[indent] Over-indentation creates weird interactions with LSP formatter

[zploskey]

I think there is a problem with indentation after lines with bucklescript annotations. For example, with the file (example from near the beginning of reason-react, src/ReactDOMRe.re):

external render : ReasonReact.reactElement => Dom.element => unit =
  "render" [@@bs.val] [@@bs.module "react-dom"];

external _getElementsByClassName : string => array Dom.element =
  "document.getElementsByClassName" [@@bs.val];

external _getElementById : string => option Dom.element =
  "document.getElementById" [@@bs.val] [@@bs.return nullable];

If I go to the end of the first expression (after [@@bs.module "react-dom"];), and insert a new line, the new line is automatically indented by 2 spaces. I think it should not be indented at all, unless we're in a block, surrounded by { }.

This may not sound like a big deal, but it is causing reformatting with vim-lsp and ocaml-language-server using the :LspDocumentFormat command to indent lines following each expression with bucklescript annotations by an additional indentation level. So you wind up with some of these lines being 3 or 4 indentation levels deep when they should actually start at the beginning of the line, and do if you just run refmt --in-place on the file from outside the editor. It winds up looking like this:

external render : ReasonReact.reactElement => Dom.element => unit =
  "render" [@@bs.val] [@@bs.module "react-dom"];

  external _getElementsByClassName : string => array Dom.element =
    "document.getElementsByClassName" [@@bs.val];

    external _getElementById : string => option Dom.element =
      "document.getElementById" [@@bs.val] [@@bs.return nullable];

Moving indent/reason.vim somewhere else makes things indent normally. Looks like an issue with the indent configuration.

[chenglou]

cc @jordwalke

[zploskey]

The other possibility is that prabirshrestha/vim-lsp should not be applying additional indentation to the results of refmt from the language client, I guess. I suspect maybe both of these things need some changes.

[zploskey]

Indeed, autozimu/LanguageClient-neovim doesn't seem to have this problem when you run :call LanguageClient_textDocument_formatting().

[zploskey]

This may not have anything to do with bucklescript annotations. Perhaps just long lines/functions. With vim-lsp this output from refmt --in-place:

external render :
  ReasonReact.reactElement =>
  Dom.element =>
  array Dom.element =>
  Dom.element =>
  array Dom.element =>
  unit =
  "render";

external _getElementsByClassName : string => array Dom.element = "document.getElementsByClassName";

external _getElementById : string => option Dom.element = "document.getElementById";

Formats to this:

external render :
  ReasonReact.reactElement =>
    Dom.element =>
      array Dom.element =>
        Dom.element =>
          array Dom.element =>
            unit =
              "render";

              external _getElementsByClassName : string => array Dom.element = "document.getElementsByClassName";

              external _getElementById : string => option Dom.element = "document.getElementById";

[jordwalke]

Worth trying on the new syntax! If it's suitable, we can close.

[zploskey]

Still seeing over-indentation with :LspDocumentFormat and when entering a new line at the end of any of these functions.

[@bs.val] [@bs.module "react-dom"]
external render : (ReasonReact.reactElement, Dom.element) => unit =
  "render";

  [@bs.val] external _getElementsByClassName : string => array(Dom.element) =
    "document.getElementsByClassName";

    [@bs.val] [@bs.return nullable] external _getElementById : string => option(Dom.element) =
      "document.getElementById";