Travis build: 875

README.md

@@ -363,6 +363,7 @@ _30s.average(1, 2, 3);
 * [`bindAll`](#bindall)
 * [`deepClone`](#deepclone)
 * [`deepFreeze`](#deepfreeze)
+* [`deepMapKeys`](#deepmapkeys-)
 * [`defaults`](#defaults)
 * [`dig`](#dig)
 * [`equals`](#equals-)
@@ -6707,6 +6708,66 @@ o[1][0] = 4; // not allowed as well
 
 <br>[⬆ Back to top](#contents)
 
+### deepMapKeys ![advanced](/advanced.svg)
+
+Deep maps an object keys.
+
+Creates an object with the same values as the provided object and keys generated by running the provided function for each key.
+
+Use `Object.keys(obj)` to iterate over the object's keys. 
+Use `Array.prototype.reduce()` to create a new object with the same values and mapped keys using `fn`.
+
+```js
+const deepMapKeys = (obj, f) =>
+  Array.isArray(obj)
+    ? obj.map(val => deepMapKeys(val, f))
+    : typeof obj === 'object'
+      ? Object.keys(obj).reduce((acc, current) => {
+        const val = obj[current];
+        acc[f(current)] =
+            val !== null && typeof val === 'object' ? deepMapKeys(val, f) : (acc[f(current)] = val);
+        return acc;
+      }, {})
+      : obj;
+```
+
+<details>
+<summary>Examples</summary>
+
+```js
+const obj = {
+  foo: '1',
+  nested: {
+    child: {
+      withArray: [
+        {
+          grandChild: ['hello']
+        }
+      ]
+    }
+  }
+};
+const upperKeysObj = deepMapKeys(obj, key => key.toUpperCase());
+/*
+{
+  "FOO":"1",
+  "NESTED":{
+    "CHILD":{
+      "WITHARRAY":[
+        {
+          "GRANDCHILD":[ 'hello' ]
+        }
+      ]
+    }
+  }
+}
+*/
+```
+
+</details>
+
+<br>[⬆ Back to top](#contents)
+
 ### defaults
 
 Assigns default values for all properties in an object that are `undefined`.