read_verilog_module does not support instances with unconnected ports, will generate a TypeError.

[darcy-wu]

from __future__ import absolute_import
from __future__ import print_function
import sys
import os
import collections

# the next line can be removed after installation
sys.path.insert(0, os.path.dirname(os.path.dirname(os.path.dirname(os.path.abspath(__file__)))))

from veriloggen import *

test_v = '''\
module test ();

  wire CLK, RST;
  adder u_adder (
    .clk (CLK),
    .rst (RST),
    .A   (   )    # Please pay attention to this line, as it will trigger a TypeError error, refer below.
  );
endmodule
'''


def mkLed():
    m = from_verilog.read_verilog_module_str(test_v)

    return m['test']


if __name__ == '__main__':
    test = mkLed()
    verilog = test.to_verilog()
    print(verilog)

---

Traceback (most recent call last):
File "projects/user/work/python3/veriloggen-develop/examples/read_verilog_code/read_verilog_code.py", line 33, in
verilog = test.to_verilog()
File "projects/user/work/python3/veriloggen-develop/veriloggen/core/module.py", line 1019, in to_verilog
return to_verilog.write_verilog(obj, filename, for_verilator)
File "projects/user/work/python3/veriloggen-develop/veriloggen/verilog/to_verilog.py", line 20, in write_verilog
module_ast_list = [visitor.visit(mod) for mod in modules
File "projects/user/work/python3/veriloggen-develop/veriloggen/verilog/to_verilog.py", line 20, in
module_ast_list = [visitor.visit(mod) for mod in modules
File "projects/user/work/python3/veriloggen-develop/veriloggen/verilog/to_verilog.py", line 588, in visit
return self.visit_Module(node)
File "projects/user/work/python3/veriloggen-develop/veriloggen/verilog/to_verilog.py", line 611, in visit_Module
items = [self.visit(i) for i in node.items
File "projects/user/work/python3/veriloggen-develop/veriloggen/verilog/to_verilog.py", line 611, in
items = [self.visit(i) for i in node.items
File "projects/user/work/python3/veriloggen-develop/veriloggen/verilog/to_verilog.py", line 593, in visit
return visitor(node)
File "projects/user/work/python3/veriloggen-develop/veriloggen/verilog/to_verilog.py", line 770, in visit_Instance
portlist = [vast.PortArg(p, self.bind_visitor.visit(a))
File "projects/user/work/python3/veriloggen-develop/veriloggen/verilog/to_verilog.py", line 770, in
portlist = [vast.PortArg(p, self.bind_visitor.visit(a))
File "projects/user/work/python3/veriloggen-develop/veriloggen/verilog/to_verilog.py", line 54, in visit
return visitor(node)
File "projects/user/work/python3/veriloggen-develop/veriloggen/verilog/to_verilog.py", line 47, in generic_visit
raise TypeError("Type %s is not supported." % str(type(node)))
TypeError: Type <class 'NoneType'> is not supported.