more certainty for resuming the paused emitter (microsoft#251130)

Author: amunger

extensions/ipynb/src/test/clearOutputs.test.ts

@@ -25,7 +25,7 @@ suite(`ipynb Clear Outputs`, () => {
 		await vscode.commands.executeCommand('workbench.action.closeAllEditors');
 	});
 
-	test.skip('Clear outputs after opening Notebook', async () => {
+	test('Clear outputs after opening Notebook', async () => {
 		const cells: nbformat.ICell[] = [
 			{
 				cell_type: 'code',

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

@@ -327,7 +327,7 @@ export class ExtHostNotebookController implements ExtHostNotebookShape {
 		}
 
 		if (document.versionId !== versionId) {
-			throw new Error('Document version mismatch');
+			throw new Error('Document version mismatch, expected: ' + versionId + ', actual: ' + document.versionId);
 		}
 
 		if (!this._extHostFileSystem.value.isWritableFileSystem(uri.scheme)) {

src/vs/workbench/contrib/notebook/common/model/notebookTextModel.ts

@@ -49,8 +49,8 @@ class StackOperation implements IWorkspaceUndoRedoElement {
 	constructor(
 		readonly textModel: NotebookTextModel,
 		readonly undoRedoGroup: UndoRedoGroup | undefined,
-		private _pauseableEmitter: PauseableEmitter<NotebookTextModelChangedEvent>,
-		private _postUndoRedo: (alternativeVersionId: string) => void,
+		private readonly _pauseableEmitter: PauseableEmitter<NotebookTextModelChangedEvent>,
+		private readonly _postUndoRedo: (alternativeVersionId: string) => void,
 		selectionState: ISelectionState | undefined,
 		beginAlternativeVersionId: string
 	) {
@@ -621,32 +621,35 @@ export class NotebookTextModel extends Disposable implements INotebookTextModel
 
 	applyEdits(rawEdits: ICellEditOperation[], synchronous: boolean, beginSelectionState: ISelectionState | undefined, endSelectionsComputer: () => ISelectionState | undefined, undoRedoGroup: UndoRedoGroup | undefined, computeUndoRedo: boolean): boolean {
 		this._pauseableEmitter.pause();
-		this._operationManager.pushStackElement(this._alternativeVersionId, undefined);
+		try {
+			this._operationManager.pushStackElement(this._alternativeVersionId, undefined);
 
-		if (computeUndoRedo && this.isOnlyEditingMetadataOnNewCells(rawEdits)) {
-			if (!this._operationManager.appendPreviousOperation()) {
-				// we can't append the previous operation, so just don't compute undo/redo
-				computeUndoRedo = false;
+			if (computeUndoRedo && this.isOnlyEditingMetadataOnNewCells(rawEdits)) {
+				if (!this._operationManager.appendPreviousOperation()) {
+					// we can't append the previous operation, so just don't compute undo/redo
+					computeUndoRedo = false;
+				}
+			} else if (computeUndoRedo) {
+				this.newCellsFromLastEdit.clear();
 			}
-		} else if (computeUndoRedo) {
-			this.newCellsFromLastEdit.clear();
-		}
 
-		try {
-			this._doApplyEdits(rawEdits, synchronous, computeUndoRedo, beginSelectionState, undoRedoGroup);
-			return true;
-		} finally {
-			if (!this._pauseableEmitter.isEmpty) {
-				// Update selection and versionId after applying edits.
-				const endSelections = endSelectionsComputer();
-				this._increaseVersionId(this._operationManager.isUndoStackEmpty() && !this._pauseableEmitter.isDirtyEvent());
+			try {
+				this._doApplyEdits(rawEdits, synchronous, computeUndoRedo, beginSelectionState, undoRedoGroup);
+				return true;
+			} finally {
+				if (!this._pauseableEmitter.isEmpty) {
+					// Update selection and versionId after applying edits.
+					const endSelections = endSelectionsComputer();
+					this._increaseVersionId(this._operationManager.isUndoStackEmpty() && !this._pauseableEmitter.isDirtyEvent());
 
-				// Finalize undo element
-				this._operationManager.pushStackElement(this._alternativeVersionId, endSelections);
+					// Finalize undo element
+					this._operationManager.pushStackElement(this._alternativeVersionId, endSelections);
 
-				// Broadcast changes
-				this._pauseableEmitter.fire({ rawEvents: [], versionId: this.versionId, synchronous: synchronous, endSelectionState: endSelections });
+					// Broadcast changes
+					this._pauseableEmitter.fire({ rawEvents: [], versionId: this.versionId, synchronous: synchronous, endSelectionState: endSelections });
+				}
 			}
+		} finally {
 			this._pauseableEmitter.resume();
 		}
 	}