luni/src/test/java/libcore/java/lang/StackWalkerTest.java

/*
 * Copyright (C) 2022 The Android Open Source Project
 *
 * Licensed 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
 *
 *      http://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 libcore.java.lang;

import org.junit.Assert;
import org.junit.Test;
import org.junit.runner.RunWith;
import org.junit.runners.JUnit4;

import java.io.IOException;
import java.io.InputStream;
import java.lang.StackWalker.Option;
import java.lang.StackWalker.StackFrame;
import java.nio.ByteBuffer;
import java.util.Arrays;
import java.util.List;
import libcore.io.Streams;

import dalvik.system.InMemoryDexClassLoader;

import static org.junit.Assert.assertEquals;
import static org.junit.Assert.assertSame;
import static org.junit.Assert.assertTrue;
import static org.junit.Assert.fail;

@RunWith(JUnit4.class)
public class StackWalkerTest {

    @Test
    public void testGetByteCodeIndex() throws Exception {
        ClassLoader classLoader = loadPrebuiltDexClassLoader();
        // See source at libcore/luni/src/test/dex_src/libcore/java/lang/stackwalker/Test1.java
        Class test1Class = classLoader.loadClass("libcore.java.lang.stackwalker.Test1");
        List<StackFrame> stackFrames = (List<StackFrame>) test1Class.getMethod("test")
                .invoke(null);
        assertTrue(stackFrames.size() >= 3);

        StackFrame f = stackFrames.get(0);
        assertEquals(test1Class.getName(), f.getClassName());
        assertEquals("invokeWalker", f.getMethodName());
        assertEquals(32, f.getLineNumber());
        // The getByteCodeIndex() result can be checked against
        // `dexdump -d libcore/luni/src/test/resources/prebuilt-dex-from-java.dex`
        assertEquals(9, f.getByteCodeIndex());

        f = stackFrames.get(1);
        assertEquals(test1Class.getName(), f.getClassName());
        assertEquals("test", f.getMethodName());
        assertEquals(26, f.getLineNumber());
        assertEquals(0, f.getByteCodeIndex());

        f = stackFrames.get(2);
        assertEquals(StackWalkerTest.class.getName(), f.getClassName());
        assertEquals("testGetByteCodeIndex", f.getMethodName());
    }


    private static ClassLoader loadPrebuiltDexClassLoader() throws IOException {
        // See "core-tests-prebuilt-dex-from-java" in JavaLibrary.bp to re-generate this dex file.
        try (InputStream is = ThreadTest.class.getClassLoader()
                .getResourceAsStream("prebuilt-dex-from-java.dex")) {
            byte[] data = Streams.readFullyNoClose(is);
            return new InMemoryDexClassLoader(ByteBuffer.wrap(data),
                    ThreadTest.class.getClassLoader());
        }
    }

    @Test
    public void testOptionValueOf() {
        assertSame(Option.RETAIN_CLASS_REFERENCE, Option.valueOf("RETAIN_CLASS_REFERENCE"));
        assertSame(Option.SHOW_REFLECT_FRAMES, Option.valueOf("SHOW_REFLECT_FRAMES"));
        assertSame(Option.SHOW_HIDDEN_FRAMES, Option.valueOf("SHOW_HIDDEN_FRAMES"));
    }

    @Test
    public void testOptionValues() {
        Option[] options = Option.values();
        Option[] expected = new Option[] {
                Option.RETAIN_CLASS_REFERENCE,
                Option.SHOW_REFLECT_FRAMES,
                Option.SHOW_HIDDEN_FRAMES,
        };
        for (Option e : expected) {
            assertHasOption(options, e);
        }
        assertEquals(expected.length, options.length);
    }

    private void assertHasOption(Option[] options, Option expected) {
        for (Option option : options) {
            if (option == expected) {
                return;
            }
        }
        fail("fail to find " + expected + " in " + Arrays.toString(options));
    }

}