Fix #226: Parse quoted blocks with spaces (' {)

[lolgab]

Fixes the linked issue.

[lolgab]

I used [ \\t] instead of \\b because the Scala compiler doesn't accept newlines here.

[nicolasstucki]

A single rule that captures the ' or $ but not rest.

{
  match: "['$](?=[ \\t]*[{[](?!'))"
  name: "..." // not sure what this should be
              // maybe "escape.scala" like in string interpolators
}

[nicolasstucki]

Could also take any space characters

  match: "['$](?=\\s*[{[](?!'))"

[nicolasstucki]

To be more precise

  match: "['$](?=[{[](?!')|\\s+[{[])"

as it is valid to have ${'{...}} even though a warning will be emitted

[lolgab]

Here I added both a tab and a space to cover the handling of tab characters I have in the code.

[tgodzik]

Looks good! We had the same issue recently in Scalameta parser.

[nicolasstucki]

That does not seem right. I believe that the syntax requires the quote to be immediately followed by a curly brace. I will double check.

[tgodzik]

That does not seem right. I believe that the syntax requires the quote to be immediately followed by a curly brace. I will double check.

It doesn't actually. At least last time I checked it did compile with whitespaces :O

[nicolasstucki]

Indeed. I opened an issue to fix this in scala/scala3#13951.

For

' 	{ 2 }
' [ String ]

it looks like the current highlighting is correct for both Scala 2 and Scala 3 (after bug fix) as it is an unclosed Char or a Char with illegal contents.

[lolgab]

Thank you @nicolasstucki for fixing the underlying issue :)

[tgodzik]

@nicolasstucki should we reopen this PR since it turns out it's a correct behaviour?

[lolgab]

I'm reopening since the compiler is not changing behavior.
Still, this change is not perfect because it doesn't parse a comment in the middle of ' and {.

[nicolasstucki]

This is still missing some cases, see and other comments in that thread #227 (comment)

[nicolasstucki]

This was fixed in #250