[Feature #18788] Support options as `String` to `Regexp.new`

`Regexp.new` now supports passing the regexp flags not only as an
`Integer`, but also as a `String.  Unknown flags raise errors.

1 files changed, 17 insertions, 0 deletions

diff --git a/test/ruby/test_regexp.rb b/test/ruby/test_regexp.rb
index 5ee6b1b03c..1d93d1a5b1 100644
--- a/test/ruby/test_regexp.rb
+++ b/test/ruby/test_regexp.rb
@@ -634,6 +634,23 @@ class TestRegexp < Test::Unit::TestCase
     end
   end
 
+  def test_initialize_option
+    assert_equal(//i, Regexp.new("", "i"))
+    assert_equal(//m, Regexp.new("", "m"))
+    assert_equal(//x, Regexp.new("", "x"))
+    assert_equal(//imx, Regexp.new("", "imx"))
+    assert_equal(//, Regexp.new("", ""))
+    assert_equal(//imx, Regexp.new("", "mimix"))
+
+    assert_raise(ArgumentError) { Regexp.new("", "e") }
+    assert_raise(ArgumentError) { Regexp.new("", "n") }
+    assert_raise(ArgumentError) { Regexp.new("", "s") }
+    assert_raise(ArgumentError) { Regexp.new("", "u") }
+    assert_raise(ArgumentError) { Regexp.new("", "o") }
+    assert_raise(ArgumentError) { Regexp.new("", "j") }
+    assert_raise(ArgumentError) { Regexp.new("", "xmen") }
+  end
+
   def test_match_control_meta_escape
     assert_equal(0, /\c\xFF/ =~ "\c\xFF")
     assert_equal(0, /\c\M-\xFF/ =~ "\c\M-\xFF")