Allow IO#reopen to take a block

* io.c (rb_io_reopen): take a block and ensure the IO closed
  [Feature #2631]

* test/ruby/test_io.rb: add a test

* NEWS: add an entry for this change

git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@59142 b2dd03c8-39d4-4d8f-98ff-823fe69b080e

NEWS

@@ -44,6 +44,7 @@ with all sufficient information, see the ChangeLog file or Redmine
 
   * IO#pread  [Feature #4532]
   * IO#pwrite  [Feature #4532]
+  * IO#reopen takes a block [Feature #2631]
 
 * IOError
 

io.c

@@ -7058,6 +7058,10 @@ rb_io_reopen(int argc, VALUE *argv, VALUE file)
 	}
     }
 
+    if (rb_block_given_p()) {
+	return rb_ensure(rb_yield, file, io_close, file);
+    }
+
     return file;
 }
 

test/ruby/test_io.rb

@@ -2156,6 +2156,22 @@ class TestIO < Test::Unit::TestCase
     }
   end
 
+  def test_reopen_with_block
+    make_tempfile {|t|
+      open(__FILE__) do |f|
+        f.gets
+        assert_nothing_raised {
+          reopened = nil
+          f.reopen(t.path) do |_reopened|
+            reopened = _reopened
+            assert_equal("foo\n", reopened.gets)
+          end
+          assert_equal(true, reopened.closed?)
+        }
+      end
+    }
+  end
+
   def test_reopen_inherit
     mkcdtmpdir {
       system(EnvUtil.rubybin, '-e', <<"End")