Swap Params codeAction breaks code

How are you using the lua-language-server?

NeoVim

Which OS are you using?

MacOS

What is the issue affecting?

Formatting

Expected Behaviour

Write lua code in neovim with codeActions triggered on buffer save. The lua code looks like the following:

vim.api.nvim_create_autocmd('BufWritePre', {})

and save, it will remain unchanged.

Actual Behaviour

It changes the code to the following:

vim.api.nvim_create_autocmd({}, 'BufWritePre')

Reproduction steps

1. Install lua-language-server
2. Setup lua lsp in neovim (can expand if needed)
3. Add the following autocmd to run codeactions on save

vim.api.nvim_create_autocmd('BufWritePre', {
	group = vim.api.nvim_create_augroup('auto-format', { clear = false }),
	buffer = ev.buf,
	callback = function(evt)
		local params = vim.lsp.util.make_range_params()
		params.context = { }
		local result = vim.lsp.buf_request_sync(evt.buf, "textDocument/codeAction", params)
		for _, res in pairs(result or {}) do
			for _, r in pairs(res.result or {}) do
				if r.edit then
					local enc = client.offset_encoding or "utf-16"
					vim.lsp.util.apply_workspace_edit(r.edit, enc)
				end
			end
		end

		vim.lsp.buf.format({ bufnr = ev.buf, id = client.id, timeout_ms = 1000, async = false })
	end,
})

4. Write some lua code and save that lua code with the cursor still on the same line.

Additional Notes

I was editing my neovim config and the lsp kept switching params like the following:

vim.api.nvim_create_autocmd('BufWritePre', {})

And after my PreWrite autocmd calls codeActions

vim.api.nvim_create_autocmd({}, 'BufWritePre')

which immediately breaks the code because the params are position sensitive.

It only does this if the cursor is on the line of the method call which I suppose makes sense since the code action is called with a range. My full autocmd works like this:

vim.api.nvim_create_autocmd('BufWritePre', {
	group = vim.api.nvim_create_augroup('auto-format', { clear = false }),
	buffer = ev.buf,
	callback = function(evt)
		local params = vim.lsp.util.make_range_params()
		params.context = { }
		local result = vim.lsp.buf_request_sync(evt.buf, "textDocument/codeAction", params)
		for _, res in pairs(result or {}) do
			for _, r in pairs(res.result or {}) do
				if r.edit then
					local enc = client.offset_encoding or "utf-16"
					vim.lsp.util.apply_workspace_edit(r.edit, enc)
				end
			end
		end

		vim.lsp.buf.format({ bufnr = ev.buf, id = client.id, timeout_ms = 1000, async = false })
	end,
})

I narrowed it down to this code action here https://github.com/LuaLS/lua-language-server/blob/b5e57c36a9a27b89eb283861fb8946fa787e37d8/script/core/code-action.lua#L462

Maybe I am holding it wrong and it is not supposed to be used in this way but I don't have a problem with other LSPs.

Log File

No log entry was added during this behaviour.

まず、レポートにある位置引数の例を使い、保存時にコードアクションがトリガーされる NeoVim で問題を再現します。次に、script/core/code-action.lua の 462 行目付近を調べ、「Swap Params」編集を追跡します。コードアクションの実行後も例が変更されない状態になれば完了です。