1 files changed, 10 insertions, 0 deletions
diff --git a/mrbgems/mruby-array-ext/test/array.rb b/mrbgems/mruby-array-ext/test/array.rb
index 650e49642..ab7a24df7 100644
--- a/mrbgems/mruby-array-ext/test/array.rb
+++ b/mrbgems/mruby-array-ext/test/array.rb
@@ -156,3 +156,13 @@ assert("Array#rotate") do
   assert_equal ["c", "d", "a", "b"], a.rotate(10)
   assert_equal [], [].rotate
 end
+
+assert("Array#rotate!") do
+  a = ["a", "b", "c", "d"]
+  assert_equal ["b", "c", "d", "a"], a.rotate!
+  assert_equal ["b", "c", "d", "a"], a
+  assert_equal ["d", "a", "b", "c"], a.rotate!(2)
+  assert_equal ["a", "b", "c", "d"], a.rotate!(-3)
+  assert_equal ["c", "d", "a", "b"], a.rotate(10)
+  assert_equal [], [].rotate!
+end