Fixes a bug in Stringends_with?

  iex> String.ends_with? "hello", ["hell", "lo"]
  false

 The problem was that the implementation uses :binary.matches, and that returns only
 one match. It would find "hell", but pos+len != size, and so returned false.

 Changed for a less efficient implementation.

Author: pragdave

lib/elixir/lib/string.ex

@@ -835,10 +835,15 @@ defmodule String do
   """
   @spec ends_with?(t, t | [t]) :: boolean
 
-  def ends_with?(string, suffixes) do
-    string_size = size(string)
-    matches = :binary.matches(string, suffixes)
-    Enum.any? matches, fn({pos, len})-> pos + len == string_size end
+  def ends_with?(string, suffixes) when is_list(suffixes) do
+    string_len = String.length(string)
+    Enum.any? suffixes, 
+                fn suffix ->
+                     len = String.length(suffix)
+                     suffix == String.slice(string, string_len - len, len)
+                end
   end
 
+  def ends_with?(string, suffix), do: __MODULE__.ends_with?(string, [ suffix ])
+
 end

lib/elixir/test/elixir/string_test.exs

@@ -294,6 +294,7 @@ defmodule StringTest do
   test :ends_with? do
     assert String.ends_with? "hello", "lo"
     assert String.ends_with? "hello", "hello"
+    assert String.ends_with? "hello", ["hell", "lo", "xx"]
     assert String.ends_with? "hello", ["hellö", "lo"]
     assert String.ends_with? "エリクシア", "シア"
     refute String.ends_with? "hello", "he"