[ot-shape] Numeric runs native direction is LTR See inline comments. Slightly modified version of the code from Jonathan Kew on the linked issue. Fixes https://github.com/harfbuzz/harfbuzz/issues/501
diff --git a/src/hb-ot-shape.cc b/src/hb-ot-shape.cc index 4fe148d..97958af 100644 --- a/src/hb-ot-shape.cc +++ b/src/hb-ot-shape.cc
@@ -574,6 +574,35 @@ hb_direction_t direction = buffer->props.direction; hb_direction_t horiz_dir = hb_script_get_horizontal_direction (buffer->props.script); + /* Numeric runs in natively-RTL scripts are actually native-LTR, so we reset + * the horiz_dir if the run contains at least one decimal-number char, and no + * letter chars (ideally we should be checking for chars with strong + * directionality but hb-unicode currently lacks bidi categories). + * + * This allows digit sequences in Arabic etc to be shaped in "native" + * direction, so that features like ligatures will work as intended. + * + * https://github.com/harfbuzz/harfbuzz/issues/501 + */ + if (unlikely (horiz_dir == HB_DIRECTION_RTL && direction == HB_DIRECTION_LTR)) + { + bool found_number = false, found_letter = false; + const auto* info = buffer->info; + foreach_grapheme (buffer, start, end) + { + auto gc = _hb_glyph_info_get_general_category (&info[start]); + if (gc == HB_UNICODE_GENERAL_CATEGORY_DECIMAL_NUMBER) + found_number = true; + else if (HB_UNICODE_GENERAL_CATEGORY_IS_LETTER (gc)) + { + found_letter = true; + break; + } + } + if (found_number && !found_letter) + horiz_dir = HB_DIRECTION_LTR; + } + /* TODO vertical: * The only BTT vertical script is Ogham, but it's not clear to me whether OpenType * Ogham fonts are supposed to be implemented BTT or not. Need to research that
diff --git a/src/hb-unicode.hh b/src/hb-unicode.hh index 5c0cb85..0a79944 100644 --- a/src/hb-unicode.hh +++ b/src/hb-unicode.hh
@@ -359,6 +359,13 @@ FLAG (HB_UNICODE_GENERAL_CATEGORY_ENCLOSING_MARK) | \ FLAG (HB_UNICODE_GENERAL_CATEGORY_NON_SPACING_MARK))) +#define HB_UNICODE_GENERAL_CATEGORY_IS_LETTER(gen_cat) \ + (FLAG_UNSAFE (gen_cat) & \ + (FLAG (HB_UNICODE_GENERAL_CATEGORY_LOWERCASE_LETTER) | \ + FLAG (HB_UNICODE_GENERAL_CATEGORY_MODIFIER_LETTER) | \ + FLAG (HB_UNICODE_GENERAL_CATEGORY_OTHER_LETTER) | \ + FLAG (HB_UNICODE_GENERAL_CATEGORY_TITLECASE_LETTER) | \ + FLAG (HB_UNICODE_GENERAL_CATEGORY_UPPERCASE_LETTER))) /* * Ranges, used for bsearch tables.
diff --git a/test/shaping/data/in-house/Makefile.sources b/test/shaping/data/in-house/Makefile.sources index b3fdca2..39cc8d6 100644 --- a/test/shaping/data/in-house/Makefile.sources +++ b/test/shaping/data/in-house/Makefile.sources
@@ -14,6 +14,7 @@ tests/context-matching.tests \ tests/cursive-positioning.tests \ tests/default-ignorables.tests \ + tests/digits.tests \ tests/emoji.tests \ tests/fallback-positioning.tests \ tests/hangul-jamo.tests \
diff --git a/test/shaping/data/in-house/fonts/3b791518a9ba89675df02f1eefbc9026a50648a6.ttf b/test/shaping/data/in-house/fonts/3b791518a9ba89675df02f1eefbc9026a50648a6.ttf new file mode 100644 index 0000000..76855be --- /dev/null +++ b/test/shaping/data/in-house/fonts/3b791518a9ba89675df02f1eefbc9026a50648a6.ttf Binary files differ
diff --git a/test/shaping/data/in-house/fonts/a6b17da98b9f1565ba428719777bbf94a66403c1.ttf b/test/shaping/data/in-house/fonts/a6b17da98b9f1565ba428719777bbf94a66403c1.ttf new file mode 100644 index 0000000..84e8a59 --- /dev/null +++ b/test/shaping/data/in-house/fonts/a6b17da98b9f1565ba428719777bbf94a66403c1.ttf Binary files differ
diff --git a/test/shaping/data/in-house/fonts/b082211be29a3e2cf91f0fd43497e40b2a27b344.ttf b/test/shaping/data/in-house/fonts/b082211be29a3e2cf91f0fd43497e40b2a27b344.ttf new file mode 100644 index 0000000..6e59fd4 --- /dev/null +++ b/test/shaping/data/in-house/fonts/b082211be29a3e2cf91f0fd43497e40b2a27b344.ttf Binary files differ
diff --git a/test/shaping/data/in-house/fonts/e5ff44940364c2247abed50bdda30d2ef5aedfe4.ttf b/test/shaping/data/in-house/fonts/e5ff44940364c2247abed50bdda30d2ef5aedfe4.ttf new file mode 100644 index 0000000..a7c569f --- /dev/null +++ b/test/shaping/data/in-house/fonts/e5ff44940364c2247abed50bdda30d2ef5aedfe4.ttf Binary files differ
diff --git a/test/shaping/data/in-house/meson.build b/test/shaping/data/in-house/meson.build index 0bd1a9d..474a789 100644 --- a/test/shaping/data/in-house/meson.build +++ b/test/shaping/data/in-house/meson.build
@@ -14,6 +14,7 @@ 'context-matching.tests', 'cursive-positioning.tests', 'default-ignorables.tests', + 'digits.tests', 'emoji.tests', 'fallback-positioning.tests', 'hangul-jamo.tests',
diff --git a/test/shaping/data/in-house/tests/digits.tests b/test/shaping/data/in-house/tests/digits.tests new file mode 100644 index 0000000..75f873b --- /dev/null +++ b/test/shaping/data/in-house/tests/digits.tests
@@ -0,0 +1,5 @@ +../fonts/a6b17da98b9f1565ba428719777bbf94a66403c1.ttf:--direction=ltr --script=arab:U+06DD,U+0661,U+0662,U+0663:[uni06DD=0+1279|uni0661.small=1@-1079,0+0|uni0662.small=2@-786,0+0|uni0663.small=3@-493,0+0] +../fonts/e5ff44940364c2247abed50bdda30d2ef5aedfe4.ttf:--direction=ltr --script=arab --features=pnum:U+0661,U+0662,U+0668,U+0663,U+0667:[uni0661.prop=0+361|uni0662.prop=1+436|uni0668.prop=2+478|uni0663.prop=3+597|uni0667.prop=4+527] +../fonts/b082211be29a3e2cf91f0fd43497e40b2a27b344.ttf:--direction=ltr --script=arab:U+06DD,U+0661,U+0662,U+0628:[uni06DD=0+1279|uni0661=1+585|uni0662=2+585|uni0628=3+926] +../fonts/3b791518a9ba89675df02f1eefbc9026a50648a6.ttf:--direction=ltr --script=arab:U+06DD,U+0661,U+0662,U+0663:[AyahEnd.alt3=0+1724|OneArabic.encl=0@-1143,444+0|TwoArabic.encl=0@-864,444+0|ThreeArabic.encl=0@-584,444+0] +../fonts/3b791518a9ba89675df02f1eefbc9026a50648a6.ttf:--direction=rtl --script=arab:U+06DD,U+0661,U+0662,U+0663:[ThreeArabic.encl=0@1140,444+0|TwoArabic.encl=0@860,444+0|OneArabic.encl=0@581,444+0|AyahEnd.alt3=0+1724]