Best way to do source code modifications?

[chrisjsewell]

Some examples:

• https://github.com/pytest-dev/unittest2pytest
• https://github.com/asottile/pyupgrade
• https://github.com/PyCQA/isort

[ltalirz]

Just mentioning that we wrote something to help with migration of plugins for the 0.x to 1.x transition that was using bowler https://github.com/aiidateam/aiida-plugin-migrator

[chrisjsewell]

cheers

[chrisjsewell]

Was looking at https://stackoverflow.com/q/768634/5033292, and note in python 3.9 there is now https://docs.python.org/3.9/library/ast.html#ast.unparse which could be useful

[chrisjsewell]

and from that, https://github.com/isidentical/refactor also looks interesting

[mbercx]

Seems pure AST is lossy because it doesn't preserve whitespace/comments?

refactor looks interesting but I can't pip install it for some reason 🤷

Now looking at https://github.com/Instagram/LibCST/

[ltalirz]

and what we used for the previous plugin migrator is not powerful enough?
https://github.com/facebookincubator/Bowler

[mbercx]

Right, I'll have a look at that as well 👍

[mbercx]

In the end I decided to use LibCST over bowler. Although bowler is a nice tool building on other CST packages that provides a very easy API for simple changes, their development seems to be stalled atm (they actually recommend using LibCST), so I figured I'd go straight for the more powerful tool. In the end I was interesting in learning about AST/CST anyways, and was more quickly able to figure out how to e.g. add the core. prefix for factories in LibSCT.