Has anyone successfully used null-ls with NrrwRgn?

[sjava]

Has anyone successfully used null-ls with NrrwRgn? After I use the NR command, setfiletype javascript, the buffer not attach any source, but edit any js file, can attach prettier source.

[jose-elias-alvarez]

This is interesting, I've never heard of the plugin but does it work with actual LSP servers (e.g. tsserver for JavaScript)? It might be possible to get null-ls to attach, but without the full file a lot of formatters / linters would fail.

[sjava]

I use NrrwRgn to edit similar vue file.NR command create buffer work with LSP servers.I found the buffer's type is acwrite,cause null-ls can't attached.

[jose-elias-alvarez]

Yes, I guess acwrite buffers are technically valid. I was able to get this to work with the following diff:

diff --git a/lua/null-ls/client.lua b/lua/null-ls/client.lua
index b90f903..be7803e 100644
--- a/lua/null-ls/client.lua
+++ b/lua/null-ls/client.lua
@@ -8,10 +8,20 @@ local u = require("null-ls.utils")
 local api = vim.api
 local lsp = vim.lsp
 
+local allowed_buftypes = {
+    [""] = true,
+    ["acwrite"] = true,
+}
+
 local client, id
 
 local should_attach = function(bufnr)
-    if api.nvim_buf_get_option(bufnr, "buftype") ~= "" or api.nvim_buf_get_name(bufnr) == "" then
+    local buftype = api.nvim_buf_get_option(bufnr, "buftype")
+    if not allowed_buftypes[buftype] then
+        return false
+    end
+
+    if api.nvim_buf_get_name(bufnr) == "" then
         return false
     end
 

However, I think some sources will have issues, since they require more information about the file to parse it properly. For example. prettier uses the file extension to determine which parser to use, so you have to use a workaround like this:

-- you'd have to do this for every filetype you use, which is a pain
local parsers = {
    javascript = "babel",
    typescript = "typescript",
}

local sources = {
    null_ls.builtins.formatting.prettier.with({
        extra_args = function(params)
            return { "--parser", parsers[params.ft] }
        end,
    }),
}

With these changes, prettier actually does work as expected, which is surprising. Happy to review a more thorough PR adding support for this.

Edit: to be clear, I think we can support acwrite buffers, but source-specific workarounds like the one above should probably live in the wiki.