import { contextBridge, BrowserWindow, ipcMain } from 'electron' import { expect } from 'chai' import * as fs from 'fs-extra' import * as os from 'os' import * as path from 'path' import { closeWindow } from './window-helpers' import { emittedOnce } from './events-helpers' const fixturesPath = path.resolve(__dirname, 'fixtures', 'api', 'context-bridge') describe('contextBridge', () => { let w: BrowserWindow let dir: string afterEach(async () => { await closeWindow(w) if (dir) await fs.remove(dir) }) it('should not be accessible when contextIsolation is disabled', async () => { w = new BrowserWindow({ show: false, webPreferences: { contextIsolation: false, preload: path.resolve(fixturesPath, 'can-bind-preload.js') } }) const [,bound] = await emittedOnce(ipcMain, 'context-bridge-bound', () => w.loadFile(path.resolve(fixturesPath, 'empty.html'))) expect(bound).to.equal(false) }) it('should be accessible when contextIsolation is enabled', async () => { w = new BrowserWindow({ show: false, webPreferences: { contextIsolation: true, preload: path.resolve(fixturesPath, 'can-bind-preload.js') } }) const [,bound] = await emittedOnce(ipcMain, 'context-bridge-bound', () => w.loadFile(path.resolve(fixturesPath, 'empty.html'))) expect(bound).to.equal(true) }) const generateTests = (useSandbox: boolean) => { describe(`with sandbox=${useSandbox}`, () => { const makeBindingWindow = async (bindingCreator: Function) => { const preloadContent = `const electron_1 = require('electron'); ${useSandbox ? '' : `require('v8').setFlagsFromString('--expose_gc'); const gc=require('vm').runInNewContext('gc'); electron_1.contextBridge.exposeInMainWorld('GCRunner', { run: () => gc() });`} (${bindingCreator.toString()})();` const tmpDir = await fs.mkdtemp(path.resolve(os.tmpdir(), 'electron-spec-preload-')) dir = tmpDir await fs.writeFile(path.resolve(tmpDir, 'preload.js'), preloadContent) w = new BrowserWindow({ show: false, webPreferences: { contextIsolation: true, nodeIntegration: true, sandbox: useSandbox, preload: path.resolve(tmpDir, 'preload.js') } }) await w.loadFile(path.resolve(fixturesPath, 'empty.html')) } const callWithBindings = async (fn: Function) => { return await w.webContents.executeJavaScript(`(${fn.toString()})(window)`) } const getGCInfo = async (): Promise<{ functionCount: number objectCount: number liveFromValues: number liveProxyValues: number }> => { const [,info] = await emittedOnce(ipcMain, 'gc-info', () => w.webContents.send('get-gc-info')) return info } it('should proxy numbers', async () => { await makeBindingWindow(() => { contextBridge.exposeInMainWorld('example', { myNumber: 123, }) }) const result = await callWithBindings((root: any) => { return root.example.myNumber }) expect(result).to.equal(123) }) it('should make properties unwriteable', async () => { await makeBindingWindow(() => { contextBridge.exposeInMainWorld('example', { myNumber: 123, }) }) const result = await callWithBindings((root: any) => { root.example.myNumber = 456 return root.example.myNumber }) expect(result).to.equal(123) }) it('should proxy strings', async () => { await makeBindingWindow(() => { contextBridge.exposeInMainWorld('example', { myString: 'my-words', }) }) const result = await callWithBindings((root: any) => { return root.example.myString }) expect(result).to.equal('my-words') }) it('should proxy arrays', async () => { await makeBindingWindow(() => { contextBridge.exposeInMainWorld('example', { myArr: [123, 'my-words'], }) }) const result = await callWithBindings((root: any) => { return root.example.myArr }) expect(result).to.deep.equal([123, 'my-words']) }) it('should make arrays immutable', async () => { await makeBindingWindow(() => { contextBridge.exposeInMainWorld('example', { myArr: [123, 'my-words'], }) }) const immutable = await callWithBindings((root: any) => { try { root.example.myArr.push(456) return false } catch { return true } }) expect(immutable).to.equal(true) }) it('should proxy booleans', async () => { await makeBindingWindow(() => { contextBridge.exposeInMainWorld('example', { myBool: true, }) }) const result = await callWithBindings((root: any) => { return root.example.myBool }) expect(result).to.equal(true) }) it('should proxy promises and resolve with the correct value', async () => { await makeBindingWindow(() => { contextBridge.exposeInMainWorld('example', { myPromise: Promise.resolve('i-resolved'), }) }) const result = await callWithBindings(async (root: any) => { return await root.example.myPromise }) expect(result).to.equal('i-resolved') }) it('should proxy promises and reject with the correct value', async () => { await makeBindingWindow(() => { contextBridge.exposeInMainWorld('example', { myPromise: Promise.reject('i-rejected'), }) }) const result = await callWithBindings(async (root: any) => { try { await root.example.myPromise return null } catch (err) { return err } }) expect(result).to.equal('i-rejected') }) it('should proxy promises and resolve with the correct value if it resolves later', async () => { await makeBindingWindow(() => { contextBridge.exposeInMainWorld('example', { myPromise: () => new Promise(r => setTimeout(() => r('delayed'), 20)), }) }) const result = await callWithBindings(async (root: any) => { return await root.example.myPromise() }) expect(result).to.equal('delayed') }) it('should proxy nested promises correctly', async () => { await makeBindingWindow(() => { contextBridge.exposeInMainWorld('example', { myPromise: () => new Promise(r => setTimeout(() => r(Promise.resolve(123)), 20)), }) }) const result = await callWithBindings(async (root: any) => { return await root.example.myPromise() }) expect(result).to.equal(123) }) it('should proxy methods', async () => { await makeBindingWindow(() => { contextBridge.exposeInMainWorld('example', { getNumber: () => 123, getString: () => 'help', getBoolean: () => false, getPromise: async () => 'promise' }) }) const result = await callWithBindings(async (root: any) => { return [root.example.getNumber(), root.example.getString(), root.example.getBoolean(), await root.example.getPromise()] }) expect(result).to.deep.equal([123, 'help', false, 'promise']) }) it('should proxy methods that are callable multiple times', async () => { await makeBindingWindow(() => { contextBridge.exposeInMainWorld('example', { doThing: () => 123 }) }) const result = await callWithBindings(async (root: any) => { return [root.example.doThing(), root.example.doThing(), root.example.doThing()] }) expect(result).to.deep.equal([123, 123, 123]) }) it('should proxy methods in the reverse direction', async () => { await makeBindingWindow(() => { contextBridge.exposeInMainWorld('example', { callWithNumber: (fn: any) => fn(123), }) }) const result = await callWithBindings(async (root: any) => { return root.example.callWithNumber((n: number) => n + 1) }) expect(result).to.equal(124) }) it('should proxy promises in the reverse direction', async () => { await makeBindingWindow(() => { contextBridge.exposeInMainWorld('example', { getPromiseValue: async (p: Promise) => await p, }) }) const result = await callWithBindings(async (root: any) => { return await root.example.getPromiseValue(Promise.resolve('my-proxied-value')) }) expect(result).to.equal('my-proxied-value') }) it('should proxy objects with number keys', async () => { await makeBindingWindow(() => { contextBridge.exposeInMainWorld('example', { [1]: 123, [2]: 456, '3': 789 }) }) const result = await callWithBindings(async (root: any) => { return [root.example[1], root.example[2], root.example[3], Array.isArray(root.example)] }) expect(result).to.deep.equal([123, 456, 789, false]) }) it('it should proxy null and undefined correctly', async () => { await makeBindingWindow(() => { contextBridge.exposeInMainWorld('example', { values: [null, undefined] }) }) const result = await callWithBindings((root: any) => { // Convert to strings as although the context bridge keeps the right value // IPC does not return root.example.values.map((val: any) => `${val}`) }) expect(result).to.deep.equal(['null', 'undefined']) }) it('should proxy typed arrays and regexps through the serializer', async () => { await makeBindingWindow(() => { contextBridge.exposeInMainWorld('example', { arr: new Uint8Array(100), regexp: /a/g }) }) const result = await callWithBindings((root: any) => { return [root.example.arr.__proto__ === Uint8Array.prototype, root.example.regexp.__proto__ === RegExp.prototype] }) expect(result).to.deep.equal([true, true]) }) it('it should handle recursive objects', async () => { await makeBindingWindow(() => { const o: any = { value: 135 } o.o = o contextBridge.exposeInMainWorld('example', { o, }) }) const result = await callWithBindings((root: any) => { return [root.example.o.value, root.example.o.o.value, root.example.o.o.o.value] }) expect(result).to.deep.equal([135, 135, 135]) }) it('it should follow expected simple rules of object identity', async () => { await makeBindingWindow(() => { const o: any = { value: 135 } const sub = { thing: 7 } o.a = sub o.b = sub contextBridge.exposeInMainWorld('example', { o, }) }) const result = await callWithBindings((root: any) => { return root.example.a === root.example.b }) expect(result).to.equal(true) }) it('it should follow expected complex rules of object identity', async () => { await makeBindingWindow(() => { let first: any = null contextBridge.exposeInMainWorld('example', { check: (arg: any) => { if (first === null) { first = arg } else { return first === arg } }, }) }) const result = await callWithBindings((root: any) => { const o = { thing: 123 } root.example.check(o) return root.example.check(o) }) expect(result).to.equal(true) }) // Can only run tests which use the GCRunner in non-sandboxed environments if (!useSandbox) { it('should release the global hold on methods sent across contexts', async () => { await makeBindingWindow(() => { require('electron').ipcRenderer.on('get-gc-info', e => e.sender.send('gc-info', (contextBridge as any).debugGC())) contextBridge.exposeInMainWorld('example', { getFunction: () => () => 123 }) }) expect((await getGCInfo()).functionCount).to.equal(2) await callWithBindings(async (root: any) => { root.x = [root.example.getFunction()] }) expect((await getGCInfo()).functionCount).to.equal(3) await callWithBindings(async (root: any) => { root.x = [] root.GCRunner.run() }) expect((await getGCInfo()).functionCount).to.equal(2) }) it('should release the global hold on objects sent across contexts when the object proxy is de-reffed', async () => { await makeBindingWindow(() => { require('electron').ipcRenderer.on('get-gc-info', e => e.sender.send('gc-info', (contextBridge as any).debugGC())) let myObj: any contextBridge.exposeInMainWorld('example', { setObj: (o: any) => { myObj = o }, getObj: () => myObj }) }) await callWithBindings(async (root: any) => { root.GCRunner.run() }) // Initial Setup let info = await getGCInfo() expect(info.liveFromValues).to.equal(3) expect(info.liveProxyValues).to.equal(3) expect(info.objectCount).to.equal(6) // Create Reference await callWithBindings(async (root: any) => { root.x = { value: 123 } root.example.setObj(root.x) root.GCRunner.run() }) info = await getGCInfo() expect(info.liveFromValues).to.equal(4) expect(info.liveProxyValues).to.equal(4) expect(info.objectCount).to.equal(8) // Release Reference await callWithBindings(async (root: any) => { root.example.setObj(null) root.GCRunner.run() }) info = await getGCInfo() expect(info.liveFromValues).to.equal(3) expect(info.liveProxyValues).to.equal(3) expect(info.objectCount).to.equal(6) }) it('should release the global hold on objects sent across contexts when the object source is de-reffed', async () => { await makeBindingWindow(() => { require('electron').ipcRenderer.on('get-gc-info', e => e.sender.send('gc-info', (contextBridge as any).debugGC())) let myObj: any; contextBridge.exposeInMainWorld('example', { setObj: (o: any) => { myObj = o }, getObj: () => myObj }) }) await callWithBindings(async (root: any) => { root.GCRunner.run() }) // Initial Setup let info = await getGCInfo() expect(info.liveFromValues).to.equal(3) expect(info.liveProxyValues).to.equal(3) expect(info.objectCount).to.equal(6) // Create Reference await callWithBindings(async (root: any) => { root.x = { value: 123 } root.example.setObj(root.x) root.GCRunner.run() }) info = await getGCInfo() expect(info.liveFromValues).to.equal(4) expect(info.liveProxyValues).to.equal(4) expect(info.objectCount).to.equal(8) // Release Reference await callWithBindings(async (root: any) => { delete root.x root.GCRunner.run() }) info = await getGCInfo() expect(info.liveFromValues).to.equal(3) expect(info.liveProxyValues).to.equal(3) expect(info.objectCount).to.equal(6) }) it('should not crash when the object source is de-reffed AND the object proxy is de-reffed', async () => { await makeBindingWindow(() => { require('electron').ipcRenderer.on('get-gc-info', e => e.sender.send('gc-info', (contextBridge as any).debugGC())) let myObj: any; contextBridge.exposeInMainWorld('example', { setObj: (o: any) => { myObj = o }, getObj: () => myObj }) }) await callWithBindings(async (root: any) => { root.GCRunner.run() }) // Initial Setup let info = await getGCInfo() expect(info.liveFromValues).to.equal(3) expect(info.liveProxyValues).to.equal(3) expect(info.objectCount).to.equal(6) // Create Reference await callWithBindings(async (root: any) => { root.x = { value: 123 } root.example.setObj(root.x) root.GCRunner.run() }) info = await getGCInfo() expect(info.liveFromValues).to.equal(4) expect(info.liveProxyValues).to.equal(4) expect(info.objectCount).to.equal(8) // Release Reference await callWithBindings(async (root: any) => { delete root.x root.example.setObj(null) root.GCRunner.run() }) info = await getGCInfo() expect(info.liveFromValues).to.equal(3) expect(info.liveProxyValues).to.equal(3) expect(info.objectCount).to.equal(6) }) } it('it should not let you overwrite existing exposed things', async () => { await makeBindingWindow(() => { let threw = false contextBridge.exposeInMainWorld('example', { attempt: 1, getThrew: () => threw }) try { contextBridge.exposeInMainWorld('example', { attempt: 2, getThrew: () => threw }) } catch { threw = true } }) const result = await callWithBindings((root: any) => { return [root.example.attempt, root.example.getThrew()] }) expect(result).to.deep.equal([1, true]) }) it('should work with complex nested methods and promises', async () => { await makeBindingWindow(() => { contextBridge.exposeInMainWorld('example', { first: (second: Function) => second(async (fourth: Function) => { return await fourth() }) }) }) const result = await callWithBindings((root: any) => { return root.example.first((third: Function) => { return third(() => Promise.resolve('final value')) }) }) expect(result).to.equal('final value') }) it('should throw an error when recursion depth is exceeded', async () => { await makeBindingWindow(() => { contextBridge.exposeInMainWorld('example', { doThing: (a: any) => console.log(a) }) }) let threw = await callWithBindings((root: any) => { try { let a: any = [] for (let i = 0; i < 999; i++) { a = [ a ] } root.example.doThing(a) return false } catch { return true } }) expect(threw).to.equal(false) threw = await callWithBindings((root: any) => { try { let a: any = [] for (let i = 0; i < 1000; i++) { a = [ a ] } root.example.doThing(a) return false } catch { return true } }) expect(threw).to.equal(true) }) it('should not leak prototypes', async () => { await makeBindingWindow(() => { contextBridge.exposeInMainWorld('example', { number: 123, string: 'string', boolean: true, arr: [123, 'string', true, ['foo']], getNumber: () => 123, getString: () => 'string', getBoolean: () => true, getArr: () => [123, 'string', true, ['foo']], getPromise: async () => ({ number: 123, string: 'string', boolean: true, fn: () => 'string', arr: [123, 'string', true, ['foo']]}), getFunctionFromFunction: async () => () => null, object: { number: 123, string: 'string', boolean: true, arr: [123, 'string', true, ['foo']], getPromise: async () => ({ number: 123, string: 'string', boolean: true, fn: () => 'string', arr: [123, 'string', true, ['foo']]}), }, receiveArguments: (fn: any) => fn({ key: 'value' }) }) }) const result = await callWithBindings(async (root: any) => { const { example } = root let arg: any example.receiveArguments((o: any) => { arg = o }) const protoChecks = [ [example, Object], [example.number, Number], [example.string, String], [example.boolean, Boolean], [example.arr, Array], [example.arr[0], Number], [example.arr[1], String], [example.arr[2], Boolean], [example.arr[3], Array], [example.arr[3][0], String], [example.getNumber, Function], [example.getNumber(), Number], [example.getString(), String], [example.getBoolean(), Boolean], [example.getArr(), Array], [example.getArr()[0], Number], [example.getArr()[1], String], [example.getArr()[2], Boolean], [example.getArr()[3], Array], [example.getArr()[3][0], String], [example.getFunctionFromFunction, Function], [example.getFunctionFromFunction(), Promise], [await example.getFunctionFromFunction(), Function], [example.getPromise(), Promise], [await example.getPromise(), Object], [(await example.getPromise()).number, Number], [(await example.getPromise()).string, String], [(await example.getPromise()).boolean, Boolean], [(await example.getPromise()).fn, Function], [(await example.getPromise()).fn(), String], [(await example.getPromise()).arr, Array], [(await example.getPromise()).arr[0], Number], [(await example.getPromise()).arr[1], String], [(await example.getPromise()).arr[2], Boolean], [(await example.getPromise()).arr[3], Array], [(await example.getPromise()).arr[3][0], String], [example.object, Object], [example.object.number, Number], [example.object.string, String], [example.object.boolean, Boolean], [example.object.arr, Array], [example.object.arr[0], Number], [example.object.arr[1], String], [example.object.arr[2], Boolean], [example.object.arr[3], Array], [example.object.arr[3][0], String], [await example.object.getPromise(), Object], [(await example.object.getPromise()).number, Number], [(await example.object.getPromise()).string, String], [(await example.object.getPromise()).boolean, Boolean], [(await example.object.getPromise()).fn, Function], [(await example.object.getPromise()).fn(), String], [(await example.object.getPromise()).arr, Array], [(await example.object.getPromise()).arr[0], Number], [(await example.object.getPromise()).arr[1], String], [(await example.object.getPromise()).arr[2], Boolean], [(await example.object.getPromise()).arr[3], Array], [(await example.object.getPromise()).arr[3][0], String], [arg, Object], [arg.key, String] ] return { protoMatches: protoChecks.map(([a, Constructor]) => a.__proto__ === Constructor.prototype) } }) // Every protomatch should be true expect(result.protoMatches).to.deep.equal(result.protoMatches.map(() => true)) }) }) } generateTests(true) generateTests(false) })