prototype: Prevent Enumerable#eachSlice from entering into an endless loop if passed an argument smaller than 1. Closes #10665.

CHANGELOG

@@ -1,3 +1,5 @@
+* Prevent Enumerable#eachSlice from entering into an endless loop if passed an argument smaller than 1. Closes #10665. [kangax, Tobie Langel]
+
 * Allow Selector to correctly detect the presence of namespaced attributes. Closes #10987. [Samuel Lebeau, Tobie Langel]
 
 * Make Element#absolutize and Element#relativize always return element. Closes #10983. [kangax]

src/enumerable.js

@@ -17,6 +17,7 @@ var Enumerable = {
   eachSlice: function(number, iterator, context) {
     iterator = iterator ? iterator.bind(context) : Prototype.K;
     var index = -number, slices = [], array = this.toArray();
+    if (number < 1) return array;
     while ((index += number) < array.length)
       slices.push(array.slice(index, index+number));
     return slices.collect(iterator, context);

test/unit/enumerable.html

@@ -164,6 +164,9 @@
         [3, 2, 1, 11, 7, 5, 19, 17, 13, 31, 29, 23, 43, 41, 37, 59, 53, 47, 71, 67, 61, 83, 79, 73, 97, 89],
         Fixtures.Primes.eachSlice( 3, function(slice){ return slice.reverse() }).flatten()
       );
+      assertEnumEqual(Fixtures.Basic, Fixtures.Basic.eachSlice(-10));
+      assertEnumEqual(Fixtures.Basic, Fixtures.Basic.eachSlice(0));
+      assertNotIdentical(Fixtures.Basic, Fixtures.Basic.eachSlice(0));
     }},
     
     testEachWithIndex: function() {with(this) {