wire ext host save participant to main thread save participant

src/vs/workbench/api/node/mainThreadSaveParticipant.ts

@@ -0,0 +1,122 @@
+/*---------------------------------------------------------------------------------------------
+ *  Copyright (c) Microsoft Corporation. All rights reserved.
+ *  Licensed under the MIT License. See License.txt in the project root for license information.
+ *--------------------------------------------------------------------------------------------*/
+
+'use strict';
+
+import {IDisposable, dispose} from 'vs/base/common/lifecycle';
+import {TPromise} from 'vs/base/common/winjs.base';
+import {ICodeEditorService} from 'vs/editor/common/services/codeEditorService';
+import {IThreadService} from 'vs/workbench/services/thread/common/threadService';
+import {ISaveParticipant, ITextFileEditorModel} from 'vs/workbench/parts/files/common/files';
+import {IFilesConfiguration} from 'vs/platform/files/common/files';
+import {IPosition, IModel} from 'vs/editor/common/editorCommon';
+import {Selection} from 'vs/editor/common/core/selection';
+import {trimTrailingWhitespace} from 'vs/editor/common/commands/trimTrailingWhitespaceCommand';
+import {IConfigurationService} from 'vs/platform/configuration/common/configuration';
+import {TextFileEditorModel} from 'vs/workbench/parts/files/common/editors/textFileEditorModel';
+import {ExtHostContext, ExtHostDocumentSaveParticipantShape} from './extHost.protocol';
+
+// TODO@joh move this to the extension host
+class TrimWhitespaceParticipant {
+
+	private trimTrailingWhitespace: boolean = false;
+	private toUnbind: IDisposable[] = [];
+
+	constructor(
+		@IConfigurationService private configurationService: IConfigurationService,
+		@ICodeEditorService private codeEditorService: ICodeEditorService
+	) {
+		this.registerListeners();
+		this.onConfigurationChange(this.configurationService.getConfiguration<IFilesConfiguration>());
+	}
+
+	public dispose(): void {
+		this.toUnbind = dispose(this.toUnbind);
+	}
+
+	private registerListeners(): void {
+		this.toUnbind.push(this.configurationService.onDidUpdateConfiguration(e => this.onConfigurationChange(e.config)));
+	}
+
+	private onConfigurationChange(configuration: IFilesConfiguration): void {
+		this.trimTrailingWhitespace = configuration && configuration.files && configuration.files.trimTrailingWhitespace;
+	}
+
+	public participate(model: ITextFileEditorModel, env: { isAutoSaved: boolean }): any {
+		if (this.trimTrailingWhitespace) {
+			this.doTrimTrailingWhitespace(model.textEditorModel, env.isAutoSaved);
+		}
+	}
+
+	private doTrimTrailingWhitespace(model: IModel, isAutoSaved: boolean): void {
+		let prevSelection: Selection[] = [new Selection(1, 1, 1, 1)];
+		const cursors: IPosition[] = [];
+
+		// Find `prevSelection` in any case do ensure a good undo stack when pushing the edit
+		// Collect active cursors in `cursors` only if `isAutoSaved` to avoid having the cursors jump
+		if (model.isAttachedToEditor()) {
+			const allEditors = this.codeEditorService.listCodeEditors();
+			for (let i = 0, len = allEditors.length; i < len; i++) {
+				const editor = allEditors[i];
+				const editorModel = editor.getModel();
+
+				if (!editorModel) {
+					continue; // empty editor
+				}
+
+				if (model === editorModel) {
+					prevSelection = editor.getSelections();
+					if (isAutoSaved) {
+						cursors.push(...prevSelection.map(s => {
+							return {
+								lineNumber: s.positionLineNumber,
+								column: s.positionColumn
+							};
+						}));
+					}
+				}
+			}
+		}
+
+		const ops = trimTrailingWhitespace(model, cursors);
+		if (!ops.length) {
+			return; // Nothing to do
+		}
+
+		model.pushEditOperations(prevSelection, ops, (edits) => prevSelection);
+	}
+}
+
+// The save participant can change a model before its saved to support various scenarios like trimming trailing whitespace
+export class SaveParticipant implements ISaveParticipant {
+
+	private _mainThreadSaveParticipant: TrimWhitespaceParticipant;
+	private _extHostSaveParticipant: ExtHostDocumentSaveParticipantShape;
+
+	constructor(
+		@IConfigurationService configurationService: IConfigurationService,
+		@ICodeEditorService codeEditorService: ICodeEditorService,
+		@IThreadService threadService: IThreadService
+	) {
+		this._mainThreadSaveParticipant = new TrimWhitespaceParticipant(configurationService, codeEditorService);
+		this._extHostSaveParticipant = threadService.get(ExtHostContext.ExtHostDocumentSaveParticipant);
+
+		// Hook into model
+		TextFileEditorModel.setSaveParticipant(this);
+	}
+
+	dispose() {
+		this._mainThreadSaveParticipant.dispose();
+	}
+
+	participate(model: ITextFileEditorModel, env: { isAutoSaved: boolean }): TPromise<any> {
+		try {
+			this._mainThreadSaveParticipant.participate(model, env);
+		} catch (err) {
+			// ignore
+		}
+		return this._extHostSaveParticipant.$participateInSave(model.getResource());
+	}
+}