Integration with rust-tools.nvim

[mightyiam]

How would I go about integrating this with the following plugin, please?
https://github.com/simrat39/rust-tools.nvim

[VonHeikemen]

It seems rust-tools calls the language server inside their setup function. Means you have to use that. Here is an example.

local lsp = require('lsp-zero')
lsp.preset('system-lsp')

local custom_attach = function(client, bufnr)
  -- some code
end

lsp.on_attach(custom_attach)

lsp.setup_servers({'html', 'cssls'})
lsp.setup()

-- rust-tools setup

local lsp_capabilities = require('cmp_nvim_lsp').update_capabilities(
  vim.lsp.protocol.make_client_capabilities()
)

require('rust-tools').setup({
  server = {
    capabilities = lsp_capabilities,
    on_attach = function(client, bufnr)
      custom_attach(client, bufnr)
      -- more code
    end,
  }
})

Edit: sadly you'll have to setup your own keybindings in on_attach function for rust.

[mightyiam]

What additional API would rust-tools need to have for perfect integration?

[VonHeikemen]

It would be lovely if rust-tools would let you control the call to the server.

require('rust-tools').setup({
  server = function()
    lsp.configure('rust_analyzer')
  end
})

But for the people using the recommended preset it would not work. I would have to add another option to setup the server. Something like this.

lsp.configure('rust_analyzer', {
  setup_client = function(opts, call)
    require('rust-tools').setup({server = opts})
  end
})

[VonHeikemen]

I came up with another idea: add a function that can generate the options necessary to call the language server using nvim-lspconfig.

The updated example for system-lsp preset would be this.

local lsp = require('lsp-zero')
lsp.preset('system-lsp')

lsp.setup_servers({'html', 'cssls'})

lsp.setup()

-- Initialize rust_analyzer with rust-tools
local lsp_rust = lsp.build_options('rust_analyzer', {})
require('rust-tools').setup({server = lsp_rust})

For the recommended preset .build_options should be called before lsp.setup().

local lsp = require('lsp-zero')
lsp.preset('recommended')

local lsp_rust = lsp.build_options('rust_analyzer', {})

lsp.setup()

-- Initialize rust_analyzer with rust-tools
require('rust-tools').setup({server = lsp_rust})

When you use .build_options the language server you specify will be not be setup in lsp-zero. This way there is no conflict with plugins like rust-tools.

[mightyiam]

Since 3b6387e there is a way!