content: /*******************************************************************************
   * Copyright (c) 2009, 2019 Mountainminds GmbH & Co. KG and Contributors
   * All rights reserved. This program and the accompanying materials
   * are made available under the terms of the Eclipse Public License v1.0
   * which accompanies this distribution, and is available at
   * http://www.eclipse.org/legal/epl-v10.html
   *
   * Contributors:
   *    Evgeny Mandrikov - initial API and implementation
   *
   *******************************************************************************/
  package org.jacoco.core.test.validation.java8;
  
  import static org.junit.Assert.assertEquals;
  
  import java.lang.invoke.CallSite;
  import java.lang.invoke.ConstantCallSite;
  import java.lang.invoke.MethodHandles;
  import java.lang.invoke.MethodType;
  import java.lang.reflect.InvocationTargetException;
  
  import org.jacoco.core.instr.Instrumenter;
  import org.jacoco.core.runtime.IRuntime;
  import org.jacoco.core.runtime.RuntimeData;
  import org.jacoco.core.runtime.SystemPropertiesRuntime;
  import org.jacoco.core.test.TargetLoader;
  import org.junit.After;
  import org.junit.Before;
  import org.junit.Test;
  import org.objectweb.asm.ClassWriter;
  import org.objectweb.asm.Handle;
  import org.objectweb.asm.Label;
  import org.objectweb.asm.MethodVisitor;
  import org.objectweb.asm.Opcodes;
  
  /**
   * Test of ASM bug
   * <a href="https://gitlab.ow2.org/asm/asm/issues/317748">#317748</a> that
   * caused
   * {@code java.lang.ClassFormatError: Short length on BootstrapMethods in class file}
   * during instrumentation.
   */
  public class BootstrapMethodReferenceTest {
  
  	private IRuntime runtime;
  	private Instrumenter instrumenter;
  
  	@Before
  	public void setup() throws Exception {
  		runtime = new SystemPropertiesRuntime();
  		instrumenter = new Instrumenter(runtime);
  		runtime.startup(new RuntimeData());
  	}
  
  	@After
  	public void teardown() {
  		runtime.shutdown();
  	}
  
  	@Test
  	public void test() throws Exception {
  		final String className = "Example";
  
  		final ClassWriter cw = new ClassWriter(ClassWriter.COMPUTE_FRAMES);
  		cw.visit(Opcodes.V1_7, Opcodes.ACC_PUBLIC, className, null,
  				"java/lang/Object", null);
  
  		final MethodVisitor mv = cw.visitMethod(
  				Opcodes.ACC_PUBLIC | Opcodes.ACC_STATIC, "run", "()I", null,
  				null);
  		mv.visitCode();
  		addCauseOfResizeInstructions(mv);
  		final MethodType methodType = MethodType.methodType(CallSite.class,
  				MethodHandles.Lookup.class, String.class, MethodType.class);
  		final Handle handle = new Handle(Opcodes.H_INVOKESTATIC,
  				this.getClass().getCanonicalName().replace('.', '/'),
  				"bootstrap", methodType.toMethodDescriptorString(), false);
  		mv.visitInvokeDynamicInsn("invoke", "()I", handle);
  		mv.visitInsn(Opcodes.IRETURN);
  		mv.visitMaxs(1, 0);
  		mv.visitEnd();
  
  		cw.visitEnd();
  
  		final byte[] original = cw.toByteArray();
  		assertEquals(42, run(className, original));
  
  		final byte[] instrumented = instrumenter.instrument(original,
  				className);
  		assertEquals(42, run(className, instrumented));
  	}
  
  	private static int run(final String className, final byte[] bytes)
  			throws ClassNotFoundException, NoSuchMethodException,
  			InvocationTargetException, IllegalAccessException {
  		final Integer result = (Integer) new TargetLoader()
  				.add(className, bytes).getMethod("run").invoke(null);
  		return result.intValue();
  	}
  
  	/**
  	 * Adds code that triggers usage of
  	 * {@link org.objectweb.asm.MethodWriter#COMPUTE_INSERTED_FRAMES} during
  	 * instrumentation.
  	 */
  	private static void addCauseOfResizeInstructions(final MethodVisitor mv) {
  		mv.visitInsn(Opcodes.ICONST_0);
  		mv.visitInsn(Opcodes.ICONST_1);
  		final Label target = new Label();
  		mv.visitJumpInsn(Opcodes.IFLE, target);
  		for (int i = 0; i < Short.MAX_VALUE; i++) {
  			mv.visitInsn(Opcodes.NOP);
  		}
  		mv.visitLabel(target);
  	}
  
  	public static CallSite bootstrap(final MethodHandles.Lookup caller,
  			final String name, final MethodType type) throws Exception {
  		return new ConstantCallSite(
  				caller.findStatic(BootstrapMethodReferenceTest.class,
  						"callTarget", MethodType.methodType(int.class)));
  	}
  
  	public static int callTarget() {
  		return 42;
  	}
  
  }
  