* array.c (rb_ary_combination): Support for Array#combination.size

  [Feature #6636]

git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@37502 b2dd03c8-39d4-4d8f-98ff-823fe69b080e

1 files changed, 5 insertions, 0 deletions

diff --git a/test/ruby/test_enumerator.rb b/test/ruby/test_enumerator.rb
index a4222f2ac0..90718b29cb 100644
--- a/test/ruby/test_enumerator.rb
+++ b/test/ruby/test_enumerator.rb
@@ -441,6 +441,11 @@ class TestEnumerator < Test::Unit::TestCase
     assert_equal 24, [0, 1, 2, 4].permutation.size
     assert_equal 2933197128679486453788761052665610240000000,
       (1..42).to_a.permutation(30).size # 1.upto(42).inject(:*) / 1.upto(12).inject(:*)
+
+    check_consistency_for_combinatorics(:combination)
+    assert_equal 28258808871162574166368460400,
+      (1..100).to_a.combination(42).size
+      # 1.upto(100).inject(:*) / 1.upto(42).inject(:*) / 1.upto(58).inject(:*)
   end
 end