Merge pull request #730 from vjuranek/label_cast_exception

[FIXED JENKINS-17128] Unquote labels before processing

core/src/main/java/jenkins/model/Jenkins.java

@@ -1570,6 +1570,7 @@ public class Jenkins extends AbstractCIBase implements ModifiableTopLevelItemGro
      */
     public Label getLabel(String expr) {
         if(expr==null)  return null;
+        expr = hudson.util.QuotedStringTokenizer.unquote(expr);
         while(true) {
             Label l = labels.get(expr);
             if(l!=null)

test/src/test/java/hudson/model/labels/LabelExpressionTest.java

@@ -196,6 +196,10 @@ public class LabelExpressionTest extends HudsonTestCase {
     public void testQuote() {
         Label l = jenkins.getLabel("\"abc\\\\\\\"def\"");
         assertEquals("abc\\\"def",l.getName());
+        
+        l = jenkins.getLabel("label1||label2"); // create label expression
+        l = jenkins.getLabel("\"label1||label2\"");
+        assertEquals("label1||label2",l.getName());
     }
 
     /**