Fully implement the "align descendants" rule for div.

This adds -servo-left and -servo-right to complement -servo-center.

This intentionally doesn't try to address issue #7301.
This commit is contained in:
Eli Friedman 2015-10-02 12:53:20 -07:00
parent 0c64e4a2c9
commit 69ca066802
8 changed files with 193 additions and 22 deletions

View file

@ -2470,20 +2470,26 @@ pub trait ISizeAndMarginsComputer {
(MaybeAuto::Specified(margin_start),
MaybeAuto::Specified(inline_size),
MaybeAuto::Specified(margin_end)) => {
match (input.text_align, parent_has_same_direction) {
(text_align::T::servo_center, _) => {
// This is used for `<center>` and friends per HTML5 § 14.3.3. Make the
// inline-start and inline-end margins equal per HTML5 § 14.2.
let margin = (available_inline_size - inline_size).scale_by(0.5);
(margin, inline_size, margin)
}
(_, true) => {
// Ignore the end margin.
// servo_left, servo_right, and servo_center are used to implement
// the "align descendants" rule in HTML5 § 14.2.
// FIXME(#7301): block_align is supposed to be the text-align of the
// parent, not the current node.
let block_align = input.text_align;
if block_align == text_align::T::servo_center {
// Ignore any existing margins, and make the inline-start and
// inline-end margins equal.
let margin = (available_inline_size - inline_size).scale_by(0.5);
(margin, inline_size, margin)
} else {
let ignore_end_margin = match block_align {
text_align::T::servo_left => block_mode.is_bidi_ltr(),
text_align::T::servo_right => !block_mode.is_bidi_ltr(),
_ => parent_has_same_direction,
};
if ignore_end_margin {
(margin_start, inline_size, available_inline_size -
(margin_start + inline_size))
}
(_, false) => {
// Ignore the start margin.
} else {
(available_inline_size - (margin_end + inline_size),
inline_size,
margin_end)

View file

@ -1018,8 +1018,14 @@ impl InlineFlow {
// Translate `left` and `right` to logical directions.
let is_ltr = fragments.fragments[0].style().writing_mode.is_bidi_ltr();
let line_align = match (line_align, is_ltr) {
(text_align::T::left, true) | (text_align::T::right, false) => text_align::T::start,
(text_align::T::left, false) | (text_align::T::right, true) => text_align::T::end,
(text_align::T::left, true) |
(text_align::T::servo_left, true) |
(text_align::T::right, false) |
(text_align::T::servo_right, false) => text_align::T::start,
(text_align::T::left, false) |
(text_align::T::servo_left, false) |
(text_align::T::right, true) |
(text_align::T::servo_right, true) => text_align::T::end,
_ => line_align
};
@ -1039,7 +1045,10 @@ impl InlineFlow {
inline_start_position_for_fragment = inline_start_position_for_fragment +
slack_inline_size
}
text_align::T::left | text_align::T::right => unreachable!()
text_align::T::left |
text_align::T::servo_left |
text_align::T::right |
text_align::T::servo_right => unreachable!()
}
// Lay out the fragments in visual order.