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 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.

 *

 * This code is free software; you can redistribute it and/or modify it

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 *

 * This code is distributed in the hope that it will be useful, but WITHOUT

 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or

 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License

 * version 2 for more details (a copy is included in the LICENSE file that

 * accompanied this code).

 *

 * You should have received a copy of the GNU General Public License version

 * 2 along with this work; if not, write to the Free Software Foundation,

 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.

 *

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/*

 * @test

 * @bug 8171385

 * @summary Test JShell#stop

 * @modules jdk.jshell/jdk.internal.jshell.tool

 * @build KullaTesting TestingInputStream

 * @run testng StopExecutionTest

 */

import java.io.IOException;

import java.io.PipedInputStream;

import java.io.PipedOutputStream;

import java.io.PrintWriter;

import java.io.StringWriter;

import java.util.Random;

import java.util.concurrent.CountDownLatch;

import java.util.function.Consumer;

import jdk.internal.jshell.tool.StopDetectingInputStream;

import jdk.internal.jshell.tool.StopDetectingInputStream.State;

import jdk.jshell.JShell;

import org.testng.annotations.Test;

import static org.testng.Assert.assertEquals;

import static org.testng.Assert.fail;

@Test

public class StopExecutionTest extends KullaTesting {

    private final Object lock = new Object();

    private boolean isStopped;

    @Test(enabled = false) // TODO 8129546

    public void testStopLoop() throws InterruptedException {

        scheduleStop("while (true) ;");

    }

    @Test(enabled = false) // TODO 8129546

    public void testStopASleep() throws InterruptedException {

        scheduleStop("while (true) { try { Thread.sleep(100); } catch (InterruptedException ex) { } }");

    }

    @Test(enabled = false) // TODO 8129546

    public void testScriptCatchesStop() throws Exception {

        scheduleStop("for (int i = 0; i < 30; i++) { try { Thread.sleep(100); } catch (Throwable ex) { } }");

    }

    private void scheduleStop(String src) throws InterruptedException {

        JShell state = getState();

        isStopped = false;

        StringWriter writer = new StringWriter();

        PrintWriter out = new PrintWriter(writer);

        Thread t = new Thread(() -> {

            int i = 1;

            int n = 30;

            synchronized (lock) {

                do {

                    state.stop();

                    if (!isStopped) {

                        out.println("Not stopped. Try again: " + i);

                        try {

                            lock.wait(1000);

                        } catch (InterruptedException ignored) {

                        }

                    }

                } while (i++ < n && !isStopped);

                if (!isStopped) {

                    System.err.println(writer.toString());

                    fail("Evaluation was not stopped: '" + src + "'");

                }

            }

        });

        t.start();

        assertEval(src);

        synchronized (lock) {

            out.println("Evaluation was stopped successfully: '" + src + "'");

            isStopped = true;

            lock.notify();

        }

        // wait until the background thread finishes to prevent from calling 'stop' on closed state.

        t.join();

    }

    public void testStopDetectingInputRandom() throws IOException {

        long seed = System.nanoTime();

        Random r = new Random(seed);

        for (int m = 0; m < 10; m++) {

            StopDetectingInputStream buffer = new StopDetectingInputStream(null, null);

            buffer.setState(State.BUFFER);

            for (int i = 0; i < 1000; i++) {

                int chunkSize = r.nextInt(StopDetectingInputStream.INITIAL_SIZE * 3);

                doChunk(buffer, chunkSize);

            }

        }

    }

    private void doChunk(StopDetectingInputStream buffer, int chunkSize) throws IOException {

        for (int c = 0; c < chunkSize; c++) {

            buffer.write(c);

        }

        for (int c = 0; c < chunkSize; c++) {

            int read = buffer.read();

            assertEquals(read, c);

        }

    }

    public void testStopDetectingInputBufferWaitStop() throws Exception {

        Runnable shouldNotHappenRun =

                () -> { throw new AssertionError("Should not happen."); };

        Consumer<Exception> shouldNotHappenExc =

                exc -> { throw new AssertionError("Should not happen.", exc); };

        StopDetectingInputStream sd = new StopDetectingInputStream(shouldNotHappenRun, shouldNotHappenExc);

        CountDownLatch reading = new CountDownLatch(1);

        PipedInputStream is = new PipedInputStream() {

            @Override

            public int read() throws IOException {

                reading.countDown();

                return super.read();

            }

        };

        PipedOutputStream os = new PipedOutputStream(is);

        sd.setInputStream(is);

        sd.setState(State.BUFFER);

        reading.await();

        sd.setState(State.WAIT);

        os.write(3);

        int value = sd.read();

        if (value != 3) {

            throw new AssertionError();

        }

    }

}