don't show outline when there are more then 7500 symbols, #50575

src/vs/workbench/parts/outline/electron-browser/outlinePanel.ts

@@ -375,20 +375,25 @@ export class OutlinePanel extends ViewsViewletPanel {
  return this._showMessage(localize('no-editor', "There are no editors open that can provide outline information."));
  }
 
- dom.removeClass(this._domNode, 'message');
 
  let textModel = editor.getModel();
  let model = await asDisposablePromise(OutlineModel.create(textModel), undefined, this._editorDisposables).promise;
  if (!model) {
  return;
  }
 
+ let newSize = TreeElement.size(model);
+ if (newSize > 7500) {
+ // this is a workaround for performance issues with the tree: https://github.com/Microsoft/vscode/issues/18180
+ return this._showMessage(localize('too-many-symbols', "We are sorry, but this file is too large for showing an outline."));
+ }
+
+ dom.removeClass(this._domNode, 'message');
  let oldModel = <OutlineModel>this._tree.getInput();
 
  if (event && oldModel) {
  // heuristic: when the symbols-to-lines ratio changes by 50% between edits
  // wait a little (and hope that the next change isn't as drastic).
- let newSize = TreeElement.size(model);
  let newLength = textModel.getValueLength();
  let newRatio = newSize / newLength;
  let oldSize = TreeElement.size(oldModel);