Lsp issue when using [@react.component] inside a module

[benbellick]

The Ocaml lsp seems to be broken when used with reason-react. For example, turning on the LSP and using eglot from within emacs, and then navigating to the first line of the below sample yields the error pasted below:

module Broken = {
  [@react.component]
    let make =
    (
      ~message: string
    ) => <p> {React.string(message)} </p>;
};

⛔ Warning (jsonrpc): Invalid JSON: (unable to decode byte 0xc0 1 193 193) {"params":{"message":"An error occured while querying ocamlformat:\nInput type: {\n external makeProps:\n (~message: string, ~key: string=?, unit) => {.. "message": string} = ""\n "����\u0000\u0000\u0000\u001b\u0000\u0000\u0000\u000b\u0000\u0000\u0000\u001e\u0000\u0000\u0000\u001d���A�'message��A�#key@��@@@";\n let make: {.. "message": string} => React.element;\n}\n\nAnswer: ocamlformat-rpc: ignoring "" (syntax error)\nFile "", line 1, characters 5-6:\nError: Syntax error\nocamlformat-rpc: ignoring "" (syntax error)\nFile "", line 1, characters 0-5:\nError: Syntax error\nocamlformat-rpc: ignoring "" (syntax error)\nFile "", line 1, characters 5-6:\nError: Syntax error\nocamlformat-rpc: ignoring "" (syntax error)\nFile "", line 1, characters 0-1:\nError: Syntax error\nocamlformat-rpc: ignoring "" (syntax error)\nFile "", line 1, characters 0-1:\nError: Syntax error\nocamlformat-rpc: ignoring "" (syntax error)\nFile "", line 1, characters 0-1:\nError: Syntax error\nocamlformat-rpc: ignoring "" (syntax error)\nFile "", line 2, characters 2-10:\nError: Syntax error\nocamlformat-rpc: ignoring "" (syntax error)\nFile "", line 2, characters 2-10:\nError: Syntax error\n","type":2},"method":"window/logMessage","js

Not sure if the problem is here or somewhere upstream, but wanted to get it down somewhere. Thanks!

versions:
ocaml-lsp-server: 1.17.0
reason-react: 0.14.0
reason-react-ppx: 0.14.0
dune: 3.15.2
melange: 3.0.0-51

[davesnx]

Can you specify the dune and melange versions?

[benbellick]

Edited to include them!

[jchavarri]

It would be helpful if this could be tested with most recent versions of dependencies (using opam update && opam upgrade, might need to upgrade the ocaml compiler manually):

ocaml 5.2
melange 4.0.1-52
reason-react 0.15.0
ocaml-lsp-server 0.19.0

There were some issues with the editor integration that were solved in these versions.

Even with the latest versions, the problem might still happen if it's caused by the externals containing binary information, see related melange-re/melange#749.

[benbellick]

Thanks for the responses.
With the exact versions, the error still persists.

[jsonrpc] (warning) Invalid JSON: (unable to decode byte 0xc0 <callback> 1 156 156) 
...

I believe that that related issue though may be the core of the issue. Thanks