Unsplit terminals

Fixes #121278

src/vs/workbench/contrib/terminal/browser/terminal.ts

@@ -72,6 +72,7 @@ export interface ITerminalGroup {
 	resizePanes(relativeSizes: number[]): void;
 	setActiveInstanceByIndex(index: number): void;
 	attachToElement(element: HTMLElement): void;
+	removeInstance(instance: ITerminalInstance): void;
 	setVisible(visible: boolean): void;
 	layout(width: number, height: number): void;
 	addDisposable(disposable: IDisposable): void;
@@ -143,6 +144,7 @@ export interface ITerminalService {
 	getActiveOrCreateInstance(): ITerminalInstance;
 	splitInstance(instance: ITerminalInstance, shell?: IShellLaunchConfig, cwd?: string | URI): ITerminalInstance | null;
 	splitInstance(instance: ITerminalInstance, profile: ITerminalProfile): ITerminalInstance | null;
+	unsplitInstance(instance: ITerminalInstance): void;
 
 	/**
 	 * Perform an action with the active terminal instance, if the terminal does
@@ -524,6 +526,8 @@ export interface ITerminalInstance {
 	 */
 	attachToElement(container: HTMLElement): Promise<void> | void;
 
+	detachFromElement(): void;
+
 	/**
 	 * Configure the dimensions of the terminal instance.
 	 *

src/vs/workbench/contrib/terminal/browser/terminalActions.ts

@@ -1395,6 +1395,21 @@ export function registerTerminalActions() {
 			return undefined;
 		}
 	});
+	registerAction2(class extends Action2 {
+		constructor() {
+			super({
+				id: TerminalCommandId.Unsplit,
+				title: { value: localize('workbench.action.terminal.unsplit', "Unsplit Terminal"), original: 'Unsplit Terminal' },
+				f1: true,
+				category,
+				precondition: KEYBINDING_CONTEXT_TERMINAL_PROCESS_SUPPORTED
+			});
+		}
+		async run(accessor: ServicesAccessor) {
+			const terminalService = accessor.get(ITerminalService);
+			await terminalService.doWithActiveInstance(async t => terminalService.unsplitInstance(t));
+		}
+	});
 	registerAction2(class extends Action2 {
 		constructor() {
 			super({

src/vs/workbench/contrib/terminal/browser/terminalGroup.ts

@@ -5,7 +5,7 @@
 
 import { TERMINAL_VIEW_ID } from 'vs/workbench/contrib/terminal/common/terminal';
 import { Event, Emitter } from 'vs/base/common/event';
-import { IDisposable, Disposable, DisposableStore } from 'vs/base/common/lifecycle';
+import { IDisposable, Disposable, DisposableStore, dispose } from 'vs/base/common/lifecycle';
 import { SplitView, Orientation, IView, Sizing } from 'vs/base/browser/ui/splitview/splitview';
 import { IWorkbenchLayoutService, Parts, Position } from 'vs/workbench/services/layout/browser/layoutService';
 import { IInstantiationService } from 'vs/platform/instantiation/common/instantiation';
@@ -233,6 +233,7 @@ export class TerminalGroup extends Disposable implements ITerminalGroup {
 	private _groupElement: HTMLElement | undefined;
 	private _panelPosition: Position = Position.BOTTOM;
 	private _terminalLocation: ViewContainerLocation = ViewContainerLocation.Panel;
+	private _instanceDisposables: Map<number, IDisposable[]> = new Map();
 
 	private _activeInstanceIndex: number;
 	private _isVisible: boolean = false;
@@ -317,8 +318,10 @@ export class TerminalGroup extends Disposable implements ITerminalGroup {
 	}
 
 	private _initInstanceListeners(instance: ITerminalInstance): void {
-		instance.addDisposable(instance.onDisposed(instance => this._onInstanceDisposed(instance)));
-		instance.addDisposable(instance.onFocused(instance => this._setActiveInstance(instance)));
+		this._instanceDisposables.set(instance.instanceId, [
+			instance.onDisposed(instance => this._onInstanceDisposed(instance)),
+			instance.onFocused(instance => this._setActiveInstance(instance))
+		]);
 	}
 
 	private _onInstanceDisposed(instance: ITerminalInstance): void {
@@ -408,6 +411,42 @@ export class TerminalGroup extends Disposable implements ITerminalGroup {
 		this.setVisible(this._isVisible);
 	}
 
+	removeInstance(instance: ITerminalInstance): void {
+		const index = this._terminalInstances.indexOf(instance);
+		if (index === -1) {
+			return;
+		}
+
+		const wasActiveInstance = instance === this.activeInstance;
+		this._terminalInstances.splice(index, 1);
+		instance.detachFromElement();
+
+		// TODO: Share code with onInstanceDisposed
+		// Adjust focus if the instance was active
+		if (wasActiveInstance && this._terminalInstances.length > 0) {
+			const newIndex = index < this._terminalInstances.length ? index : this._terminalInstances.length - 1;
+			this.setActiveInstanceByIndex(newIndex);
+			// TODO: Only focus the new instance if the group had focus?
+			if (this.activeInstance) {
+				this.activeInstance.focus(true);
+			}
+		} else if (index < this._activeInstanceIndex) {
+			// Adjust active instance index if needed
+			this._activeInstanceIndex--;
+		}
+
+		this._splitPaneContainer?.remove(instance);
+
+		// Dispose listeners
+		const disposables = this._instanceDisposables.get(instance.instanceId);
+		if (disposables) {
+			dispose(disposables);
+			this._instanceDisposables.delete(instance.instanceId);
+		}
+
+		this._onInstancesChanged.fire();
+	}
+
 	get title(): string {
 		if (this._terminalInstances.length === 0) {
 			// Normally consumers should not call into title at all after the group is disposed but

src/vs/workbench/contrib/terminal/browser/terminalInstance.ts

@@ -604,6 +604,16 @@ export class TerminalInstance extends Disposable implements ITerminalInstance {
 		this._container.appendChild(this._wrapperElement);
 	}
 
+	detachFromElement(): void {
+		if (!this._wrapperElement) {
+			return;
+		}
+		this._container?.removeChild(this._wrapperElement);
+		this._wrapperElement = undefined;
+
+		// TODO: Don't allow reattach init of xterm
+	}
+
 	private async _attachToElement(container: HTMLElement): Promise<void> {
 		if (this._wrapperElement) {
 			throw new Error('The terminal instance has already been attached to a container');
@@ -900,7 +910,6 @@ export class TerminalInstance extends Disposable implements ITerminalInstance {
 
 	override dispose(immediate?: boolean): void {
 		this._logService.trace(`terminalInstance#dispose (instanceId: ${this.instanceId})`);
-
 		dispose(this._linkManager);
 		this._linkManager = undefined;
 		dispose(this._commandTrackerAddon);
@@ -921,7 +930,11 @@ export class TerminalInstance extends Disposable implements ITerminalInstance {
 		if (this._xterm) {
 			const buffer = this._xterm.buffer;
 			this._sendLineData(buffer.active, buffer.active.baseY + buffer.active.cursorY);
-			this._xterm.dispose();
+			try {
+				this._xterm.dispose();
+			} catch {
+				// No op, exception may get thrown from removeChild
+			}
 		}
 
 		if (this._pressAnyKeyToCloseListener) {

src/vs/workbench/contrib/terminal/browser/terminalService.ts

@@ -621,6 +621,23 @@ export class TerminalService implements ITerminalService {
 		return instance;
 	}
 
+	unsplitInstance(instance: ITerminalInstance): void {
+		const oldGroup = this.getGroupForInstance(instance);
+		if (!oldGroup || oldGroup.terminalInstances.length < 2) {
+			return;
+		}
+
+		oldGroup.removeInstance(instance);
+
+		const newGroup = this._instantiationService.createInstance(TerminalGroup, this._terminalContainer, instance);
+		newGroup.onPanelOrientationChanged((orientation) => this._onPanelOrientationChanged.fire(orientation));
+		this._terminalGroups.push(newGroup);
+
+		newGroup.addDisposable(newGroup.onDisposed(this._onGroupDisposed.fire, this._onGroupDisposed));
+		newGroup.addDisposable(newGroup.onInstancesChanged(this._onInstancesChanged.fire, this._onInstancesChanged));
+		this._onInstancesChanged.fire();
+	}
+
 	protected _initInstanceListeners(instance: ITerminalInstance): void {
 		instance.addDisposable(instance.onDisposed(this._onInstanceDisposed.fire, this._onInstanceDisposed));
 		instance.addDisposable(instance.onTitleChanged(this._onInstanceTitleChanged.fire, this._onInstanceTitleChanged));
@@ -969,6 +986,7 @@ export class TerminalService implements ITerminalService {
 		instance.shellLaunchConfig.hideFromUser = false;
 		const terminalGroup = this._instantiationService.createInstance(TerminalGroup, this._terminalContainer, instance);
 		this._terminalGroups.push(terminalGroup);
+		terminalGroup.onPanelOrientationChanged((orientation) => this._onPanelOrientationChanged.fire(orientation));
 		terminalGroup.addDisposable(terminalGroup.onDisposed(this._onGroupDisposed.fire, this._onGroupDisposed));
 		terminalGroup.addDisposable(terminalGroup.onInstancesChanged(this._onInstancesChanged.fire, this._onInstancesChanged));
 		if (this.terminalInstances.length === 1) {

src/vs/workbench/contrib/terminal/common/terminal.ts

@@ -397,6 +397,7 @@ export const enum TerminalCommandId {
 	Split = 'workbench.action.terminal.split',
 	SplitInstance = 'workbench.action.terminal.splitInstance',
 	SplitInActiveWorkspace = 'workbench.action.terminal.splitInActiveWorkspace',
+	Unsplit = 'workbench.action.terminal.unsplit',
 	Relaunch = 'workbench.action.terminal.relaunch',
 	FocusPreviousPane = 'workbench.action.terminal.focusPreviousPane',
 	ShowTabs = 'workbench.action.terminal.showTabs',