no excessive highlighting

[Johann150]

This should resolve #261.

Is this just okay like this, or should this be configurable?

[brendanzab]

Sorry for my slow review on this - need to figure out whether I'm happy with how we're iterating over the characters of a source line.

[Johann150]

This could also be rewritten using str::rfind, but because we have to find the first trailing non-whitespace character, we would have to find the char lengt of the character to adjust, which makes it not much clearer than the curren solution.

Suggested change

	let text_end = source
	.char_indices()
	.rev()
	.take_while(|(_, c)| c.is_whitespace())
	.last()
	.map(|(index, _)| index)
	.unwrap_or_else(|| source.len());
	let text_end = source
	.rfind(|c| !char::is_whitespace(c))
	.map(|index|
	index + source[index..]
	.chars()
	.next()
	.map_or(0, |c| c.len_utf8())
	)
	.unwrap_or_else(|| source.len());

[Johann150]

@brendanzab any feedback on this?