hash.c: same hash values with Float#hash

* hash.c (rb_any_hash): use same hash values with Float#hash so
  that -0.0 and +0.0 will be identical.
  [ruby-core:68541] [Bug #10979]

git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@49999 b2dd03c8-39d4-4d8f-98ff-823fe69b080e

1 files changed, 8 insertions, 0 deletions

diff --git a/test/ruby/test_float.rb b/test/ruby/test_float.rb
index ac2d84352b..073e382777 100644
--- a/test/ruby/test_float.rb
+++ b/test/ruby/test_float.rb
@@ -672,4 +672,12 @@ class TestFloat < Test::Unit::TestCase
     assert_equal(0.0, z)
     assert_equal(-Float::INFINITY, 1.0/z)
   end
+
+  def test_hash_0
+    bug10979 = '[ruby-core:68541] [Bug #10979]' 
+    assert_equal(+0.0.hash, -0.0.hash)
+    assert_operator(+0.0, :eql?, -0.0)
+    h = {0.0 => bug10979}
+    assert_equal(bug10979, h[-0.0])
+  end
 end