textfeedbacktest.java

JUnit, java testing tool

package junit.tests.runner;

import java.io.ByteArrayOutputStream;
import java.io.OutputStream;
import java.io.PrintStream;

import junit.framework.AssertionFailedError;
import junit.framework.TestCase;
import junit.framework.TestResult;
import junit.framework.TestSuite;
import junit.textui.ResultPrinter;
import junit.textui.TestRunner;

public class TextFeedbackTest extends TestCase {
	OutputStream output;
	TestRunner runner;
	
	static class TestResultPrinter extends ResultPrinter {
		TestResultPrinter(PrintStream writer) {
			super(writer);
		}
		
		/* Spoof printing time so the tests are deterministic
		 */
		@Override
		protected String elapsedTimeAsString(long runTime) {
			return "0";
		}
	}
	
	public static void main(String[] args) {
		TestRunner.run(TextFeedbackTest.class);
	}
	
	@Override
	public void setUp() {
		output= new ByteArrayOutputStream();
		runner= new TestRunner(new TestResultPrinter(new PrintStream(output)));
	}
	
	public void testEmptySuite() {
		String expected= expected(new String[]{"", "Time: 0", "", "OK (0 tests)", ""});
		runner.doRun(new TestSuite());
		assertEquals(expected, output.toString());
	}

	
	public void testOneTest() {
		String expected= expected(new String[]{".", "Time: 0", "", "OK (1 test)", ""});
		TestSuite suite = new TestSuite();
		suite.addTest(new TestCase() { @Override
		public void runTest() {}});
		runner.doRun(suite);
		assertEquals(expected, output.toString());
	}
	
	public void testTwoTests() {
		String expected= expected(new String[]{"..", "Time: 0", "", "OK (2 tests)", ""});
		TestSuite suite = new TestSuite();
		suite.addTest(new TestCase() { @Override
		public void runTest() {}});
		suite.addTest(new TestCase() { @Override
		public void runTest() {}});
		runner.doRun(suite);
		assertEquals(expected, output.toString());
	}

	public void testFailure() {
		String expected= expected(new String[]{".F", "Time: 0", "Failures here", "", "FAILURES!!!", "Tests run: 1,  Failures: 1,  Errors: 0", ""});
		ResultPrinter printer= new TestResultPrinter(new PrintStream(output)) {
			@Override
			public void printFailures(TestResult result) {
				getWriter().println("Failures here");
			}
		};
		runner.setPrinter(printer);
		TestSuite suite = new TestSuite();
		suite.addTest(new TestCase() { @Override
		public void runTest() {throw new AssertionFailedError();}});
		runner.doRun(suite);
		assertEquals(expected, output.toString());
	}
	
	public void testError() {
		String expected= expected(new String[]{".E", "Time: 0", "Errors here", "", "FAILURES!!!", "Tests run: 1,  Failures: 0,  Errors: 1", ""});
		ResultPrinter printer= new TestResultPrinter(new PrintStream(output)) {
			@Override
			public void printErrors(TestResult result) {
				getWriter().println("Errors here");
			}
		};
		runner.setPrinter(printer);
		TestSuite suite = new TestSuite();
		suite.addTest(new TestCase() { @Override
		public void runTest() throws Exception {throw new Exception();}});
		runner.doRun(suite);
		assertEquals(expected, output.toString());
	}
	
	private String expected(String[] lines) {
		OutputStream expected= new ByteArrayOutputStream();
		PrintStream expectedWriter= new PrintStream(expected);
		for (int i= 0; i < lines.length; i++)
			expectedWriter.println(lines[i]);
		return expected.toString(); 
	}

}