Support the selection of a default Runner in ClassRequest

src/main/java/org/junit/internal/builders/AllDefaultPossibilitiesBuilder.java

@@ -31,6 +31,7 @@ public Runner runnerForClass(Class<?> testClass) throws Throwable {
                 annotatedBuilder(),
                 suiteMethodBuilder(),
                 junit3Builder(),
+                defaultBuilder(),
                 junit4Builder());
 
         for (RunnerBuilder each : builders) {
@@ -58,6 +59,10 @@ protected IgnoredBuilder ignoredBuilder() {
         return new IgnoredBuilder();
     }
 
+    protected RunnerBuilder defaultBuilder() {
+        return new NullBuilder();
+    }
+
     protected RunnerBuilder suiteMethodBuilder() {
         if (canUseSuiteMethod) {
             return new SuiteMethodBuilder();

src/main/java/org/junit/internal/builders/AnnotatedBuilder.java

@@ -2,7 +2,6 @@
 
 import org.junit.runner.RunWith;
 import org.junit.runner.Runner;
-import org.junit.runners.model.InitializationError;
 import org.junit.runners.model.RunnerBuilder;
 
 import java.lang.reflect.Modifier;
@@ -69,8 +68,6 @@
  * @since 4.0
  */
 public class AnnotatedBuilder extends RunnerBuilder {
-    private static final String CONSTRUCTOR_ERROR_FORMAT = "Custom runner class %s should have a public constructor with signature %s(Class testClass)";
-
     private final RunnerBuilder suiteBuilder;
 
     public AnnotatedBuilder(RunnerBuilder suiteBuilder) {
@@ -83,7 +80,7 @@ public Runner runnerForClass(Class<?> testClass) throws Exception {
              currentTestClass = getEnclosingClassForNonStaticMemberClass(currentTestClass)) {
             RunWith annotation = currentTestClass.getAnnotation(RunWith.class);
             if (annotation != null) {
-                return buildRunner(annotation.value(), testClass);
+                return buildRunner(annotation.value(), testClass, suiteBuilder);
             }
         }
 
@@ -97,20 +94,4 @@ private Class<?> getEnclosingClassForNonStaticMemberClass(Class<?> currentTestCl
             return null;
         }
     }
-
-    public Runner buildRunner(Class<? extends Runner> runnerClass,
-            Class<?> testClass) throws Exception {
-        try {
-            return runnerClass.getConstructor(Class.class).newInstance(testClass);
-        } catch (NoSuchMethodException e) {
-            try {
-                return runnerClass.getConstructor(Class.class,
-                        RunnerBuilder.class).newInstance(testClass, suiteBuilder);
-            } catch (NoSuchMethodException e2) {
-                String simpleName = runnerClass.getSimpleName();
-                throw new InitializationError(String.format(
-                        CONSTRUCTOR_ERROR_FORMAT, simpleName, simpleName));
-            }
-        }
-    }
 }

src/main/java/org/junit/internal/builders/DefaultBuilder.java

@@ -0,0 +1,18 @@
+package org.junit.internal.builders;
+
+import org.junit.runner.Runner;
+import org.junit.runners.model.RunnerBuilder;
+
+public class DefaultBuilder extends RunnerBuilder {
+  private Class<? extends Runner> defaultRunnerClass;
+  private RunnerBuilder suiteBuilder;
+
+  public DefaultBuilder(Class<? extends Runner> defaultRunnerClass, RunnerBuilder suiteBuilder) {
+    this.defaultRunnerClass = defaultRunnerClass;
+    this.suiteBuilder = suiteBuilder;
+  }
+
+  public Runner runnerForClass(Class<?> testClass) throws Throwable {
+        return buildRunner(defaultRunnerClass, testClass, suiteBuilder);
+    }
+}

src/main/java/org/junit/internal/requests/ClassRequest.java

@@ -1,6 +1,7 @@
 package org.junit.internal.requests;
 
 import org.junit.internal.builders.AllDefaultPossibilitiesBuilder;
+import org.junit.internal.builders.DefaultBuilder;
 import org.junit.internal.builders.SuiteMethodBuilder;
 import org.junit.runner.Request;
 import org.junit.runner.Runner;
@@ -17,10 +18,17 @@ public class ClassRequest extends Request {
     private final Class<?> fTestClass;
     private final boolean canUseSuiteMethod;
     private volatile Runner runner;
+    private Class<? extends Runner> defaultRunnerClass;
 
-    public ClassRequest(Class<?> testClass, boolean canUseSuiteMethod) {
+    public ClassRequest(Class<?> testClass, boolean canUseSuiteMethod,
+                        Class<? extends Runner> defaultRunnerClass) {
         this.fTestClass = testClass;
         this.canUseSuiteMethod = canUseSuiteMethod;
+        this.defaultRunnerClass = defaultRunnerClass;
+    }
+
+    public ClassRequest(Class<?> testClass, boolean canUseSuiteMethod) {
+        this(testClass, canUseSuiteMethod, null);
     }
 
     public ClassRequest(Class<?> testClass) {
@@ -45,6 +53,14 @@ private class CustomAllDefaultPossibilitiesBuilder extends AllDefaultPossibiliti
         protected RunnerBuilder suiteMethodBuilder() {
             return new CustomSuiteMethodBuilder();
         }
+
+        @Override
+        protected RunnerBuilder defaultBuilder() {
+            if (defaultRunnerClass != null) {
+                return new DefaultBuilder(defaultRunnerClass, this);
+            }
+            return super.defaultBuilder();
+        }
     }
 
     /*

src/main/java/org/junit/runner/Request.java

@@ -61,6 +61,19 @@ public static Request classWithoutSuiteMethod(Class<?> clazz) {
         return new ClassRequest(clazz, false);
     }
 
+    /**
+     * Create a <code>Request</code> that, when processed, will run all the tests
+     * in a class. If the class does not set the runner to use, a runner of the given
+     * class will be used by default.
+     *
+     * @param clazz the class containing the tests
+     * @param defaultRunnerClass the class of the runner to use by default
+     * @return a <code>Request</code> that will cause all tests in the class to be run
+     */
+    public static Request classWithDefaultRunner(Class<?> clazz, Class<? extends Runner> defaultRunnerClass) {
+        return new ClassRequest(clazz, true, defaultRunnerClass);
+    }
+
     /**
      * Create a <code>Request</code> that, when processed, will run all the tests
      * in a set of classes.

src/main/java/org/junit/runners/model/RunnerBuilder.java

@@ -37,6 +37,8 @@
  * @since 4.5
  */
 public abstract class RunnerBuilder {
+    private static final String CONSTRUCTOR_ERROR_FORMAT = "Custom runner class %s should have a public constructor with signature %s(Class testClass)";
+
     private final Set<Class<?>> parents = new HashSet<Class<?>>();
 
     /**
@@ -80,6 +82,22 @@ void removeParent(Class<?> klass) {
         parents.remove(klass);
     }
 
+    public Runner buildRunner(Class<? extends Runner> runnerClass,
+            Class<?> testClass, RunnerBuilder suiteBuilder) throws Exception {
+        try {
+            return runnerClass.getConstructor(Class.class).newInstance(testClass);
+        } catch (NoSuchMethodException e) {
+            try {
+                return runnerClass.getConstructor(Class.class,
+                        RunnerBuilder.class).newInstance(testClass, suiteBuilder);
+            } catch (NoSuchMethodException e2) {
+                String simpleName = runnerClass.getSimpleName();
+                throw new InitializationError(String.format(
+                        CONSTRUCTOR_ERROR_FORMAT, simpleName, simpleName));
+            }
+        }
+    }
+
     /**
      * Constructs and returns a list of Runners, one for each child class in
      * {@code children}.  Care is taken to avoid infinite recursion: