- Made the TreeItem.children prop optional since the library allows this and prevents verboseness/unneeded empty arrays

- Added 'dom' lib in tsconfig to fix dom errors from definition dependencies when running `tsc`

types/react-sortable-tree/index.d.ts

@@ -15,7 +15,7 @@ export interface TreeItem {
     title?: string;
     subtitle?: string;
     expanded?: boolean;
-    children: TreeItem[];
+    children?: TreeItem[];
     [x: string]: any;
 }
 

types/react-sortable-tree/react-sortable-tree-tests.tsx

@@ -21,7 +21,7 @@ class Test extends React.Component {
             {
                 title: "Title", subtitle: "Subtitle", children: [
                     {title: "Child 1", subtitle: "Subtitle", children: []},
-                    {title: "Child 2", subtitle: "Subtitle", children: []}
+                    {title: "Child 2", subtitle: "Subtitle"}
                 ]
             }
         ];

types/react-sortable-tree/tsconfig.json

@@ -2,7 +2,8 @@
     "compilerOptions": {
         "module": "commonjs",
         "lib": [
-            "es6"
+            "es6",
+            "dom"
         ],
         "noImplicitAny": true,
         "noImplicitThis": true,