The Story of a Python & a Vulture

Maintaining a high level of code quality is important for any serious project. One aspect of this is ensuring that all code is actually used. There are many reasons for dead code ending up in a project.The most common is refactoring, but another is misspellings, which are only detected at runtime for dynamic languages. Finding and removing dead code allows to keep the code base clean and reduces bugs.

This talk is focused on how we can use Vulture to find dead code. It helps you find unused code in Python programs and it is useful for cleaning up and finding errors in large code bases. If you run Vulture on both your library and test suite you can find untested code. Due to Python's dynamic nature, static code analyzers like Vulture are likely to miss some dead code. Also, code that is only called implicitly may be reported as unused. Nonetheless, Vulture can be a very helpful tool for higher code quality.

Transcript

1. THE STORY OF A PYTHON & VULTURE Rahul Jha PyCon India 2019
2. HI, I’M RJ722 - Student - Open Source Pythonista - Part of Open Source communities
3. LINKS Blog: https://rj722.github.io Twitter: @rahul722j
4. DEAD CODE?
5. import tensorflow as tf if __name__ == '__main__': print("Hello World")
6. MORE DEAD CODE Variables defined, but not used. Code after return statements Unsatisfiable Boolean conditions.
7. SEEMS LEGIT! But I’m not stupid! Why would I write it?
9. Debugging Refactoring Spelling Mistakes HOW IT CRAWLS IN
10. OKAY COOL! Why do I care?
11. NOT COOL! Bugs Code Quality Confusion + Maintenance Overhead Program Size
12. IS THERE A WAY OUT? Yes, Milord! Vulture
13. DEMO Everything will go smoothly!
14. AST 5+(10*2)
16. if number > 5: return 'Bigger than 5' else: return 'Not bigger than 5'
17. BEAUTIFUL DRAWINGS Toby Osbourn https://tosbourn.com/abstract- syntax-trees/
18. def greet(greet_name): print(f'Hello,{greet_name}!')
19. print arguments name = ‘greet' FunctionDef greet_name ‘Hello,’ + greet_name
20. person = 'Guido' def greet(greet_name): print(f'Hello {greet_name}!') if __name__ == '__main__': print(f'Hello {person}!')
22. USED DEFINED person greet UNUSED person greet
24. # whitelist.py unused_function
25. # Automatic $ vulture --make-whitelist .
26. VULTURE IS AWESOME! (How) can I help ?
27. WE ARE OPEN SOURCE https://github.com/jendrikseipp/vulture Come collaborate with us! Devsprints 14-15 October
28. CREDITS Husain Haider Zaidi (@husainhz7) Pradyun Gedam (@pradyunsg) Prajjwal Nijhara (@pnijhara) Prateek Jain (@prateekj117) Satwik Kansal (@satwikkansal)
29. THAT’S ALL FOLKS! Blog: https://rj722.github.io Twitter: @rahul722j Slides: https://gg.gg/rj722-pycon-in