unicode-org / icu4x / 9401149604

75%

Build Type

push

github

Committed by web-flow

Commit Message

Move LB8a and LB9 out of the table (#5001)

Hopefully no functional change.

Last time I attempted to look at Unicode 15.1 line breaking, that was
made impractical by the need, for every new state X, to add an X_ZWJ
state, transitions X CM → X, X ZWJ → X_ZWJ, X_ZWJ CM → X, as well as
X_ZWJ Y → Z for every transition X Y → Z, and to add or update rules to
prevent breaks after X_ZWJ.

Hopefully this will make that upgrade a little more tractable.
(Incidentally it makes the state table a bit smaller.)

Tested with 200 000 monkeys (recall that only 200 are checked in).

Related to #3255; see my comment there for the rationale.

Aside: While looking at this, it came to my attention that the
`LineBreakStrictness::Anywhere` option does not do what the standard
says, cf.
https://drafts.csswg.org/css-text-3/#valdef-line-break-anywhere and
https://drafts.csswg.org/css-text-3/#typographic-character-unit
referenced therein. Of course, we _do_ have a correct implementation of
`line-break: anywhere`, since we have a grapheme cluster segmenter.

Run Details

14 of 35 new or added lines in 1 file covered. (40.0%)

9 existing lines in 3 files now uncovered.

52797 of 70232 relevant lines covered (75.18%)

564946.71 hits per line