[css-text-decor-4] Don't skip visible word-separators when skipping only leading/trailing spaces

[fantasai]

text-decoration-skip-spaces allows skipping all spaces, or just leading/trailing spaces. For leading/trailing spaces at least, it probably makes more sense to treat visible word separators as not part of the leading/trailing spaces being skipped.

Relates to w3c/elreq#119

[fantasai]

Hi @r12a, I've redefined the skipped characters to be

• for text-decoration-skip: start || end, any codepoints from general category Zs except U+202F NARROW NO-BREAK SPACE
• for text-decoration-skip: all the above codepoints plus all word separators

Let me know if this seems correct to you or if you think it needs further refinement.

[r12a]

@fantasai i assume you mean text-decoration-skip-spaces rather than text-decoration-skip.

See my comment at w3c/elreq#119 (comment) – basically, i'm starting to wonder whether wordspace needs special treatment, rather than just being treated in the same way as spaces.

It may be simpler to describe what characters are covered by all first, then describe any start|end differences. The main uses so far of NNBSP seem to be for Mongolian MVS and for separating punctuation in languages like French – in these cases i guess NNBSP doesn't appear at a line start/end.