cover the constructor as well (microsoft#250675)

Author: amunger

src/vs/workbench/api/common/extHostNotebookEditor.ts

@@ -18,16 +18,19 @@ export class ExtHostNotebookEditor {
 	private _visible: boolean = false;
 
 	private _editor?: vscode.NotebookEditor;
+	private _selections: vscode.NotebookRange[] = [new NotebookRange(0, 0)];
 
 	constructor(
 		readonly id: string,
 		private readonly _proxy: MainThreadNotebookEditorsShape,
 		readonly notebookData: ExtHostNotebookDocument,
 		private _visibleRanges: vscode.NotebookRange[],
-		private _selections: vscode.NotebookRange[],
+		selections: vscode.NotebookRange[],
 		private _viewColumn: vscode.ViewColumn | undefined,
 		private readonly viewType: string
-	) { }
+	) {
+		this._selections = this._validSelections(selections);
+	}
 
 	get apiEditor(): vscode.NotebookEditor {
 		if (!this._editor) {
@@ -49,7 +52,7 @@ export class ExtHostNotebookEditor {
 					if (!Array.isArray(value) || !value.every(extHostTypes.NotebookRange.isNotebookRange)) {
 						throw illegalArgument('selections');
 					}
-					that._selections = value.length === 0 ? [new NotebookRange(0, 0)] : value;
+					that._selections = that._validSelections(value);
 					that._trySetSelections(that._selections);
 				},
 				get visibleRanges() {
@@ -94,7 +97,7 @@ export class ExtHostNotebookEditor {
 	}
 
 	_acceptSelections(selections: vscode.NotebookRange[]): void {
-		this._selections = selections.length === 0 ? [new NotebookRange(0, 0)] : selections;
+		this._selections = this._validSelections(selections);
 	}
 
 	private _trySetSelections(value: vscode.NotebookRange[]): void {
@@ -104,4 +107,8 @@ export class ExtHostNotebookEditor {
 	_acceptViewColumn(value: vscode.ViewColumn | undefined) {
 		this._viewColumn = value;
 	}
+
+	private _validSelections(selections: vscode.NotebookRange[]) {
+		return selections.length === 0 ? [new NotebookRange(0, 0)] : selections;
+	}
 }