ParameterizedTestTest.java

package org.junit.tests.running.classes;

import static java.util.Arrays.asList;
import static org.hamcrest.CoreMatchers.allOf;
import static org.hamcrest.CoreMatchers.containsString;
import static org.hamcrest.MatcherAssert.assertThat;
import static org.junit.Assert.assertEquals;
import static org.junit.Assert.assertTrue;
import static org.junit.Assert.fail;
import static org.junit.experimental.results.PrintableResult.testResult;

import java.util.Arrays;
import java.util.Collection;
import java.util.Collections;
import java.util.Iterator;
import java.util.List;
import java.util.concurrent.atomic.AtomicBoolean;

import org.junit.AfterClass;
import org.junit.BeforeClass;
import org.junit.FixMethodOrder;
import org.junit.Test;
import org.junit.runner.Description;
import org.junit.runner.JUnitCore;
import org.junit.runner.Request;
import org.junit.runner.Result;
import org.junit.runner.RunWith;
import org.junit.runner.Runner;
import org.junit.runner.notification.Failure;
import org.junit.runners.MethodSorters;
import org.junit.runners.Parameterized;
import org.junit.runners.Parameterized.Parameter;
import org.junit.runners.Parameterized.Parameters;
import org.junit.runners.Parameterized.UseParametersRunnerFactory;
import org.junit.runners.model.InitializationError;
import org.junit.runners.parameterized.ParametersRunnerFactory;
import org.junit.runners.parameterized.TestWithParameters;

public class ParameterizedTestTest {
    @RunWith(Parameterized.class)
    public static class AdditionTest {
        @Parameters(name = "{index}: {0} + {1} = {2}")
        public static Iterable<Object[]> data() {
            return Arrays.asList(new Object[][] { { 0, 0, 0 }, { 1, 1, 2 },
                    { 3, 2, 5 }, { 4, 3, 7 } });
        }

        private int firstSummand;

        private int secondSummand;

        private int sum;

        public AdditionTest(int firstSummand, int secondSummand, int sum) {
            this.firstSummand = firstSummand;
            this.secondSummand = secondSummand;
            this.sum = sum;
        }

        @Test
        public void test() {
            assertEquals(sum, firstSummand + secondSummand);
        }
    }

    @Test
    public void countsRuns() {
        Result result = JUnitCore.runClasses(AdditionTest.class);
        assertEquals(4, result.getRunCount());
    }

    @Test
    public void countBeforeRun() throws Exception {
        Runner runner = Request.aClass(AdditionTest.class).getRunner();
        assertEquals(4, runner.testCount());
    }

    @Test
    public void plansNamedCorrectly() throws Exception {
        Runner runner = Request.aClass(AdditionTest.class).getRunner();
        Description description = runner.getDescription();
        assertEquals("[2: 3 + 2 = 5]", description.getChildren().get(2)
                .getDisplayName());
    }

    @RunWith(Parameterized.class)
    public static class ThreeFailures {
        @Parameters(name = "{index}: x={0}")
        public static Collection<Integer> data() {
            return Arrays.asList(1, 2, 3);
        }

        @Parameter(0)
        public int unused;

        @Test
        public void testSomething() {
            fail();
        }
    }

    @Test
    public void countsFailures() throws Exception {
        Result result = JUnitCore.runClasses(ThreeFailures.class);
        assertEquals(3, result.getFailureCount());
    }

    @Test
    public void failuresNamedCorrectly() {
        Result result = JUnitCore.runClasses(ThreeFailures.class);
        assertEquals(
                "testSomething[0: x=1](" + ThreeFailures.class.getName() + ")",
                result.getFailures().get(0).getTestHeader());
    }

    @RunWith(Parameterized.class)
    public static class ParameterizedWithoutSpecialTestname {
        @Parameters
        public static Collection<Object[]> data() {
            return Arrays.asList(new Object[][]{{3}, {3}});
        }

        public ParameterizedWithoutSpecialTestname(Object something) {
        }

        @Test
        public void testSomething() {
        }
    }

    @Test
    public void usesIndexAsTestName() {
        Runner runner = Request
                .aClass(ParameterizedWithoutSpecialTestname.class).getRunner();
        Description description = runner.getDescription();
        assertEquals("[1]", description.getChildren().get(1).getDisplayName());
    }

    @RunWith(Parameterized.class)
    public static class AdditionTestWithAnnotatedFields {
        @Parameters(name = "{index}: {0} + {1} = {2}")
        public static Iterable<Object[]> data() {
            return Arrays.asList(new Object[][] { { 0, 0, 0 }, { 1, 1, 2 },
                    { 3, 2, 5 }, { 4, 3, 7 } });
        }

        @Parameter(0)
        public int firstSummand;

        @Parameter(1)
        public int secondSummand;

        @Parameter(2)
        public int sum;

        @Test
        public void test() {
            assertEquals(sum, firstSummand + secondSummand);
        }
    }

    @Test
    public void providesDataByAnnotatedFields() {
        Result result = JUnitCore.runClasses(AdditionTestWithAnnotatedFields.class);
        assertEquals(4, result.getRunCount());
        assertEquals(0, result.getFailureCount());
    }

    @RunWith(Parameterized.class)
    static public class BadIndexForAnnotatedFieldTest {
        @Parameters
        public static Collection<Object[]> data() {
            return Arrays.asList(new Object[][]{{0}});
        }

        @Parameter(2)
        public int fInput;

        public int fExpected;

        @Test
        public void test() {
            assertEquals(fExpected, fib(fInput));
        }

        private int fib(int x) {
            return 0;
        }
    }

    @Test
    public void failureOnInitialization() {
        Result result = JUnitCore.runClasses(BadIndexForAnnotatedFieldTest.class);
        assertEquals(1, result.getFailureCount());
        List<Failure> failures = result.getFailures();
        assertThat(failures.get(0).getException().getMessage(), allOf(
                containsString("Invalid @Parameter value: 2. @Parameter fields counted: 1. Please use an index between 0 and 0."),
                containsString("@Parameter(0) is never used.")));
    }

    @RunWith(Parameterized.class)
    static public class BadNumberOfAnnotatedFieldTest {
        @Parameters
        public static Collection<Object[]> data() {
            return Arrays.asList(new Object[][]{{0, 0}});
        }

        @Parameter(0)
        public int fInput;

        public int fExpected;

        @Test
        public void test() {
            assertEquals(fExpected, fib(fInput));
        }

        private int fib(int x) {
            return 0;
        }
    }

    @Test
    public void numberOfFieldsAndParametersShouldMatch() {
        Result result = JUnitCore.runClasses(BadNumberOfAnnotatedFieldTest.class);
        assertEquals(1, result.getFailureCount());
        List<Failure> failures = result.getFailures();
        assertTrue(failures.get(0).getException().getMessage().contains("Wrong number of parameters and @Parameter fields. @Parameter fields counted: 1, available parameters: 2."));
    }

    private static String fLog;

    @RunWith(Parameterized.class)
    static public class BeforeAndAfter {
        @BeforeClass
        public static void before() {
            fLog += "before ";
        }

        @AfterClass
        public static void after() {
            fLog += "after ";
        }

        public BeforeAndAfter(int x) {

        }

        @Parameters
        public static Collection<Object[]> data() {
            return Arrays.asList(new Object[][]{{3}});
        }

        @Test
        public void aTest() {
        }
    }

    @Test
    public void beforeAndAfterClassAreRun() {
        fLog = "";
        JUnitCore.runClasses(BeforeAndAfter.class);
        assertEquals("before after ", fLog);
    }

    @RunWith(Parameterized.class)
    @FixMethodOrder(MethodSorters.NAME_ASCENDING)
    public static class BeforeParamAndAfterParam {
        @BeforeClass
        public static void before() {
            fLog += "beforeClass ";
        }

        @Parameterized.BeforeParam
        public static void beforeParam(String x) {
            fLog += "before(" + x + ") ";
        }

        @Parameterized.AfterParam
        public static void afterParam() {
            fLog += "afterParam ";
        }

        @AfterClass
        public static void after() {
            fLog += "afterClass ";
        }

        private final String x;

        public BeforeParamAndAfterParam(String x) {
            this.x = x;
        }

        @Parameters
        public static Collection<String> data() {
            return Arrays.asList("A", "B");
        }

        @Test
        public void first() {
            fLog += "first(" + x + ") ";
        }

        @Test
        public void second() {
            fLog += "second(" + x + ") ";
        }
    }

    @Test
    public void beforeParamAndAfterParamAreRun() {
        fLog = "";
        Result result = JUnitCore.runClasses(BeforeParamAndAfterParam.class);
        assertEquals(0, result.getFailureCount());
        assertEquals("beforeClass before(A) first(A) second(A) afterParam "
                + "before(B) first(B) second(B) afterParam afterClass ", fLog);
    }

    @RunWith(Parameterized.class)
    @FixMethodOrder(MethodSorters.NAME_ASCENDING)
    public static class MultipleBeforeParamAndAfterParam {
        @Parameterized.BeforeParam
        public static void before1() {
            fLog += "before1() ";
        }

        @Parameterized.BeforeParam
        public static void before2(String x) {
            fLog += "before2(" + x + ") ";
        }

        @Parameterized.AfterParam
        public static void after2() {
            fLog += "after2() ";
        }

        @Parameterized.AfterParam
        public static void after1(String x) {
            fLog += "after1(" + x + ") ";
        }

        private final String x;

        public MultipleBeforeParamAndAfterParam(String x) {
            this.x = x;
        }

        @Parameters
        public static Collection<String> data() {
            return Arrays.asList("A", "B");
        }

        @Test
        public void first() {
            fLog += "first(" + x + ") ";
        }

        @Test
        public void second() {
            fLog += "second(" + x + ") ";
        }
    }

    @Test
    public void multipleBeforeParamAndAfterParamAreRun() {
        fLog = "";
        Result result = JUnitCore.runClasses(MultipleBeforeParamAndAfterParam.class);
        assertEquals(0, result.getFailureCount());
        assertEquals("before1() before2(A) first(A) second(A) after1(A) after2() "
                + "before1() before2(B) first(B) second(B) after1(B) after2() ", fLog);
    }

    @RunWith(Parameterized.class)
    @FixMethodOrder(MethodSorters.NAME_ASCENDING)
    public static class MultipleParametersBeforeParamAndAfterParam {
        @Parameterized.BeforeParam
        public static void before(String x, int y) {
            fLog += "before(" + x + "," + y + ") ";
        }

        @Parameterized.AfterParam
        public static void after(String x, int y) {
            fLog += "after(" + x + "," + y + ") ";
        }

        private final String x;
        private final int y;

        public MultipleParametersBeforeParamAndAfterParam(String x, int y) {
            this.x = x;
            this.y = y;
        }

        @Parameters
        public static Collection<Object[]> data() {
            return Arrays.asList(new Object[]{"A", 1}, new Object[]{"B", 2});
        }

        @Test
        public void first() {
            fLog += "first(" + x + "," + y + ") ";
        }

        @Test
        public void second() {
            fLog += "second(" + x + "," + y + ") ";
        }
    }

    @Test
    public void multipleParametersBeforeParamAndAfterParamAreRun() {
        fLog = "";
        Result result = JUnitCore.runClasses(MultipleParametersBeforeParamAndAfterParam.class);
        assertEquals(0, result.getFailureCount());
        assertEquals("before(A,1) first(A,1) second(A,1) after(A,1) "
                + "before(B,2) first(B,2) second(B,2) after(B,2) ", fLog);
    }

    @RunWith(Parameterized.class)
    public static class BeforeParamAndAfterParamError {
        @Parameterized.BeforeParam
        public void beforeParam(String x) {
        }

        @Parameterized.AfterParam
        private static void afterParam() {
        }

        public BeforeParamAndAfterParamError(String x) {
        }

        @Parameters
        public static Collection<String> data() {
            return Arrays.asList("A", "B");
        }

        @Test
        public void test() {
        }
    }

    @Test
    public void beforeParamAndAfterParamValidation() {
        fLog = "";
        Result result = JUnitCore.runClasses(BeforeParamAndAfterParamError.class);
        assertEquals(1, result.getFailureCount());
        List<Failure> failures = result.getFailures();
        assertThat(failures.get(0).getMessage(), containsString("beforeParam() should be static"));
        assertThat(failures.get(0).getMessage(), containsString("afterParam() should be public"));
    }

    @RunWith(Parameterized.class)
    public static class BeforeParamAndAfterParamErrorNumberOfParameters {
        @Parameterized.BeforeParam
        public static void beforeParam(String x, String y) {
        }

        @Parameterized.AfterParam
        public static void afterParam(String x, String y, String z) {
        }

        public BeforeParamAndAfterParamErrorNumberOfParameters(String x) {
        }

        @Parameters
        public static Collection<String> data() {
            return Arrays.asList("A", "B", "C", "D");
        }

        @Test
        public void test() {
        }
    }

    @Test
    public void beforeParamAndAfterParamValidationNumberOfParameters() {
        fLog = "";
        Result result = JUnitCore.runClasses(BeforeParamAndAfterParamErrorNumberOfParameters.class);
        assertEquals(1, result.getFailureCount());
        List<Failure> failures = result.getFailures();
        assertThat(failures.get(0).getMessage(),
                containsString("Method beforeParam() should have 0 or 1 parameter(s)"));
        assertThat(failures.get(0).getMessage(),
                containsString("Method afterParam() should have 0 or 1 parameter(s)"));
    }

    @RunWith(Parameterized.class)
    static public class EmptyTest {
        @BeforeClass
        public static void before() {
            fLog += "before ";
        }

        @AfterClass
        public static void after() {
            fLog += "after ";
        }
    }

    @Test
    public void validateClassCatchesNoParameters() {
        Result result = JUnitCore.runClasses(EmptyTest.class);
        assertEquals(1, result.getFailureCount());
    }

    @RunWith(Parameterized.class)
    static public class IncorrectTest {
        @Test
        public int test() {
            return 0;
        }

        @Parameters
        public static Collection<Object[]> data() {
            return Collections.singletonList(new Object[]{1});
        }
    }

    @Test
    public void failuresAddedForBadTestMethod() throws Exception {
        Result result = JUnitCore.runClasses(IncorrectTest.class);
        assertEquals(1, result.getFailureCount());
    }

    @RunWith(Parameterized.class)
    static public class ProtectedParametersTest {
        @Parameters
        protected static Collection<Object[]> data() {
            return Collections.emptyList();
        }

        @Test
        public void aTest() {
        }
    }

    @Test
    public void meaningfulFailureWhenParametersNotPublic() {
        assertTestCreatesSingleFailureWithMessage(ProtectedParametersTest.class,
                "No public static parameters method on class "
                        + ProtectedParametersTest.class.getName());
    }

    @RunWith(Parameterized.class)
    static public class ParametersNotIterable {
        @Parameters
        public static String data() {
            return "foo";
        }

        @Test
        public void aTest() {
        }
    }

    @Test
    public void meaningfulFailureWhenParametersAreNotAnIterable() {
        assertThat(
                testResult(ParametersNotIterable.class).toString(),
                containsString("ParametersNotIterable.data() must return an Iterable of arrays."));
    }

    @RunWith(Parameterized.class)
    static public class PrivateConstructor {
        private PrivateConstructor(int x) {

        }

        @Parameters
        public static Collection<Object[]> data() {
            return Arrays.asList(new Object[][]{{3}});
        }

        @Test
        public void aTest() {
        }
    }

    @Test(expected = InitializationError.class)
    public void exceptionWhenPrivateConstructor() throws Throwable {
        new Parameterized(PrivateConstructor.class);
    }

    @RunWith(Parameterized.class)
    public static class AdditionTestWithArray {
        @Parameters(name = "{index}: {0} + {1} = {2}")
        public static Object[][] data() {
            return new Object[][] { { 0, 0, 0 }, { 1, 1, 2 }, { 3, 2, 5 },
                    { 4, 3, 7 } };
        }

        @Parameter(0)
        public int firstSummand;

        @Parameter(1)
        public int secondSummand;

        @Parameter(2)
        public int sum;

        @Test
        public void test() {
            assertEquals(sum, firstSummand + secondSummand);
        }
    }

    @Test
    public void runsEveryTestOfArray() {
        Result result= JUnitCore.runClasses(AdditionTestWithArray.class);
        assertEquals(4, result.getRunCount());
    }

    @RunWith(Parameterized.class)
    static public class SingleArgumentTestWithArray {
        @Parameters
        public static Object[] data() {
            return new Object[] { "first test", "second test" };
        }

        public SingleArgumentTestWithArray(Object argument) {
        }

        @Test
        public void aTest() {
        }
    }

    @Test
    public void runsForEverySingleArgumentOfArray() {
        Result result= JUnitCore.runClasses(SingleArgumentTestWithArray.class);
        assertEquals(2, result.getRunCount());
    }

    @RunWith(Parameterized.class)
    static public class SingleArgumentTestWithIterable {
        private static final AtomicBoolean dataCalled = new AtomicBoolean(false);

        @Parameters
        public static Iterable<? extends Object> data() {
            if (!dataCalled.compareAndSet(false, true)) {
                fail("Should not call @Parameters method more than once");
            }
            return new OneShotIterable<String>(asList("first test", "second test"));
        }

        public SingleArgumentTestWithIterable(Object argument) {
        }

        @Test
        public void aTest() {
        }
  	}

    private static class OneShotIterable<T> implements Iterable<T> {
        private final Iterable<T> delegate;
        private final AtomicBoolean iterated = new AtomicBoolean(false);

        OneShotIterable(Iterable<T> delegate) {
            this.delegate = delegate;
        }

        public Iterator<T> iterator() {
            if (iterated.compareAndSet(false, true)) {
                return delegate.iterator();
            }
            throw new IllegalStateException("Cannot call iterator() more than once");
        }
    }

    @Test
    public void runsForEverySingleArgumentOfIterable() {
        Result result= JUnitCore
                .runClasses(SingleArgumentTestWithIterable.class);
        assertEquals(2, result.getRunCount());
    }

    @RunWith(Parameterized.class)
    static public class SingleArgumentTestWithCollection {
        @Parameters
        public static Iterable<? extends Object> data() {
            return Collections.unmodifiableCollection(asList("first test", "second test"));
        }

        public SingleArgumentTestWithCollection(Object argument) {
        }

        @Test
        public void aTest() {
        }
    }

    @Test
    public void runsForEverySingleArgumentOfCollection() {
        Result result= JUnitCore
                .runClasses(SingleArgumentTestWithCollection.class);
        assertEquals(2, result.getRunCount());
    }


    static public class ExceptionThrowingRunnerFactory implements
            ParametersRunnerFactory {
        public Runner createRunnerForTestWithParameters(TestWithParameters test)
                throws InitializationError {
            throw new InitializationError(
                    "Called ExceptionThrowingRunnerFactory.");
        }
    }

    @RunWith(Parameterized.class)
    @UseParametersRunnerFactory(ExceptionThrowingRunnerFactory.class)
    static public class TestWithUseParametersRunnerFactoryAnnotation {
        @Parameters
        public static Iterable<? extends Object> data() {
            return asList("single test");
        }

        public TestWithUseParametersRunnerFactoryAnnotation(Object argument) {
        }

        @Test
        public void aTest() {
        }
    }

    @Test
    public void usesParametersRunnerFactoryThatWasSpecifiedByAnnotation() {
        assertTestCreatesSingleFailureWithMessage(
                TestWithUseParametersRunnerFactoryAnnotation.class,
                "Called ExceptionThrowingRunnerFactory.");
    }

    private void assertTestCreatesSingleFailureWithMessage(Class<?> test, String message) {
        Result result = JUnitCore.runClasses(test);
        assertEquals(1, result.getFailures().size());
        assertEquals(message, result.getFailures().get(0).getMessage());
    }
    
    @RunWith(Parameterized.class)
    @UseParametersRunnerFactory(ExceptionThrowingRunnerFactory.class)
    public static abstract class UseParameterizedFactoryAbstractTest {
        @Parameters
        public static Iterable<? extends Object> data() {
            return asList("single test");
        }
    }
    
    public static class UseParameterizedFactoryTest extends
            UseParameterizedFactoryAbstractTest {

        public UseParameterizedFactoryTest(String parameter) {

        }

        @Test
        public void parameterizedTest() {
        }
    }
    
    @Test
    public void usesParametersRunnerFactoryThatWasSpecifiedByAnnotationInSuperClass() {
        assertTestCreatesSingleFailureWithMessage(
                UseParameterizedFactoryTest.class,
                "Called ExceptionThrowingRunnerFactory.");
    }
}