Implement onWillSaveTextDocument plugin api event handler.

packages/monaco/src/browser/monaco-editor-model.ts

@@ -39,6 +39,7 @@ export class MonacoEditorModel implements ITextEditorModel, TextEditorDocument {
 
     autoSave: 'on' | 'off' = 'on';
     autoSaveDelay: number = 500;
+    readonly onWillSaveLoopTimeOut = 1500;
 
     protected model: monaco.editor.IModel;
     protected readonly resolveModel: Promise<void>;
@@ -344,7 +345,7 @@ export class MonacoEditorModel implements ITextEditorModel, TextEditorDocument {
         const timeoutPromise = new Promise((resolve, reject) => timeoutHandle = <any>setTimeout(() => {
             didTimeout = true;
             reject(new Error('onWillSave listener loop timeout'));
-        }, 1000));
+        }, this.onWillSaveLoopTimeOut));
 
         const firing = this.onWillSaveModelEmitter.sequence(async listener => {
             if (shouldStop()) {

packages/plugin-ext/src/api/plugin-api.ts

@@ -698,6 +698,7 @@ export interface ModelChangedEvent {
 export interface DocumentsExt {
     $acceptModelModeChanged(startUrl: UriComponents, oldModeId: string, newModeId: string): void;
     $acceptModelSaved(strUrl: UriComponents): void;
+    $acceptModelWillSave(strUrl: UriComponents, reason: theia.TextDocumentSaveReason): Promise<SingleEditOperation[]>;
     $acceptDirtyStateChanged(strUrl: UriComponents, isDirty: boolean): void;
     $acceptModelChanged(strUrl: UriComponents, e: ModelChangedEvent, isDirty: boolean): void;
 }

packages/plugin-ext/src/main/browser/documents-main.ts

@@ -42,7 +42,7 @@ export class DocumentsMainImpl implements DocumentsMain {
         modelService: EditorModelService,
         rpc: RPCProtocol,
         private editorManger: EditorManager,
-        private openerService: OpenerService
+        private openerService: OpenerService,
     ) {
         this.proxy = rpc.getProxy(MAIN_RPC_CONTEXT.DOCUMENTS_EXT);
 
@@ -53,6 +53,18 @@ export class DocumentsMainImpl implements DocumentsMain {
         this.toDispose.push(modelService.onModelSaved(m => {
             this.proxy.$acceptModelSaved(m.textEditorModel.uri);
         }));
+        this.toDispose.push(modelService.onModelWillSave(onWillSaveModelEvent => {
+            onWillSaveModelEvent.waitUntil(new Promise<monaco.editor.IIdentifiedSingleEditOperation[]>(async resolve => {
+                const edits = await this.proxy.$acceptModelWillSave(onWillSaveModelEvent.model.textEditorModel.uri, onWillSaveModelEvent.reason);
+                const transformedEdits = edits.map((edit): monaco.editor.IIdentifiedSingleEditOperation =>
+                ({
+                    range: monaco.Range.lift(edit.range),
+                    text: edit.text!,
+                    forceMoveMarkers: edit.forceMoveMarkers
+                }));
+                resolve(transformedEdits);
+            }));
+        }));
         this.toDispose.push(modelService.onModelDirtyChanged(m => {
             this.proxy.$acceptDirtyStateChanged(m.textEditorModel.uri, m.dirty);
         }));

packages/plugin-ext/src/main/browser/text-editor-model-service.ts

@@ -14,7 +14,7 @@
  * SPDX-License-Identifier: EPL-2.0 OR GPL-2.0 WITH Classpath-exception-2.0
  ********************************************************************************/
 import { Event, Emitter } from '@theia/core';
-import { MonacoEditorModel } from '@theia/monaco/lib/browser/monaco-editor-model';
+import { MonacoEditorModel, WillSaveMonacoModelEvent } from '@theia/monaco/lib/browser/monaco-editor-model';
 import { injectable, inject } from 'inversify';
 import { MonacoTextModelService } from '@theia/monaco/lib/browser/monaco-text-model-service';
 import { MonacoWorkspace } from '@theia/monaco/lib/browser/monaco-workspace';
@@ -25,6 +25,7 @@ export interface EditorModelService {
     onModelRemoved: Event<MonacoEditorModel>;
     onModelModeChanged: Event<{ model: MonacoEditorModel, oldModeId: string }>;
 
+    onModelWillSave: Event<WillSaveMonacoModelEvent>;
     onModelDirtyChanged: Event<MonacoEditorModel>;
     onModelSaved: Event<MonacoEditorModel>;
 
@@ -39,11 +40,13 @@ export class EditorModelServiceImpl implements EditorModelService {
     private onModelRemovedEmitter = new Emitter<MonacoEditorModel>();
     private modelDirtyEmitter = new Emitter<MonacoEditorModel>();
     private modelSavedEmitter = new Emitter<MonacoEditorModel>();
+    private onModelWillSavedEmitter = new Emitter<WillSaveMonacoModelEvent>();
 
     onModelDirtyChanged: Event<MonacoEditorModel> = this.modelDirtyEmitter.event;
     onModelSaved: Event<MonacoEditorModel> = this.modelSavedEmitter.event;
     onModelModeChanged = this.modelModeChangedEmitter.event;
     onModelRemoved = this.onModelRemovedEmitter.event;
+    onModelWillSave = this.onModelWillSavedEmitter.event;
 
     constructor(@inject(MonacoTextModelService) monacoModelService: MonacoTextModelService,
         @inject(MonacoWorkspace) monacoWorkspace: MonacoWorkspace) {
@@ -70,6 +73,9 @@ export class EditorModelServiceImpl implements EditorModelService {
         model.onDirtyChanged(_ => {
             this.modelDirtyEmitter.fire(model);
         });
+        model.onWillSaveModel(willSaveModelEvent => {
+            this.onModelWillSavedEmitter.fire(willSaveModelEvent);
+        });
     }
 
     get onModelAdded(): Event<MonacoEditorModel> {

packages/plugin-ext/src/plugin/documents.ts

@@ -13,7 +13,7 @@
  *
  * SPDX-License-Identifier: EPL-2.0 OR GPL-2.0 WITH Classpath-exception-2.0
  ********************************************************************************/
-import { DocumentsExt, ModelChangedEvent, PLUGIN_RPC_CONTEXT, DocumentsMain } from '../api/plugin-api';
+import { DocumentsExt, ModelChangedEvent, PLUGIN_RPC_CONTEXT, DocumentsMain, SingleEditOperation } from '../api/plugin-api';
 import URI from 'vscode-uri';
 import { UriComponents } from '../common/uri-components';
 import { RPCProtocol } from '../api/rpc-protocol';
@@ -24,18 +24,21 @@ import { EditorsAndDocumentsExtImpl } from './editors-and-documents';
 import * as Converter from './type-converters';
 import { DisposableCollection } from '@theia/core/lib/common/disposable';
 import { Range, TextDocumentShowOptions } from '../api/model';
+import { TextEdit } from './types-impl';
 
 export class DocumentsExtImpl implements DocumentsExt {
     private toDispose = new DisposableCollection();
     private _onDidAddDocument = new Emitter<theia.TextDocument>();
     private _onDidRemoveDocument = new Emitter<theia.TextDocument>();
     private _onDidChangeDocument = new Emitter<theia.TextDocumentChangeEvent>();
     private _onDidSaveTextDocument = new Emitter<theia.TextDocument>();
+    private _onWillSaveTextDocument = new Emitter<theia.TextDocumentWillSaveEvent>();
 
     readonly onDidAddDocument: Event<theia.TextDocument> = this._onDidAddDocument.event;
     readonly onDidRemoveDocument: Event<theia.TextDocument> = this._onDidRemoveDocument.event;
     readonly onDidChangeDocument: Event<theia.TextDocumentChangeEvent> = this._onDidChangeDocument.event;
     readonly onDidSaveTextDocument: Event<theia.TextDocument> = this._onDidSaveTextDocument.event;
+    readonly onWillSaveTextDocument: Event<theia.TextDocumentWillSaveEvent> = this._onWillSaveTextDocument.event;
 
     private proxy: DocumentsMain;
     private loadingDocuments = new Map<string, Promise<DocumentDataExt | undefined>>();
@@ -78,6 +81,35 @@ export class DocumentsExtImpl implements DocumentsExt {
             this._onDidSaveTextDocument.fire(data.document);
         }
     }
+    $acceptModelWillSave(strUrl: UriComponents, reason: theia.TextDocumentSaveReason): Promise<SingleEditOperation[]> {
+        return new Promise<SingleEditOperation[]>((resolve, reject) => {
+            const uri = URI.revive(strUrl);
+            const uriString = uri.toString();
+            const data = this.editorsAndDocuments.getDocument(uriString);
+            if (data) {
+                const onWillSaveEvent: theia.TextDocumentWillSaveEvent = {
+                    document: data.document,
+                    reason: reason,
+                    /* tslint:disable:no-any */
+                    waitUntil: async (editsPromise: PromiseLike<theia.TextEdit[] | any>) => {
+                        const editsObjs = await editsPromise;
+                        if (this.isTextEditArray(editsObjs)) {
+                            const editOperations: SingleEditOperation[] = (editsObjs as theia.TextEdit[]).map(textEdit => Converter.fromTextEdit(textEdit));
+                            resolve(editOperations);
+                        } else {
+                            resolve([]);
+                        }
+                    }
+                };
+                this._onWillSaveTextDocument.fire(onWillSaveEvent);
+            }
+        });
+    }
+
+    isTextEditArray(obj: any): obj is theia.TextEdit[] {
+        return Array.isArray(obj) && obj.every((elem: any) => TextEdit.isTextEdit(elem));
+    }
+
     $acceptDirtyStateChanged(strUrl: UriComponents, isDirty: boolean): void {
         const uri = URI.revive(strUrl);
         const uriString = uri.toString();

packages/plugin-ext/src/plugin/plugin-context.ts

@@ -379,8 +379,7 @@ export function createAPIFactory(
                 return documents.onDidAddDocument(listener, thisArg, disposables);
             },
             onWillSaveTextDocument(listener, thisArg?, disposables?) {
-                // TODO to implement
-                return { dispose: () => { } };
+                return documents.onWillSaveTextDocument(listener, thisArg, disposables);
             },
             onDidSaveTextDocument(listener, thisArg?, disposables?) {
                 return documents.onDidSaveTextDocument(listener, thisArg, disposables);

packages/plugin-ext/src/plugin/types-impl.ts

@@ -666,7 +666,7 @@ export class TextEdit {
         if (!thing) {
             return false;
         }
-        return Range.isRange((<TextEdit>thing))
+        return Range.isRange((<TextEdit>thing).range)
             && typeof (<TextEdit>thing).newText === 'string';
     }