Add strong typed definition for Cypress.moment(). (#2746)

cli/package.json

@@ -71,6 +71,7 @@
     "lodash": "4.17.10",
     "log-symbols": "2.2.0",
     "minimist": "1.2.0",
+    "moment": "2.22.2",
     "ramda": "0.24.1",
     "request": "2.87.0",
     "request-progress": "0.3.1",

cli/types/index.d.ts

@@ -10,12 +10,14 @@
 /// <reference path="./blob-util.d.ts" />
 /// <reference path="./bluebird.d.ts" />
 /// <reference path="./minimatch.d.ts" />
+/// <reference path="./moment.d.ts" />
 
 /// <reference types="chai" />
 /// <reference types="chai-jquery" />
 /// <reference types="jquery" />
 /// <reference types="lodash" />
 /// <reference types="mocha" />
+/// <reference types="moment" />
 /// <reference types="sinon" />
 /// <reference types="sinon-chai" />
 
@@ -100,7 +102,7 @@ declare namespace Cypress {
      * @example
      *    const todaysDate = Cypress.moment().format("MMM DD, YYYY")
      */
-    moment: (...args: any[]) => any // perhaps we want to add moment as a dependency for types?
+    moment: Moment.MomentStatic
     /**
      * Cypress automatically includes Bluebird and exposes it as Cypress.Promise.
      *

cli/types/moment.d.ts

@@ -0,0 +1,11 @@
+// Shim definition to export a namespace. Cypress is actually a global module
+// so import/export isn't allowed there. We import here and define a global module
+// so that Cypress can get and use the Moment type
+// tslint:disable-next-line:no-implicit-dependencies
+import * as moment from 'moment'
+export = Moment
+export as namespace Moment
+
+declare namespace Moment {
+  type MomentStatic = typeof moment
+}

cli/types/tests/cypress-tests.ts

@@ -5,6 +5,14 @@ namespace CypressLodashTests {
   })
 }
 
+namespace CypressMomentTests {
+  Cypress.moment() // $ExpectType Moment
+  Cypress.moment('1982-08-23') // $ExpectType Moment
+  Cypress.moment(Date()) // $ExpectType Moment
+  Cypress.moment(Date()).format() // $ExpectType string
+  Cypress.moment().startOf('week') // $ExpectType Moment
+}
+
 namespace CypressJqueryTests {
   Cypress.$ // $ExpectType JQueryStatic
   Cypress.$('selector') // $ExpectType JQuery<HTMLElement>
@@ -22,8 +30,6 @@ namespace CypressConfigTests {
   Cypress.config({ baseUrl: '.', }) // $ExpectType void
 }
 
-Cypress.moment()
-
 namespace CypressEnvTests {
   // Just making sure these are valid - no real type safety
   Cypress.env('foo')