Test Utilities

Collecting some helpful testing-related utilities.

Gradle Usage

repositories {
    mavenCentral()
}

dependencies {
    classpath 'com.trigonic:test-utils:0.6'
}

JUnit Test Suite Discovery

In addition to JUnit's built-in @SuiteClasses annotation, the Suite extension provided by this project allows you to specify @SuiteBaseClass to allow runtime scanning for components to the test suite:

import com.trigonic.utils.test.junit.SuiteBaseClass;

@RunWith(Suite.class)
@SuiteBaseClass(MyTestBase.class)
public class SomeSuite {
    ...
}

This will search for subclasses of the specified base class to include in the suite, by default looking under the same package as that base class.

Enhanced JUnit Test Parameterization

JUnit's built-in test parameterization, accessed through the Parameterized runner, is helpful but doesn't produce very usable JUnit test labels for integrated development environments (IDEs) and can be overly verbose for simple single-value parameterization. The Parameterized class in this package extends JUnit's and attempts to provide an improved experience.

Using this on a class requires an annotation on the class, an annotated static method that returns the parameters to use, and a constructor that matches the parameters:

import com.trigonic.utils.test.junit.Parameterized;
import com.trigonic.utils.test.junit.Parameters;

@RunWith(Parameterized.class)
public class SomeTest {
    ...
    @Parameters
    public static Object[][] parameterMethod() {
        return /* an array of arrays */;
    }
    ...
    public SomeTest( /* parameters that match the array returned above */ ) {{
        ...
    }
    ...
}

If the constructor only takes a single value, then the @Parameters method can return a one-dimensional array. This method can also return an array, Iterable, or Collection.

To aid in the presentation of the resulting tests, you can control the labels applied to the test through a LabelMaker. This can be specified through a static, annotated factory method:

import com.trigonic.utils.test.junit.Parameterized;
import com.trigonic.utils.test.junit.Parameters;
import com.trigonic.utils.test.junit.LabelMakerFactory;

@RunWith(Parameterized.class)
public class SomeTest {
    ...
    @LabelMakerFactory
    public static LabelMaker labelMaker() {
        return /* an instance of LabelMaker */
    }
    ...
}

You can also just specify the LabelMaker class to use, if it doesn't require any special construction:

import com.trigonic.utils.test.junit.Parameterized;
import com.trigonic.utils.test.junit.Parameters;
import com.trigonic.utils.test.junit.LabelMakerClass;

@RunWith(Parameterized.class)
@LabelMakerClass(DefaultLabelMaker.class)
public class SomeTest {
    ...
}

Delayed Evaluation of Asserts

Rather than sleeping a fixed (maximum amount) and then asserting a condition, it's often more efficient to poll that condition and timeout after that maximum amount of time has elapsed:

import com.trigonic.utils.test.junit.DelayedAssert;
....
DelayedAssert.assertEqualsAfter(expected, timeout, [pollInterval,] new Callable() { ... });

Also available are assertNotEqualsAfter, assertTrueAfter, assertFalseAfter, assertSameAfter, assertDifferentAfter, assertNullAfter, and assertNotNullAfter.

This is even easier in Groovy in that you can directly use a closure:

import static com.trigonic.utils.test.junit.DelayedAssert.*
....
assertEqualsAfter(expected, timeout) { valueToTest }