Simplify shuffle and sample.

shuffle.js

@@ -1,22 +1,33 @@
-import arrayShuffle from './.internal/arrayShuffle.js'
-import baseShuffle from './.internal/baseShuffle.js'
+import copyArray from './copyArray.js'
 
 /**
  * Creates an array of shuffled values, using a version of the
  * [Fisher-Yates shuffle](https://en.wikipedia.org/wiki/Fisher-Yates_shuffle).
  *
  * @since 0.1.0
- * @category Collection
- * @param {Array|Object} collection The collection to shuffle.
+ * @category Array
+ * @param {Array} array The array to shuffle.
  * @returns {Array} Returns the new shuffled array.
  * @example
  *
  * shuffle([1, 2, 3, 4])
  * // => [4, 1, 3, 2]
  */
-function shuffle(collection) {
-  const func = Array.isArray(collection) ? arrayShuffle : baseShuffle
-  return func(collection)
+function shuffle(array) {
+  const length = array == null ? 0 : array.length
+  if (!length) {
+    return []
+  }
+  let index = -1
+  const lastIndex = length - 1
+  const result = copyArray(array)
+  while (++index < length) {
+    const rand = index + Math.floor(Math.random() * (lastIndex - index + 1))
+    const value = result[rand]
+    result[rand] = result[index]
+    result[index] = value
+  }
+  return result
 }
 
 export default shuffle