coc-settings.json

{
  "diagnostic.refreshOnInsertMode": true,
  "diagnostic.checkCurrentLine": true,
  "diagnostic.warningSign": "--",
  "diagnostic.virtualText": true,
  "diagnostic.virtualTextPrefix": " ■ ",
  "diagnostic.virtualTextCurrentLineOnly": false,
  "coc.preferences.formatOnSaveFiletypes": [
    "elm",
    "typescript",
    "javascript",
    "json",
    "jsonc"
  ],
  "languageserver": {
    "go": {
      "command": "gopls",
      "rootPatterns": [
        "go.mod"
      ],
      "trace.server": "verbose",
      "filetypes": [
        "go"
      ],
    },
    "haskell": {
      "command": "haskell-language-server-wrapper",
      "args": [
        "--lsp"
      ],
      "rootPatterns": [
        "*.cabal",
        "stack.yaml",
        "cabal.project",
        "package.yaml",
        "hie.yaml"
      ],
      "filetypes": [
        "haskell",
        "lhaskell"
      ]
    },
    "elmLS": {
      "command": "elm-language-server",
      "filetypes": [
        "elm"
      ],
      "rootPatterns": [
        "elm.json"
      ],
      "initializationOptions": {
        "elmAnalyseTrigger": "change"
      }
    },
    "nix": {
      "command": "rnix-lsp",
      "filetypes": [
        "nix"
      ]
    }
  },
  // coc-diagnostics for shellcheck, shfmt and so on.
  //
  // Install with :CocInstall coc-diagnostic
  "diagnostic-languageserver.filetypes": {
    "sh": "shellcheck" // lint `sh` (and `bash`) files
  },
  "diagnostic-languageserver.formatFiletypes": {
    "sh": "shfmt", // format `sh` (and `bash`) files
    "nix": "alejandra"
  },
  "diagnostic-languageserver.formatters": {
    // define our formatter so that we can reference it from
    // `diagnostic-languageserver.formatFiletypes`
    "shfmt": {
      "command": "shfmt",
      // all the below args are entirely optional
      // primarily listed here to call out that flags which take an
      // argument (such as `-i <num-spaces>` for specifying indentation)
      // should be split into two strings, the flag and then the value
      "args": [
        "-i",
        "2",
        "-bn",
        "-ci",
        "-sr"
      ]
    }
  }
}