debug: do not rely on focused session when updating viewlet

src/vs/workbench/parts/debug/electron-browser/debugViewer.ts

@@ -354,6 +354,7 @@ export class CallStackDataSource implements tree.IDataSource {
 	}
 
 	public hasChildren(tree: tree.ITree, element: any): boolean {
+		// TODO@isidor also has children if it is a session
 		return element instanceof model.Model || (element instanceof model.Thread && (<model.Thread>element).stopped);
 	}
 
@@ -361,14 +362,12 @@ export class CallStackDataSource implements tree.IDataSource {
 		if (element instanceof model.Thread) {
 			return this.getThreadChildren(element);
 		}
-
-		// TODO@Isidor FIX THIS
-		const session = this.debugService.getViewModel().activeSession;
-		if (!session) {
-			return TPromise.as([]);
+		if (element instanceof model.Model) {
+			return TPromise.as(element.getSessions());
 		}
 
-		const threads = (<model.Model>element).getThreads(session.getId());
+		const session = <debug.IRawDebugSession>element;
+		const threads = this.debugService.getModel().getThreads(session.getId());
 		return TPromise.as(Object.keys(threads).map(ref => threads[ref]));
 	}
 

src/vs/workbench/parts/debug/electron-browser/debugViews.ts

@@ -290,11 +290,14 @@ export class CallStackView extends viewlet.CollapsibleViewletView {
 		}));
 
 		this.toDispose.push(model.onDidChangeCallStack(() => {
-			const session = this.debugService.getViewModel().activeSession;
-			const threads = session ? model.getThreads(session.getId()) : Object.create(null);
-			const threadsArray = Object.keys(threads).map(ref => threads[ref]);
-			// Only show the threads in the call stack if there is more than 1 thread.
-			const newTreeInput = threadsArray.length === 1 ? threadsArray[0] : model;
+			let newTreeInput: any = this.debugService.getModel();
+			const sessions = this.debugService.getModel().getSessions();
+			if (sessions.length === 1) {
+				const threads = sessions[0] ? model.getThreads(sessions[0].getId()) : Object.create(null);
+				const threadsArray = Object.keys(threads).map(ref => threads[ref]);
+				// Only show the threads in the call stack if there is more than 1 thread.
+				newTreeInput = threadsArray.length === 1 ? threadsArray[0] : sessions[0];
+			}
 
 			if (this.tree.getInput() === newTreeInput) {
 				this.tree.refresh().done(null, errors.onUnexpectedError);