parse.y: zero codepoints

* parse.y (parser_tokadd_utf8): relax restriction to allow zero or
  more codepoints.  fixup r59417.

  https://github.com/ruby/ruby/commit/7e8b910#commitcomment-25602670

git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@60766 b2dd03c8-39d4-4d8f-98ff-823fe69b080e

1 files changed, 6 insertions, 0 deletions

diff --git a/test/ruby/test_parse.rb b/test/ruby/test_parse.rb
index 8830dbec30..dc461e6599 100644
--- a/test/ruby/test_parse.rb
+++ b/test/ruby/test_parse.rb
@@ -517,6 +517,8 @@ class TestParse < Test::Unit::TestCase
     assert_syntax_error(src, /:#{__LINE__}: unterminated/o)
 
     assert_syntax_error('"\u{100000000}"', /invalid Unicode escape/)
+    assert_equal("", eval('"\u{}"'))
+    assert_equal("", eval('"\u{ }"'))
 
     assert_equal("\x81", eval('"\C-\M-a"'))
     assert_equal("\177", eval('"\c?"'))
@@ -555,6 +557,10 @@ class TestParse < Test::Unit::TestCase
     assert_nothing_raised(SyntaxError, bug) do
       assert_equal(sym, eval(':"foo\u{0}bar"'))
     end
+    assert_nothing_raised(SyntaxError) do
+      assert_equal(:foobar, eval(':"foo\u{}bar"'))
+      assert_equal(:foobar, eval(':"foo\u{ }bar"'))
+    end
   end
 
   def test_parse_string