initial commit: basic flow errors

lib/utils/index.js

@@ -1,3 +1,6 @@
+/**
+ * @flow
+ */
 // modeled after base64 web-safe chars, but ordered by ASCII
 const PUSH_CHARS = '-0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZ_abcdefghijklmnopqrstuvwxyz';
 const hasOwnProperty = Object.hasOwnProperty;
@@ -8,7 +11,8 @@ const _handler = (resolve, reject, errorPrefix, err, resp) => {
   // resolve / reject after events etc
   setImmediate(() => {
     if (err) {
-      const firebaseError = new Error(err.message);
+      // $FlowFixMe
+      const firebaseError: FirebaseError = new Error(err.message);
 
       if (isObject(err)) {
         Object.keys(err).forEach(key => Object.defineProperty(firebaseError, key, { value: err[key] }));
@@ -23,7 +27,7 @@ const _handler = (resolve, reject, errorPrefix, err, resp) => {
   });
 };
 
-export function toWebSDKErrorCode(code, prefix) {
+export function toWebSDKErrorCode(code: any, prefix: string): string {
   if (!code || typeof code !== 'string') return '';
   return code.toLowerCase().replace('error_', prefix).replace(/_/g, '-');
 }
@@ -36,7 +40,11 @@ export function toWebSDKErrorCode(code, prefix) {
  * @param joiner
  * @returns {*}
  */
-export function deepGet(object, path, joiner = '/') {
+export function deepGet(
+  object: Object,
+  path: string,
+  joiner?: string = '/'
+): any {
   const keys = path.split(joiner);
 
   let i = 0;
@@ -60,7 +68,11 @@ export function deepGet(object, path, joiner = '/') {
  * @param joiner
  * @returns {*}
  */
-export function deepExists(object, path, joiner = '/') {
+export function deepExists(
+  object: Object,
+  path: string,
+  joiner?: string = '/'
+): boolean {
   const keys = path.split(joiner);
 
   let i = 0;
@@ -81,7 +93,7 @@ export function deepExists(object, path, joiner = '/') {
  * @param item
  * @returns {boolean}
  */
-export function isObject(item) {
+export function isObject(item: any): boolean {
   return (item && typeof item === 'object' && !Array.isArray(item) && item !== null);
 }
 
@@ -90,8 +102,8 @@ export function isObject(item) {
  * @param item
  * @returns {*|boolean}
  */
-export function isFunction(item) {
-  return (item && typeof item === 'function');
+export function isFunction(item?: any): boolean {
+  return Boolean(item && typeof item === 'function');
 }
 
 /**
@@ -112,7 +124,7 @@ export function tryJSONParse(string) {
  * @param data
  * @returns {*}
  */
-export function tryJSONStringify(data) {
+export function tryJSONStringify(data: any): string | null {
   try {
     return JSON.stringify(data);
   } catch (jsonError) {
@@ -149,7 +161,11 @@ export function noop(): void {
  * @param NativeModule
  * @param errorPrefix
  */
-export function promisify(fn: Function, NativeModule: Object, errorPrefix): Function<Promise> {
+export function promisify(
+  fn: Function | string,
+  NativeModule: Object,
+  errorPrefix?: string
+): (any) => Promise<> {
   return (...args) => {
     return new Promise((resolve, reject) => {
       const _fn = typeof fn === 'function' ? fn : NativeModule[fn];
@@ -168,7 +184,12 @@ export function promisify(fn: Function, NativeModule: Object, errorPrefix): Func
  * @param callback
  * @private
  */
-function _delayChunk(collection, chunkSize, operation, callback): void {
+function _delayChunk(
+  collection: Array<*>,
+  chunkSize: number,
+  operation: Function,
+  callback: Function
+): void {
   const length = collection.length;
   const iterations = Math.ceil(length / chunkSize);
 
@@ -210,7 +231,7 @@ export function each(array: Array, chunkSize?: number, iterator: Function, cb: F
   }, cb);
 }
 
-export function typeOf(value) {
+export function typeOf(value: any): string {
   if (value === null) return 'null';
   if (Array.isArray(value)) return 'array';
   return typeof value;