clang-format formatting based on global vim settings

[xavier7179]

Feature description

I was wondering if there is a way to configure clang-format so that it looks for the file first, and, if not present, it does not only apply a preferred style but also sets indentation and tabs vs. space for Vim configurations? If so, could you make an example in the documentation?

[xiaoshihou514]

"File not present", meaning this is a temp buffer that's not saved yet?

[xavier7179]

I apologize. I needed clarification in the first place. I was referring to the -style=file option, which makes the command search for a .clang-format file (making it possible to have project-specific formatting rules)

[xiaoshihou514]

I think that's the default behavior given that the cwd is correct (:pwd)

[xavier7179]

Yes, indeed it is. Nevertheless, the style accepts a list of options that follow the file content structure. Unfortunately, there is no example of how to set them (and re-use the values of indents and tabs vs spaces that you can set with vim).
Moreover, the command accepts a --fallback-style=<string> option that should fall back to a specific style when the file is missing. Although useful, <string> can only be a default style and not a more complex configuration as in the -style version. Thus, I was wondering if your plugin can handle it using an algorithmic approach...

[xiaoshihou514]

I guess I can create an example... That might take a while.
Note that ft("foo"):fmt can take a function, check out the tests.

guard.nvim/spec/format_spec.lua

Line 71 in cc8df48

it('can format with dynamic formatters', function()

If you managed to achieve what you wanted I am just going to put your solution as an example :)

[xiaoshihou514]

Screencast_20241025_172410.mp4

@xavier7179

local ft = require("guard.filetype")

ft("c"):fmt(function()
	---@diagnostic disable-next-line: undefined-field
	if vim.uv.fs_stat(".clang-format") then
		return {
			cmd = "clang-format",
			stdin = true,
		}
	else
		return {
			cmd = "clang-format",
			args = {
				("--style={BasedOnStyle: llvm, IndentWidth: %d, TabWidth: %d, UseTab: %s}"):format(
					vim.bo.shiftwidth,
					vim.bo.tabstop,
					vim.bo.expandtab and "Never" or "Always"
				),
			},
			stdin = true,
		}
	end
end)

Feel free to tweak it according to your needs.

[xavier7179]

Thanks for the help! You are the first to support something like this. I really appreciate it (as I'm doing for your plugin, which is very unique if you program in C/C++)