Change openEditor to return undefined instead of null

For #70020

src/vs/workbench/contrib/debug/browser/breakpointsView.ts

@@ -543,9 +543,9 @@ class FunctionBreakpointInputRenderer implements IListRenderer<IFunctionBreakpoi
 	}
 }
 
-export function openBreakpointSource(breakpoint: IBreakpoint, sideBySide: boolean, preserveFocus: boolean, debugService: IDebugService, editorService: IEditorService): Promise<IEditor | null> {
+export function openBreakpointSource(breakpoint: IBreakpoint, sideBySide: boolean, preserveFocus: boolean, debugService: IDebugService, editorService: IEditorService): Promise<IEditor | undefined> {
 	if (breakpoint.uri.scheme === DEBUG_SCHEME && debugService.state === State.Inactive) {
-		return Promise.resolve(null);
+		return Promise.resolve(undefined);
 	}
 
 	const selection = breakpoint.endLineNumber ? {

src/vs/workbench/contrib/debug/browser/debugConfigurationManager.ts

@@ -578,7 +578,7 @@ class Launch extends AbstractLaunch implements ILaunch {
 					pinned: created,
 					revealIfVisible: true
 				},
-			}, sideBySide ? SIDE_GROUP : ACTIVE_GROUP).then(editor => ({ editor, created })));
+			}, sideBySide ? SIDE_GROUP : ACTIVE_GROUP).then(editor => ({ editor: withUndefinedAsNull(editor), created })));
 		}, (error: Error) => {
 			throw new Error(nls.localize('DebugConfig.failed', "Unable to create 'launch.json' file inside the '.vscode' folder ({0}).", error.message));
 		});
@@ -614,7 +614,7 @@ class WorkspaceLaunch extends AbstractLaunch implements ILaunch {
 		return this.editorService.openEditor({
 			resource: this.contextService.getWorkspace().configuration!,
 			options: { preserveFocus }
-		}, sideBySide ? SIDE_GROUP : ACTIVE_GROUP).then(editor => ({ editor, created: false }));
+		}, sideBySide ? SIDE_GROUP : ACTIVE_GROUP).then(editor => ({ editor: withUndefinedAsNull(editor), created: false }));
 	}
 }
 

src/vs/workbench/contrib/debug/common/debugSource.ts

@@ -13,6 +13,7 @@ import { IEditorService, SIDE_GROUP, ACTIVE_GROUP } from 'vs/workbench/services/
 import { Schemas } from 'vs/base/common/network';
 import { isUri } from 'vs/workbench/contrib/debug/common/debugUtils';
 import { ITextEditor } from 'vs/workbench/common/editor';
+import { withUndefinedAsNull } from 'vs/base/common/types';
 
 export const UNKNOWN_SOURCE_LABEL = nls.localize('unknownSource', "Unknown Source");
 
@@ -104,7 +105,7 @@ export class Source {
 				revealInCenterIfOutsideViewport: true,
 				pinned: pinned || (!preserveFocus && !this.inMemory)
 			}
-		}, sideBySide ? SIDE_GROUP : ACTIVE_GROUP);
+		}, sideBySide ? SIDE_GROUP : ACTIVE_GROUP).then(withUndefinedAsNull);
 	}
 
 	static getEncodedDebugData(modelUri: uri): { name: string, path: string, sessionId?: string, sourceReference?: number } {

src/vs/workbench/contrib/files/browser/explorerViewlet.ts

@@ -34,6 +34,7 @@ import { ViewletPanel } from 'vs/workbench/browser/parts/views/panelViewlet';
 import { KeyChord, KeyMod, KeyCode } from 'vs/base/common/keyCodes';
 import { Registry } from 'vs/platform/registry/common/platform';
 import { IProgressService, ProgressLocation } from 'vs/platform/progress/common/progress';
+import { withUndefinedAsNull } from 'vs/base/common/types';
 
 export class ExplorerViewletViewsContribution extends Disposable implements IWorkbenchContribution {
 
@@ -202,7 +203,7 @@ export class ExplorerViewlet extends ViewContainerViewlet {
 					openEditorsView.setStructuralRefreshDelay(delay);
 				}
 
-				let openedEditor: IEditor | null = null;
+				let openedEditor: IEditor | undefined;
 				try {
 					openedEditor = await this.editorService.openEditor(editor, options, group);
 				} catch (error) {
@@ -214,7 +215,7 @@ export class ExplorerViewlet extends ViewContainerViewlet {
 					}
 				}
 
-				return openedEditor;
+				return withUndefinedAsNull(openedEditor);
 			});
 
 			const explorerInstantiator = this.instantiationService.createChild(new ServiceCollection([IEditorService, delegatingEditorService]));

src/vs/workbench/contrib/preferences/browser/keyboardLayoutPicker.ts

@@ -158,9 +158,9 @@ export class KeyboardLayoutPickerAction extends Action {
 
 			await this.fileService.resolve(file).then(undefined, (error) => {
 				return this.fileService.createFile(file, VSBuffer.fromString(KeyboardLayoutPickerAction.DEFAULT_CONTENT));
-			}).then((stat): Promise<IEditor | null> | null => {
+			}).then((stat): Promise<IEditor | undefined> | undefined => {
 				if (!stat) {
-					return null;
+					return undefined;
 				}
 				return this.editorService.openEditor({
 					resource: stat.resource,

src/vs/workbench/services/editor/browser/editorService.ts

@@ -216,11 +216,11 @@ export class EditorService extends Disposable implements EditorServiceImpl {
 
 	//#region openEditor()
 
-	openEditor(editor: IEditorInput, options?: IEditorOptions | ITextEditorOptions, group?: IEditorGroup | GroupIdentifier | SIDE_GROUP_TYPE | ACTIVE_GROUP_TYPE): Promise<IEditor | null>;
-	openEditor(editor: IResourceInput | IUntitledResourceInput, group?: IEditorGroup | GroupIdentifier | SIDE_GROUP_TYPE | ACTIVE_GROUP_TYPE): Promise<ITextEditor | null>;
-	openEditor(editor: IResourceDiffInput, group?: IEditorGroup | GroupIdentifier | SIDE_GROUP_TYPE | ACTIVE_GROUP_TYPE): Promise<ITextDiffEditor | null>;
-	openEditor(editor: IResourceSideBySideInput, group?: IEditorGroup | GroupIdentifier | SIDE_GROUP_TYPE | ACTIVE_GROUP_TYPE): Promise<ITextSideBySideEditor | null>;
-	openEditor(editor: IEditorInput | IResourceEditor, optionsOrGroup?: IEditorOptions | ITextEditorOptions | IEditorGroup | GroupIdentifier | SIDE_GROUP_TYPE | ACTIVE_GROUP_TYPE, group?: GroupIdentifier): Promise<IEditor | null> {
+	openEditor(editor: IEditorInput, options?: IEditorOptions | ITextEditorOptions, group?: IEditorGroup | GroupIdentifier | SIDE_GROUP_TYPE | ACTIVE_GROUP_TYPE): Promise<IEditor | undefined>;
+	openEditor(editor: IResourceInput | IUntitledResourceInput, group?: IEditorGroup | GroupIdentifier | SIDE_GROUP_TYPE | ACTIVE_GROUP_TYPE): Promise<ITextEditor | undefined>;
+	openEditor(editor: IResourceDiffInput, group?: IEditorGroup | GroupIdentifier | SIDE_GROUP_TYPE | ACTIVE_GROUP_TYPE): Promise<ITextDiffEditor | undefined>;
+	openEditor(editor: IResourceSideBySideInput, group?: IEditorGroup | GroupIdentifier | SIDE_GROUP_TYPE | ACTIVE_GROUP_TYPE): Promise<ITextSideBySideEditor | undefined>;
+	openEditor(editor: IEditorInput | IResourceEditor, optionsOrGroup?: IEditorOptions | ITextEditorOptions | IEditorGroup | GroupIdentifier | SIDE_GROUP_TYPE | ACTIVE_GROUP_TYPE, group?: GroupIdentifier): Promise<IEditor | undefined> {
 
 		// Typed Editor Support
 		if (editor instanceof EditorInput) {
@@ -240,11 +240,11 @@ export class EditorService extends Disposable implements EditorServiceImpl {
 			return this.doOpenEditor(targetGroup, typedInput, editorOptions);
 		}
 
-		return Promise.resolve(null);
+		return Promise.resolve(undefined);
 	}
 
-	protected doOpenEditor(group: IEditorGroup, editor: IEditorInput, options?: IEditorOptions): Promise<IEditor | null> {
-		return group.openEditor(editor, options);
+	protected doOpenEditor(group: IEditorGroup, editor: IEditorInput, options?: IEditorOptions): Promise<IEditor | undefined> {
+		return group.openEditor(editor, options).then(withNullAsUndefined);
 	}
 
 	private findTargetGroup(input: IEditorInput, options?: IEditorOptions, group?: IEditorGroup | GroupIdentifier | SIDE_GROUP_TYPE | ACTIVE_GROUP_TYPE): IEditorGroup {
@@ -651,7 +651,7 @@ export class DelegatingEditorService extends EditorService {
 		this.editorOpenHandler = handler;
 	}
 
-	protected async doOpenEditor(group: IEditorGroup, editor: IEditorInput, options?: IEditorOptions): Promise<IEditor | null> {
+	protected async doOpenEditor(group: IEditorGroup, editor: IEditorInput, options?: IEditorOptions): Promise<IEditor | undefined> {
 		if (!this.editorOpenHandler) {
 			return super.doOpenEditor(group, editor, options);
 		}

src/vs/workbench/services/editor/common/editorService.ts

@@ -117,13 +117,13 @@ export interface IEditorService {
 	 * active group. Use `SIDE_GROUP_TYPE` to open the editor in a new editor group to the side
 	 * of the currently active group.
 	 *
-	 * @returns the editor that opened or NULL if the operation failed or the editor was not
+	 * @returns the editor that opened or `undefined` if the operation failed or the editor was not
 	 * opened to be active.
 	 */
-	openEditor(editor: IEditorInput, options?: IEditorOptions | ITextEditorOptions, group?: IEditorGroup | GroupIdentifier | SIDE_GROUP_TYPE | ACTIVE_GROUP_TYPE): Promise<IEditor | null>;
-	openEditor(editor: IResourceInput | IUntitledResourceInput, group?: IEditorGroup | GroupIdentifier | SIDE_GROUP_TYPE | ACTIVE_GROUP_TYPE): Promise<ITextEditor | null>;
-	openEditor(editor: IResourceDiffInput, group?: IEditorGroup | GroupIdentifier | SIDE_GROUP_TYPE | ACTIVE_GROUP_TYPE): Promise<ITextDiffEditor | null>;
-	openEditor(editor: IResourceSideBySideInput, group?: IEditorGroup | GroupIdentifier | SIDE_GROUP_TYPE | ACTIVE_GROUP_TYPE): Promise<ITextSideBySideEditor | null>;
+	openEditor(editor: IEditorInput, options?: IEditorOptions | ITextEditorOptions, group?: IEditorGroup | GroupIdentifier | SIDE_GROUP_TYPE | ACTIVE_GROUP_TYPE): Promise<IEditor | undefined>;
+	openEditor(editor: IResourceInput | IUntitledResourceInput, group?: IEditorGroup | GroupIdentifier | SIDE_GROUP_TYPE | ACTIVE_GROUP_TYPE): Promise<ITextEditor | undefined>;
+	openEditor(editor: IResourceDiffInput, group?: IEditorGroup | GroupIdentifier | SIDE_GROUP_TYPE | ACTIVE_GROUP_TYPE): Promise<ITextDiffEditor | undefined>;
+	openEditor(editor: IResourceSideBySideInput, group?: IEditorGroup | GroupIdentifier | SIDE_GROUP_TYPE | ACTIVE_GROUP_TYPE): Promise<ITextSideBySideEditor | undefined>;
 
 	/**
 	 * Open editors in an editor group.

src/vs/workbench/services/history/browser/history.ts

@@ -453,7 +453,7 @@ export class HistoryService extends Disposable implements IHistoryService {
 		this.doNavigate(this.stack[this.index], !acrossEditors).finally(() => this.navigatingInStack = false);
 	}
 
-	private doNavigate(location: IStackEntry, withSelection: boolean): Promise<IBaseEditor | null> {
+	private doNavigate(location: IStackEntry, withSelection: boolean): Promise<IBaseEditor | undefined> {
 		const options: ITextEditorOptions = {
 			revealIfOpened: true // support to navigate across editor groups
 		};

src/vs/workbench/services/preferences/browser/preferencesService.ts

@@ -189,11 +189,11 @@ export class PreferencesService extends Disposable implements IPreferencesServic
 		return null;
 	}
 
-	openRawDefaultSettings(): Promise<IEditor | null> {
+	openRawDefaultSettings(): Promise<IEditor | undefined> {
 		return this.editorService.openEditor({ resource: this.defaultSettingsRawResource });
 	}
 
-	openRawUserSettings(): Promise<IEditor | null> {
+	openRawUserSettings(): Promise<IEditor | undefined> {
 		return this.editorService.openEditor({ resource: this.userSettingsResource });
 	}
 
@@ -232,7 +232,7 @@ export class PreferencesService extends Disposable implements IPreferencesServic
 		const environment = await this.remoteAgentService.getEnvironment();
 		if (environment) {
 			await this.createIfNotExists(environment.settingsPath, emptyEditableSettingsContent);
-			return this.editorService.openEditor({ resource: environment.settingsPath, options: { pinned: true, revealIfOpened: true } }).then(withNullAsUndefined);
+			return this.editorService.openEditor({ resource: environment.settingsPath, options: { pinned: true, revealIfOpened: true } });
 		}
 		return undefined;
 	}
@@ -307,7 +307,7 @@ export class PreferencesService extends Disposable implements IPreferencesServic
 		return this.editorService.openEditor(this.instantiationService.createInstance(KeybindingsEditorInput), { pinned: true, revealIfOpened: true }).then(() => undefined);
 	}
 
-	openDefaultKeybindingsFile(): Promise<IEditor | null> {
+	openDefaultKeybindingsFile(): Promise<IEditor | undefined> {
 		return this.editorService.openEditor({ resource: this.defaultKeybindingsResource, label: nls.localize('defaultKeybindings', "Default Keybindings") });
 	}
 
@@ -368,7 +368,7 @@ export class PreferencesService extends Disposable implements IPreferencesServic
 						this.editorService.openEditor(editableSettingsEditorInput, { pinned: true, revealIfOpened: true }, sideEditorGroup.id)
 					]).then(([defaultEditor, editor]) => withNullAsUndefined(editor));
 				} else {
-					return this.editorService.openEditor(editableSettingsEditorInput, SettingsEditorOptions.create(options), group).then(withNullAsUndefined);
+					return this.editorService.openEditor(editableSettingsEditorInput, SettingsEditorOptions.create(options), group);
 				}
 			});
 	}
@@ -385,7 +385,7 @@ export class PreferencesService extends Disposable implements IPreferencesServic
 				const defaultPreferencesEditorInput = this.instantiationService.createInstance(DefaultPreferencesEditorInput, this.getDefaultSettingsResource(configurationTarget));
 				const preferencesEditorInput = new PreferencesEditorInput(this.getPreferencesEditorInputName(configurationTarget, resource), editableSettingsEditorInput.getDescription(), defaultPreferencesEditorInput, <EditorInput>editableSettingsEditorInput);
 				this.lastOpenedSettingsInput = preferencesEditorInput;
-				return this.editorService.openEditor(preferencesEditorInput, SettingsEditorOptions.create(options), group).then(withNullAsUndefined);
+				return this.editorService.openEditor(preferencesEditorInput, SettingsEditorOptions.create(options), group);
 			});
 	}
 
@@ -401,7 +401,7 @@ export class PreferencesService extends Disposable implements IPreferencesServic
 			folderUri
 		};
 
-		return this.editorService.openEditor(input, SettingsEditorOptions.create(settingsOptions), group).then(withNullAsUndefined);
+		return this.editorService.openEditor(input, SettingsEditorOptions.create(settingsOptions), group);
 	}
 
 	private async doSwitchSettings(target: ConfigurationTarget, resource: URI, input: PreferencesEditorInput, group: IEditorGroup, options?: ISettingsEditorOptions): Promise<IEditor> {

src/vs/workbench/services/preferences/common/preferences.ts

@@ -201,15 +201,15 @@ export interface IPreferencesService {
 	createPreferencesEditorModel<T>(uri: URI): Promise<IPreferencesEditorModel<T> | null>;
 	createSettings2EditorModel(): Settings2EditorModel; // TODO
 
-	openRawDefaultSettings(): Promise<IEditor | null>;
+	openRawDefaultSettings(): Promise<IEditor | undefined>;
 	openSettings(jsonEditor: boolean | undefined, query: string | undefined): Promise<IEditor | undefined>;
 	openGlobalSettings(jsonEditor?: boolean, options?: ISettingsEditorOptions, group?: IEditorGroup): Promise<IEditor | undefined>;
 	openRemoteSettings(): Promise<IEditor | undefined>;
 	openWorkspaceSettings(jsonEditor?: boolean, options?: ISettingsEditorOptions, group?: IEditorGroup): Promise<IEditor | undefined>;
 	openFolderSettings(folder: URI, jsonEditor?: boolean, options?: ISettingsEditorOptions, group?: IEditorGroup): Promise<IEditor | undefined>;
 	switchSettings(target: ConfigurationTarget, resource: URI, jsonEditor?: boolean): Promise<void>;
 	openGlobalKeybindingSettings(textual: boolean): Promise<void>;
-	openDefaultKeybindingsFile(): Promise<IEditor | null>;
+	openDefaultKeybindingsFile(): Promise<IEditor | undefined>;
 
 	configureSettingsForLanguage(language: string | null): void;
 }