Syntax highlighting in neovim HEEX

Phoenix Forum Questions / Help
1

Are there any plugins/configuration settings that provide syntax highlighting/formatting for eex/heex templates in Neovim? I am trying to setup Neovim for Elixir dev and this seems to be the missing part yet.

2

I am using Treesitter with the elixir and heex plugins installed.

require("nvim-treesitter.configs").setup(
    {
        ensure_installed = {
            "eex",
            "elixir",
            "erlang",
            "heex",
            "html",
            "surface",
            ...
        },
        ...
        highlight = {enable = true},
    }
9 Likes
3

I have syntax highlighting working, but the formatting does not seem to work inside a ~H sigal or .heex file. Any other config I could be missing?

4

I use my LSP to do formatting (I do this on_attach):

local opts = {buffer = 0}
vim.keymap.set("n", "<Leader>f", vim.lsp.buf.formatting, opts)

I prefer to trigger formatting myself rather then on save. Another thing to check for is to make sure you update your elixirls to the latest

5

Yes, I am running 0.11 version of elixir ls. I can format elixir code use key and also format on write. Either of these work with Elixir code, but do not format .heex files or code inside ~H. I am also running Elixir 1.14.1.

In your setup, does it format HEEX?

6

You have to configure the formatter:

https://hexdocs.pm/phoenix_live_view/Phoenix.LiveView.HTMLFormatter.html#module-setup

4 Likes
7

That was it. Not set to format heex templates. Thanks

8

Did you also get html syntax highlighting in eex/heex files ?
Something like mention in the Expected section of this github issue

9

I am using neovim/lunarvim and all is working fine. Only nit I have is it takes a couple of seconds to clear warnings/errors in the editor. So you can fix an issue and after a few the error notification clears. Wish it was more instantaneous.