%script
click -e "
i :: Idle
rw :: IPRewriter(pattern 1.0.0.1 1 - - 0 1,
  pattern 1.0.0.1 1-65535 - - 0 1,
  pattern 1.0.0.1 - - - 0 1)
i -> [0]rw i[1] -> [1]rw i[2] -> [2]rw
rw[0] -> i rw[1] -> i
" -h rw.patterns -q

click -e "
i :: Idle
rw :: IPAddrRewriter(pattern 1.0.0.1 1x - - 0 1,
  pattern 1.0.0.0 0-255 - - 0 1,
  pattern 1.0.0.0 456-19 - - 0 1,
  pattern 1.0.0.0 456-65536 - - 0 1)
i -> [0]rw i[1] -> [1]rw i[2] -> [2]rw i[3] -> [3]rw
rw[0] -> i rw[1] -> i
" 2>X || true

%expect stdout
1.0.0.1 1 - - [0]
1.0.0.1 1-65535 - - [0]
1.0.0.1 - - - [0]

%expect X
  input spec 0: bad source port
  input spec 1: bad source port
  input spec 2: bad source port
  input spec 3: bad source port
Router could not be initialized!

%ignore X
<expr.*