refactor: transform test/utils to ts (#1785)

Author: myNameIsDu

test/utils/Subscription.spec.js renamed to test/utils/Subscription.spec.ts

@@ -1,20 +1,22 @@
 import { createSubscription } from '../../src/utils/Subscription'
+import type { Subscription } from '../../src/utils/Subscription'
+import type { Store } from 'redux'
 
 describe('Subscription', () => {
-  let notifications
-  let store
-  let parent
+  let notifications: string[]
+  let store: Store
+  let parent: Subscription
 
   beforeEach(() => {
     notifications = []
-    store = { subscribe: () => jest.fn() }
+    store = { subscribe: () => jest.fn() } as unknown as Store
 
     parent = createSubscription(store)
     parent.onStateChange = () => {}
     parent.trySubscribe()
   })
 
-  function subscribeChild(name) {
+  function subscribeChild(name: string) {
     const child = createSubscription(store, parent)
     child.onStateChange = () => notifications.push(name)
     child.trySubscribe()

test/utils/isPlainObject.spec.js renamed to test/utils/isPlainObject.spec.ts

@@ -1,12 +1,8 @@
 import isPlainObject from '../../src/utils/isPlainObject'
 import vm from 'vm'
-
+class Test {}
 describe('isPlainObject', () => {
   it('returns true only if plain object', () => {
-    function Test() {
-      this.prop = 1
-    }
-
     const sandbox = { fromAnotherRealm: false }
     vm.runInNewContext('fromAnotherRealm = {}', sandbox)
 
@@ -15,6 +11,7 @@ describe('isPlainObject', () => {
     expect(isPlainObject(new Date())).toBe(false)
     expect(isPlainObject([1, 2, 3])).toBe(false)
     expect(isPlainObject(null)).toBe(false)
+    //@ts-expect-error
     expect(isPlainObject()).toBe(false)
     expect(isPlainObject({ x: 1, y: 2 })).toBe(true)
     expect(isPlainObject(Object.create(null))).toBe(true)