signal.c: nil for invalid signum

* signal.c (sig_signame): return nil if the argument is a valid
  signal number.

git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@49801 b2dd03c8-39d4-4d8f-98ff-823fe69b080e

1 files changed, 9 insertions, 0 deletions

diff --git a/test/ruby/test_signal.rb b/test/ruby/test_signal.rb
index 4a59aa66c8..781045d30a 100644
--- a/test/ruby/test_signal.rb
+++ b/test/ruby/test_signal.rb
@@ -218,6 +218,15 @@ class TestSignal < Test::Unit::TestCase
   end
 
   def test_signame
+    Signal.list.each do |name, num|
+      assert_equal(num, Signal.list[Signal.signame(num)], name)
+    end
+    assert_nil(Signal.signame(-1))
+    signums = Signal.list.invert
+    assert_nil(Signal.signame((1..1000).find {|num| !signums[num]}))
+  end
+
+  def test_signame_delivered
     10.times do
       IO.popen([EnvUtil.rubybin, "-e", <<EOS, :err => File::NULL]) do |child|
         Signal.trap("INT") do |signo|