🏃 fewer event emitters

src/vs/workbench/contrib/notebook/browser/notebookBrowser.ts

@@ -428,6 +428,8 @@ export interface CellViewModelStateChangeEvent {
 	runStateChanged?: boolean;
 	editStateChanged?: boolean;
 	languageChanged?: boolean;
+	foldingStateChanged?: boolean;
+	contentChanged?: boolean;
 }
 
 /**

src/vs/workbench/contrib/notebook/browser/view/renderers/markdownCell.ts

@@ -131,7 +131,11 @@ export class StatefullMarkdownCell extends Disposable {
 						notebookEditor.layoutNotebookCell(viewCell, clientHeight);
 					}));
 
-					this.localDisposables.add(viewCell.onDidChangeContent(() => {
+					this.localDisposables.add(viewCell.onDidChangeState((e) => {
+						if (!e.contentChanged) {
+							return;
+						}
+
 						this.markdownContainer.innerHTML = '';
 						let renderedHTML = viewCell.getHTML();
 						if (renderedHTML) {
@@ -162,7 +166,11 @@ export class StatefullMarkdownCell extends Disposable {
 		this.foldingState = viewCell.foldingState;
 		this.setFoldingIndicator();
 
-		this._register(viewCell.onDidChangeFoldingState(() => {
+		this._register(viewCell.onDidChangeState((e) => {
+			if (!e.foldingStateChanged) {
+				return;
+			}
+
 			const foldingState = viewCell.foldingState;
 
 			if (foldingState !== this.foldingState) {

src/vs/workbench/contrib/notebook/browser/viewModel/codeCellViewModel.ts

@@ -35,9 +35,6 @@ export class CodeCellViewModel extends BaseCellViewModel implements ICellViewMod
 		return this.model.outputs;
 	}
 
-	private readonly _onDidChangeContent: Emitter<void> = this._register(new Emitter<void>());
-	public readonly onDidChangeContent: Event<void> = this._onDidChangeContent.event;
-
 	protected readonly _onDidChangeLayout = new Emitter<CodeCellLayoutChangeEvent>();
 	readonly onDidChangeLayout = this._onDidChangeLayout.event;
 
@@ -191,7 +188,7 @@ export class CodeCellViewModel extends BaseCellViewModel implements ICellViewMod
 			this._register(ref);
 			this._register(this._textModel.onDidChangeContent(() => {
 				this.model.contentChange();
-				this._onDidChangeContent.fire();
+				this._onDidChangeState.fire({ contentChanged: true });
 			}));
 		}
 

src/vs/workbench/contrib/notebook/browser/viewModel/markdownCellViewModel.ts

@@ -22,9 +22,6 @@ export class MarkdownCellViewModel extends BaseCellViewModel implements ICellVie
 	cellKind: CellKind.Markdown = CellKind.Markdown;
 	private _mdRenderer: MarkdownRenderer | null = null;
 	private _html: HTMLElement | null = null;
-	private readonly _onDidChangeContent: Emitter<void> = this._register(new Emitter<void>());
-	public readonly onDidChangeContent: Event<void> = this._onDidChangeContent.event;
-
 	private _layoutInfo: MarkdownCellLayoutInfo;
 
 	get layoutInfo() {
@@ -42,9 +39,6 @@ export class MarkdownCellViewModel extends BaseCellViewModel implements ICellVie
 	protected readonly _onDidChangeLayout = new Emitter<MarkdownCellLayoutChangeEvent>();
 	readonly onDidChangeLayout = this._onDidChangeLayout.event;
 
-	protected readonly _onDidChangeFoldingState = new Emitter<void>();
-	readonly onDidChangeFoldingState = this._onDidChangeFoldingState.event;
-
 	get foldingState() {
 		return this.foldingDelegate.getFoldingState(this);
 	}
@@ -74,7 +68,7 @@ export class MarkdownCellViewModel extends BaseCellViewModel implements ICellVie
 		}));
 
 		this._register(foldingDelegate.onDidFoldingRegionChanged(() => {
-			this._onDidChangeFoldingState.fire();
+			this._onDidChangeState.fire({ foldingStateChanged: true });
 		}));
 	}
 
@@ -149,7 +143,7 @@ export class MarkdownCellViewModel extends BaseCellViewModel implements ICellVie
 			this._register(this._textModel.onDidChangeContent(() => {
 				this.model.contentChange();
 				this._html = null;
-				this._onDidChangeContent.fire();
+				this._onDidChangeState.fire({ contentChanged: true });
 			}));
 		}
 		return this._textModel;