Fail assumption when symlinks not supported

Author: mkarg

src/test/java/org/apache/maven/plugins/dependency/fromConfiguration/TestCopyMojo.java

@@ -19,6 +19,8 @@
  * under the License.    
  */
 
+import static org.junit.Assume.assumeTrue;
+
 import java.io.File;
 import java.io.IOException;
 import java.nio.file.Files;
@@ -155,6 +157,23 @@ public void assertFileExists( ArtifactItem item, boolean exist )
         assertEquals( exist, file.exists() );
     }
 
+    private static final boolean supportsSymbolicLinks = supportsSymbolicLinks();
+
+    private static boolean supportsSymbolicLinks( )
+    {
+        try {
+            Path target = Files.createTempFile(null, null);
+            Path link = Files.createTempFile(null, null);
+            Files.delete(link);
+            Files.createSymbolicLink(target, link);
+            Files.delete(link);
+            Files.delete(target);
+            return true;
+        } catch ( Exception e ) {
+            return false;
+        }
+    }
+
     public void assertFilesAreLinks( Collection<ArtifactItem> items, boolean areLinks )
     {
         for ( ArtifactItem item : items )
@@ -268,6 +287,8 @@ public void testCopyToLocation()
     public void testLink()
         throws Exception
     {
+        assumeTrue("supports symbolic links", supportsSymbolicLinks);
+
         List<ArtifactItem> list = stubFactory.getArtifactItems( stubFactory.getClassifiedArtifacts() );
 
         mojo.setArtifactItems( createArtifactItemArtifacts( list ) );