language-server: hover over function keyword displays info

Unlike variables, functions aren't required to have names, so the function keyword is used in place of the name. similar behavior was observed in TypeScript.

Author: joshtynjala

language-server/src/main/java/com/as3mxml/vscode/providers/HoverProvider.java

@@ -39,11 +39,14 @@
 import org.apache.royale.compiler.internal.mxml.MXMLData;
 import org.apache.royale.compiler.internal.mxml.MXMLDialect;
 import org.apache.royale.compiler.mxml.IMXMLTagData;
+import org.apache.royale.compiler.tree.ASTNodeID;
 import org.apache.royale.compiler.tree.as.IASNode;
 import org.apache.royale.compiler.tree.as.IClassNode;
 import org.apache.royale.compiler.tree.as.IExpressionNode;
 import org.apache.royale.compiler.tree.as.IFunctionCallNode;
+import org.apache.royale.compiler.tree.as.IFunctionNode;
 import org.apache.royale.compiler.tree.as.IIdentifierNode;
+import org.apache.royale.compiler.tree.as.IKeywordNode;
 import org.apache.royale.compiler.tree.as.ILanguageIdentifierNode;
 import org.apache.royale.compiler.tree.metadata.IEventTagNode;
 import org.apache.royale.compiler.tree.metadata.IInspectableTagNode;
@@ -309,6 +312,14 @@ private Hover actionScriptHover(IASNode offsetNode, ILspProject project) {
             }
         }
 
+        if (definition == null && parentNode instanceof IFunctionNode && offsetNode instanceof IKeywordNode) {
+            IKeywordNode keywordNode = (IKeywordNode) offsetNode;
+            if (ASTNodeID.KeywordFunctionID.equals(keywordNode.getNodeID())) {
+                IFunctionNode functionNode = (IFunctionNode) parentNode;
+                definition = functionNode.getDefinition();
+            }
+        }
+
         if (definition == null) {
             return new Hover(Collections.emptyList(), null);
         }