I'm not sure what to do with this line. CompletionProvider receives position of '}' of format expression inside of string interpolation. I get previous token for analization, but SpanStart for the token is position - 1. I've temporarily commented this line. @CyrusNajmabadi Do you have any idea what the best way to handle it?

i'm not really understanding the issue. stringTokenOpt should be the appropriate string token for either case, unless the caller isn't passing the right thing.

why were these removed.

IsMethodArgument contains these conditions:

private static bool IsMethodArgument(SyntaxToken token, ISyntaxFacts syntaxFacts)
            => syntaxFacts.IsLiteralExpression(token.Parent) &&
               syntaxFacts.IsArgument(token.Parent!.Parent);

no equivalent change for VB?

why?

To get InterpolatedStringTextToken. For ToString method it returns the same token.

Seems weird. If I was after the token in a format clause, what token is returned?

root.FindToken(position) returns } for $"Text {date:$$}" and for $"Text {date:M$$}"

ok. but what does it return for FindTokenOnLeftOfPosition? i would expect it to return the : token then. Is that not hte case? If FindToken returns the } chec if that's the case (i.e. you're at the start of that token, and move back one token. That seems like the simpler approach to take.

FindTokenOnLeftOfPosition returns : for $"Text {date:$$}" and :M for $"Text {date:$$}". That exactly what we need here.

ok. can you please doc in the code. thanks :)

VB tests?