Coordinate writing to the textarea, do it after rendering the lines text

src/vs/editor/browser/controller/keyboardHandler.ts

@@ -312,8 +312,9 @@ export class KeyboardHandler extends ViewEventHandler implements IDisposable {
 		return false;
 	}
 
+	private _lastCursorSelectionChanged:editorCommon.IViewCursorSelectionChangedEvent = null;
 	public onCursorSelectionChanged(e:editorCommon.IViewCursorSelectionChangedEvent): boolean {
-		this.textAreaHandler.setCursorSelections(e.selection, e.secondarySelections);
+		this._lastCursorSelectionChanged = e;
 		return false;
 	}
 
@@ -328,4 +329,12 @@ export class KeyboardHandler extends ViewEventHandler implements IDisposable {
 		return false;
 	}
 
+	public writeToTextArea(): void {
+		if (this._lastCursorSelectionChanged) {
+			let e = this._lastCursorSelectionChanged;
+			this._lastCursorSelectionChanged = null;
+			this.textAreaHandler.setCursorSelections(e.selection, e.secondarySelections);
+		}
+	}
+
 }

src/vs/editor/browser/view/viewImpl.ts

@@ -889,6 +889,7 @@ export class View extends ViewEventHandler implements editorBrowser.IView, IDisp
 
 		if (!this.viewLines.shouldRender() && viewPartsToRender.length === 0) {
 			// Nothing to render
+			this.keyboardHandler.writeToTextArea();
 			t.stop();
 			return;
 		}
@@ -896,11 +897,15 @@ export class View extends ViewEventHandler implements editorBrowser.IView, IDisp
 		let linesViewportData = this.layoutProvider.getLinesViewportData();
 
 		if (this.viewLines.shouldRender()) {
-			this.viewLines.renderText(linesViewportData);
+			this.viewLines.renderText(linesViewportData, () => {
+				this.keyboardHandler.writeToTextArea();
+			});
 			this.viewLines.onDidRender();
 
 			// Rendering of viewLines might cause scroll events to occur, so collect view parts to render again
 			viewPartsToRender = this._getViewPartsToRender();
+		} else {
+			this.keyboardHandler.writeToTextArea();
 		}
 
 		let renderingContext = this.createRenderingContext(linesViewportData);

src/vs/editor/browser/viewParts/lines/viewLines.ts

@@ -375,7 +375,7 @@ export class ViewLines extends ViewLayer {
 		throw new Error('Not supported');
 	}
 
-	public renderText(linesViewportData:editorCommon.ViewLinesViewportData): void {
+	public renderText(linesViewportData:editorCommon.ViewLinesViewportData, onAfterLinesRendered:()=>void): void {
 		if (!this.shouldRender()) {
 			throw new Error('I did not ask to render!');
 		}
@@ -387,7 +387,10 @@ export class ViewLines extends ViewLayer {
 		this.domNode.setWidth(this._layoutProvider.getScrollWidth());
 		this.domNode.setHeight(Math.min(this._layoutProvider.getTotalHeight(), 1000000));
 
-		// (2) compute horizontal scroll position:
+		// (2) execute DOM writing that forces sync layout (e.g. textArea manipulation)
+		onAfterLinesRendered();
+
+		// (3) compute horizontal scroll position:
 		//  - this must happen after the lines are in the DOM since it might need a line that rendered just now
 		//  - it might change `scrollWidth` and `scrollLeft`
 		if (this._lastCursorRevealRangeHorizontallyEvent) {
@@ -410,6 +413,7 @@ export class ViewLines extends ViewLayer {
 			this._layoutProvider.setScrollLeft(newScrollLeft.scrollLeft);
 		}
 
+		// (4) handle scrolling
 		let somethingChanged = false;
 		if (browser.canUseTranslate3d) {
 			var transform = 'translate3d(' + -this._layoutProvider.getScrollLeft() + 'px, ' + linesViewportData.visibleRangesDeltaTop + 'px, 0px)';
@@ -418,6 +422,8 @@ export class ViewLines extends ViewLayer {
 			somethingChanged = StyleMutator.setTop(<HTMLElement>this.domNode.domNode.parentNode, linesViewportData.visibleRangesDeltaTop) || somethingChanged; // TODO@Alex
 			somethingChanged = StyleMutator.setLeft(<HTMLElement>this.domNode.domNode.parentNode, -this._layoutProvider.getScrollLeft()) || somethingChanged; // TODO@Alex
 		}
+
+		// (5) reset cached client rect left if scrolling changed something
 		if (somethingChanged) {
 			this._lastRenderedData.resetDomNodeClientRectLeft();
 		}