Fixes #6478: Cancel drag-select or drag-and-drop if a non modifier key is pressed

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

@@ -265,20 +265,18 @@ export class MouseHandler extends ViewEventHandler {
 
 class MouseDownOperation extends Disposable {
 
-	private _context: ViewContext;
-	private _viewController: ViewController;
-	private _viewHelper: IPointerHandlerHelper;
-	private _createMouseTarget: (e: EditorMouseEvent, testEventTarget: boolean) => editorBrowser.IMouseTarget;
-	private _getMouseColumn: (e: EditorMouseEvent) => number;
+	private readonly _context: ViewContext;
+	private readonly _viewController: ViewController;
+	private readonly _viewHelper: IPointerHandlerHelper;
+	private readonly _createMouseTarget: (e: EditorMouseEvent, testEventTarget: boolean) => editorBrowser.IMouseTarget;
+	private readonly _getMouseColumn: (e: EditorMouseEvent) => number;
 
-	private _mouseMoveMonitor: GlobalEditorMouseMoveMonitor;
+	private readonly _mouseMoveMonitor: GlobalEditorMouseMoveMonitor;
+	private readonly _onScrollTimeout: TimeoutTimer;
+	private readonly _mouseState: MouseDownState;
 
 	private _currentSelection: Selection;
-	private _mouseState: MouseDownState;
-
-	private _onScrollTimeout: TimeoutTimer;
 	private _isActive: boolean;
-
 	private _lastMouseEvent: EditorMouseEvent;
 
 	constructor(
@@ -295,15 +293,13 @@ class MouseDownOperation extends Disposable {
 		this._createMouseTarget = createMouseTarget;
 		this._getMouseColumn = getMouseColumn;
 
-		this._currentSelection = new Selection(1, 1, 1, 1);
+		this._mouseMoveMonitor = this._register(new GlobalEditorMouseMoveMonitor(this._viewHelper.viewDomNode));
+		this._onScrollTimeout = this._register(new TimeoutTimer());
 		this._mouseState = new MouseDownState();
 
-		this._onScrollTimeout = this._register(new TimeoutTimer());
+		this._currentSelection = new Selection(1, 1, 1, 1);
 		this._isActive = false;
-
 		this._lastMouseEvent = null;
-
-		this._mouseMoveMonitor = this._register(new GlobalEditorMouseMoveMonitor(this._viewHelper.viewDomNode));
 	}
 
 	public dispose(): void {

src/vs/editor/browser/editorDom.ts

@@ -146,17 +146,35 @@ export class GlobalEditorMouseMoveMonitor extends Disposable {
 
 	private _editorViewDomNode: HTMLElement;
 	private _globalMouseMoveMonitor: GlobalMouseMoveMonitor<EditorMouseEvent>;
+	private _keydownListener: IDisposable;
 
 	constructor(editorViewDomNode: HTMLElement) {
 		super();
 		this._editorViewDomNode = editorViewDomNode;
 		this._globalMouseMoveMonitor = this._register(new GlobalMouseMoveMonitor<EditorMouseEvent>());
+		this._keydownListener = null;
 	}
 
 	public startMonitoring(merger: EditorMouseEventMerger, mouseMoveCallback: (e: EditorMouseEvent) => void, onStopCallback: () => void): void {
+
+		// Add a <<capture>> keydown event listener that will cancel the monitoring
+		// if something other than a modifier key is pressed
+		this._keydownListener = dom.addStandardDisposableListener(<any>document, 'keydown', (e) => {
+			const kb = e.toKeybinding();
+			if (kb.isModifierKey()) {
+				// Allow modifier keys
+				return;
+			}
+			this._globalMouseMoveMonitor.stopMonitoring(true);
+		}, true);
+
 		let myMerger: dom.IEventMerger<EditorMouseEvent> = (lastEvent: EditorMouseEvent, currentEvent: MouseEvent): EditorMouseEvent => {
 			return merger(lastEvent, new EditorMouseEvent(currentEvent, this._editorViewDomNode));
 		};
-		this._globalMouseMoveMonitor.startMonitoring(myMerger, mouseMoveCallback, onStopCallback);
+
+		this._globalMouseMoveMonitor.startMonitoring(myMerger, mouseMoveCallback, () => {
+			this._keydownListener.dispose();
+			onStopCallback();
+		});
 	}
 }