improve type handling and logging

Author: acdvs

lib/useObjectState.js

@@ -1,44 +1,57 @@
 'use strict';
 
-import React, { useState } from 'react';
+import { useState } from 'react';
+
+function useObjectState(initObject) {
+  if (!isFilledObject(initObject)) {
+    console.warn('A non-empty object must be provided to useObjectState. State not created.');
+    return [];
+  }
 
-function useObjectState(initObject = {}) {
   const [state, setState] = useState(initObject);
 
   const updateObject = (partialState) => {
-    let partial = partialState;
-
-    if (typeof partial === 'function') {
-      partial = partialState(state);
+    if (typeof partialState === 'function') {
+      partialState = partialState(state);
     }
 
-    if (
-      !partial ||
-      typeof partial !== 'object' ||
-      Object.keys(partial).length === 0
-    ) {
-      console.error('Object or function returning object must be passed to useObjectState setter. State not updated.');
+    if (!isFilledObject(partialState)) {
+      console.warn('An object or function returning an object must be passed to useObjectState setter. State not updated.');
       return;
     }
 
     let stateCopy = Object.assign({}, state);
-    let stateKeys = Object.keys(stateCopy);
+    const stateKeys = Object.keys(stateCopy);
 
-    for (let [key, val] of Object.entries(partial)) {
-      if (stateKeys.includes(key)) {
-        if (typeof stateCopy[key] === 'object') {
-          Object.assign(stateCopy[key], val);
+    for (const [partialKey, partialVal] of Object.entries(partialState)) {
+      if (stateKeys.includes(partialKey)) {
+        if (typeof stateCopy[partialKey] === 'object') {
+          Object.assign(stateCopy[partialKey], partialVal);
         } else {
-          stateCopy[key] = val;
+          stateCopy[partialKey] = partialVal;
         }
       }
     }
 
     setState(stateCopy);
-  }
+  };
 
-  // Provide initial/changed object and function to component
   return [state, updateObject];
 }
 
-export default useObjectState;
+function isFilledObject(obj) {
+  if (
+    !obj ||
+    typeof obj !== 'object' ||
+    Object.keys(obj).length === 0
+  ) {
+    return false;
+  }
+
+  return true;
+}
+
+export default useObjectState;
+export {
+  isFilledObject
+};