Surefire is not picking up Junit 4 tests

For some reason I cannot get Maven 2 Surefire plugin to execute JUnit 4 test class.

public class SimpleTest {
  @org.junit.Test
  public void simple() {
     System.out.println("foo");
  }
}

However if I change this class to be JUnit-3 like, such as

public class SimpleTest extends junit.framework.TestCase {
  public void testBar() {
     System.out.println("bar");
  }

  @org.junit.Test
  public void simple() {
     System.out.println("foo");
  }
}

then it gets executed. Here's what I've done:

verified Maven version: Apache Maven 2.2.1 (r801777; 2009-08-06 20:16:01+0100)
verified Surefire version: followed this advice
verified Surefire version: checked Surefire jars in my ~/.m2/repository/org/apache/maven/surefire -- all of them are either version 2.4.2 or 2.4.3
done a mvn dependency:tree | grep junit to ensure I only depend on junit version 4.7

The module I am having this problem at doesn't have JUnit 3 tests.

Is there anything else I am missing?

Solution

mvn -X helped me to reveal the following:

...
[INFO] [surefire:test {execution: default-test}]
[DEBUG] dummy:dummy:jar:1.0 (selected for null)
[DEBUG]   org.apache.maven.surefire:surefire-booter:jar:2.4.3:runtime (selected for runtime)
[DEBUG]     org.apache.maven.surefire:surefire-api:jar:2.4.3:runtime (selected for runtime)
[DEBUG] Adding to surefire booter test classpath: /home/mindas/.m2/repository/org/apache/maven/surefire/surefire-booter/2.4.3/surefire-booter-2.4.3.jar
[DEBUG] Adding to surefire booter test classpath: /home/mindas/.m2/repository/org/apache/maven/surefire/surefire-api/2.4.3/surefire-api-2.4.3.jar
[DEBUG] dummy:dummy:jar:1.0 (selected for null)
[DEBUG]   org.testng:testng:jar:jdk15:5.8:test (selected for test)
[DEBUG]     junit:junit:jar:3.8.1:test (selected for test)
[DEBUG] Adding to surefire booter test classpath: /home/mindas/.m2/repository/org/testng/testng/5.8/testng-5.8-jdk15.jar
[DEBUG] Adding to surefire booter test classpath: /home/mindas/.m2/repository/junit/junit/3.8.1/junit-3.8.1.jar
[DEBUG] dummy:dummy:jar:1.0 (selected for null)
[DEBUG] Retrieving parent-POM: org.apache.maven.surefire:surefire-providers:pom:2.4.3 for project: null:surefire-testng:jar:null from the repository.
[DEBUG] Adding managed dependencies for unknown:surefire-testng
[DEBUG]   org.apache.maven.surefire:surefire-api:jar:2.4.3
[DEBUG]   org.apache.maven.surefire:surefire-booter:jar:2.4.3
[DEBUG]   org.codehaus.plexus:plexus-utils:jar:1.5.1
[DEBUG]   org.apache.maven.surefire:surefire-testng:jar:2.4.3:test (selected for test)
[DEBUG]     org.apache.maven:maven-artifact:jar:2.0:test (selected for test)
[DEBUG]       org.codehaus.plexus:plexus-utils:jar:1.0.4:test (selected for test)
[DEBUG]     junit:junit:jar:3.8.1:test (selected for test)
[DEBUG]     org.testng:testng:jar:jdk15:5.7:test (selected for test)
[DEBUG]     org.apache.maven.surefire:surefire-api:jar:2.4.3:test (selected for test)
...
[DEBUG] Test Classpath :
...
[DEBUG]   /home/mindas/.m2/repository/junit/junit/4.7/junit-4.7.jar

So it seems that the problem was coming from testng jar requiring JUnit v3.8.1. Even though Test Classpath was set to depend on JUnit 4, it was too late.

testng dependency was located in my POM:

<dependency>
  <groupId>org.testng</groupId>
  <artifactId>testng</artifactId>
  <version>5.8</version>
  <scope>test</scope>
  <classifier>jdk15</classifier>
</dependency>

Immediately after I have commented it out, tests started to execute.

Lessons learned:

mvn dependency:tree is not always enough, mvn -X is a friend.
surefire is not made for developer heaven (I have realized this while looking at project JIRA reports). This is especially true as there are no other alternatives if you use Maven.

Thanks everybody for your help. Unfortunately there is no way to split answer points between Pascal and Kaleb, but Kaleb's advice to use mvn -X helped me to get on the right track so correct answer points go to him.