[ONOS-3897] Yang Listener for Enumeration Data Type

Change-Id: If257c73da8fe2dcc2f4111f103967cfcdd7fa273
diff --git a/utils/yangutils/src/test/java/org/onosproject/yangutils/parser/impl/listeners/EnumListenerTest.java b/utils/yangutils/src/test/java/org/onosproject/yangutils/parser/impl/listeners/EnumListenerTest.java
new file mode 100644
index 0000000..60de57f
--- /dev/null
+++ b/utils/yangutils/src/test/java/org/onosproject/yangutils/parser/impl/listeners/EnumListenerTest.java
@@ -0,0 +1,81 @@
+/*
+ * Copyright 2014-2016 Open Networking Laboratory
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package org.onosproject.yangutils.parser.impl.listeners;
+
+import static org.hamcrest.MatcherAssert.assertThat;
+import static org.hamcrest.core.Is.is;
+import org.junit.Test;
+import org.onosproject.yangutils.datamodel.YangDataTypes;
+import org.onosproject.yangutils.datamodel.YangEnum;
+import org.onosproject.yangutils.datamodel.YangEnumeration;
+import org.onosproject.yangutils.datamodel.YangLeaf;
+import org.onosproject.yangutils.datamodel.YangModule;
+import org.onosproject.yangutils.datamodel.YangNode;
+import org.onosproject.yangutils.datamodel.YangNodeType;
+import org.onosproject.yangutils.parser.exceptions.ParserException;
+import org.onosproject.yangutils.parser.impl.YangUtilsParserManager;
+
+import java.io.IOException;
+import java.util.ListIterator;
+import java.util.Set;
+
+/**
+ * Test cases for enum listener.
+ */
+public class EnumListenerTest {
+
+    private final YangUtilsParserManager manager = new YangUtilsParserManager();
+
+    /**
+     * Checks enum statement without value.
+     */
+    @Test
+    public void processEnumTypeStatement() throws IOException, ParserException {
+
+        YangNode node = manager.getDataModel("src/test/resources/EnumTypeStatement.yang");
+
+        // Check whether the data model tree returned is of type module.
+        assertThat((node instanceof YangModule), is(true));
+
+        // Check whether the node type is set properly to module.
+        assertThat(node.getNodeType(), is(YangNodeType.MODULE_NODE));
+
+        // Check whether the module name is set correctly.
+        YangModule yangNode = (YangModule) node;
+        assertThat(yangNode.getName(), is("Test"));
+
+        ListIterator<YangLeaf> leafIterator = yangNode.getListOfLeaf().listIterator();
+        YangLeaf leafInfo = leafIterator.next();
+
+        assertThat(leafInfo.getLeafName(), is("speed"));
+        assertThat(leafInfo.getDataType().getDataTypeName(), is("enumeration"));
+        assertThat(leafInfo.getDataType().getDataType(), is(YangDataTypes.ENUMERATION));
+        assertThat(((YangEnumeration) leafInfo.getDataType().getDataTypeExtendedInfo()).getEnumerationName(),
+                is("speed"));
+
+        Set<YangEnum> enumSet = ((YangEnumeration) leafInfo.getDataType().getDataTypeExtendedInfo()).getEnumSet();
+        for (YangEnum tmp : enumSet) {
+            if (tmp.getNamedValue().equals("10m")) {
+                assertThat(tmp.getValue(), is(0));
+            } else if (tmp.getNamedValue().equals("100m")) {
+                assertThat(tmp.getValue(), is(1));
+            } else if (tmp.getNamedValue().equals("auto")) {
+                assertThat(tmp.getValue(), is(2));
+            }
+        }
+    }
+}