;
27 
28 import javax.annotation.Nullable;
29 
30 /**
31  * Test {@link Predicate} that can be used to spy on,  control responses from,
32  * and make assertions against values tested.
33  */
34 public class TestPredicate<T> implements Predicate<T> {
35 
36     private final CompletableFuture<T> mFuture = new CompletableFuture<>();
37     private @Nullable T mLastValue;
38     private boolean mNextReturnValue;
39     private boolean mCalled;
40 
41     @Override
test(T t)42     public boolean test(T t) {
43         mCalled = true;
44         mLastValue = t;
45         mFuture.complete(t);
46         return mNextReturnValue;
47     }
48 
assertLastArgument(@ullable T expected)49     public void assertLastArgument(@Nullable T expected) {
50         assertEquals(expected, mLastValue);
51     }
52 
assertCalled()53     public void assertCalled() {
54         assertTrue(mCalled);
55     }
56 
nextReturn(boolean value)57     public void nextReturn(boolean value) {
58         mNextReturnValue = value;
59     }
60 
waitForCall(int timeout, TimeUnit unit)61     public @Nullable T waitForCall(int timeout, TimeUnit unit)
62             throws InterruptedException, ExecutionException, TimeoutException {
63         return mFuture.get(timeout, unit);
64     }
65 }
66