Added `Array#product` method

Ruby-1.9.0 feature.

ref: https://docs.ruby-lang.org/ja/3.0.0/method/Array/i/product.html

1 files changed, 22 insertions, 0 deletions

diff --git a/mrbgems/mruby-array-ext/test/array.rb b/mrbgems/mruby-array-ext/test/array.rb
index 3f73ad8b9..879980c7e 100644
--- a/mrbgems/mruby-array-ext/test/array.rb
+++ b/mrbgems/mruby-array-ext/test/array.rb
@@ -421,3 +421,25 @@ assert('Array#transpose') do
   assert_raise(TypeError) { [1].transpose }
   assert_raise(IndexError) { [[1], [2,3,4]].transpose }
 end
+
+assert "Array#product" do
+  assert_equal [[1], [2], [3]], [1, 2, 3].product
+  assert_equal [], [1, 2, 3].product([])
+  assert_equal [], [1, 2, 3].product([4, 5, 6], [])
+
+  expect = [[1, 5, 8], [1, 5, 9], [1, 6, 8], [1, 6, 9], [1, 7, 8], [1, 7, 9],
+            [2, 5, 8], [2, 5, 9], [2, 6, 8], [2, 6, 9], [2, 7, 8], [2, 7, 9],
+            [3, 5, 8], [3, 5, 9], [3, 6, 8], [3, 6, 9], [3, 7, 8], [3, 7, 9],
+            [4, 5, 8], [4, 5, 9], [4, 6, 8], [4, 6, 9], [4, 7, 8], [4, 7, 9]]
+  assert_equal expect, [1, 2, 3, 4].product([5, 6, 7], [8, 9])
+
+  expect = [[1, 4, 7], [1, 4, 8], [1, 4, 9], [1, 5, 7], [1, 5, 8], [1, 5, 9], [1, 6, 7], [1, 6, 8], [1, 6, 9],
+            [2, 4, 7], [2, 4, 8], [2, 4, 9], [2, 5, 7], [2, 5, 8], [2, 5, 9], [2, 6, 7], [2, 6, 8], [2, 6, 9],
+            [3, 4, 7], [3, 4, 8], [3, 4, 9], [3, 5, 7], [3, 5, 8], [3, 5, 9], [3, 6, 7], [3, 6, 8], [3, 6, 9]]
+
+  assert_equal expect, [1, 2, 3].product([4, 5, 6], [7, 8, 9])
+  base = [1, 2, 3]
+  x = []
+  assert_equal base, base.product([4, 5, 6], [7, 8, 9]) { |e| x << e }
+  assert_equal expect, x
+end