user/test/com/google/gwt/junit/TestSuiteWithOrder.java

/*
 * Copyright 2012 Google Inc.
 *
 * Licensed under the Apache License, Version 2.0 (the "License"); you may not
 * use this file except in compliance with the License. You may obtain a copy of
 * the License at
 *
 * http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
 * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
 * License for the specific language governing permissions and limitations under
 * the License.
 */
package com.google.gwt.junit;

import junit.framework.Test;
import junit.framework.TestCase;
import junit.framework.TestSuite;

import java.lang.reflect.Method;
import java.lang.reflect.Modifier;
import java.util.Arrays;
import java.util.Comparator;

/**
 * Add {@link TestSuite} that runs test cases in alphabetical order.
 */
class TestSuiteWithOrder extends TestSuite {

  /*
   * Implementation Note: When batching is active, TestModuleInfo in GWTTestCase#ALL_GWT_TESTS
   * accidentally forces the test execution order that is derived from first time the TestCase is
   * instantiated. The implementation of this class should guarantee the order not only by sorting
   * TestCases but also creating them in order.
   */

  public TestSuiteWithOrder(Class<? extends TestCase> clazz) {
    for (Class<?> c = clazz; Test.class.isAssignableFrom(c); c = c.getSuperclass()) {
      for (Method each : getDeclaredMethods(c)) {
        if (isTestMethod(each)) {
          addTestMethod(each, clazz);
        }
      }
    }
    if (countTestCases() == 0) {
      addTest(warning("No tests found in " + clazz.getName()));
    }
  }

  private void addTestMethod(Method m, Class<?> theClass) {
    if (!Modifier.isPublic(m.getModifiers())) {
      addTest(warning("Test method isn't public: " + m.getName() + "(" + theClass.getName() + ")"));
      return;
    }
    addTest(createTest(theClass, m.getName()));
  }

  private boolean isTestMethod(Method m) {
    return m.getParameterTypes().length == 0
        && m.getName().startsWith("test")
        && m.getReturnType().equals(Void.TYPE);
  }

  private Method[] getDeclaredMethods(Class<?> clazz) {
    Method[] methods = clazz.getDeclaredMethods();
    Arrays.sort(methods, new Comparator<Method>() {
      @Override
      public int compare(Method m1, Method m2) {
        return m1.toString().compareTo(m2.toString());
      }
    });
    return methods;
  }
}