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.

首先，使用報告中的位置引數範例，在儲存時觸發程式碼動作的 NeoVim 中重現此問題。接著檢查第 462 行附近的 script/core/code-action.lua，並追蹤 Swap Params 編輯；程式碼動作執行後範例維持不變即表示完成。