building swing from f27 on el7 :: Traceback in copr-rpmbuild

[Adrian Sevcenco]

Hi! I am trying to build a newer swig version for el7 starting from the 
srpm for f27 .. locally on a el7 machine i built the rpm (with java 
removal from original spec) and the resulting srpm i tried to build on 
copr .. but i have some errors that seems not related to package :

https://copr-be.cloud.fedoraproject.org/results/asevcenc/science-utils/sr...

stdout: Downloading swig-3.0.12.tar.gz
stderr: Could not execute srpm: 'ns2'


Traceback (most recent call last):
   File "/usr/bin/copr-rpmbuild", line 96, in main
     action(args, config)
   File "/usr/bin/copr-rpmbuild", line 126, in build_srpm
     provider.produce_srpm()
   File 
"/usr/lib/python3.6/site-packages/copr_rpmbuild/providers/scm.py", line 
115, in produce_srpm
     return run_cmd(cmd, cwd=self.repo_subpath)
   File "/usr/lib/python3.6/site-packages/copr_rpmbuild/helpers.py", 
line 66, in run_cmd
     raise RuntimeError(result.stderr)
RuntimeError: Could not execute srpm: 'ns2'

given that i am really new to copr usage i might miss some procedures ..
does anyone have any idea about the error and/or workflow with copr?
so far my experience is just using copr-cli to upload a srpm..

Thank you!
Adrian