YANG construct collision detection framework added

Change-Id: I1458f9e3192641f3f90c444798c31a64536ffa5d
diff --git a/utils/yangutils/src/test/java/org/onosproject/yangutils/parser/impl/listeners/ContainerListenerTest.java b/utils/yangutils/src/test/java/org/onosproject/yangutils/parser/impl/listeners/ContainerListenerTest.java
index aa86c51..961e902 100644
--- a/utils/yangutils/src/test/java/org/onosproject/yangutils/parser/impl/listeners/ContainerListenerTest.java
+++ b/utils/yangutils/src/test/java/org/onosproject/yangutils/parser/impl/listeners/ContainerListenerTest.java
@@ -69,6 +69,42 @@
     }
 
     /**
+     * Checks if container identifier in module is duplicate.
+     */
+    @Test(expected = ParserException.class)
+    public void processModuleDuplicateContainer() throws IOException, ParserException {
+
+        YangNode node = manager.getDataModel("src/test/resources/ModuleDuplicateContainer.yang");
+    }
+
+    /**
+     * Checks if container identifier in container is duplicate.
+     */
+    @Test(expected = ParserException.class)
+    public void processContainerDuplicateContainer() throws IOException, ParserException {
+
+        YangNode node = manager.getDataModel("src/test/resources/ContainerDuplicateContainer.yang");
+    }
+
+    /**
+     * Checks if container identifier in list is duplicate.
+     */
+    @Test(expected = ParserException.class)
+    public void processListDuplicateContainer() throws IOException, ParserException {
+
+        YangNode node = manager.getDataModel("src/test/resources/ListDuplicateContainer.yang");
+    }
+
+    /**
+     * Checks if container identifier collides with list at same level.
+     */
+    @Test(expected = ParserException.class)
+    public void processDuplicateContainerAndList() throws IOException, ParserException {
+
+        YangNode node = manager.getDataModel("src/test/resources/DuplicateContainerAndList.yang");
+    }
+
+    /**
      * Checks container statement as sub-statement of container.
      */
     @Test
@@ -170,7 +206,7 @@
     @Test
     public void processContainerSubStatementCardinality() throws IOException, ParserException {
         thrown.expect(ParserException.class);
-        thrown.expectMessage("Internal parser error detected: Invalid cardinality in reference before processing.");
+        thrown.expectMessage("YANG file error: Invalid cardinality of reference in container \"valid\".");
         YangNode node = manager.getDataModel("src/test/resources/ContainerSubStatementCardinality.yang");
     }
 
@@ -193,4 +229,4 @@
         thrown.expectMessage("mismatched input '1valid' expecting IDENTIFIER");
         YangNode node = manager.getDataModel("src/test/resources/ContainerInvalidIdentifier.yang");
     }
-}
\ No newline at end of file
+}