[css-text-4] Rename `trim-auto` to `trim-both`

[fantasai]

Given the current set of values, and the fact that normal trims adjacent pairs and trim-start indicates trimming the start and adjacent pairs, I think trim-both might be a better name for trim-auto which trims the start, adjacent pairs, and end. Thoughts? CC @MurakamiShinyu @frivoal @kojiishi @myakura

[MurakamiShinyu]

I agree it's better naming trim-both for "trim both start and end".

[frivoal]

trim-auto might not be amazing as a name, but "both" is a strage compoment for something that does 3 things: start, middle, and end. To me, the "auto" part mostly refers to the middle part, as that's what differentiates it from trim-all.

[fantasai]

@frivoal Yeah, but normal and trim-start also do the middle part. The auto-middle part is just baseline behavior at this point.

[MurakamiShinyu]

When I suggested (#4246 (comment)) renaming trim-all (now different thing) to trim-auto, I couldn't think of trim-both because at that time there was no trim-start value and the default included the "trim-end" behavior. But now, after other values changed, trim-both sounds not strange.

[MurakamiShinyu]

This is just an editorial suggestion related on renaming trim-auto to trim-both, I think it would be better to change the order of the value definitions from

<spacing-trim> = space-all | normal | trim-both | trim-start | space-first | trim-all

to

<spacing-trim> = space-all | normal | space-first | trim-start | trim-both | trim-all

(I think this is more natural: space-first is near normal and trim-both is near trim-all)
and the table of the "summary of what the various values do" would be changed to:

Value	Trim at line start	Trim at line end	Trim adjacent pairs	Trim everywhere
space-all	no
normal	no	only if would not fit	yes	no
space-first	yes except on the first line
trim-start	yes
trim-both		yes
trim-all	yes
auto	user-agent specific / platform dependent

With this table, it is much understandable that trim-both means trim at both line start and line end.

[MurakamiShinyu]

The other advantage of the name trim-both is that when the opposite value is needed in the future, the name space-both can be used.

I'm not sure if space-both (space at both line start and line end; trim adjacent pairs) is really needed in CSS, but Adobe InDesign has such a setting in its Mojikumi settings (文字組みアキ量設定), which is called "約物全角" (= "punctuation full-width", but note that adjacent pairs are trimmed).

[css-meeting-bot]

The CSS Working Group just discussed [css-text-4] Rename `trim-auto` to `trim-both` , and agreed to the following:

• RESOLVED: rename trim-auto to trim-both

The full IRC log of that discussion

<TabAtkins> fantasai: text-spacing has a bunch of values.
<TabAtkins> fantasai: as we've tweaked 'normal' and the proeprty syntax, we've gotten to a place where we have "normal" being a baseline behavior where we allow spacing at start/end of th eline, but collapse within the line
<TabAtkins> fantasai: And we have trim-start, trim-all, space-all, space-first
<fantasai> https://github.com//issues/10161#issuecomment-2033649072
<TabAtkins> fantasai: There's also trim-auto which is baseically trim-start + trim-end + the baseline "trim in the middle" behavior
<TabAtkins> fantasai: It makes sense to rename to trim-both, then
<TabAtkins> fantasai: Murakami-san seems to align on that
<TabAtkins> fantasai: I believe this is the one keyword not yet shipped by Chrome, so it should still be fixable
<TabAtkins> proposed resolution: rename trim-auto to trim-both
<TabAtkins> RESOLVED: rename trim-auto to trim-both

[fantasai]

Edited in, thanks @MurakamiShinyu for all of your comments and suggestions!