Resolve single line import expression syntax highlighting #508

[alehechka]

Overview

Partially resolves a-h/templ#508.

I found that the previous begin regex for import-expression would close when it hit the first open curly brace. I updated this regex to instead pattern match @, a function name, open/close parenthesis, then the opening curly brace. This resolved the issue for inline cases.

Additionally, I added an empty-import-expression that only matches against all but the opening curly brace for inline components that are not provided children.

Before

After

However, this does not entirely resolve a-h/templ#508 which specifically asked about multi-line parameters. After reading up on TextMate (which is what VSCode uses under the hood) and finding this issue, it seems that multi-line pattern matching is not natively supported. It does seem possible to nest pattern matching to properly resolve the multi-line params, but I figured this fix was enough for one PR.

I'll likely spend some more time exploring TextMate and see if I can resolve the multi-line param syntax highlighting and can push another PR later.

[a-h]

Thanks for that, much appreciated.