CSS Writing Modes Level 3 Implementation Report

Introduction

CSS Writing Modes Level 3 defines CSS support for various international writing modes, such as left-to-right (e.g. Latin or Indic), right-to-left (e.g. Hebrew or Arabic), bidirectional (e.g. mixed Latin and Arabic) and vertical (e.g. Asian scripts). It has a test suite containing 995 tests. Of those, 866 (87%) meet the CR exit criteria as of January, 2017.

This implementation report examines the remaining tests in more detail. If one filters out tests for the next level of Writing Modes, tests for non-MUST requirements, and tests that require other specifications (all listed in detail below) the test suite contains 879 tests with 865 (98%) meeting the CR exit criteria.

Note that this report counts Blink and WebKit as one implementation, though it shows the data for each where available.

Tests that do not have 2 implementations

1. 4.3. Atomic Inline Baseline: No implementations pass these tests.
   These tests check the synthesized baseline of an inline-block with block descendants.
   • inline-block-alignment-003
   • inline-block-alignment-005
   • inline-block-alignment-007
   • inline-table-alignment-003
   • inline-table-alignment-005
2. 5.1. Orienting Text: the text-orientation property: No implementations pass these tests.
   These tests are for text-orientation: upright defining: This value causes the used value of direction to be ltr, and for the purposes of bidi reordering, causes all characters to be treated as strong LTR.
   • table-progression-vlr-003
   • table-progression-vlr-004
   • table-progression-vrl-003
   • table-progression-vrl-004
3. 7.1: Principles of Layout in Vertical Writing Modes: Only 1 implementation passes these tests.
   3 among the 256 tests for absolute-positioned objects fail. These 256 tests cover combinations of a) direction, b) text-align, c) box offsets (top, left, right, bottom, auto), d) orthogonal and non-orthogonal, and e) ICB.
   • abs-pos-non-replaced-vrl-088
   • abs-pos-non-replaced-vrl-220
   • abs-pos-non-replaced-vrl-224
4. 9. Glyph Composition: Only 1 implementation passes this test. Note that a similar test that has a space character has 2 implementations.
   This test checks when the text inside text-combine-upright has a new line character.
   • text-combine-upright-break-inside-001a

Tests that require other specifications

Following tests do not have 2 implementations, but they require other specifications that they are not considered as required.

Tests that are not MUST

Following tests do not have 2 implementations, but they are defined as MAY/SHOULD and that they are not considered as required.

Tests that were at risk and should move to Level 4

Following tests do not have 2 implementations, but they were at risk in the CR and should move to Level 4 test suites.

All results