Ideas for diagnostic support

[ndonfris]

Hi all! 👋

I'm currently working on implementing an updated diagnostic handler here.

I'm wondering if anyone has any ideas for diagnostic messages to support.

Current Ideas

name	type	description
block end missing	error	for|while|switch|function|if|begin is missing an end token
string missing closing character	error	' or " is missing from string
subshell missing end character	error	( needs end character )
command/builtin prefix missing	warning	command/builtin prefix is missing (user will be able to opt into this behavior through env variables)
missing completions file	info	functions/<file>.fish does not have completions file
autoloaded function file does not have matching function	error	functions/<file>.fish does not have a function matching the filename
invalid fish_lsp_* env variable value	error	bad value for fish_lsp_* variable
single quote includes variable expansion symbol	warning	echo '$some_variable'
0 indexed array	error	echo $argv[0] - fish indexing starts at 1
unused local symbol	warning	local definition in file is unused
missing silent flag	warning	if command -q some_cmd or if set -q some_var is missing
universal definition in script	warning	don't use --universal definitions in fish script, use --universal during interactive use (use '--global' instead)
alias used instead of function	information	use function instead of alias
function missing return status number	warning	return 0 missing from function
source file not found	error	source file.fish file does not exist
private function missing underscore prefix	warning	autoloaded function with private function definition is missing function __private_func

[tippfehlr]

just curious, why is it recommended to use a function instead of alias?

[ndonfris]

Internally, fish-shell defines alias as a wrapper for functions.

For example you could see this behavior based off of the following two commands:

alias ls 'exa'

functions -a ls

This command will output the following definition for the alias ls:

# Defined via `source`
function ls --wraps=exa --description 'alias ls exa'
  exa $argv
        
end

Which is the main reasoning I included this diagnostic message. Having said that, I do still use aliases in my own configuration, and just disable the alias diagnostic via:

set -gx fish_lsp_diagnostic_disable_error_codes 2002