debian-mirror-gitlab/lib/gitlab/untrusted_regexp/ruby_syntax.rb
2019-04-19 08:11:19 +05:30

43 lines
1.2 KiB
Ruby

# frozen_string_literal: true
module Gitlab
class UntrustedRegexp
# This class implements support for Ruby syntax of regexps
# and converts that to RE2 representation:
# /<regexp>/<flags>
class RubySyntax
PATTERN = %r{^/(?<regexp>.+)/(?<flags>[ismU]*)$}.freeze
# Checks if pattern matches a regexp pattern
# but does not enforce it's validity
def self.matches_syntax?(pattern)
pattern.is_a?(String) && pattern.match(PATTERN).present?
end
# The regexp can match the pattern `/.../`, but may not be fabricatable:
# it can be invalid or incomplete: `/match ( string/`
def self.valid?(pattern)
!!self.fabricate(pattern)
end
def self.fabricate(pattern)
self.fabricate!(pattern)
rescue RegexpError
nil
end
def self.fabricate!(pattern)
raise RegexpError, 'Pattern is not string!' unless pattern.is_a?(String)
matches = pattern.match(PATTERN)
raise RegexpError, 'Invalid regular expression!' if matches.nil?
expression = matches[:regexp]
flags = matches[:flags]
expression.prepend("(?#{flags})") if flags.present?
UntrustedRegexp.new(expression, multiline: false)
end
end
end
end