/*
    * 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.xml.secure;
  
  import static org.junit.jupiter.api.Assertions.assertEquals;
  import static org.junit.jupiter.api.Assertions.assertInstanceOf;
  import static org.junit.jupiter.api.Assertions.assertNotNull;
  import static org.junit.jupiter.api.Assertions.assertNull;
  import static org.junit.jupiter.api.Assertions.assertSame;
  import static org.junit.jupiter.api.Assertions.assertThrows;
  
  import java.lang.invoke.MethodHandle;
  
  import javax.xml.parsers.FactoryConfigurationError;
  import javax.xml.stream.XMLInputFactory;
  
  import org.junit.jupiter.api.Test;
  
  /**
   * Tests for {@link MethodHandleFactory}, the reflective lookup helper behind {@link SecureXMLInputFactory#newDefaultFactory()}.
   * <p>
   * The helper is exercised directly, including the miss and rethrow paths that no standard JVM factory lookup reaches, so the platform-specific fallback logic
   * of the secure factory has full branch coverage.
   * </p>
   */
  class MethodHandleFactoryTest {
  
      @Test
      void findStaticReturnsHandleForExistingMethod() {
          final MethodHandle handle = MethodHandleFactory.findStatic(XMLInputFactory.class, "newInstance");
          assertNotNull(handle, "an existing static method must resolve to a handle");
      }
  
      @Test
      void findStaticReturnsNullForMissingMethod() {
          assertNull(MethodHandleFactory.findStatic(XMLInputFactory.class, "noSuchMethod"),
                  "a missing method must resolve to null");
      }
  
      @Test
      void invokeExactRethrowsDeclaredException() {
          final FactoryConfigurationError declared = new FactoryConfigurationError("boom");
          final FactoryConfigurationError thrown = assertThrows(FactoryConfigurationError.class, () -> MethodHandleFactory.invokeExact(() -> {
              throw declared;
          }, FactoryConfigurationError.class), "an exception of the declared type must be rethrown");
          assertSame(declared, thrown, "the declared exception must propagate unchanged");
      }
  
      @Test
      void invokeExactRethrowsUndeclaredError() {
          final OutOfMemoryError error = new OutOfMemoryError("boom");
          final OutOfMemoryError thrown = assertThrows(OutOfMemoryError.class, () -> MethodHandleFactory.invokeExact(() -> {
              throw error;
          }, FactoryConfigurationError.class), "a JVM error must keep its type");
          assertSame(error, thrown, "the error must propagate unchanged");
      }
  
      @Test
      void invokeExactReturnsValue() {
          assertEquals("value", MethodHandleFactory.invokeExact(() -> "value", IllegalStateException.class), "the callable's value must be returned");
      }
  
      @Test
      void invokeExactWrapsUnexpectedException() {
          final IllegalStateException wrapped = assertThrows(IllegalStateException.class, () -> MethodHandleFactory.invokeExact(() -> {
              throw new IllegalArgumentException("boom");
          }, FactoryConfigurationError.class), "an undeclared exception must be wrapped");
          assertInstanceOf(IllegalArgumentException.class, wrapped.getCause(), "the unexpected exception must be the wrapper's cause");
      }
  }