coc-config.json

{
  "flutter.enabled": true,
  "coc.preferences.formatOnSaveFiletypes": [
    "dart",
    "python",
    "rescript"
  ],
  "flutter.lsp.initialization.onlyAnalyzeProjectsWithOpenFiles": false,

  "python.analysis.autoImportCompletions": true,
  "python.formatting.provider": "autopep8",

  "eslint.autoFixOnSave": true,
  "eslint.autoFix": true,

  "languageserver": {
    "haskell": {
      "command": "hie-wrapper",
      "args": ["--lsp"],
      "rootPatterns": [
        "*.cabal",
        "stack.yaml",
        "cabal.project",
        "package.yaml"
      ],
      "filetypes": [
        "hs",
        "lhs",
        "haskell"
      ],
      "initializationOptions": {
        "languageServerHaskell": {
          "hlintOn": true
        }
      }
    },
    "ccls": {
      "command": "ccls",
      "filetypes": [
        "c",
        "cpp",
        "objc",
        "objcpp"
      ],
      "rootPatterns": [
        ".ccls",
        "compile_commands.json",
        ".vim/",
        ".git/",
        ".hg/"
      ],
      "initializationOptions": {
          "cache": {
            "directory": "/tmp/ccls"
          },
          "client": {
            "snippetSupport": true
         },
         "completion": {
           "placeholder": true
         },
         "highlight": { "lsRanges" : true }
      }
    },
    "rescript": {
      "enable": true,
      "module": "~/.vim/plugged/vim-rescript/rescript-vscode/extension/server/out/server.js",
      "args": ["--node-ipc"],
      "filetypes": ["rescript"],
      "rootPatterns": ["bsconfig.json"]
    }
  }
}