Show message on empty directory

Closes #191

Author: nrc

static/dirView.tsx

@@ -19,7 +19,7 @@ export interface DirViewProps {
 
 export const DirView: React.SFC<DirViewProps> = (props) => {
     const dirPath = props.path.join('/').replace('//', '/');
-    let files = props.files.map((f: any) => {
+    let files: any = props.files.map((f: any) => {
         const onClick = () => props.app.loadSource(`${dirPath}/${f.name}`);
         const className = f.kind === "Directory" ? 'div_entry_name div_dir_entry' : 'div_entry_name div_file_entry';
         return (
@@ -28,6 +28,9 @@ export const DirView: React.SFC<DirViewProps> = (props) => {
             </div>
         );
     });
+    if (files.length == 0) {
+        files = <div className="div_entry">&lt;Empty directory&gt;</div>
+    }
     return <div id="src">
         <BreadCrumbs path={props.path} app={props.app} />
         <div id="div_dir_view">

static/rustw.out.js

@@ -36859,6 +36859,9 @@ exports.DirView = (props) => {
         return (React.createElement("div", { className: "div_entry", key: f.name },
             React.createElement("span", { className: className, onClick: onClick }, f.name)));
     });
+    if (files.length == 0) {
+        files = React.createElement("div", { className: "div_entry" }, "<Empty directory>");
+    }
     return React.createElement("div", { id: "src" },
         React.createElement(breadCrumbs_1.BreadCrumbs, { path: props.path, app: props.app }),
         React.createElement("div", { id: "div_dir_view" },