Filetype highlights with Nightly

[olimorris]

As discussed over on #79, the rules for defining highlights have changed. This is really interesting for how filetype highlights are applied.

Currently, for my ruby setup, I have the following:

ft_highlights = {
  ruby = {
     TSFunction = { fg = "${blue}", style = "bold" },
     TSInclude = { fg = "${blue}", style = "italic" },
     TSParameter = { fg = "${fg}", style = "italic" },
     TSSymbol = { fg = "${cyan}" },
   },
}

however that could now be replaced by:

highlights = {
  ["@function.ruby"] = { fg = "${blue}", style = "bold" },
  ["@function.call.ruby"] = { fg = "${blue}", style = "bold" },
  ["@include.ruby"] = { fg = "${blue}", style = "italic" },
  ["@parameter.ruby"] = { fg = "${fg}", style = "italic" },
  ["@symbol.ruby"] = { fg = "${cyan}" },
}

What's fantastic is that this is wayyyyy faster than the current implementation and it works in any plugin that uses Treesitter for highlights such as Telescope.

I think when Neovim 0.8 is released, I will consider deprecating the functionality and adding in optional opinionated Filetype Highlights as per the Roadmap.

Be interesting to see if anyone else has played with the new functionality.