Solving MNG-711:

o Added a check in MavenProject.getArtifacts() to never return null,
  but an empty Set, since there's almost no checking.

o Added requiresDependencyResolution test to SurefirePlugin.


git-svn-id: https://svn.apache.org/repos/asf/maven/components/trunk@230827 13f79535-47bb-0310-9956-ffa450edef68

maven-plugins/maven-surefire-plugin/src/main/java/org/apache/maven/test/SurefirePlugin.java

@@ -35,6 +35,7 @@ import java.util.StringTokenizer;
 /**
  * @author <a href="mailto:jason@maven.org">Jason van Zyl</a>
  * @version $Id$
+ * @requiresDependencyResolution test
  * @goal test
  * @phase test
  * @description Run tests using surefire

maven-project/src/main/java/org/apache/maven/project/MavenProject.java

@@ -841,7 +841,7 @@ public class MavenProject
 
     public Set getArtifacts()
     {
-        return artifacts;
+        return artifacts == null ? Collections.EMPTY_SET : artifacts;
     }
 
     public Map getArtifactMap()