org.jacoco.core.instr.ResizeInstructionsTest.java Source code

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Here is the source code for org.jacoco.core.instr.ResizeInstructionsTest.java

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/*******************************************************************************
 * Copyright (c) 2009, 2019 Mountainminds GmbH & Co. KG and Contributors
 * This program and the accompanying materials are made available under
 * the terms of the Eclipse Public License 2.0 which is available at
 * http://www.eclipse.org/legal/epl-2.0
 *
 * SPDX-License-Identifier: EPL-2.0
 *
 * Contributors:
 *    Evgeny Mandrikov - initial API and implementation
 *
 *******************************************************************************/
package org.jacoco.core.instr;

import static org.junit.Assert.assertNotNull;
import static org.junit.Assert.assertSame;
import static org.junit.Assert.assertTrue;

import org.jacoco.core.internal.instr.InstrSupport;
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.ClassReader;
import org.objectweb.asm.ClassVisitor;
import org.objectweb.asm.ClassWriter;
import org.objectweb.asm.Label;
import org.objectweb.asm.MethodVisitor;
import org.objectweb.asm.Opcodes;

public class ResizeInstructionsTest {

    private IRuntime runtime;
    private Instrumenter instrumenter;

    private boolean computedCommonSuperClass;

    @Before
    public void setup() throws Exception {
        runtime = new SystemPropertiesRuntime();
        instrumenter = new Instrumenter(runtime);
        runtime.startup(new RuntimeData());
        computedCommonSuperClass = false;
    }

    @After
    public void teardown() {
        runtime.shutdown();
    }

    private class Inner {
    }

    /**
     * Test of ASM bug
     * <a href="https://gitlab.ow2.org/asm/asm/issues/317792">#317792</a>.
     */
    @Test
    public void should_not_loose_InnerClasses_attribute() throws Exception {
        byte[] source = TargetLoader.getClassDataAsBytes(Inner.class);

        final ClassReader cr = InstrSupport.classReaderFor(source);
        final ClassWriter cw = new ClassWriter(0);
        cr.accept(new ClassVisitor(InstrSupport.ASM_API_VERSION, cw) {
            @Override
            public void visitEnd() {
                final MethodVisitor mv = cv.visitMethod(0, "m", "()V", null, null);
                mv.visitCode();
                addCauseOfResizeInstructions(mv);
                mv.visitInsn(Opcodes.NOP);
                mv.visitMaxs(2, 1);
                mv.visitEnd();
                super.visitEnd();
            }
        }, 0);
        source = cw.toByteArray();

        final byte[] bytes = instrumenter.instrument(source, "");

        final TargetLoader targetLoader = new TargetLoader();
        final Class<?> outer = targetLoader.add(ResizeInstructionsTest.class,
                TargetLoader.getClassDataAsBytes(ResizeInstructionsTest.class));
        final Class<?> inner = targetLoader.add(Inner.class, bytes);
        assertSame(outer, inner.getEnclosingClass());
        assertNotNull(inner.getEnclosingClass());
        assertSame(outer, inner.getDeclaringClass());
        assertNotNull(inner.getDeclaringClass());
    }

    /**
     * Test of ASM bug
     * <a href= "https://gitlab.ow2.org/asm/asm/issues/317630">#317630</a> that
     * caused {@code java.lang.ClassNotFoundException}.
     */
    @Test
    public void should_not_require_computation_of_common_superclass() throws Exception {
        final String className = "Example";

        final ClassWriter cw = new ClassWriter(ClassWriter.COMPUTE_FRAMES) {
            @Override
            protected String getCommonSuperClass(final String type1, final String type2) {
                computedCommonSuperClass |= className.equals(type1) || className.equals(type2);
                return "java/lang/Object";
            }
        };
        cw.visit(Opcodes.V1_5, Opcodes.ACC_PUBLIC, className, null, "java/lang/Object", null);
        final MethodVisitor mv = cw.visitMethod(Opcodes.ACC_PUBLIC, "m", "()V", null, null);
        mv.visitCode();
        addCauseOfResizeInstructions(mv);
        addCauseOfGetCommonSuperClass(mv);
        mv.visitMaxs(1, 1);
        mv.visitEnd();
        cw.visitEnd();
        final byte[] original = cw.toByteArray();
        assertTrue(computedCommonSuperClass);
        new TargetLoader().add(className, original);

        final byte[] instrumented = instrumenter.instrument(original, className);
        new TargetLoader().add(className, instrumented);
    }

    /**
     * Adds code that requires
     * {@link ClassWriter#getCommonSuperClass(String, String)}.
     *
     * <pre>
     * Object o = this;
     * while (true) {
     *    o = (Integer) null;
     * }
     * </pre>
     */
    private static void addCauseOfGetCommonSuperClass(final MethodVisitor mv) {
        mv.visitVarInsn(Opcodes.ALOAD, 0);
        mv.visitVarInsn(Opcodes.ASTORE, 1);
        Label label = new Label();
        mv.visitLabel(label);
        mv.visitInsn(Opcodes.ACONST_NULL);
        mv.visitTypeInsn(Opcodes.CHECKCAST, "java/lang/Integer");
        mv.visitVarInsn(Opcodes.ASTORE, 1);
        mv.visitJumpInsn(Opcodes.GOTO, label);
    }

    /**
     * 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);
    }

}