Fix percentage height calculation, absolute containing block height calculations.

It's not possible to correctly determine during the css cascade whether the container height
is explicitly specified. Additionally, the spec https://drafts.csswg.org/css2/visudet.html#the-height-property
says this should affect the *used* height, rather than the computed height.

This significantly improves the layout in #6643.
This commit is contained in:
Glenn Watson 2015-08-03 09:00:46 +10:00
parent ffe4bd25a4
commit b9fea3deb3
10 changed files with 151 additions and 119 deletions

View file

@ -126,29 +126,34 @@ impl MarginCollapseInfo {
pub fn finish_and_compute_collapsible_margins(mut self,
fragment: &Fragment,
containing_block_size: Option<Au>,
can_collapse_block_end_margin_with_kids: bool)
-> (CollapsibleMargins, Au) {
let state = match self.state {
MarginCollapseState::AccumulatingCollapsibleTopMargin => {
match fragment.style().content_block_size() {
LengthOrPercentageOrAuto::Auto | LengthOrPercentageOrAuto::Length(Au(0)) |
LengthOrPercentageOrAuto::Percentage(0.) => {
match fragment.style().min_block_size() {
LengthOrPercentage::Length(Au(0)) | LengthOrPercentage::Percentage(0.) => {
FinalMarginState::MarginsCollapseThrough
},
_ => {
// If the fragment has non-zero min-block-size, margins may not
// collapse through it.
FinalMarginState::BottomMarginCollapses
}
let may_collapse_through = match fragment.style().content_block_size() {
LengthOrPercentageOrAuto::Auto => true,
LengthOrPercentageOrAuto::Length(Au(0)) => true,
LengthOrPercentageOrAuto::Percentage(0.) => true,
LengthOrPercentageOrAuto::Percentage(_) if containing_block_size.is_none() => true,
_ => false,
};
if may_collapse_through {
match fragment.style().min_block_size() {
LengthOrPercentage::Length(Au(0)) | LengthOrPercentage::Percentage(0.) => {
FinalMarginState::MarginsCollapseThrough
},
_ => {
// If the fragment has non-zero min-block-size, margins may not
// collapse through it.
FinalMarginState::BottomMarginCollapses
}
},
_ => {
// If the fragment has an explicitly specified block-size, margins may not
// collapse through it.
FinalMarginState::BottomMarginCollapses
}
} else {
// If the fragment has an explicitly specified block-size, margins may not
// collapse through it.
FinalMarginState::BottomMarginCollapses
}
}
MarginCollapseState::AccumulatingMarginIn => FinalMarginState::BottomMarginCollapses,