feat: add glsl-language-server support

[BenFradella]

Works, but it looks like the server and/or vim lsp are doing something wrong for the unsupported methods. From what I understand, this isn't something that would be handled here, but correct me if I'm wrong:

[ERROR][2022-07-14 13:55:11] .../lua/vim/lsp.lua:824    "LSP[glslls]"   "on_error"  {  code = "INVALID_SERVER_MESSAGE",  err = {    error = {      code = -32601,      message = "Method 'textDocument/completion' not supported."    },    jsonrpc = "2.0"  }}
[ERROR][2022-07-14 13:56:31] .../lua/vim/lsp.lua:824    "LSP[glslls]"   "on_error"  {  code = "INVALID_SERVER_MESSAGE",  err = {    error = {      code = -32601,      message = "Method 'textDocument/didSave' not supported."    },    jsonrpc = "2.0"  }}
[ERROR][2022-07-14 13:56:44] .../lua/vim/lsp.lua:824    "LSP[glslls]"   "on_error"  {  code = "INVALID_SERVER_MESSAGE",  err = {    error = {      code = -32601,      message = "Method 'shutdown' not supported."    },    jsonrpc = "2.0"  }}

[ranjithshegde]

I have been watching the lsp repo in question for almost a year now. The only feature that is implemented is diagnostics. No completion, hover, definition etc. Does not seem to have most features from Lsp-spec.

Would it be a better candidate for null-ls until the LSP is more mature?

As a side-note: You can configure glslc (a binary that is part of shaderc) via efm-langserver. Null-ls already has glslc for diagnostics handling. Also, I have a working method for glslangValidator (a binary that is part of glslang) that I can share as a gist.

[theHamsta]

I've also added glslc and dxc to https://github.com/mfussenegger/nvim-lint my setup is

  use {
    "mfussenegger/nvim-lint",
    config = function()
      local function select_executables(executables)
        return vim.tbl_filter(function(c)
          return c ~= vim.NIL and vim.fn.executable(c) == 1
        end, executables)
      end
      require("lint").linters_by_ft = {
        markdown = select_executables { "markdownlint" },
        lua = select_executables { "luacheck" },
        glsl = select_executables { "glslc" },
        hlsl = select_executables { "dxc" },
      }
      table.insert(require("lint").linters.glslc.args, "--target-env=vulkan1.3")
      vim.cmd [[au BufEnter,BufWritePost * lua require('lint').try_lint()]]
    end,
  }

I hope this is not spam for anyone in this PR

[ranjithshegde]

Yes, more spam (with instructions). Being able to use functions for parsing stdout is the main reason I switched from emf-langserver to null-ls. Here is a snippet on how to configure glslangValidator

local null_ls = require "null-ls"

local function glsl()
    return {
        method = null_ls.methods.DIAGNOSTICS,
        filetypes = { "glsl" },
        generator = null_ls.generator {
            command = "glslangValidator",
            args = { "--stdin", "-S", "$FILEEXT" },
            to_stdin = true,
            from_stderr = true,
            format = "raw",
            check_exit_code = function(code, stderr)
                local success = code <= 1
                if not success then
                    print(stderr)
                end

                return success
            end,
            on_output = function(params, done)
                if params and params.output then
                    local diagnostics = {}
                    local lines = vim.split(params.output, "\n")
                    local sever, col, row, message = string.match(lines[2], "(%u+):%s(%d+):(%d+):.*:%s+(.*)")

                    table.insert(diagnostics, {
                        row = row,
                        col = col + 1,
                        end_col = col + 2,
                        source = "GLSLang",
                        message = message,
                        severity = require("null-ls.helpers").diagnostics.severities[vim.fn.tolower(sever)],
                    })
                    done(diagnostics)
                else
                    done()
                end
            end,
        },
    }
end

null_ls.register(glsl())