Server specific settings for eglot-ignored-server-capabilities?

[shipmints]

What is the recommended configuration method to establish eglot-ignored-server-capabilities server by server? e.g., some servers have very slow implementations of some capabilities while others are acceptable. I don't see a way to enable capabilities for the good servers and disable them for bad servers.

[joaotavora]

Set this variable buffer-locally in your major-mode's hook via Elisp's setq-local.

[shipmints]

Good. I figured that's what would be recommended but wasn't quite sure since the user option was not defined as a buffer local and the docstring is silent on this use case.

[shipmints]

How can I tell which server was selected by the user when they run M-x eglot and make the appropriate adjustments if this is set in the mode hook before eglot ever starts?

[shipmints]

Perhaps an eglot-workspace-configuration, when a function, could return a cons with car being the usual workspace config, and cdr being eglot-ignored-server-capabilities, or some structured version of same an alist or a plist.

[joaotavora]

Good. I figured that's what would be recommended but wasn't quite sure since the user option was not defined as a buffer local and the docstring is silent on this use case.

user options are never defined as buffer local, but they are variables, and they have all properties of variables. It'd be silly to restate them in every docstring.

How can I tell which server was selected by the user when they run M-x eglot and make the appropriate adjustments if this is set in the mode hook before eglot ever starts?

You can either infer from the major mode or set it after the server starts, maybe consulting the return value of eglot-current-server (though i don't know if that tells you much, maybe it does). The capabilites are consulted at runtime, so that's not an issue.

Perhaps an eglot-workspace-configuration, when a function, could return a cons with car being the usual workspace config, and cdr being eglot-ignored-server-capabilities, or some structured version of same an alist or a plist.

That wouldn't help. The mention of a server in eglot-workspace-configuration is totally meaningless to Emacs/Eglot, only to whoever is receiving on the other end. So pylsp probably ignored a clangd section of eglot-w-c and likewise. So that car/cdr case wouldn't bring any disambiguation advantage over the buffer-local setting of eglot-w-c, which brings you to the buffer-local-setting of eglot-ignored-server-capabilities.

Eglot has no special notion of what server it is running beyond what is encoded in eglot-server-programs, and it's probably not going to gain any such notion soon.

If you want to disable certain server's capabilities, it probably makes much more sense to disable those capabilities in the server.