class SimpleCov::RegexFilter

configured Regexp.
Filter that matches when the source file’s project path matches the

def matches?(source_file)

rspec-mocks 4's stricter predicate-matcher type check.
would return the match position (an Integer or nil), which trips
Uses `Regexp#match?` so the predicate returns a real boolean — `=~`
regex configured when initializing this Filter with RegexFilter.new(/someregex/).
Returns true when the given source file's filename matches the 
def matches?(source_file)
  filter_argument.match?(source_file.project_filename)
end