compar.c: inversed comarison without infinite recursion

* compar.c (rb_invcmp): compare by inversed comarison, with preventing
  from infinite recursion.  [ruby-core:52305] [Bug #7870]
* string.c (rb_str_cmp_m), time.c (time_cmp): get rid of infinite
  recursion.

git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@39292 b2dd03c8-39d4-4d8f-98ff-823fe69b080e

1 files changed, 7 insertions, 0 deletions

diff --git a/test/ruby/test_comparable.rb b/test/ruby/test_comparable.rb
index 00ce6b485a..c686adeceb 100644
--- a/test/ruby/test_comparable.rb
+++ b/test/ruby/test_comparable.rb
@@ -69,4 +69,11 @@ class TestComparable < Test::Unit::TestCase
     assert_raise(ArgumentError) { 1.0 < nil }
     assert_raise(ArgumentError) { 1.0 < Object.new }
   end
+
+  def test_inversed_compare
+    bug7870 = '[ruby-core:52305] [Bug #7870]'
+    assert_nothing_raised(SystemStackError, bug7870) {
+      assert_nil(Time.new <=> "")
+    }
+  end
 end