/*
    * Licensed to the Apache Software Foundation (ASF) under one or more
    * contributor license agreements.  See the NOTICE file distributed with
    * this work for additional information regarding copyright ownership.
    * The ASF licenses this file to You 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
    *
    *      https://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 org.apache.commons.lang3.function;
  
  import static org.apache.commons.lang3.LangAssertions.assertNullPointerException;
  import static org.junit.jupiter.api.Assertions.assertEquals;
  import static org.junit.jupiter.api.Assertions.assertNotNull;
  import static org.junit.jupiter.api.Assertions.assertNull;
  import static org.junit.jupiter.api.Assertions.assertThrows;
  
  import java.io.IOException;
  
  import org.apache.commons.lang3.AbstractLangTest;
  import org.junit.jupiter.api.Test;
  
  /**
   * Tests {@link FailableBiFunction}.
   */
  class FailableBiFunctionTest extends AbstractLangTest {
  
      @Test
      void testAndThen_composesCorrectly() throws IOException {
          final FailableBiFunction<Integer, Integer, Integer, IOException> sum = (a, b) -> a + b;
          final FailableFunction<Integer, String, IOException> toStr = i -> "result:" + i;
          assertEquals("result:3", sum.andThen(toStr).apply(1, 2));
      }
  
      @Test
      void testAndThen_firstThrows_secondNotInvoked() {
          final IOException expected = new IOException("first");
          final FailableBiFunction<String, String, String, IOException> f = (a, b) -> {
              throw expected;
          };
          final FailableFunction<String, String, IOException> after = s -> s + "!";
          final IOException thrown = assertThrows(IOException.class, () -> f.andThen(after).apply("a", "b"));
          assertEquals(expected, thrown);
      }
  
      @Test
      void testAndThen_nullAfter_throwsNullPointerException() throws Throwable {
          final FailableBiFunction<String, String, String, IOException> f = (a, b) -> a + b;
          assertNullPointerException(() -> f.andThen(null));
      }
  
      @Test
      void testApply_returnsResult() throws IOException {
          final FailableBiFunction<String, String, String, IOException> f = (a, b) -> a + b;
          assertEquals("ab", f.apply("a", "b"));
      }
  
      @Test
      void testApply_throwsException() {
          final IOException expected = new IOException("fail");
          final FailableBiFunction<String, String, String, IOException> f = (a, b) -> {
              throw expected;
          };
          final IOException thrown = assertThrows(IOException.class, () -> f.apply("a", "b"));
          assertEquals(expected, thrown);
      }
  
      @Test
      void testNop_applyReturnsNull() throws Throwable {
          assertNull(FailableBiFunction.nop().apply("a", "b"));
      }
  
      @Test
      void testNop_returnsNonNull() {
          assertNotNull(FailableBiFunction.nop());
      }
  }