From 9262e493d56610d64fe132097f70b3e8e2033b59 Mon Sep 17 00:00:00 2001
From: lvl0nax <lvl0nax@gmail.com>
Date: Fri, 6 May 2016 19:15:51 +0300
Subject: [PATCH] Array#split refactoring for case with block
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Calculating -------------------------------------
              before    26.319k i/100ms
               after    29.414k i/100ms
-------------------------------------------------
              before    350.623k (± 1.6%) i/s -      1.763M
               after    416.227k (± 1.4%) i/s -      2.088M

Comparison:
               after:   416226.8 i/s
              before:   350622.8 i/s - 1.19x slower
---
 .../active_support/core_ext/array/grouping.rb   | 17 ++++++-----------
 1 file changed, 6 insertions(+), 11 deletions(-)

diff --git a/activesupport/lib/active_support/core_ext/array/grouping.rb b/activesupport/lib/active_support/core_ext/array/grouping.rb
index 34af83d1ab..ea9d85f6e3 100644
--- a/activesupport/lib/active_support/core_ext/array/grouping.rb
+++ b/activesupport/lib/active_support/core_ext/array/grouping.rb
@@ -89,24 +89,19 @@ class Array
   #   [1, 2, 3, 4, 5].split(3)              # => [[1, 2], [4, 5]]
   #   (1..10).to_a.split { |i| i % 3 == 0 } # => [[1, 2], [4, 5], [7, 8], [10]]
   def split(value = nil)
+    arr = self.dup
+    result = []
     if block_given?
-      inject([[]]) do |results, element|
-        if yield(element)
-          results << []
-        else
-          results.last << element
-        end
-
-        results
+      while (idx = arr.index { |i| yield i })
+        result << arr.shift(idx)
+        arr.shift
       end
     else
-      arr = self.dup
-      result = []
       while (idx = arr.index(value))
         result << arr.shift(idx)
         arr.shift
       end
-      result << arr
     end
+    result << arr
   end
 end