Any advice on picking a Python language server for emacs?
Hi, folks!
I'd like to set up my emacs with lsp-mode and lsp-ui, but I am finding myself in some analysis paralysis. Ruling out the Palantir language server because it's deprecated and because it's Palantir, that still leaves me with fivelanguage server recommendations from lsp-mode.
Anybody have any opinions they'd like to share? Any really bad experiences I should avoid? How do I configure your favorite? (Feel free to assume I know very little about configuring emacs.)
If it makes a difference, I am a poetry user and a religious mypy --strict user.
MS LSP is also deprecated in favor of Microsoft's pylance AFAIK.
I've never used Jedi much, but it's one of the older ones and not very comprehensive to my knowledge. Ruff is relatively new but they already have >800 rules and increasing. Ruff is by far the fastest too.
No thoughts on py-lsp.
Ah, just be sure to enable most (or all) rules with ruff, as the default rule sets are pretty relaxed.
Sounds like things are going very wrong in lsp land. The point of a language server is to support lots of types of tools through an abstracted server. Not to have one server per tool.
Otherwise, just use fly-checker. It can even get information from multiple tools at once.
I forgot pyright: it might be a good choice, but since you like strict mode, see basedpyright instead. I don't know about integrating it with emacs though.
I'd pick between Ruff and (based)pyright - maybe both if that works in emacs.
In VSCode the best answer by far is Pylance, which uses Pyright under the hood for type analysis.
Unfortunately while Pyright is open source, Pylance isn't (part of Microsoft's strategy to maintain control over VSCode), so you can't use it in Emacs.
Still, I would give the Pyright LSP server a try. I haven't used it but I would guess it will give you type error squiggles but maybe not code completion / go-to-definition.
Ruff is really a different thing - it is a linter like Pylint, so it only gives you some hints and fixits. You can maybe install it in addition to Pyright if you can be bothered.
Btw Pyright is far superior to Mypy - even with --strict. I would ditch Mypy asap.