Custom Injections in Neovim Treesitter with Tagged Template Literals

Question

I'm trying to write a custom injection for Neovim's Treesitter that will highlight tagged template literals as SQL code.

The code in question looks like this:

import sql from "postgres"
const query = sql` SELECT * FROM my_table`

I'd like to tell Treesitter to parse this tagged template literal as SQL code. This is possible using Treesitter's custom injections; in fact the library uses this same technique to inject syntax for GraphQL tagged template literals, which I believe happens in this file here.

I've written a configuration file at ~/.config/nvim/after/queries/ecma/injections.scm that's quite similar to the GraphQL query, and although Treesitter is recognizing the file, the injection isn't working at all. Does anyone have a solution to this? Ideally, Treesitter would see the sql tagged template literal and interpret the body of the function with the SQL parser.

Answer 1

to make tree sitter use injections in your after/ folder, your injections.scm file should contain ; extends as first line.

Took me many hours to figure it out, it's now documented right here