Pylint Static Code Analysis | Executing with Command Line vs Programmatically

Sheep make wool which makes lint and thats about as creative I can get for this article on code lint.

Pylint is an incredibly useful tool for static code analysis. It provides a simple score out of 10, a detailed output on what to fix, and the ability to ignore things you do not believe in.

Pylint - code analysis for Python | www.pylint.org

This is part one of three of a series I am doing on how I use pylint in my projects.

• Part 1: Executing with Command Line vs Programmatically
• Part 2: Pylint Runner Script with Changeable Threshold

Pylint Static Code Analysis | Python Script with Adjustable Threshold

• Part 3: A Github Action for Failing Builds under a Pylint Threshold

Pylint Static Code Analysis | Github Action to fail below a score threshold

Command Line vs Programmatically

In both of these instances, you will have to install Pylint.

$ pip install pylint

This should give you confirmation it is installed.

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Installing collected packages: pylint
Successfully installed pylint-2.4.4

I will assume your code is in a folder called src/. Now to run on your project with the command line you can run the following.

$ pylint src/

Which should give you some output from the static code analysis followed by a score!

************* Module src.src_hi
src/src_hi.py:6:0: C0103: Constant name "logger" doesn't conform to UPPER_CASE naming style (invalid-name)
************* Module src.src_try
src/src_src.py:11:2: W0511: TODO: test (fixme)
------------------------------------------------------------------
Your code has been rated at 9.55/10 (previous run: 9.55/10, +0.00)

But what if you want to do the same with python code? First make a python file in your project directory at the same level you ran the above script, I will call it simple.py.

lint.py

Then run the python file and you should see the same output as you got before!

$ python simple.py
************* Module src.src_hi
src/src_hi.py:6:0: C0103: Constant name "logger" doesn't conform to UPPER_CASE naming style (invalid-name)
************* Module src.src_try
src/src_src.py:11:2: W0511: TODO: test (fixme)
------------------------------------------------------------------
Your code has been rated at 9.55/10 (previous run: 9.55/10, +0.00)

Now that you know how to run with the command line and from a python script, we can go into a more in depth into utility.

Pylint Static Code Analysis | Python Script with Adjustable Threshold

This code above and from the next to parts of the series can be found on Github!

doedotdev/wool

Thanks!

Personal Note

Real projects should expect much higher scores. My production projects usually are set to have 9 or 9.5 as the score threshold limit. However, I do use additional exclusions that differ from the base Pylint setup.

C0114, # missing-module-docstring
C0115, # missing-class-docstring
C0116, # missing-function-docstring
R0903  # too-few-public-methods

This snippet can be copy and pasted into the disable section of a .pylintrc file and it will ignore those errors and they will not lower your score.