strscan.c: add MatchData-like methods

* ext/strscan/strscan.c: added `size`, `captures` and `values_at`
  to StringScanner, shorthands of accessing the matched data.
  based on the patch by apeiros (Stefan Rusterholz) at
  [ruby-core:20412].  [Feature #836]

git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@60929 b2dd03c8-39d4-4d8f-98ff-823fe69b080e

1 files changed, 22 insertions, 0 deletions

diff --git a/test/strscan/test_stringscanner.rb b/test/strscan/test_stringscanner.rb
index 9fe6ad7125..3423f9cfed 100644
--- a/test/strscan/test_stringscanner.rb
+++ b/test/strscan/test_stringscanner.rb
@@ -728,4 +728,26 @@ class TestStringScanner < Test::Unit::TestCase
     assert_nil(s[:c])
     assert_nil(s["c"])
   end
+
+  def test_size
+    s = StringScanner.new("Fri Dec 12 1975 14:39")
+    s.scan(/(\w+) (\w+) (\d+) /)
+    assert_equal(4, s.size)
+  end
+
+  def test_captures
+    s = StringScanner.new("Fri Dec 12 1975 14:39")
+    s.scan(/(\w+) (\w+) (\d+) /)
+    assert_equal(["Fri", "Dec", "12"], s.captures)
+    s.scan(/(\w+) (\w+) (\d+) /)
+    assert_nil(s.captures)
+  end
+
+  def test_values_at
+    s = StringScanner.new("Fri Dec 12 1975 14:39")
+    s.scan(/(\w+) (\w+) (\d+) /)
+    assert_equal(["Fri Dec 12 ", "12", nil, "Dec"], s.values_at(0, -1, 5, 2))
+    s.scan(/(\w+) (\w+) (\d+) /)
+    assert_nil(s.values_at(0, -1, 5, 2))
+  end
 end