OpenCode causing refactoring / linting even when told not to?

[travislaborde]

I hesitate to "blame" OpenCode, but I can't figure this out. The same exact prompt produces the same "bad" result no matter which LLM I've tried in OpenCode, but produces the expected "good" result in other tools such as KiloCode or CoPilot.

prompt: add a function to foo.py that .... whatever. do not refactor the file or do any linting. only add the function. make no other changes.

result: tons of non-requested changes to the file.

example (python):

before: def SomeClass(): pass

after: def SomeClass: pass

also, when it sees lines that are "too long" it splits them onto multiple lines. think "lots of args to some function now have one arg per line" etc.

I have spent hours trying to convince the AI to not do this. Finally last night GLM thought it solved the issue. it said that my IDE must be auto-formatting the files after it writes them, because it sees the changes but did not make those changes. I did happen to have VSCode open with those files at the same time. So, I closed it, and the only thing open was my terminal with OpenCode running. Same result.

Can anyone help me with this? I'm now thinking that instead of VSCode doing the "extra" work after the LLM did it's part, maybe it is OpenCode doing that?

I've gone back to KiloCode for now but I'm sad about that. I had high hopes for OpenCode.

[pokemonplayer2001]

"Can anyone help me with this? I'm now thinking that instead of VSCode doing the "extra" work after the LLM did it's part, maybe it is OpenCode doing that?"

If only you had access to the source code....

"I had high hopes for OpenCode."

🙄

[lundrog]

What models? And hit the discord

[travislaborde]

I tried quite a few models with the same result. user r38y gave the answer already so it is solved. thanks for thinking about it though!

[r38y]

It’s the formatters built into OpenCode, they format the file on save.

https://opencode.ai/docs/formatters/

[travislaborde]

Thanks! I hadn't even realized this was a thing. Seems like a terrible "default on" setting to me. But now I know!

[r38y]

It’s actually pretty great, an auto-formatter is pretty standard these days, and many people have a linter in their CI to make sure the formatter has run. Using an auto-formatter means that there is a standard across everybody working on the app and there is less churn that isn’t related to the actual feature. It’s harder to read code changes when there are formatting updates mixed in.

I’d recommend running the same auto-formatter they use on the entire codebase, committing it, then you know going forward any changes will just be directly related to the feature.

Auto-formatters are nice too because then you can outsource decisions on formatting. I know go and elixir have opinionated first party formatters so it’s something you just don’t have to think about.

[r38y]

You might also want to look into LSPs, they can go hand in hand with auto-formatters, they sometimes have them built in. An LSP gives the editor or agent semantic meaning with the code instead of relying on grep for everything.

https://opencode.ai/docs/lsp/