FastTestsOnlySuite.java

package com.amazonaws.encryptionsdk;

import java.util.concurrent.TimeUnit;

import org.junit.ClassRule;
import org.junit.experimental.categories.Categories;
import org.junit.rules.TestRule;
import org.junit.rules.Timeout;
import org.junit.runner.Description;
import org.junit.runner.RunWith;
import org.junit.runner.Runner;
import org.junit.runners.Suite;
import org.junit.runners.model.InitializationError;
import org.junit.runners.model.RunnerBuilder;
import org.junit.runners.model.Statement;

/**
 * This test suite is intended to assist in rapid development; it filters out some of the slower, more exhaustive tests
 * in the overall test suite to allow for a rapid edit-test cycle.
 */
@RunWith(FastTestsOnlySuite.CustomRunner.class)
@Suite.SuiteClasses({
        AllTestsSuite.class
})
@Categories.ExcludeCategory(SlowTestCategory.class)
public class FastTestsOnlySuite {
    private static InheritableThreadLocal<Boolean> IS_FAST_TEST_SUITE_ACTIVE = new InheritableThreadLocal<Boolean>() {
        @Override protected Boolean initialValue() {
            return false;
        }
    };

    // This method is used to adjust DataProviders to provide a smaller subset of their test cases when the fast tests
    // are selected
    public static boolean isFastTestSuiteActive() {
        return IS_FAST_TEST_SUITE_ACTIVE.get();
    }

    // Require that this fast suite completes relatively quickly. If you're seeing this timeout get hit, it's time to
    // pare down tests some more. As a general rule of thumb, we should avoid any single test taking more than 10s, and
    // try to keep the number of such slow tests to a minimum.
    @ClassRule
    public static Timeout timeout = new Timeout(2, TimeUnit.MINUTES);

    @ClassRule
    public static EnableFastSuite enableFastSuite = new EnableFastSuite();

    // TestRules run over the execution of tests, but not over the generation of parameterized test data...
    private static class EnableFastSuite implements TestRule {
        @Override public Statement apply(
                Statement base, Description description
        ) {
            return new Statement() {
                @Override public void evaluate() throws Throwable {
                    Boolean oldValue = IS_FAST_TEST_SUITE_ACTIVE.get();

                    try {
                        IS_FAST_TEST_SUITE_ACTIVE.set(true);
                        base.evaluate();
                    } finally {
                        IS_FAST_TEST_SUITE_ACTIVE.set(oldValue);
                    }
                }
            };
        }
    }

    // ... so we also need a custom TestRunner that will pass the flag on to the parameterized test data generators.
    public static class CustomRunner extends Categories {
        public CustomRunner(Class<?> klass, RunnerBuilder builder) throws InitializationError {
            super(
                    klass,
                    new RunnerBuilder() {
                        @Override public Runner runnerForClass(Class<?> testClass) throws Throwable {
                            Boolean oldValue = IS_FAST_TEST_SUITE_ACTIVE.get();

                            try {
                                IS_FAST_TEST_SUITE_ACTIVE.set(true);
                                Runner r = builder.runnerForClass(testClass);
                                return r;
                            } finally {
                                IS_FAST_TEST_SUITE_ACTIVE.set(oldValue);
                            }
                        }
                    }
            );
        }
    }
}