[ui] support keyword hover for enum keywords

plugins/org.eclipse.etrice.core.common.ui/src/org/eclipse/etrice/core/common/ui/hover/KeywordEObjectTextHover.java

@@ -19,6 +19,7 @@ import org.eclipse.emf.ecore.EObject;
 import org.eclipse.jface.text.IRegion;
 import org.eclipse.jface.text.ITextViewer;
 import org.eclipse.jface.text.Region;
+import org.eclipse.xtext.EnumLiteralDeclaration;
 import org.eclipse.xtext.Keyword;
 import org.eclipse.xtext.nodemodel.ILeafNode;
 import org.eclipse.xtext.nodemodel.util.NodeModelUtils;
@@ -32,7 +33,7 @@ import org.eclipse.xtext.util.Tuples;
 import com.google.inject.Inject;
 
 public class KeywordEObjectTextHover extends DispatchingEObjectTextHover {
-	
+
 	@Inject
 	protected IEObjectHoverProvider hoverProvider;
 
@@ -58,15 +59,26 @@ public class KeywordEObjectTextHover extends DispatchingEObjectTextHover {
 	public Pair<EObject, IRegion> resolveKeywordAt(XtextResource resource, int offset) {
 		IParseResult parseResult = resource.getParseResult();
 		if (parseResult != null) {
-			ILeafNode leaf = NodeModelUtils.findLeafNodeAtOffset(parseResult.getRootNode(), offset);
-			if (leaf != null && leaf.isHidden() && leaf.getOffset() == offset) {
-				leaf = NodeModelUtils.findLeafNodeAtOffset(parseResult.getRootNode(), offset - 1);
-			}
-			if (leaf != null && leaf.getGrammarElement() instanceof Keyword) {
-				Keyword keyword = (Keyword) leaf.getGrammarElement();
-				return Tuples.create((EObject) keyword, (IRegion) new Region(leaf.getOffset(), leaf.getLength()));
+			ILeafNode leaf = findNearestLeafNode(parseResult, offset);
+			if (leaf != null) {
+				if (leaf.getGrammarElement() instanceof Keyword) {
+					Keyword keyword = (Keyword) leaf.getGrammarElement();
+					return Tuples.create((EObject) keyword, (IRegion) new Region(leaf.getOffset(), leaf.getLength()));
+				} else if (leaf.getGrammarElement() instanceof EnumLiteralDeclaration) {
+					Keyword keyword = ((EnumLiteralDeclaration) leaf.getGrammarElement()).getLiteral();
+					return Tuples.create((EObject) keyword, (IRegion) new Region(leaf.getOffset(), leaf.getLength()));
+				}
 			}
+
 		}
 		return null;
 	}
+
+	private ILeafNode findNearestLeafNode(IParseResult parseResult, int offset) {
+		ILeafNode leaf = NodeModelUtils.findLeafNodeAtOffset(parseResult.getRootNode(), offset);
+		if (leaf != null && leaf.isHidden() && leaf.getOffset() == offset) {
+			leaf = NodeModelUtils.findLeafNodeAtOffset(parseResult.getRootNode(), offset - 1);
+		}
+		return leaf;
+	}
 }