InvokeMainIT.java

package edu.pdx.cs410J;

import org.junit.Test;

import static org.hamcrest.CoreMatchers.equalTo;
import static org.hamcrest.MatcherAssert.assertThat;
import static org.junit.Assert.assertEquals;
import static org.junit.Assert.assertNull;

/**
 * Tests the {@link #invokeMain(Class, String[])} method of {@link InvokeMainTestCase}
 */
public class InvokeMainIT extends InvokeMainTestCase {

    @Test
    public void testNoExitCode() {
        MainMethodResult result = invokeMain( NoExitCode.class );
        assertNull( result.getExitCode() );
    }

    @Test
    public void testZeroExitCode() {
        MainMethodResult result = invokeMain( ZeroExitCode.class );
        assertEquals(new Integer(0), result.getExitCode());
    }

    @Test
    public void testExitCodeOf1() {
        MainMethodResult result = invokeMain( ExitCodeOf1.class );
        assertEquals(new Integer(1), result.getExitCode());
    }

    @Test
    public void testCommandLineArguments() {
        Integer exitCode = 27;
        MainMethodResult result = invokeMain( ExitCodeFromCommandLine.class, String.valueOf(exitCode) );
        assertEquals( exitCode, result.getExitCode() );
    }

    @Test
    public void testStandardOutput() {
        MainMethodResult result = invokeMain( WriteArgsToStandardOut.class, "1", "2", "3", "4", "5" );
        assertEquals( "12345", result.getOut() );
    }

    @Test
    public void testStandardError() {
        MainMethodResult result = invokeMain( WriteArgsToStandardErr.class, "1", "2", "3", "4", "5" );
        assertEquals( "12345", result.getErr() );
    }

  @Test
  public void codeAfterSystemExitIsNotExecuted() {
    MainMethodResult result = invokeMain(CodeAfterSystemExit.class);
    assertThat(result.getExitCode(), equalTo(1));
    assertThat(result.getOut(), equalTo(""));
  }

    private static class NoExitCode
    {
        public static void main(String... args) {
            // Doesn't invoke System.exit()
        }
    }

    private static class ZeroExitCode
    {
        public static void main(String... args) {
            System.exit(0);
        }
    }

    private static class ExitCodeOf1
    {
        public static void main(String... args) {
            System.exit(1);
        }
    }

    private static class ExitCodeFromCommandLine
    {
        public static void main(String... args)
        {
            System.exit(Integer.parseInt(args[0]));
        }
    }

    private static class WriteArgsToStandardOut
    {
        public static void main(String... args) {
            for (String arg : args) {
                System.out.print(arg);
            }
            System.out.flush();
        }
    }

    private static class WriteArgsToStandardErr
    {
        public static void main(String... args) {
            for (String arg : args) {
                System.err.print(arg);
            }
            System.err.flush();
        }
    }

  private static class CodeAfterSystemExit {
    public static void main(String... args) {
      callSystemExit1();
      System.out.println("Should not get here");
      throw new RuntimeException("Should not get here");
    }

    private static void callSystemExit1() {
      System.exit(1);
    }
  }
}