[css-text] Test text-align: match-parent on the root element

[zcorpan]

If I understand correctly, a used value of 'direction: rtl' on the root element is propagated to the ICB per https://drafts.csswg.org/css-writing-modes-3/#icb

Then, https://drafts.csswg.org/css-text/#valdef-text-align-match-parent says

match-parent
This value behaves the same as inherit (computes to its parent’s computed value) except that an inherited value of start or end is interpreted against the parent’s (or the initial containing block’s, if there is no parent) direction value and results in a computed value of either left or right. When specified on the text-align shorthand, sets both text-align-all and text-align-last to match-parent.

The initial value of text-align is 'start', so I guess the inherited value for the root element has to be 'start'. Therefore, it looks at the 'direction' of the ICB, which is propagated from the root element, and is thus 'rtl'. Therefore text-align should compute to 'right'.

[nt1m]

@zcorpan There's already a test for this: css/css-text/text-align/text-align-match-parent-root-rtl.html

It was in mozilla vendor-imports then was moved to the main test suite.

[nt1m]

Wait, I guess not, this tests the computed style.

[nt1m]

The test name could clarify that it's about the computed value.

[zcorpan]

@nt1m thanks, fixed.

[nt1m]

Maybe this could be named "text-align-match-parent-root-rtl-computed.html" to be consistent with the text-align-match-parent-root-rtl.html test.

Regarding the test that was renamed to "match-parent-001.html", can things be consistent with the rest of the match-parent tests: https://wpt.fyi/results/css/css-text/text-align?label=master&label=experimental&aligned&q=text-align-match-parent- ? The other tests could be renamed.