[language-service] getRange does not work for line 0

[ValtsS]

Seems there is a bug here:

The call comes in from doHover(..) if its called on the 1st line - it comes in as line 0. So the for loop never triggers and an invariant error is thrown.

export function getRange(location: SourceLocation, queryText: string): IRange {
  const parser = onlineParser();
  const state = parser.startState();
  const lines = queryText.split('\n');

  invariant(
    lines.length >= location.line,
    'Query text must have more lines than where the error happened',
  );

  let stream = null;

  for (let i = 0; i < location.line; i++) { // Likely should be <=
    stream = new CharacterStream(lines[i]);
    while (!stream.eol()) {
      const style = parser.token(stream, state);
      if (style === 'invalidchar') {
        break;
      }
    }
  }

  invariant(stream, 'Expected Parser stream to be available.');

[acao]

#3149 I believe will fix this?

[acao]

would you say this is a duplicate of #2874?

[ValtsS]

Seems related, but I don't know the code well enough. But I am not sure it would, the call is coming from here

lands here

and we have line 0 while in fact its the 1st line. It might not be 1st token, just fact that it s on 1st line breaks it.

[ValtsS]

Also this part

  invariant(
    lines.length >= location.line,
    'Query text must have more lines than where the error happened',
  );

tells me that the issue is in this function, since invariant expects 0 based line index. Yet it does not work when there is just line 0:

for (let i = 0; i < location.line; i++) { 
...

[acao]

hmm, indeed. if I understand correctly, i think this is why we had to offset lines in packages/monaco-graphql/src/LanguageService.ts, because if I recall, the LSP spec counts lines from 1, whereas monaco counts lines from 0

have you seen this surface as an issue in any specific implementation such as graphiql or monaco-graphql or the LSP server, or are you making a new implementation directly from getHover()?

[ValtsS]

I am using this with monaco

"monaco-editor": "^0.38.0",
"monaco-graphql": "^1.2.2",

As you see the actual query is just 1 liner (incomplete) = "query { }"
So the hover is coming from monaco. There is no custom implementation on my part