Remove external object-is dependency

Author: kitten

package.json

@@ -35,11 +35,6 @@
       "@babel/preset-react"
     ]
   },
-  "jest": {
-    "globals": {
-      "__DEV__": true
-    }
-  },
   "lint-staged": {
     "**/*.js": [
       "flow focus-check",
@@ -58,9 +53,7 @@
     "react": "^16.8.0",
     "react-is": "^16.8.0"
   },
-  "dependencies": {
-    "object-is": "^1.1.2"
-  },
+  "dependencies": {},
   "devDependencies": {
     "@ampproject/rollup-plugin-closure-compiler": "^0.25.2",
     "@babel/core": "^7.9.0",

src/internals/dispatcher.js

@@ -1,8 +1,8 @@
 // @flow
 // Source: https://github.com/facebook/react/blob/c21c41e/packages/react-dom/src/server/ReactPartialRendererHooks.js
 
-import is from 'object-is'
 import { readContextValue } from './context'
+import is from './objectIs'
 
 import type {
   AbstractContext,
@@ -159,7 +159,7 @@ function useState<S>(
 function useReducer<S, I, A>(
   reducer: (S, A) => S,
   initialArg: I,
-  init?: I => S
+  init?: (I) => S
 ): [S, Dispatch<A>] {
   const id = getCurrentIdentity()
   workInProgressHook = createWorkInProgressHook()
@@ -287,7 +287,7 @@ function useCallback<T>(callback: T, deps: Array<mixed> | void | null): T {
 function noop(): void {}
 
 function useTransition(): [(callback: () => void) => void, boolean] {
-  const startTransition = callback => {
+  const startTransition = (callback) => {
     callback()
   }
   return [startTransition, false]

src/internals/objectIs.js

@@ -0,0 +1,23 @@
+/**
+ * Copyright (c) Facebook, Inc. and its affiliates.
+ *
+ * This source code is licensed under the MIT license found in the
+ * LICENSE file in the root directory of this source tree.
+ *
+ * @flow
+ */
+
+/**
+ * inlined Object.is polyfill to avoid requiring consumers ship their own
+ * https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Object/is
+ */
+function is(x: any, y: any) {
+  return (
+    (x === y && (x !== 0 || 1 / x === 1 / y)) || (x !== x && y !== y) // eslint-disable-line no-self-compare
+  )
+}
+
+const objectIs: (x: any, y: any) => boolean =
+  typeof Object.is === 'function' ? Object.is : is
+
+export default objectIs

types/globals.js

@@ -3901,14 +3901,6 @@ object-inspect@^1.7.0:
   resolved "https://registry.yarnpkg.com/object-inspect/-/object-inspect-1.7.0.tgz#f4f6bd181ad77f006b5ece60bd0b6f398ff74a67"
   integrity sha512-a7pEHdh1xKIAgTySUGgLMx/xwDZskN1Ud6egYYN3EdRW4ZMPNEDUTF+hwy2LUC+Bl+SyLXANnwz/jyh/qutKUw==
 
-object-is@^1.1.2:
-  version "1.1.2"
-  resolved "https://registry.yarnpkg.com/object-is/-/object-is-1.1.2.tgz#c5d2e87ff9e119f78b7a088441519e2eec1573b6"
-  integrity sha512-5lHCz+0uufF6wZ7CRFWJN3hp8Jqblpgve06U5CMQ3f//6iDjPr2PEo9MWCjEssDsa+UZEL4PkFpr+BMop6aKzQ==
-  dependencies:
-    define-properties "^1.1.3"
-    es-abstract "^1.17.5"
-
 object-keys@^1.0.11, object-keys@^1.0.12, object-keys@^1.1.1:
   version "1.1.1"
   resolved "https://registry.yarnpkg.com/object-keys/-/object-keys-1.1.1.tgz#1c47f272df277f3b1daf061677d9c82e2322c60e"