1 /* 2 * Copyright 2017, OpenCensus Authors 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 io.opencensus.common; 18 19 import static com.google.common.truth.Truth.assertThat; 20 21 import org.junit.Rule; 22 import org.junit.Test; 23 import org.junit.rules.ExpectedException; 24 import org.junit.runner.RunWith; 25 import org.junit.runners.JUnit4; 26 27 /** Tests for {@link Functions}. */ 28 @RunWith(JUnit4.class) 29 public class FunctionsTest { 30 @Rule public ExpectedException thrown = ExpectedException.none(); 31 32 @Test testReturnNull()33 public void testReturnNull() { 34 assertThat(Functions.returnNull().apply("ignored")).isNull(); 35 } 36 37 @Test testReturnConstant()38 public void testReturnConstant() { 39 assertThat(Functions.returnConstant(123).apply("ignored")).isEqualTo(123); 40 } 41 42 @Test testReturnToString()43 public void testReturnToString() { 44 assertThat(Functions.returnToString().apply("input")).isEqualTo("input"); 45 assertThat(Functions.returnToString().apply(Boolean.FALSE)).isEqualTo("false"); 46 assertThat(Functions.returnToString().apply(Double.valueOf(123.45))).isEqualTo("123.45"); 47 assertThat(Functions.returnToString().apply(null)).isEqualTo(null); 48 } 49 50 @Test testThrowIllegalArgumentException()51 public void testThrowIllegalArgumentException() { 52 Function<Object, Void> f = Functions.throwIllegalArgumentException(); 53 thrown.expect(IllegalArgumentException.class); 54 f.apply("ignored"); 55 } 56 57 @Test testThrowAssertionError()58 public void testThrowAssertionError() { 59 Function<Object, Void> f = Functions.throwAssertionError(); 60 thrown.handleAssertionErrors(); 61 thrown.expect(AssertionError.class); 62 f.apply("ignored"); 63 } 64 } 65