Streamline brace matcher code #73722
Conversation
dotnet-issue-labeler
bot
added
Area-IDE
untriaged
| var text = await document.GetValueTextAsync(cancellationToken).ConfigureAwait(false); | ||
| var trivia = root.FindTrivia(position); |
There was a problem hiding this comment.
it seems like findTrivia is just not that very good. Looking at the impl, it's pretty darn complex. FindToken seems to be much simpler and much more optimized. So changing our code here to just get the token, and walk the start/end trivia of it
There was a problem hiding this comment.
I've never really internalized how structured trivia works.
Nodes can have child nodes/tokens
Tokens have leading/trailing trivia
Trivia may have structure (which is a node)
Can those nodes inside the trivia repeat this cycle?
There was a problem hiding this comment.
Nodes can have child nodes/tokens
Tokens have leading/trailing trivia
Trivia may have structure (which is a node)
100% correct.
Can those nodes inside the trivia repeat this cycle?
No. trivia only goes one more level deep. So within a top levle trivia (like a #if false directive trivia), you have:
- Nodes (the directive trivia, its expressions etc)
- tokens 9the
#,ifandfalsetokens - trivia (the whitespace between those)
However, those final trivia are never structured themselves, so it bottoms out.
We were explicit int he syntax design that no operations go from top level to strucutred trivia automatically, and you always pass the findInsideTrivia flag to control that. And, because there's no more recursion, there's no confusion abuot which level you're diving down into. It's either the top level, or the single structured-trivia level.
Does that make sense?
|
@ToddGrun ptal |
| if (position < token.SpanStart) | ||
| return FindBraces(token.LeadingTrivia); | ||
| else if (position >= token.Span.End) | ||
| return FindBraces(token.TrailingTrivia); | ||
|
|
||
| return null; |
There was a problem hiding this comment.
yeah. this was paranoia.
Drops the cost here to practically nothing:
This is around a goal of getting all tagging work as low as possible.