Jenkins with pylint gives build failure

Question

I added a build step to execute a Python script.
In this script pylint is called with the lint.Run(..args) to check the code.
The script works but in the end, the bu

Answer 1

Pylint has the unpleasant behavior to return a non-zero exit code even only if a small warning issue was found. Only when everything was fine, 0 is returned (see man page).

As usually a non-zero code denotes an error, Jenkins fails the build.

I see two ways to overcome this:

• Use a small script around pylint that always returns 0. Then jenkins will not fail because of pylint. I use a small python script calling pylint with os.system() and sys.exit(0) after than. You can see it as overriding the error code of pylint.
• Patch pylint. For example, on my Linux system the sys.exit() call is in the file /usr/lib/pymodules/python2.6/pylint/lint.py

Answer 2

Ran into this today (although not using Jenkins).

In my case it was because of how Pylint encodes fatal-error-warning-refactor-convention-usage info in its exit code: https://docs.pylint.org/en/1.6.0/run.html#exit-codes

My fix:

#!/usr/bin/env sh

# Wraps Pylint invocation to produce shell-friendly exit codes
# Because Pylint exit codes are weird:
# https://docs.pylint.org/en/1.6.0/run.html#exit-codes

PYTHON_EXECUTABLE=python
if [ ! -z $PYTHON_ENV ]; then
    PYTHON_EXECUTABLE="$PYTHON_ENV/bin/python"
fi

${PYTHON_EXECUTABLE} -m pylint $@

PYLINT_EXIT_CODE=$?

exit $(($PYLINT_EXIT_CODE % 4))

(Gist: https://gist.github.com/nkashy1/ae59d06d4bf81fb72047fcd390d08903)