Highlight text pointed to by labels

[dtolnay]

I noticed that codespan-reporting 0.9 is no longer highlighting the file characters pointed to by labels. For my use case I think I found that the highlighted way was preferable. Is this something that you would be open to bringing back as an option?

codespan-reporting 0.8.0:

codespan-reporting 0.9.0:

[jyn514]

Relevant PR: #168

[jyn514]

Maybe #100 and highlighting text could be made mutually exclusive? That would look a little odd visually anyway.

[brendanzab]

Yeah, I'm currently in the process of trying to implement #100, and the highlighted code sections were rather hard to deal with - ie. you need to figure out which to prioiritise (perhaps primary spans?).

As an aside I've also noticed that the diagnostics begin to look super over-bearing when multiline source code is highlighted in colour.

[brendanzab]

Had another look at this today. This is the relevant part of the code that we'd need to change:

codespan/codespan-reporting/src/term/renderer.rs

Lines 268 to 270 in d418193

	// Write source
	write!(self.config.source(self.writer), " {}", source)?;
	write!(self, "\n")?;

Sketching it out, it might look something like this:

// Write source text
write!(self, " ")?;
for (byte_index, ch) in source.char_indices() {
    // TODO: Check if in primary multi-line label
    // TODO: Check if in primary single-line label
    // TODO: Do tab-stop calculation here, rather than using `self.config.source(self.writer)`
    write!(self, "{}", ch)?;
}
// TODO: undo styling if necessary
write!(self, "\n")?;

I'm thinking we'd only highlight primary labels.