Fix generating invalid trailing commas in import statements

[davidshepherd7]

Summary

Fixes #532

Test Plan

Unit tests added/tweaked for this case, also the remove imports codemod tests serve as an integration test.

[facebook-github-bot]

Hi @davidshepherd7!

Thank you for your pull request and welcome to our community.

Action Required

In order to merge any pull request (code, docs, etc.), we require contributors to sign our Contributor License Agreement, and we don't seem to have one on file for you.

Process

In order for us to review and merge your suggested changes, please sign at https://code.facebook.com/cla. If you are contributing on behalf of someone else (eg your employer), the individual CLA may not be sufficient and your employer may need to sign the corporate CLA.

Once the CLA is signed, our tooling will perform checks and validations. Afterwards, the pull request will be tagged with CLA signed. The tagging process may take up to 1 hour after signing. Please give it that time before contacting us about it.

If you have received this in error or have any questions, please contact us at [email protected]. Thanks!

[facebook-github-bot]

Thank you for signing our Contributor License Agreement. We can now accept your code for this (and any) Meta Open Source project. Thanks!

[zsol]

Thanks for your contribution! This all looks good to me. The logic will also need to be ported to

LibCST/native/libcst/src/nodes/statement.rs

Line 782 in 46509dd

for (i, alias) in aliases.iter().enumerate() {

before merging.

[Kludex]

Hello. Something I can do to speed up this?

[davidshepherd7]

Hello. Something I can do to speed up this?

Yeah, I don't really have time for open source work these days so if someone can figure out and implement the missing rust part that would speed things up a lot.

[sureshjoshi]

Are the Rust and Python implementations intended to be kept in lock-step?

I just started using libcst and ran into this bug, but it looks like it was "partially" solved already?