Auto merge of #13175 - shinglyu:block-margin-patch, r=notriddle

Move collapse through margin to the top of block flow

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Based on the spec, a collapse through box should be put on the top edge of the flow. This fixed ~110 reftests

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- [x] `./mach build -d` does not report any errors
- [x] `./mach test-tidy` does not report any errors
- [x] These changes fix #12824  (github issue number if applicable).

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- [x] There are tests for these changes OR
- [ ] These changes do not require tests because _____

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This commit is contained in:
bors-servo 2016-09-08 17:43:50 -05:00 committed by GitHub
commit aa011ea275
109 changed files with 21 additions and 324 deletions

View file

@ -895,6 +895,12 @@ impl BlockFlow {
!had_children_with_clearance);
translate_including_floats(&mut cur_b, delta, &mut floats);
// Collapse-through margins should be placed at the top edge,
// so we'll handle the delta after the bottom margin is processed
if let CollapsibleMargins::CollapseThrough(_) = flow::base(kid).collapsible_margins {
cur_b = cur_b - delta;
}
// Clear past the floats that came in, if necessary.
let clearance = match (flow::base(kid).flags.contains(CLEARS_LEFT),
flow::base(kid).flags.contains(CLEARS_RIGHT)) {
@ -926,6 +932,17 @@ impl BlockFlow {
margin_collapse_info.advance_block_end_margin(&kid_base.collapsible_margins);
translate_including_floats(&mut cur_b, delta, &mut floats);
// Collapse-through margin should be placed at the top edge of the flow.
let collapse_delta = match kid_base.collapsible_margins {
CollapsibleMargins::CollapseThrough(_) => {
let delta = margin_collapse_info.current_float_ceiling();
cur_b = cur_b + delta;
kid_base.position.start.b = kid_base.position.start.b + delta;
delta
}
_ => Au(0)
};
if break_at.is_some() {
break
}
@ -938,6 +955,10 @@ impl BlockFlow {
}
ctx.this_fragment_is_empty = false
}
// For consecutive collapse-through flows, their top margin should be calculated
// from the same baseline.
cur_b = cur_b - collapse_delta;
}
// Add in our block-end margin and compute our collapsible margins.