具有多个测试的参数化junit测试

Question

参数化测试可以将不同的数据输入到测试中。不过，我创建了一个示例计算器，希望为其创建参数化测试。但是，我发现您只能为单个测试创建一组参数化数据。

我已经创建了参数化测试，用于添加两个数字，得到预期的结果。由于预期结果会有所不同，因此该数据将不适用于减法运算。

有没有可能为每个加、减、乘、除测试提供参数化数据？

非常感谢您的建议，

@RunWith(Parameterized.class)
public class CalculatorModelPresenterTest {

    private CalculatorModel mCalculatorModel;

    /* Array of tests */
    @Parameterized.Parameters
    public static Collection<Object[]> data() {
        return Arrays.asList(new Object[][]{
                {3.0, 4.0, 7.0},
                {4.0, 3.0, 7.0},
                {8.0, 2.0, 10.0},
                {-1.0, 4.0, 3.0},
                {3256.0, 4.0, 3260.0}
        });
    }

    private double mNumberOne;
    private double mNumberTwo;
    private double mExpectedResult;

    /* CONSTRUCTOR THAT ASSIGNS THE FIELDS WITH THE TEST DATA */
    public CalculatorModelPresenterTest(double numberOne, double numberTwo, double expectedResult) {
        mNumberOne = numberOne;
        mNumberTwo = numberTwo;
        mExpectedResult = expectedResult;
    }

    /* THIS TEST WILL PASS AS THE TEST DATA IS FOR ADDING */
    @Test
    public void testAdd() throws Exception {
        final double actualResult = mCalculatorModel.add(mNumberOne, mNumberTwo);
        assertEquals(actualResult, mExpectedResult, 0);
    }

    /* HOWEVER, THIS TEST WILL ALWAYS FAIL AS THE TEST DATA IS CUSTOMIZED FOR THE ADD */
    @Test
    public void testSub() throws Exception {
        final double actualResult = mCalculatorModel.sub(mNumberOne, mNumberTwo);
        assertEquals(actualResult, mExpectedResult, 0);
    }

    @Before
    public void setUp() throws Exception {
        mCalculatorModel = new CalculatorModel();
    }

    @After
    public void tearDown() throws Exception {
        mCalculatorModel = null;
    }
}

Answer 1

只需添加另一个参数如下：

 return Arrays.asList(new Object[][]{
            {3.0, 4.0, 7.0, -1.0},
            {4.0, 3.0, 7.0, 1.0},
            {8.0, 2.0, 10.0, 6.0},
            {-1.0, 4.0, 3.0, -5.0},
            {3256.0, 4.0, 3260.0, 3252.0}
    });

...

private double mExpectedSubResult;

/* CONSTRUCTOR THAT ASSIGNS THE FIELDS WITH THE TEST DATA */
public CalculatorModelPresenterTest(double numberOne, double numberTwo, double expectedResult, double expectedSubResult) {
    mNumberOne = numberOne;
    mNumberTwo = numberTwo;
    mExpectedResult = expectedResult;
    mExpectedSubResult = expectedSubResult;
}
...

/* THIS TEST WILL NOW PASS */
@Test
public void testSub() throws Exception {
    final double actualResult = mCalculatorModel.sub(mNumberOne, mNumberTwo);
    assertEquals(actualResult, mExpectedSubResult, 0);
}

Answer 2

使用JUnit 4，您不能有多个@Parameter方法。您需要为每个带有新参数的操作添加一个新类。

Answer 3

您可以为每个测试编写一个内部类，每个测试都有一组不同的参数，并使用附带的运行程序运行它。

@RunWith(Enclosed.class)
public class CalculatorModelPresenterTest {

    @RunWith(Parameterized.class)
    public static class Sum {

        @Parameterized.Parameters
        public static Object[][] data() {
            return new Object[][]{
                {3.0, 4.0, 7.0},
                {4.0, 3.0, 7.0},
                {8.0, 2.0, 10.0},
                {-1.0, 4.0, 3.0},
                {3256.0, 4.0, 3260.0}
            };
        }

        @Parameterized.Parameter(0)
        private double mNumberOne;
        @Parameterized.Parameter(1)
        private double mNumberTwo;
        @Parameterized.Parameter(2)
        private double mExpectedResult;

        @Test
        public void testAdd() throws Exception {
            CalculatorModel calculatorModel = new CalculatorModel();
            double actualResult = calculatorModel.add(mNumberOne, mNumberTwo);
            assertEquals(actualResult, mExpectedResult, 0);
        }
    }   

    @RunWith(Parameterized.class)
    public static class Difference {

        @Parameterized.Parameters
        public static Object[][] data() {
            return new Object[][]{
                {3.0, 4.0, -1.0},
                {4.0, 3.0, 1.0},
                {8.0, 2.0, 6.0},
                {-1.0, 4.0, -5.0},
                {3256.0, 4.0, 3252.0}
            };
        }

        @Parameterized.Parameter(0)
        private double mNumberOne;
        @Parameterized.Parameter(1)
        private double mNumberTwo;
        @Parameterized.Parameter(2)
        private double mExpectedResult;

        @Test
        public void testSub() throws Exception {
            CalculatorModel calculatorModel = new CalculatorModel();
            double actualResult = calculatorModel.sub(mNumberOne, mNumberTwo);
            assertEquals(actualResult, mExpectedResult, 0);
        }
    } 
}

另一种方法是使用JUnitParams runner。

@RunWith(JUnitParamsRunner.class)
public class CalculatorModelPresenterTest {

    @Test
    @Parameters({
            "3.0, 4.0, 7.0",
            "4.0, 3.0, 7.0",
            "8.0, 2.0, 10.0",
            "-1.0, 4.0, 3.0",
            "3256.0, 4.0, 3260.0" })
    public void testAdd(double first, double second, double expectedResult)
            throws Exception {
        CalculatorModel calculatorModel = new CalculatorModel();
        double actualResult = calculatorModel.add(first, second);
        assertEquals(actualResult, expectedResult, 0);
    }   

    @Test
    @Parameters({
            "3.0, 4.0, -1.0",
            "4.0, 3.0, 1.0",
            "8.0, 2.0, 6.0",
            "-1.0, 4.0, -5.0",
            "3256.0, 4.0, 3252.0" })
    public void testSub(double first, double second, double expectedResult)
            throws Exception {
        CalculatorModel calculatorModel = new CalculatorModel();
        double actualResult = calculatorModel.sub(first, second);
        assertEquals(actualResult, expectedResult, 0);
    } 
}