Switch to fast-json-patch (#281)

* Switch to fast-json-patch

* Remove operation cloning

* Use escapePathComponent()

Author: felixfbecker

package.json

@@ -34,14 +34,13 @@
   },
   "dependencies": {
     "@reactivex/rxjs": "^5.3.0",
-    "@types/json-patch": "0.0.29",
     "chai": "^4.0.1",
     "chai-as-promised": "^6.0.0",
     "chalk": "^1.1.3",
     "commander": "^2.9.0",
+    "fast-json-patch": "^1.2.2",
     "glob": "^7.1.1",
     "iterare": "^0.0.8",
-    "json-patch": "^0.6.1",
     "lodash": "^4.17.4",
     "mz": "^2.6.0",
     "object-hash": "^1.1.8",

src/connection.ts

@@ -1,8 +1,7 @@
 import { Observable, Subscription, Symbol } from '@reactivex/rxjs';
 import { EventEmitter } from 'events';
-import { apply, OpPatch } from 'json-patch';
+import jsonpatch from 'fast-json-patch';
 import { camelCase, omit } from 'lodash';
-import { cloneDeep } from 'lodash';
 import { FORMAT_TEXT_MAP, Span, Tracer } from 'opentracing';
 import { inspect } from 'util';
 import { ErrorCodes, Message, StreamMessageReader as VSCodeStreamMessageReader, StreamMessageWriter as VSCodeStreamMessageWriter } from 'vscode-jsonrpc';
@@ -239,7 +238,7 @@ export function registerLanguageHandler(messageEmitter: MessageEmitter, messageW
 			return;
 		}
 		// Call handler method with params and span
-		let observable: Observable<OpPatch>;
+		let observable: Observable<jsonpatch.Operation>;
 		try {
 			// Convert return value to Observable
 			const returnValue = (handler as any)[method](message.params, span);
@@ -270,10 +269,7 @@ export function registerLanguageHandler(messageEmitter: MessageEmitter, messageW
 				})
 				// Build up final result for BC
 				// TODO send null if client declared streaming capability
-				// Clone patches to not modify the values of the patches
-				.map(cloneDeep)
-				.toArray()
-				.map(patches => apply(null, patches))
+				.reduce<jsonpatch.Operation, any>(jsonpatch.applyReducer, null)
 				.finally(() => {
 					// Finish span
 					span.finish();

src/request-type.ts

@@ -1,4 +1,4 @@
-import { OpPatch } from 'json-patch';
+import jsonpatch from 'fast-json-patch';
 import * as vscode from 'vscode-languageserver';
 
 export interface InitializeParams extends vscode.InitializeParams {
@@ -232,5 +232,5 @@ export interface PartialResultParams {
 	 * A JSON Patch that represents updates to the partial result as specified in RFC6902
 	 * https://tools.ietf.org/html/rfc6902
 	 */
-	patch: OpPatch[];
+	patch: jsonpatch.Operation[];
 }

src/test/connection.test.ts

@@ -1,8 +1,8 @@
 
-import { Observable } from '@reactivex/rxjs';
+import { Observable, Subject } from '@reactivex/rxjs';
 import * as assert from 'assert';
 import { EventEmitter } from 'events';
-import { OpPatch } from 'json-patch';
+import jsonpatch from 'fast-json-patch';
 import { Span } from 'opentracing';
 import * as sinon from 'sinon';
 import { PassThrough } from 'stream';
@@ -93,7 +93,7 @@ describe('connection', () => {
 		});
 		it('should call a handler on request and send the result of the returned Observable', async () => {
 			const handler: TypeScriptService = Object.create(TypeScriptService.prototype);
-			const hoverStub = sinon.stub(handler, 'textDocumentHover').returns(Observable.of<OpPatch>(
+			const hoverStub = sinon.stub(handler, 'textDocumentHover').returns(Observable.of<jsonpatch.Operation>(
 				{ op: 'add', path: '', value: [] },
 				{ op: 'add', path: '/-', value: 123 }
 			));
@@ -260,20 +260,19 @@ describe('connection', () => {
 			it('should call a handler on request and send partial results of the returned Observable', async () => {
 				const handler: { [K in keyof TypeScriptService]: TypeScriptService[K] & sinon.SinonStub } = sinon.createStubInstance(TypeScriptService);
 				handler.initialize.returns(Observable.of({ op: 'add', path: '', value: { capabilities: { streaming: true }}}));
-				handler.textDocumentHover.returns(Observable.of<OpPatch>(
-					{ op: 'add', path: '', value: [] },
-					{ op: 'add', path: '/-', value: 123 }
-				));
+
+				const hoverSubject = new Subject();
+				handler.textDocumentHover.returns(hoverSubject);
+
 				const emitter = new EventEmitter();
 				const writer = {
 					write: sinon.spy()
 				};
+
 				registerLanguageHandler(emitter as MessageEmitter, writer as any, handler as any);
-				emitter.emit('message', { jsonrpc: '2.0', id: 1, method: 'initialize', params: { capabilities: { streaming: true }}});
-				emitter.emit('message', { jsonrpc: '2.0', id: 2, method: 'textDocument/hover', params: [1, 2] });
-				sinon.assert.calledOnce(handler.textDocumentHover);
 
-				sinon.assert.callCount(writer.write, 5);
+				// Send initialize
+				emitter.emit('message', { jsonrpc: '2.0', id: 1, method: 'initialize', params: { capabilities: { streaming: true }}});
 				assert.deepEqual(writer.write.args[0], [{
 					jsonrpc: '2.0',
 					method: '$/partialResult',
@@ -287,16 +286,29 @@ describe('connection', () => {
 					id: 1,
 					result: { capabilities: { streaming: true } }
 				}], 'Expected to send final result for initialize');
+
+				// Send hover
+				emitter.emit('message', { jsonrpc: '2.0', id: 2, method: 'textDocument/hover', params: [1, 2] });
+				sinon.assert.calledOnce(handler.textDocumentHover);
+
+				// Simulate initializing JSON Patch Operation
+				hoverSubject.next({ op: 'add', path: '', value: [] });
 				assert.deepEqual(writer.write.args[2], [{
 					jsonrpc: '2.0',
 					method: '$/partialResult',
 					params: { id: 2, patch: [{ op: 'add', path: '', value: [] }] }
 				}], 'Expected to send partial result that initializes array');
+
+				// Simulate streamed value
+				hoverSubject.next({ op: 'add', path: '/-', value: 123 });
 				assert.deepEqual(writer.write.args[3], [{
 					jsonrpc: '2.0',
 					method: '$/partialResult',
 					params: { id: 2, patch: [{ op: 'add', path: '/-', value: 123 }] }
 				}], 'Expected to send partial result that adds 123 to array');
+
+				// Complete Subject to trigger final response
+				hoverSubject.complete();
 				assert.deepEqual(writer.write.args[4], [{
 					jsonrpc: '2.0',
 					id: 2,