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Diffstat (limited to '')
| -rw-r--r-- | layout/generic/ReflowInput.cpp | 3044 |
1 files changed, 3044 insertions, 0 deletions
diff --git a/layout/generic/ReflowInput.cpp b/layout/generic/ReflowInput.cpp new file mode 100644 index 0000000000..2f91f5f65c --- /dev/null +++ b/layout/generic/ReflowInput.cpp @@ -0,0 +1,3044 @@ +/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */ +/* vim: set ts=8 sts=2 et sw=2 tw=80: */ +/* This Source Code Form is subject to the terms of the Mozilla Public + * License, v. 2.0. If a copy of the MPL was not distributed with this + * file, You can obtain one at http://mozilla.org/MPL/2.0/. */ + +/* struct containing the input to nsIFrame::Reflow */ + +#include "mozilla/ReflowInput.h" + +#include <algorithm> + +#include "CounterStyleManager.h" +#include "LayoutLogging.h" +#include "mozilla/dom/HTMLInputElement.h" +#include "mozilla/StaticPrefs_layout.h" +#include "mozilla/WritingModes.h" +#include "nsBlockFrame.h" +#include "nsCSSAnonBoxes.h" +#include "nsFlexContainerFrame.h" +#include "nsFontInflationData.h" +#include "nsFontMetrics.h" +#include "nsGkAtoms.h" +#include "nsGridContainerFrame.h" +#include "nsIContent.h" +#include "nsIFrame.h" +#include "nsIFrameInlines.h" +#include "nsImageFrame.h" +#include "nsIPercentBSizeObserver.h" +#include "nsLayoutUtils.h" +#include "nsLineBox.h" +#include "nsPresContext.h" +#include "nsStyleConsts.h" +#include "nsTableCellFrame.h" +#include "nsTableFrame.h" +#include "StickyScrollContainer.h" + +using namespace mozilla; +using namespace mozilla::css; +using namespace mozilla::dom; +using namespace mozilla::layout; + +static bool CheckNextInFlowParenthood(nsIFrame* aFrame, nsIFrame* aParent) { + nsIFrame* frameNext = aFrame->GetNextInFlow(); + nsIFrame* parentNext = aParent->GetNextInFlow(); + return frameNext && parentNext && frameNext->GetParent() == parentNext; +} + +/** + * Adjusts the margin for a list (ol, ul), if necessary, depending on + * font inflation settings. Unfortunately, because bullets from a list are + * placed in the margin area, we only have ~40px in which to place the + * bullets. When they are inflated, however, this causes problems, since + * the text takes up more space than is available in the margin. + * + * This method will return a small amount (in app units) by which the + * margin can be adjusted, so that the space is available for list + * bullets to be rendered with font inflation enabled. + */ +static nscoord FontSizeInflationListMarginAdjustment(const nsIFrame* aFrame) { + if (!aFrame->IsBlockFrameOrSubclass()) { + return 0; + } + + // We only want to adjust the margins if we're dealing with an ordered list. + const nsBlockFrame* blockFrame = static_cast<const nsBlockFrame*>(aFrame); + if (!blockFrame->HasMarker()) { + return 0; + } + + float inflation = nsLayoutUtils::FontSizeInflationFor(aFrame); + if (inflation <= 1.0f) { + return 0; + } + + // The HTML spec states that the default padding for ordered lists + // begins at 40px, indicating that we have 40px of space to place a + // bullet. When performing font inflation calculations, we add space + // equivalent to this, but simply inflated at the same amount as the + // text, in app units. + auto margin = nsPresContext::CSSPixelsToAppUnits(40) * (inflation - 1); + + auto* list = aFrame->StyleList(); + if (!list->mCounterStyle.IsAtom()) { + return margin; + } + + nsAtom* type = list->mCounterStyle.AsAtom(); + if (type != nsGkAtoms::none && type != nsGkAtoms::disc && + type != nsGkAtoms::circle && type != nsGkAtoms::square && + type != nsGkAtoms::disclosure_closed && + type != nsGkAtoms::disclosure_open) { + return margin; + } + + return 0; +} + +SizeComputationInput::SizeComputationInput(nsIFrame* aFrame, + gfxContext* aRenderingContext) + : mFrame(aFrame), + mRenderingContext(aRenderingContext), + mWritingMode(aFrame->GetWritingMode()), + mIsThemed(aFrame->IsThemed()), + mComputedMargin(mWritingMode), + mComputedBorderPadding(mWritingMode), + mComputedPadding(mWritingMode) { + MOZ_ASSERT(mFrame); +} + +SizeComputationInput::SizeComputationInput( + nsIFrame* aFrame, gfxContext* aRenderingContext, + WritingMode aContainingBlockWritingMode, nscoord aContainingBlockISize, + const Maybe<LogicalMargin>& aBorder, const Maybe<LogicalMargin>& aPadding) + : SizeComputationInput(aFrame, aRenderingContext) { + MOZ_ASSERT(!mFrame->IsTableColFrame()); + InitOffsets(aContainingBlockWritingMode, aContainingBlockISize, + mFrame->Type(), {}, aBorder, aPadding); +} + +// Initialize a <b>root</b> reflow input with a rendering context to +// use for measuring things. +ReflowInput::ReflowInput(nsPresContext* aPresContext, nsIFrame* aFrame, + gfxContext* aRenderingContext, + const LogicalSize& aAvailableSpace, InitFlags aFlags) + : SizeComputationInput(aFrame, aRenderingContext), + mAvailableSize(aAvailableSpace) { + MOZ_ASSERT(aRenderingContext, "no rendering context"); + MOZ_ASSERT(aPresContext, "no pres context"); + MOZ_ASSERT(aFrame, "no frame"); + MOZ_ASSERT(aPresContext == aFrame->PresContext(), "wrong pres context"); + + if (aFlags.contains(InitFlag::DummyParentReflowInput)) { + mFlags.mDummyParentReflowInput = true; + } + if (aFlags.contains(InitFlag::StaticPosIsCBOrigin)) { + mFlags.mStaticPosIsCBOrigin = true; + } + + if (!aFlags.contains(InitFlag::CallerWillInit)) { + Init(aPresContext); + } + // When we encounter a PageContent frame this will be set to true. + mFlags.mCanHaveClassABreakpoints = false; +} + +// Initialize a reflow input for a child frame's reflow. Some state +// is copied from the parent reflow input; the remaining state is +// computed. +ReflowInput::ReflowInput(nsPresContext* aPresContext, + const ReflowInput& aParentReflowInput, + nsIFrame* aFrame, const LogicalSize& aAvailableSpace, + const Maybe<LogicalSize>& aContainingBlockSize, + InitFlags aFlags, + const StyleSizeOverrides& aSizeOverrides, + ComputeSizeFlags aComputeSizeFlags) + : SizeComputationInput(aFrame, aParentReflowInput.mRenderingContext), + mParentReflowInput(&aParentReflowInput), + mFloatManager(aParentReflowInput.mFloatManager), + mLineLayout(mFrame->IsFrameOfType(nsIFrame::eLineParticipant) + ? aParentReflowInput.mLineLayout + : nullptr), + mBreakType(aParentReflowInput.mBreakType), + mPercentBSizeObserver( + (aParentReflowInput.mPercentBSizeObserver && + aParentReflowInput.mPercentBSizeObserver->NeedsToObserve(*this)) + ? aParentReflowInput.mPercentBSizeObserver + : nullptr), + mFlags(aParentReflowInput.mFlags), + mStyleSizeOverrides(aSizeOverrides), + mComputeSizeFlags(aComputeSizeFlags), + mReflowDepth(aParentReflowInput.mReflowDepth + 1), + mAvailableSize(aAvailableSpace) { + MOZ_ASSERT(aPresContext, "no pres context"); + MOZ_ASSERT(aFrame, "no frame"); + MOZ_ASSERT(aPresContext == aFrame->PresContext(), "wrong pres context"); + MOZ_ASSERT(!mFlags.mSpecialBSizeReflow || !aFrame->IsSubtreeDirty(), + "frame should be clean when getting special bsize reflow"); + + if (mWritingMode.IsOrthogonalTo(aParentReflowInput.GetWritingMode())) { + // If we're setting up for an orthogonal flow, and the parent reflow input + // had a constrained ComputedBSize, we can use that as our AvailableISize + // in preference to leaving it unconstrained. + if (AvailableISize() == NS_UNCONSTRAINEDSIZE && + aParentReflowInput.ComputedBSize() != NS_UNCONSTRAINEDSIZE) { + SetAvailableISize(aParentReflowInput.ComputedBSize()); + } + } + + // Note: mFlags was initialized as a copy of aParentReflowInput.mFlags up in + // this constructor's init list, so the only flags that we need to explicitly + // initialize here are those that may need a value other than our parent's. + mFlags.mNextInFlowUntouched = + aParentReflowInput.mFlags.mNextInFlowUntouched && + CheckNextInFlowParenthood(aFrame, aParentReflowInput.mFrame); + mFlags.mAssumingHScrollbar = mFlags.mAssumingVScrollbar = false; + mFlags.mIsColumnBalancing = false; + mFlags.mColumnSetWrapperHasNoBSizeLeft = false; + mFlags.mTreatBSizeAsIndefinite = false; + mFlags.mDummyParentReflowInput = false; + mFlags.mStaticPosIsCBOrigin = aFlags.contains(InitFlag::StaticPosIsCBOrigin); + mFlags.mIOffsetsNeedCSSAlign = mFlags.mBOffsetsNeedCSSAlign = false; + + // aPresContext->IsPaginated() and the named pages pref should have been + // checked when constructing the root ReflowInput. + if (aParentReflowInput.mFlags.mCanHaveClassABreakpoints) { + MOZ_ASSERT(aPresContext->IsPaginated(), + "mCanHaveClassABreakpoints set during non-paginated reflow."); + } + + { + using mozilla::LayoutFrameType; + switch (mFrame->Type()) { + case LayoutFrameType::PageContent: + // PageContent requires paginated reflow. + MOZ_ASSERT(aPresContext->IsPaginated(), + "nsPageContentFrame should not be in non-paginated reflow"); + MOZ_ASSERT(!mFlags.mCanHaveClassABreakpoints, + "mFlags.mCanHaveClassABreakpoints should have been " + "initalized to false before we found nsPageContentFrame"); + mFlags.mCanHaveClassABreakpoints = true; + break; + case LayoutFrameType::Block: // FALLTHROUGH + case LayoutFrameType::Canvas: // FALLTHROUGH + case LayoutFrameType::FlexContainer: // FALLTHROUGH + case LayoutFrameType::GridContainer: + if (mFrame->HasAnyStateBits(NS_FRAME_OUT_OF_FLOW)) { + // Never allow breakpoints inside of out-of-flow frames. + mFlags.mCanHaveClassABreakpoints = false; + break; + } + // This frame type can have class A breakpoints, inherit this flag + // from the parent (this is done for all flags during construction). + // This also includes Canvas frames, as each PageContent frame always + // has exactly one child which is a Canvas frame. + // Do NOT include the subclasses of BlockFrame here, as the ones for + // which this could be applicable (ColumnSetWrapper and the MathML + // frames) cannot have class A breakpoints. + MOZ_ASSERT(mFlags.mCanHaveClassABreakpoints == + aParentReflowInput.mFlags.mCanHaveClassABreakpoints); + break; + default: + mFlags.mCanHaveClassABreakpoints = false; + break; + } + } + + if (aFlags.contains(InitFlag::DummyParentReflowInput) || + (mParentReflowInput->mFlags.mDummyParentReflowInput && + mFrame->IsTableFrame())) { + mFlags.mDummyParentReflowInput = true; + } + + if (!aFlags.contains(InitFlag::CallerWillInit)) { + Init(aPresContext, aContainingBlockSize); + } +} + +template <typename SizeOrMaxSize> +inline nscoord SizeComputationInput::ComputeISizeValue( + const WritingMode aWM, const LogicalSize& aContainingBlockSize, + const LogicalSize& aContentEdgeToBoxSizing, nscoord aBoxSizingToMarginEdge, + const SizeOrMaxSize& aSize) const { + return mFrame + ->ComputeISizeValue(mRenderingContext, aWM, aContainingBlockSize, + aContentEdgeToBoxSizing, aBoxSizingToMarginEdge, + aSize) + .mISize; +} + +template <typename SizeOrMaxSize> +nscoord SizeComputationInput::ComputeISizeValue( + const LogicalSize& aContainingBlockSize, StyleBoxSizing aBoxSizing, + const SizeOrMaxSize& aSize) const { + WritingMode wm = GetWritingMode(); + const auto borderPadding = ComputedLogicalBorderPadding(wm); + LogicalSize inside = aBoxSizing == StyleBoxSizing::Border + ? borderPadding.Size(wm) + : LogicalSize(wm); + nscoord outside = + borderPadding.IStartEnd(wm) + ComputedLogicalMargin(wm).IStartEnd(wm); + outside -= inside.ISize(wm); + + return ComputeISizeValue(wm, aContainingBlockSize, inside, outside, aSize); +} + +nscoord SizeComputationInput::ComputeBSizeValue( + nscoord aContainingBlockBSize, StyleBoxSizing aBoxSizing, + const LengthPercentage& aSize) const { + WritingMode wm = GetWritingMode(); + nscoord inside = 0; + if (aBoxSizing == StyleBoxSizing::Border) { + inside = ComputedLogicalBorderPadding(wm).BStartEnd(wm); + } + return nsLayoutUtils::ComputeBSizeValue(aContainingBlockBSize, inside, aSize); +} + +bool ReflowInput::ShouldReflowAllKids() const { + // Note that we could make a stronger optimization for IsBResize if + // we use it in a ShouldReflowChild test that replaces the current + // checks of NS_FRAME_IS_DIRTY | NS_FRAME_HAS_DIRTY_CHILDREN, if it + // were tested there along with NS_FRAME_CONTAINS_RELATIVE_BSIZE. + // This would need to be combined with a slight change in which + // frames NS_FRAME_CONTAINS_RELATIVE_BSIZE is marked on. + return mFrame->HasAnyStateBits(NS_FRAME_IS_DIRTY) || IsIResize() || + (IsBResize() && + mFrame->HasAnyStateBits(NS_FRAME_CONTAINS_RELATIVE_BSIZE)); +} + +void ReflowInput::SetComputedISize(nscoord aComputedISize, + ResetResizeFlags aFlags) { + // It'd be nice to assert that |frame| is not in reflow, but this fails + // because viewport frames reset the computed isize on a copy of their reflow + // input when reflowing fixed-pos kids. In that case we actually don't want + // to mess with the resize flags, because comparing the frame's rect to the + // munged computed isize is pointless. + NS_WARNING_ASSERTION(aComputedISize >= 0, "Invalid computed inline-size!"); + if (ComputedISize() != aComputedISize) { + mComputedSize.ISize(mWritingMode) = std::max(0, aComputedISize); + if (aFlags == ResetResizeFlags::Yes) { + InitResizeFlags(mFrame->PresContext(), mFrame->Type()); + } + } +} + +void ReflowInput::SetComputedBSize(nscoord aComputedBSize, + ResetResizeFlags aFlags) { + // It'd be nice to assert that |frame| is not in reflow, but this fails + // for the same reason as above. + NS_WARNING_ASSERTION(aComputedBSize >= 0, "Invalid computed block-size!"); + if (ComputedBSize() != aComputedBSize) { + mComputedSize.BSize(mWritingMode) = std::max(0, aComputedBSize); + InitResizeFlags(mFrame->PresContext(), mFrame->Type()); + } +} + +void ReflowInput::Init(nsPresContext* aPresContext, + const Maybe<LogicalSize>& aContainingBlockSize, + const Maybe<LogicalMargin>& aBorder, + const Maybe<LogicalMargin>& aPadding) { + if (AvailableISize() == NS_UNCONSTRAINEDSIZE) { + // Look up the parent chain for an orthogonal inline limit, + // and reset AvailableISize() if found. + for (const ReflowInput* parent = mParentReflowInput; parent != nullptr; + parent = parent->mParentReflowInput) { + if (parent->GetWritingMode().IsOrthogonalTo(mWritingMode) && + parent->mOrthogonalLimit != NS_UNCONSTRAINEDSIZE) { + SetAvailableISize(parent->mOrthogonalLimit); + break; + } + } + } + + LAYOUT_WARN_IF_FALSE(AvailableISize() != NS_UNCONSTRAINEDSIZE, + "have unconstrained inline-size; this should only " + "result from very large sizes, not attempts at " + "intrinsic inline-size calculation"); + + mStylePosition = mFrame->StylePosition(); + mStyleDisplay = mFrame->StyleDisplay(); + mStyleBorder = mFrame->StyleBorder(); + mStyleMargin = mFrame->StyleMargin(); + + InitCBReflowInput(); + + LayoutFrameType type = mFrame->Type(); + if (type == mozilla::LayoutFrameType::Placeholder) { + // Placeholders have a no-op Reflow method that doesn't need the rest of + // this initialization, so we bail out early. + mComputedSize.SizeTo(mWritingMode, 0, 0); + return; + } + + mFlags.mIsReplaced = mFrame->IsFrameOfType(nsIFrame::eReplaced) || + mFrame->IsFrameOfType(nsIFrame::eReplacedContainsBlock); + + InitConstraints(aPresContext, aContainingBlockSize, aBorder, aPadding, type); + + InitResizeFlags(aPresContext, type); + InitDynamicReflowRoot(); + + nsIFrame* parent = mFrame->GetParent(); + if (parent && parent->HasAnyStateBits(NS_FRAME_IN_CONSTRAINED_BSIZE) && + !(parent->IsScrollFrame() && + parent->StyleDisplay()->mOverflowY != StyleOverflow::Hidden)) { + mFrame->AddStateBits(NS_FRAME_IN_CONSTRAINED_BSIZE); + } else if (type == LayoutFrameType::SVGForeignObject) { + // An SVG foreignObject frame is inherently constrained block-size. + mFrame->AddStateBits(NS_FRAME_IN_CONSTRAINED_BSIZE); + } else { + const auto& bSizeCoord = mStylePosition->BSize(mWritingMode); + const auto& maxBSizeCoord = mStylePosition->MaxBSize(mWritingMode); + if ((!bSizeCoord.BehavesLikeInitialValueOnBlockAxis() || + !maxBSizeCoord.BehavesLikeInitialValueOnBlockAxis()) && + // Don't set NS_FRAME_IN_CONSTRAINED_BSIZE on body or html elements. + (mFrame->GetContent() && !(mFrame->GetContent()->IsAnyOfHTMLElements( + nsGkAtoms::body, nsGkAtoms::html)))) { + // If our block-size was specified as a percentage, then this could + // actually resolve to 'auto', based on: + // http://www.w3.org/TR/CSS21/visudet.html#the-height-property + nsIFrame* containingBlk = mFrame; + while (containingBlk) { + const nsStylePosition* stylePos = containingBlk->StylePosition(); + const auto& bSizeCoord = stylePos->BSize(mWritingMode); + const auto& maxBSizeCoord = stylePos->MaxBSize(mWritingMode); + if ((bSizeCoord.IsLengthPercentage() && !bSizeCoord.HasPercent()) || + (maxBSizeCoord.IsLengthPercentage() && + !maxBSizeCoord.HasPercent())) { + mFrame->AddStateBits(NS_FRAME_IN_CONSTRAINED_BSIZE); + break; + } else if (bSizeCoord.HasPercent() || maxBSizeCoord.HasPercent()) { + if (!(containingBlk = containingBlk->GetContainingBlock())) { + // If we've reached the top of the tree, then we don't have + // a constrained block-size. + mFrame->RemoveStateBits(NS_FRAME_IN_CONSTRAINED_BSIZE); + break; + } + + continue; + } else { + mFrame->RemoveStateBits(NS_FRAME_IN_CONSTRAINED_BSIZE); + break; + } + } + } else { + mFrame->RemoveStateBits(NS_FRAME_IN_CONSTRAINED_BSIZE); + } + } + + if (mParentReflowInput && + mParentReflowInput->GetWritingMode().IsOrthogonalTo(mWritingMode)) { + // Orthogonal frames are always reflowed with an unconstrained + // dimension to avoid incomplete reflow across an orthogonal + // boundary. Normally this is the block-size, but for column sets + // with auto-height it's the inline-size, so that they can add + // columns in the container's block direction + if (type == LayoutFrameType::ColumnSet && + mStylePosition->ISize(mWritingMode).IsAuto()) { + SetComputedISize(NS_UNCONSTRAINEDSIZE, ResetResizeFlags::No); + } else { + SetAvailableBSize(NS_UNCONSTRAINEDSIZE); + } + } + + if (mFrame->GetContainSizeAxes().mBContained) { + // In the case that a box is size contained in block axis, we want to ensure + // that it is also monolithic. We do this by setting AvailableBSize() to an + // unconstrained size to avoid fragmentation. + SetAvailableBSize(NS_UNCONSTRAINEDSIZE); + } + + LAYOUT_WARN_IF_FALSE((mStyleDisplay->IsInlineOutsideStyle() && + !mFrame->IsFrameOfType(nsIFrame::eReplaced)) || + type == LayoutFrameType::Text || + ComputedISize() != NS_UNCONSTRAINEDSIZE, + "have unconstrained inline-size; this should only " + "result from very large sizes, not attempts at " + "intrinsic inline-size calculation"); +} + +static bool MightBeContainingBlockFor(nsIFrame* aMaybeContainingBlock, + nsIFrame* aFrame, + const nsStyleDisplay* aStyleDisplay) { + // Keep this in sync with nsIFrame::GetContainingBlock. + if (aFrame->IsAbsolutelyPositioned(aStyleDisplay) && + aMaybeContainingBlock == aFrame->GetParent()) { + return true; + } + return aMaybeContainingBlock->IsBlockContainer(); +} + +void ReflowInput::InitCBReflowInput() { + if (!mParentReflowInput) { + mCBReflowInput = nullptr; + return; + } + if (mParentReflowInput->mFlags.mDummyParentReflowInput) { + mCBReflowInput = mParentReflowInput; + return; + } + + // To avoid a long walk up the frame tree check if the parent frame can be a + // containing block for mFrame. + if (MightBeContainingBlockFor(mParentReflowInput->mFrame, mFrame, + mStyleDisplay) && + mParentReflowInput->mFrame == + mFrame->GetContainingBlock(0, mStyleDisplay)) { + // Inner table frames need to use the containing block of the outer + // table frame. + if (mFrame->IsTableFrame()) { + mCBReflowInput = mParentReflowInput->mCBReflowInput; + } else { + mCBReflowInput = mParentReflowInput; + } + } else { + mCBReflowInput = mParentReflowInput->mCBReflowInput; + } +} + +/* Check whether CalcQuirkContainingBlockHeight would stop on the + * given reflow input, using its block as a height. (essentially + * returns false for any case in which CalcQuirkContainingBlockHeight + * has a "continue" in its main loop.) + * + * XXX Maybe refactor CalcQuirkContainingBlockHeight so it uses + * this function as well + */ +static bool IsQuirkContainingBlockHeight(const ReflowInput* rs, + LayoutFrameType aFrameType) { + if (LayoutFrameType::Block == aFrameType || + LayoutFrameType::Scroll == aFrameType) { + // Note: This next condition could change due to a style change, + // but that would cause a style reflow anyway, which means we're ok. + if (NS_UNCONSTRAINEDSIZE == rs->ComputedHeight()) { + if (!rs->mFrame->IsAbsolutelyPositioned(rs->mStyleDisplay)) { + return false; + } + } + } + return true; +} + +void ReflowInput::InitResizeFlags(nsPresContext* aPresContext, + LayoutFrameType aFrameType) { + SetBResize(false); + SetIResize(false); + mFlags.mIsBResizeForPercentages = false; + + const WritingMode wm = mWritingMode; // just a shorthand + // We should report that we have a resize in the inline dimension if + // *either* the border-box size or the content-box size in that + // dimension has changed. It might not actually be necessary to do + // this if the border-box size has changed and the content-box size + // has not changed, but since we've historically used the flag to mean + // border-box size change, continue to do that. It's possible for + // the content-box size to change without a border-box size change or + // a style change given (1) a fixed width (possibly fixed by max-width + // or min-width), box-sizing:border-box, and percentage padding; + // (2) box-sizing:content-box, M% width, and calc(Npx - M%) padding. + // + // However, we don't actually have the information at this point to tell + // whether the content-box size has changed, since both style data and the + // UsedPaddingProperty() have already been updated in + // SizeComputationInput::InitOffsets(). So, we check the HasPaddingChange() + // bit for the cases where it's possible for the content-box size to have + // changed without either (a) a change in the border-box size or (b) an + // nsChangeHint_NeedDirtyReflow change hint due to change in border or + // padding. + // + // We don't clear the HasPaddingChange() bit here, since sometimes we + // construct reflow input (e.g. in nsBlockFrame::ReflowBlockFrame to compute + // margin collapsing) without reflowing the frame. Instead, we clear it in + // nsIFrame::DidReflow(). + bool isIResize = + // is the border-box resizing? + mFrame->ISize(wm) != + ComputedISize() + ComputedLogicalBorderPadding(wm).IStartEnd(wm) || + // or is the content-box resizing? (see comment above) + mFrame->HasPaddingChange(); + + if (mFrame->HasAnyStateBits(NS_FRAME_FONT_INFLATION_FLOW_ROOT) && + nsLayoutUtils::FontSizeInflationEnabled(aPresContext)) { + // Create our font inflation data if we don't have it already, and + // give it our current width information. + bool dirty = nsFontInflationData::UpdateFontInflationDataISizeFor(*this) && + // Avoid running this at the box-to-block interface + // (where we shouldn't be inflating anyway, and where + // reflow input construction is probably to construct a + // dummy parent reflow input anyway). + !mFlags.mDummyParentReflowInput; + + if (dirty || (!mFrame->GetParent() && isIResize)) { + // When font size inflation is enabled, a change in either: + // * the effective width of a font inflation flow root + // * the width of the frame + // needs to cause a dirty reflow since they change the font size + // inflation calculations, which in turn change the size of text, + // line-heights, etc. This is relatively similar to a classic + // case of style change reflow, except that because inflation + // doesn't affect the intrinsic sizing codepath, there's no need + // to invalidate intrinsic sizes. + // + // Note that this makes horizontal resizing a good bit more + // expensive. However, font size inflation is targeted at a set of + // devices (zoom-and-pan devices) where the main use case for + // horizontal resizing needing to be efficient (window resizing) is + // not present. It does still increase the cost of dynamic changes + // caused by script where a style or content change in one place + // causes a resize in another (e.g., rebalancing a table). + + // FIXME: This isn't so great for the cases where + // ReflowInput::SetComputedWidth is called, if the first time + // we go through InitResizeFlags we set IsHResize() to true, and then + // the second time we'd set it to false even without the + // NS_FRAME_IS_DIRTY bit already set. + if (mFrame->IsSVGForeignObjectFrame()) { + // Foreign object frames use dirty bits in a special way. + mFrame->AddStateBits(NS_FRAME_HAS_DIRTY_CHILDREN); + nsIFrame* kid = mFrame->PrincipalChildList().FirstChild(); + if (kid) { + kid->MarkSubtreeDirty(); + } + } else { + mFrame->MarkSubtreeDirty(); + } + + // Mark intrinsic widths on all descendants dirty. We need to do + // this (1) since we're changing the size of text and need to + // clear text runs on text frames and (2) since we actually are + // changing some intrinsic widths, but only those that live inside + // of containers. + + // It makes sense to do this for descendants but not ancestors + // (which is unusual) because we're only changing the unusual + // inflation-dependent intrinsic widths (i.e., ones computed with + // nsPresContext::mInflationDisabledForShrinkWrap set to false), + // which should never affect anything outside of their inflation + // flow root (or, for that matter, even their inflation + // container). + + // This is also different from what PresShell::FrameNeedsReflow + // does because it doesn't go through placeholders. It doesn't + // need to because we're actually doing something that cares about + // frame tree geometry (the width on an ancestor) rather than + // style. + + AutoTArray<nsIFrame*, 32> stack; + stack.AppendElement(mFrame); + + do { + nsIFrame* f = stack.PopLastElement(); + for (const auto& childList : f->ChildLists()) { + for (nsIFrame* kid : childList.mList) { + kid->MarkIntrinsicISizesDirty(); + stack.AppendElement(kid); + } + } + } while (stack.Length() != 0); + } + } + + SetIResize(!mFrame->HasAnyStateBits(NS_FRAME_IS_DIRTY) && isIResize); + + // XXX Should we really need to null check mCBReflowInput? (We do for + // at least nsBoxFrame). + if (mFrame->HasBSizeChange()) { + // When we have an nsChangeHint_UpdateComputedBSize, we'll set a bit + // on the frame to indicate we're resizing. This might catch cases, + // such as a change between auto and a length, where the box doesn't + // actually resize but children with percentages resize (since those + // percentages become auto if their containing block is auto). + SetBResize(true); + mFlags.mIsBResizeForPercentages = true; + // We don't clear the HasBSizeChange state here, since sometimes we + // construct a ReflowInput (e.g. in nsBlockFrame::ReflowBlockFrame to + // compute margin collapsing) without reflowing the frame. Instead, we + // clear it in nsIFrame::DidReflow. + } else if (mCBReflowInput && + mCBReflowInput->IsBResizeForPercentagesForWM(wm) && + (mStylePosition->BSize(wm).HasPercent() || + mStylePosition->MinBSize(wm).HasPercent() || + mStylePosition->MaxBSize(wm).HasPercent())) { + // We have a percentage (or calc-with-percentage) block-size, and the + // value it's relative to has changed. + SetBResize(true); + mFlags.mIsBResizeForPercentages = true; + } else if (aFrameType == LayoutFrameType::TableCell && + (mFlags.mSpecialBSizeReflow || + mFrame->FirstInFlow()->HasAnyStateBits( + NS_TABLE_CELL_HAD_SPECIAL_REFLOW)) && + mFrame->HasAnyStateBits(NS_FRAME_CONTAINS_RELATIVE_BSIZE)) { + // Need to set the bit on the cell so that + // mCBReflowInput->IsBResize() is set correctly below when + // reflowing descendant. + SetBResize(true); + mFlags.mIsBResizeForPercentages = true; + } else if (mCBReflowInput && mFrame->IsBlockWrapper()) { + // XXX Is this problematic for relatively positioned inlines acting + // as containing block for absolutely positioned elements? + // Possibly; in that case we should at least be checking + // IsSubtreeDirty(), I'd think. + SetBResize(mCBReflowInput->IsBResizeForWM(wm)); + mFlags.mIsBResizeForPercentages = + mCBReflowInput->IsBResizeForPercentagesForWM(wm); + } else if (ComputedBSize() == NS_UNCONSTRAINEDSIZE) { + // We have an 'auto' block-size. + if (eCompatibility_NavQuirks == aPresContext->CompatibilityMode() && + mCBReflowInput) { + // FIXME: This should probably also check IsIResize(). + SetBResize(mCBReflowInput->IsBResizeForWM(wm)); + } else { + SetBResize(IsIResize()); + } + SetBResize(IsBResize() || mFrame->IsSubtreeDirty()); + } else { + // We have a non-'auto' block-size, i.e., a length. Set the BResize + // flag to whether the size is actually different. + SetBResize(mFrame->BSize(wm) != + ComputedBSize() + + ComputedLogicalBorderPadding(wm).BStartEnd(wm)); + } + + bool dependsOnCBBSize = (mStylePosition->BSizeDependsOnContainer(wm) && + // FIXME: condition this on not-abspos? + !mStylePosition->BSize(wm).IsAuto()) || + mStylePosition->MinBSizeDependsOnContainer(wm) || + mStylePosition->MaxBSizeDependsOnContainer(wm) || + mStylePosition->mOffset.GetBStart(wm).HasPercent() || + !mStylePosition->mOffset.GetBEnd(wm).IsAuto(); + + // If mFrame is a flex item, and mFrame's block axis is the flex container's + // main axis (e.g. in a column-oriented flex container with same + // writing-mode), then its block-size depends on its CB size, if its + // flex-basis has a percentage. + if (mFrame->IsFlexItem() && + !nsFlexContainerFrame::IsItemInlineAxisMainAxis(mFrame)) { + const auto& flexBasis = mStylePosition->mFlexBasis; + dependsOnCBBSize |= (flexBasis.IsSize() && flexBasis.AsSize().HasPercent()); + } + + if (mFrame->StyleText()->mLineHeight.IsMozBlockHeight()) { + // line-height depends on block bsize + mFrame->AddStateBits(NS_FRAME_CONTAINS_RELATIVE_BSIZE); + // but only on containing blocks if this frame is not a suitable block + dependsOnCBBSize |= !nsLayoutUtils::IsNonWrapperBlock(mFrame); + } + + // If we're the descendant of a table cell that performs special bsize + // reflows and we could be the child that requires them, always set + // the block-axis resize in case this is the first pass before the + // special bsize reflow. However, don't do this if it actually is + // the special bsize reflow, since in that case it will already be + // set correctly above if we need it set. + if (!IsBResize() && mCBReflowInput && + (mCBReflowInput->mFrame->IsTableCellFrame() || + mCBReflowInput->mFlags.mHeightDependsOnAncestorCell) && + !mCBReflowInput->mFlags.mSpecialBSizeReflow && dependsOnCBBSize) { + SetBResize(true); + mFlags.mHeightDependsOnAncestorCell = true; + } + + // Set NS_FRAME_CONTAINS_RELATIVE_BSIZE if it's needed. + + // It would be nice to check that |ComputedBSize != NS_UNCONSTRAINEDSIZE| + // &&ed with the percentage bsize check. However, this doesn't get + // along with table special bsize reflows, since a special bsize + // reflow (a quirk that makes such percentage height work on children + // of table cells) can cause not just a single percentage height to + // become fixed, but an entire descendant chain of percentage height + // to become fixed. + if (dependsOnCBBSize && mCBReflowInput) { + const ReflowInput* rs = this; + bool hitCBReflowInput = false; + do { + rs = rs->mParentReflowInput; + if (!rs) { + break; + } + + if (rs->mFrame->HasAnyStateBits(NS_FRAME_CONTAINS_RELATIVE_BSIZE)) { + break; // no need to go further + } + rs->mFrame->AddStateBits(NS_FRAME_CONTAINS_RELATIVE_BSIZE); + + // Keep track of whether we've hit the containing block, because + // we need to go at least that far. + if (rs == mCBReflowInput) { + hitCBReflowInput = true; + } + + // XXX What about orthogonal flows? It doesn't make sense to + // keep propagating this bit across an orthogonal boundary, + // where the meaning of BSize changes. Bug 1175517. + } while (!hitCBReflowInput || + (eCompatibility_NavQuirks == aPresContext->CompatibilityMode() && + !IsQuirkContainingBlockHeight(rs, rs->mFrame->Type()))); + // Note: We actually don't need to set the + // NS_FRAME_CONTAINS_RELATIVE_BSIZE bit for the cases + // where we hit the early break statements in + // CalcQuirkContainingBlockHeight. But it doesn't hurt + // us to set the bit in these cases. + } + if (mFrame->HasAnyStateBits(NS_FRAME_IS_DIRTY)) { + // If we're reflowing everything, then we'll find out if we need + // to re-set this. + mFrame->RemoveStateBits(NS_FRAME_CONTAINS_RELATIVE_BSIZE); + } +} + +void ReflowInput::InitDynamicReflowRoot() { + if (mFrame->CanBeDynamicReflowRoot()) { + mFrame->AddStateBits(NS_FRAME_DYNAMIC_REFLOW_ROOT); + } else { + mFrame->RemoveStateBits(NS_FRAME_DYNAMIC_REFLOW_ROOT); + } +} + +bool ReflowInput::ShouldApplyAutomaticMinimumOnBlockAxis() const { + MOZ_ASSERT(!mFrame->IsFrameOfType(nsIFrame::eReplacedSizing)); + return mFlags.mIsBSizeSetByAspectRatio && + !mStyleDisplay->IsScrollableOverflow() && + mStylePosition->MinBSize(GetWritingMode()).IsAuto(); +} + +bool ReflowInput::IsInFragmentedContext() const { + // We consider mFrame with a prev-in-flow being in a fragmented context + // because nsColumnSetFrame can reflow its last column with an unconstrained + // available block-size. + return AvailableBSize() != NS_UNCONSTRAINEDSIZE || mFrame->GetPrevInFlow(); +} + +/* static */ +LogicalMargin ReflowInput::ComputeRelativeOffsets(WritingMode aWM, + nsIFrame* aFrame, + const LogicalSize& aCBSize) { + LogicalMargin offsets(aWM); + const nsStylePosition* position = aFrame->StylePosition(); + + // Compute the 'inlineStart' and 'inlineEnd' values. 'inlineStart' + // moves the boxes to the end of the line, and 'inlineEnd' moves the + // boxes to the start of the line. The computed values are always: + // inlineStart=-inlineEnd + const auto& inlineStart = position->mOffset.GetIStart(aWM); + const auto& inlineEnd = position->mOffset.GetIEnd(aWM); + bool inlineStartIsAuto = inlineStart.IsAuto(); + bool inlineEndIsAuto = inlineEnd.IsAuto(); + + // If neither 'inlineStart' nor 'inlineEnd' is auto, then we're + // over-constrained and we ignore one of them + if (!inlineStartIsAuto && !inlineEndIsAuto) { + inlineEndIsAuto = true; + } + + if (inlineStartIsAuto) { + if (inlineEndIsAuto) { + // If both are 'auto' (their initial values), the computed values are 0 + offsets.IStart(aWM) = offsets.IEnd(aWM) = 0; + } else { + // 'inlineEnd' isn't 'auto' so compute its value + offsets.IEnd(aWM) = + nsLayoutUtils::ComputeCBDependentValue(aCBSize.ISize(aWM), inlineEnd); + + // Computed value for 'inlineStart' is minus the value of 'inlineEnd' + offsets.IStart(aWM) = -offsets.IEnd(aWM); + } + + } else { + NS_ASSERTION(inlineEndIsAuto, "unexpected specified constraint"); + + // 'InlineStart' isn't 'auto' so compute its value + offsets.IStart(aWM) = + nsLayoutUtils::ComputeCBDependentValue(aCBSize.ISize(aWM), inlineStart); + + // Computed value for 'inlineEnd' is minus the value of 'inlineStart' + offsets.IEnd(aWM) = -offsets.IStart(aWM); + } + + // Compute the 'blockStart' and 'blockEnd' values. The 'blockStart' + // and 'blockEnd' properties move relatively positioned elements in + // the block progression direction. They also must be each other's + // negative + const auto& blockStart = position->mOffset.GetBStart(aWM); + const auto& blockEnd = position->mOffset.GetBEnd(aWM); + bool blockStartIsAuto = blockStart.IsAuto(); + bool blockEndIsAuto = blockEnd.IsAuto(); + + // Check for percentage based values and a containing block block-size + // that depends on the content block-size. Treat them like 'auto' + if (NS_UNCONSTRAINEDSIZE == aCBSize.BSize(aWM)) { + if (blockStart.HasPercent()) { + blockStartIsAuto = true; + } + if (blockEnd.HasPercent()) { + blockEndIsAuto = true; + } + } + + // If neither is 'auto', 'block-end' is ignored + if (!blockStartIsAuto && !blockEndIsAuto) { + blockEndIsAuto = true; + } + + if (blockStartIsAuto) { + if (blockEndIsAuto) { + // If both are 'auto' (their initial values), the computed values are 0 + offsets.BStart(aWM) = offsets.BEnd(aWM) = 0; + } else { + // 'blockEnd' isn't 'auto' so compute its value + offsets.BEnd(aWM) = nsLayoutUtils::ComputeBSizeDependentValue( + aCBSize.BSize(aWM), blockEnd); + + // Computed value for 'blockStart' is minus the value of 'blockEnd' + offsets.BStart(aWM) = -offsets.BEnd(aWM); + } + + } else { + NS_ASSERTION(blockEndIsAuto, "unexpected specified constraint"); + + // 'blockStart' isn't 'auto' so compute its value + offsets.BStart(aWM) = nsLayoutUtils::ComputeBSizeDependentValue( + aCBSize.BSize(aWM), blockStart); + + // Computed value for 'blockEnd' is minus the value of 'blockStart' + offsets.BEnd(aWM) = -offsets.BStart(aWM); + } + + // Convert the offsets to physical coordinates and store them on the frame + const nsMargin physicalOffsets = offsets.GetPhysicalMargin(aWM); + if (nsMargin* prop = + aFrame->GetProperty(nsIFrame::ComputedOffsetProperty())) { + *prop = physicalOffsets; + } else { + aFrame->AddProperty(nsIFrame::ComputedOffsetProperty(), + new nsMargin(physicalOffsets)); + } + + NS_ASSERTION(offsets.IStart(aWM) == -offsets.IEnd(aWM) && + offsets.BStart(aWM) == -offsets.BEnd(aWM), + "ComputeRelativeOffsets should return valid results!"); + + return offsets; +} + +/* static */ +void ReflowInput::ApplyRelativePositioning(nsIFrame* aFrame, + const nsMargin& aComputedOffsets, + nsPoint* aPosition) { + if (!aFrame->IsRelativelyOrStickyPositioned()) { + NS_ASSERTION(!aFrame->HasProperty(nsIFrame::NormalPositionProperty()), + "We assume that changing the 'position' property causes " + "frame reconstruction. If that ever changes, this code " + "should call " + "aFrame->RemoveProperty(nsIFrame::NormalPositionProperty())"); + return; + } + + // Store the normal position + aFrame->SetProperty(nsIFrame::NormalPositionProperty(), *aPosition); + + const nsStyleDisplay* display = aFrame->StyleDisplay(); + if (StylePositionProperty::Relative == display->mPosition) { + *aPosition += nsPoint(aComputedOffsets.left, aComputedOffsets.top); + } else if (StylePositionProperty::Sticky == display->mPosition && + !aFrame->GetNextContinuation() && !aFrame->GetPrevContinuation() && + !aFrame->HasAnyStateBits(NS_FRAME_PART_OF_IBSPLIT)) { + // Sticky positioning for elements with multiple frames needs to be + // computed all at once. We can't safely do that here because we might be + // partway through (re)positioning the frames, so leave it until the scroll + // container reflows and calls StickyScrollContainer::UpdatePositions. + // For single-frame sticky positioned elements, though, go ahead and apply + // it now to avoid unnecessary overflow updates later. + StickyScrollContainer* ssc = + StickyScrollContainer::GetStickyScrollContainerForFrame(aFrame); + if (ssc) { + *aPosition = ssc->ComputePosition(aFrame); + } + } +} + +// static +void ReflowInput::ComputeAbsPosInlineAutoMargin(nscoord aAvailMarginSpace, + WritingMode aContainingBlockWM, + bool aIsMarginIStartAuto, + bool aIsMarginIEndAuto, + LogicalMargin& aMargin, + LogicalMargin& aOffsets) { + if (aIsMarginIStartAuto) { + if (aIsMarginIEndAuto) { + if (aAvailMarginSpace < 0) { + // Note that this case is different from the neither-'auto' + // case below, where the spec says to ignore 'left'/'right'. + // Ignore the specified value for 'margin-right'. + aMargin.IEnd(aContainingBlockWM) = aAvailMarginSpace; + } else { + // Both 'margin-left' and 'margin-right' are 'auto', so they get + // equal values + aMargin.IStart(aContainingBlockWM) = aAvailMarginSpace / 2; + aMargin.IEnd(aContainingBlockWM) = + aAvailMarginSpace - aMargin.IStart(aContainingBlockWM); + } + } else { + // Just 'margin-left' is 'auto' + aMargin.IStart(aContainingBlockWM) = aAvailMarginSpace; + } + } else { + if (aIsMarginIEndAuto) { + // Just 'margin-right' is 'auto' + aMargin.IEnd(aContainingBlockWM) = aAvailMarginSpace; + } else { + // We're over-constrained so use the direction of the containing + // block to dictate which value to ignore. (And note that the + // spec says to ignore 'left' or 'right' rather than + // 'margin-left' or 'margin-right'.) + // Note that this case is different from the both-'auto' case + // above, where the spec says to ignore + // 'margin-left'/'margin-right'. + // Ignore the specified value for 'right'. + aOffsets.IEnd(aContainingBlockWM) += aAvailMarginSpace; + } + } +} + +// static +void ReflowInput::ComputeAbsPosBlockAutoMargin(nscoord aAvailMarginSpace, + WritingMode aContainingBlockWM, + bool aIsMarginBStartAuto, + bool aIsMarginBEndAuto, + LogicalMargin& aMargin, + LogicalMargin& aOffsets) { + if (aIsMarginBStartAuto) { + if (aIsMarginBEndAuto) { + // Both 'margin-top' and 'margin-bottom' are 'auto', so they get + // equal values + aMargin.BStart(aContainingBlockWM) = aAvailMarginSpace / 2; + aMargin.BEnd(aContainingBlockWM) = + aAvailMarginSpace - aMargin.BStart(aContainingBlockWM); + } else { + // Just margin-block-start is 'auto' + aMargin.BStart(aContainingBlockWM) = aAvailMarginSpace; + } + } else { + if (aIsMarginBEndAuto) { + // Just margin-block-end is 'auto' + aMargin.BEnd(aContainingBlockWM) = aAvailMarginSpace; + } else { + // We're over-constrained so ignore the specified value for + // block-end. (And note that the spec says to ignore 'bottom' + // rather than 'margin-bottom'.) + aOffsets.BEnd(aContainingBlockWM) += aAvailMarginSpace; + } + } +} + +void ReflowInput::ApplyRelativePositioning( + nsIFrame* aFrame, mozilla::WritingMode aWritingMode, + const mozilla::LogicalMargin& aComputedOffsets, + mozilla::LogicalPoint* aPosition, const nsSize& aContainerSize) { + // Subtract the size of the frame from the container size that we + // use for converting between the logical and physical origins of + // the frame. This accounts for the fact that logical origins in RTL + // coordinate systems are at the top right of the frame instead of + // the top left. + nsSize frameSize = aFrame->GetSize(); + nsPoint pos = + aPosition->GetPhysicalPoint(aWritingMode, aContainerSize - frameSize); + ApplyRelativePositioning( + aFrame, aComputedOffsets.GetPhysicalMargin(aWritingMode), &pos); + *aPosition = + mozilla::LogicalPoint(aWritingMode, pos, aContainerSize - frameSize); +} + +nsIFrame* ReflowInput::GetHypotheticalBoxContainer(nsIFrame* aFrame, + nscoord& aCBIStartEdge, + LogicalSize& aCBSize) const { + aFrame = aFrame->GetContainingBlock(); + NS_ASSERTION(aFrame != mFrame, "How did that happen?"); + + /* Now aFrame is the containing block we want */ + + /* Check whether the containing block is currently being reflowed. + If so, use the info from the reflow input. */ + const ReflowInput* reflowInput; + if (aFrame->HasAnyStateBits(NS_FRAME_IN_REFLOW)) { + for (reflowInput = mParentReflowInput; + reflowInput && reflowInput->mFrame != aFrame; + reflowInput = reflowInput->mParentReflowInput) { + /* do nothing */ + } + } else { + reflowInput = nullptr; + } + + if (reflowInput) { + WritingMode wm = reflowInput->GetWritingMode(); + NS_ASSERTION(wm == aFrame->GetWritingMode(), "unexpected writing mode"); + aCBIStartEdge = reflowInput->ComputedLogicalBorderPadding(wm).IStart(wm); + aCBSize = reflowInput->ComputedSize(wm); + } else { + /* Didn't find a reflow reflowInput for aFrame. Just compute the + information we want, on the assumption that aFrame already knows its + size. This really ought to be true by now. */ + NS_ASSERTION(!aFrame->HasAnyStateBits(NS_FRAME_IN_REFLOW), + "aFrame shouldn't be in reflow; we'll lie if it is"); + WritingMode wm = aFrame->GetWritingMode(); + // Compute CB's offset & content-box size by subtracting borderpadding from + // frame size. + const auto& bp = aFrame->GetLogicalUsedBorderAndPadding(wm); + aCBIStartEdge = bp.IStart(wm); + aCBSize = aFrame->GetLogicalSize(wm) - bp.Size(wm); + } + + return aFrame; +} + +struct nsHypotheticalPosition { + // offset from inline-start edge of containing block (which is a padding edge) + nscoord mIStart; + // offset from block-start edge of containing block (which is a padding edge) + nscoord mBStart; + WritingMode mWritingMode; +}; + +/** + * aInsideBoxSizing returns the part of the padding, border, and margin + * in the aAxis dimension that goes inside the edge given by box-sizing; + * aOutsideBoxSizing returns the rest. + */ +void ReflowInput::CalculateBorderPaddingMargin( + LogicalAxis aAxis, nscoord aContainingBlockSize, nscoord* aInsideBoxSizing, + nscoord* aOutsideBoxSizing) const { + WritingMode wm = GetWritingMode(); + mozilla::Side startSide = + wm.PhysicalSide(MakeLogicalSide(aAxis, eLogicalEdgeStart)); + mozilla::Side endSide = + wm.PhysicalSide(MakeLogicalSide(aAxis, eLogicalEdgeEnd)); + + nsMargin styleBorder = mStyleBorder->GetComputedBorder(); + nscoord borderStartEnd = + styleBorder.Side(startSide) + styleBorder.Side(endSide); + + nscoord paddingStartEnd, marginStartEnd; + + // See if the style system can provide us the padding directly + const auto* stylePadding = mFrame->StylePadding(); + if (nsMargin padding; stylePadding->GetPadding(padding)) { + paddingStartEnd = padding.Side(startSide) + padding.Side(endSide); + } else { + // We have to compute the start and end values + nscoord start, end; + start = nsLayoutUtils::ComputeCBDependentValue( + aContainingBlockSize, stylePadding->mPadding.Get(startSide)); + end = nsLayoutUtils::ComputeCBDependentValue( + aContainingBlockSize, stylePadding->mPadding.Get(endSide)); + paddingStartEnd = start + end; + } + + // See if the style system can provide us the margin directly + if (nsMargin margin; mStyleMargin->GetMargin(margin)) { + marginStartEnd = margin.Side(startSide) + margin.Side(endSide); + } else { + nscoord start, end; + // We have to compute the start and end values + if (mStyleMargin->mMargin.Get(startSide).IsAuto()) { + // We set this to 0 for now, and fix it up later in + // InitAbsoluteConstraints (which is caller of this function, via + // CalculateHypotheticalPosition). + start = 0; + } else { + start = nsLayoutUtils::ComputeCBDependentValue( + aContainingBlockSize, mStyleMargin->mMargin.Get(startSide)); + } + if (mStyleMargin->mMargin.Get(endSide).IsAuto()) { + // We set this to 0 for now, and fix it up later in + // InitAbsoluteConstraints (which is caller of this function, via + // CalculateHypotheticalPosition). + end = 0; + } else { + end = nsLayoutUtils::ComputeCBDependentValue( + aContainingBlockSize, mStyleMargin->mMargin.Get(endSide)); + } + marginStartEnd = start + end; + } + + nscoord outside = paddingStartEnd + borderStartEnd + marginStartEnd; + nscoord inside = 0; + if (mStylePosition->mBoxSizing == StyleBoxSizing::Border) { + inside = borderStartEnd + paddingStartEnd; + } + outside -= inside; + *aInsideBoxSizing = inside; + *aOutsideBoxSizing = outside; +} + +/** + * Returns true iff a pre-order traversal of the normal child + * frames rooted at aFrame finds no non-empty frame before aDescendant. + */ +static bool AreAllEarlierInFlowFramesEmpty(nsIFrame* aFrame, + nsIFrame* aDescendant, + bool* aFound) { + if (aFrame == aDescendant) { + *aFound = true; + return true; + } + if (aFrame->IsPlaceholderFrame()) { + auto ph = static_cast<nsPlaceholderFrame*>(aFrame); + MOZ_ASSERT(ph->IsSelfEmpty() && ph->PrincipalChildList().IsEmpty()); + ph->SetLineIsEmptySoFar(true); + } else { + if (!aFrame->IsSelfEmpty()) { + *aFound = false; + return false; + } + for (nsIFrame* f : aFrame->PrincipalChildList()) { + bool allEmpty = AreAllEarlierInFlowFramesEmpty(f, aDescendant, aFound); + if (*aFound || !allEmpty) { + return allEmpty; + } + } + } + *aFound = false; + return true; +} + +static bool AxisPolarityFlipped(LogicalAxis aThisAxis, WritingMode aThisWm, + WritingMode aOtherWm) { + if (MOZ_LIKELY(aThisWm == aOtherWm)) { + // Dedicated short circuit for the common case. + return false; + } + LogicalAxis otherAxis = aThisWm.IsOrthogonalTo(aOtherWm) + ? GetOrthogonalAxis(aThisAxis) + : aThisAxis; + NS_ASSERTION( + aThisWm.PhysicalAxis(aThisAxis) == aOtherWm.PhysicalAxis(otherAxis), + "Physical axes must match!"); + Side thisStartSide = + aThisWm.PhysicalSide(MakeLogicalSide(aThisAxis, eLogicalEdgeStart)); + Side otherStartSide = + aOtherWm.PhysicalSide(MakeLogicalSide(otherAxis, eLogicalEdgeStart)); + return thisStartSide != otherStartSide; +} + +static bool InlinePolarityFlipped(WritingMode aThisWm, WritingMode aOtherWm) { + return AxisPolarityFlipped(eLogicalAxisInline, aThisWm, aOtherWm); +} + +static bool BlockPolarityFlipped(WritingMode aThisWm, WritingMode aOtherWm) { + return AxisPolarityFlipped(eLogicalAxisBlock, aThisWm, aOtherWm); +} + +// Calculate the position of the hypothetical box that the element would have +// if it were in the flow. +// The values returned are relative to the padding edge of the absolute +// containing block. The writing-mode of the hypothetical box position will +// have the same block direction as the absolute containing block, but may +// differ in inline-bidi direction. +// In the code below, |aCBReflowInput->frame| is the absolute containing block, +// while |containingBlock| is the nearest block container of the placeholder +// frame, which may be different from the absolute containing block. +void ReflowInput::CalculateHypotheticalPosition( + nsPresContext* aPresContext, nsPlaceholderFrame* aPlaceholderFrame, + const ReflowInput* aCBReflowInput, nsHypotheticalPosition& aHypotheticalPos, + LayoutFrameType aFrameType) const { + NS_ASSERTION(mStyleDisplay->mOriginalDisplay != StyleDisplay::None, + "mOriginalDisplay has not been properly initialized"); + + // Find the nearest containing block frame to the placeholder frame, + // and its inline-start edge and width. + nscoord blockIStartContentEdge; + // Dummy writing mode for blockContentSize, will be changed as needed by + // GetHypotheticalBoxContainer. + WritingMode cbwm = aCBReflowInput->GetWritingMode(); + LogicalSize blockContentSize(cbwm); + nsIFrame* containingBlock = GetHypotheticalBoxContainer( + aPlaceholderFrame, blockIStartContentEdge, blockContentSize); + // Now blockContentSize is in containingBlock's writing mode. + + // If it's a replaced element and it has a 'auto' value for + //'inline size', see if we can get the intrinsic size. This will allow + // us to exactly determine both the inline edges + WritingMode wm = containingBlock->GetWritingMode(); + + const auto& styleISize = mStylePosition->ISize(wm); + bool isAutoISize = styleISize.IsAuto(); + Maybe<nsSize> intrinsicSize; + if (mFlags.mIsReplaced && isAutoISize) { + // See if we can get the intrinsic size of the element + intrinsicSize = mFrame->GetIntrinsicSize().ToSize(); + } + + // See if we can calculate what the box inline size would have been if + // the element had been in the flow + Maybe<nscoord> boxISize; + if (mStyleDisplay->IsOriginalDisplayInlineOutside() && !mFlags.mIsReplaced) { + // For non-replaced inline-level elements the 'inline size' property + // doesn't apply, so we don't know what the inline size would have + // been without reflowing it + + } else { + // It's either a replaced inline-level element or a block-level element + + // Determine the total amount of inline direction + // border/padding/margin that the element would have had if it had + // been in the flow. Note that we ignore any 'auto' and 'inherit' + // values + nscoord insideBoxISizing, outsideBoxISizing; + CalculateBorderPaddingMargin(eLogicalAxisInline, blockContentSize.ISize(wm), + &insideBoxISizing, &outsideBoxISizing); + + if (mFlags.mIsReplaced && isAutoISize) { + // It's a replaced element with an 'auto' inline size so the box + // inline size is its intrinsic size plus any border/padding/margin + if (intrinsicSize) { + boxISize.emplace(LogicalSize(wm, *intrinsicSize).ISize(wm) + + outsideBoxISizing + insideBoxISizing); + } + + } else if (isAutoISize) { + // The box inline size is the containing block inline size + boxISize.emplace(blockContentSize.ISize(wm)); + } else { + // We need to compute it. It's important we do this, because if it's + // percentage based this computed value may be different from the computed + // value calculated using the absolute containing block width + nscoord insideBoxBSizing, dummy; + CalculateBorderPaddingMargin(eLogicalAxisBlock, + blockContentSize.ISize(wm), + &insideBoxBSizing, &dummy); + boxISize.emplace( + ComputeISizeValue(wm, blockContentSize, + LogicalSize(wm, insideBoxISizing, insideBoxBSizing), + outsideBoxISizing, styleISize) + + insideBoxISizing + outsideBoxISizing); + } + } + + // Get the placeholder x-offset and y-offset in the coordinate + // space of its containing block + // XXXbz the placeholder is not fully reflowed yet if our containing block is + // relatively positioned... + nsSize containerSize = + containingBlock->HasAnyStateBits(NS_FRAME_IN_REFLOW) + ? aCBReflowInput->ComputedSizeAsContainerIfConstrained() + : containingBlock->GetSize(); + LogicalPoint placeholderOffset( + wm, aPlaceholderFrame->GetOffsetToIgnoringScrolling(containingBlock), + containerSize); + + // First, determine the hypothetical box's mBStart. We want to check the + // content insertion frame of containingBlock for block-ness, but make + // sure to compute all coordinates in the coordinate system of + // containingBlock. + nsBlockFrame* blockFrame = + do_QueryFrame(containingBlock->GetContentInsertionFrame()); + if (blockFrame) { + // Use a null containerSize to convert a LogicalPoint functioning as a + // vector into a physical nsPoint vector. + const nsSize nullContainerSize; + LogicalPoint blockOffset( + wm, blockFrame->GetOffsetToIgnoringScrolling(containingBlock), + nullContainerSize); + bool isValid; + nsBlockInFlowLineIterator iter(blockFrame, aPlaceholderFrame, &isValid); + if (!isValid) { + // Give up. We're probably dealing with somebody using + // position:absolute inside native-anonymous content anyway. + aHypotheticalPos.mBStart = placeholderOffset.B(wm); + } else { + NS_ASSERTION(iter.GetContainer() == blockFrame, + "Found placeholder in wrong block!"); + nsBlockFrame::LineIterator lineBox = iter.GetLine(); + + // How we determine the hypothetical box depends on whether the element + // would have been inline-level or block-level + LogicalRect lineBounds = lineBox->GetBounds().ConvertTo( + wm, lineBox->mWritingMode, lineBox->mContainerSize); + if (mStyleDisplay->IsOriginalDisplayInlineOutside()) { + // Use the block-start of the inline box which the placeholder lives in + // as the hypothetical box's block-start. + aHypotheticalPos.mBStart = lineBounds.BStart(wm) + blockOffset.B(wm); + } else { + // The element would have been block-level which means it would + // be below the line containing the placeholder frame, unless + // all the frames before it are empty. In that case, it would + // have been just before this line. + // XXXbz the line box is not fully reflowed yet if our + // containing block is relatively positioned... + if (lineBox != iter.End()) { + nsIFrame* firstFrame = lineBox->mFirstChild; + bool allEmpty = false; + if (firstFrame == aPlaceholderFrame) { + aPlaceholderFrame->SetLineIsEmptySoFar(true); + allEmpty = true; + } else { + auto prev = aPlaceholderFrame->GetPrevSibling(); + if (prev && prev->IsPlaceholderFrame()) { + auto ph = static_cast<nsPlaceholderFrame*>(prev); + if (ph->GetLineIsEmptySoFar(&allEmpty)) { + aPlaceholderFrame->SetLineIsEmptySoFar(allEmpty); + } + } + } + if (!allEmpty) { + bool found = false; + while (firstFrame) { // See bug 223064 + allEmpty = AreAllEarlierInFlowFramesEmpty( + firstFrame, aPlaceholderFrame, &found); + if (found || !allEmpty) { + break; + } + firstFrame = firstFrame->GetNextSibling(); + } + aPlaceholderFrame->SetLineIsEmptySoFar(allEmpty); + } + NS_ASSERTION(firstFrame, "Couldn't find placeholder!"); + + if (allEmpty) { + // The top of the hypothetical box is the top of the line + // containing the placeholder, since there is nothing in the + // line before our placeholder except empty frames. + aHypotheticalPos.mBStart = + lineBounds.BStart(wm) + blockOffset.B(wm); + } else { + // The top of the hypothetical box is just below the line + // containing the placeholder. + aHypotheticalPos.mBStart = lineBounds.BEnd(wm) + blockOffset.B(wm); + } + } else { + // Just use the placeholder's block-offset wrt the containing block + aHypotheticalPos.mBStart = placeholderOffset.B(wm); + } + } + } + } else { + // The containing block is not a block, so it's probably something + // like a XUL box, etc. + // Just use the placeholder's block-offset + aHypotheticalPos.mBStart = placeholderOffset.B(wm); + } + + // Second, determine the hypothetical box's mIStart. + // How we determine the hypothetical box depends on whether the element + // would have been inline-level or block-level + if (mStyleDisplay->IsOriginalDisplayInlineOutside() || + mFlags.mIOffsetsNeedCSSAlign) { + // The placeholder represents the IStart edge of the hypothetical box. + // (Or if mFlags.mIOffsetsNeedCSSAlign is set, it represents the IStart + // edge of the Alignment Container.) + aHypotheticalPos.mIStart = placeholderOffset.I(wm); + } else { + aHypotheticalPos.mIStart = blockIStartContentEdge; + } + + // The current coordinate space is that of the nearest block to the + // placeholder. Convert to the coordinate space of the absolute containing + // block. + nsPoint cbOffset = + containingBlock->GetOffsetToIgnoringScrolling(aCBReflowInput->mFrame); + + nsSize reflowSize = aCBReflowInput->ComputedSizeAsContainerIfConstrained(); + LogicalPoint logCBOffs(wm, cbOffset, reflowSize - containerSize); + aHypotheticalPos.mIStart += logCBOffs.I(wm); + aHypotheticalPos.mBStart += logCBOffs.B(wm); + + // If block direction doesn't match (whether orthogonal or antiparallel), + // we'll have to convert aHypotheticalPos to be in terms of cbwm. + // This upcoming conversion must be taken into account for border offsets. + const bool hypotheticalPosWillUseCbwm = + cbwm.GetBlockDir() != wm.GetBlockDir(); + // The specified offsets are relative to the absolute containing block's + // padding edge and our current values are relative to the border edge, so + // translate. + const LogicalMargin border = aCBReflowInput->ComputedLogicalBorder(wm); + if (hypotheticalPosWillUseCbwm && InlinePolarityFlipped(wm, cbwm)) { + aHypotheticalPos.mIStart += border.IEnd(wm); + } else { + aHypotheticalPos.mIStart -= border.IStart(wm); + } + + if (hypotheticalPosWillUseCbwm && BlockPolarityFlipped(wm, cbwm)) { + aHypotheticalPos.mBStart += border.BEnd(wm); + } else { + aHypotheticalPos.mBStart -= border.BStart(wm); + } + // At this point, we have computed aHypotheticalPos using the writing mode + // of the placeholder's containing block. + + if (hypotheticalPosWillUseCbwm) { + // If the block direction we used in calculating aHypotheticalPos does not + // match the absolute containing block's, we need to convert here so that + // aHypotheticalPos is usable in relation to the absolute containing block. + // This requires computing or measuring the abspos frame's block-size, + // which is not otherwise required/used here (as aHypotheticalPos + // records only the block-start coordinate). + + // This is similar to the inline-size calculation for a replaced + // inline-level element or a block-level element (above), except that + // 'auto' sizing is handled differently in the block direction for non- + // replaced elements and replaced elements lacking an intrinsic size. + + // Determine the total amount of block direction + // border/padding/margin that the element would have had if it had + // been in the flow. Note that we ignore any 'auto' and 'inherit' + // values. + nscoord insideBoxSizing, outsideBoxSizing; + CalculateBorderPaddingMargin(eLogicalAxisBlock, blockContentSize.BSize(wm), + &insideBoxSizing, &outsideBoxSizing); + + nscoord boxBSize; + const auto& styleBSize = mStylePosition->BSize(wm); + if (styleBSize.BehavesLikeInitialValueOnBlockAxis()) { + if (mFlags.mIsReplaced && intrinsicSize) { + // It's a replaced element with an 'auto' block size so the box + // block size is its intrinsic size plus any border/padding/margin + boxBSize = LogicalSize(wm, *intrinsicSize).BSize(wm) + + outsideBoxSizing + insideBoxSizing; + } else { + // XXX Bug 1191801 + // Figure out how to get the correct boxBSize here (need to reflow the + // positioned frame?) + boxBSize = 0; + } + } else { + // We need to compute it. It's important we do this, because if it's + // percentage-based this computed value may be different from the + // computed value calculated using the absolute containing block height. + boxBSize = nsLayoutUtils::ComputeBSizeValue( + blockContentSize.BSize(wm), insideBoxSizing, + styleBSize.AsLengthPercentage()) + + insideBoxSizing + outsideBoxSizing; + } + + LogicalSize boxSize(wm, boxISize.valueOr(0), boxBSize); + + LogicalPoint origin(wm, aHypotheticalPos.mIStart, aHypotheticalPos.mBStart); + origin = + origin.ConvertTo(cbwm, wm, reflowSize - boxSize.GetPhysicalSize(wm)); + + aHypotheticalPos.mIStart = origin.I(cbwm); + aHypotheticalPos.mBStart = origin.B(cbwm); + aHypotheticalPos.mWritingMode = cbwm; + } else { + aHypotheticalPos.mWritingMode = wm; + } +} + +bool ReflowInput::IsInlineSizeComputableByBlockSizeAndAspectRatio( + nscoord aBlockSize) const { + WritingMode wm = GetWritingMode(); + MOZ_ASSERT(!mStylePosition->mOffset.GetBStart(wm).IsAuto() && + !mStylePosition->mOffset.GetBEnd(wm).IsAuto(), + "If any of the block-start and block-end are auto, aBlockSize " + "doesn't make sense"); + NS_WARNING_ASSERTION( + aBlockSize >= 0 && aBlockSize != NS_UNCONSTRAINEDSIZE, + "The caller shouldn't give us an unresolved or invalid block size"); + + if (!mStylePosition->mAspectRatio.HasFiniteRatio()) { + return false; + } + + // We don't have to compute the inline size by aspect-ratio and the resolved + // block size (from insets) for replaced elements. + if (mFrame->IsFrameOfType(nsIFrame::eReplaced)) { + return false; + } + + // If inline size is specified, we should have it by mFrame->ComputeSize() + // already. + if (mStylePosition->ISize(wm).IsLengthPercentage()) { + return false; + } + + // If both inline insets are non-auto, mFrame->ComputeSize() should get a + // possible inline size by those insets, so we don't rely on aspect-ratio. + if (!mStylePosition->mOffset.GetIStart(wm).IsAuto() && + !mStylePosition->mOffset.GetIEnd(wm).IsAuto()) { + return false; + } + + // Just an error handling. If |aBlockSize| is NS_UNCONSTRAINEDSIZE, there must + // be something wrong, and we don't want to continue the calculation for + // aspect-ratio. So we return false if this happens. + return aBlockSize != NS_UNCONSTRAINEDSIZE; +} + +// FIXME: Move this into nsIFrame::ComputeSize() if possible, so most of the +// if-checks can be simplier. +LogicalSize ReflowInput::CalculateAbsoluteSizeWithResolvedAutoBlockSize( + nscoord aAutoBSize, const LogicalSize& aTentativeComputedSize) { + LogicalSize resultSize = aTentativeComputedSize; + WritingMode wm = GetWritingMode(); + + // Two cases we don't want to early return: + // 1. If the block size behaves as initial value and we haven't resolved it in + // ComputeSize() yet, we need to apply |aAutoBSize|. + // Also, we check both computed style and |resultSize.BSize(wm)| to avoid + // applying |aAutoBSize| when the resolved block size is saturated at + // nscoord_MAX, and wrongly treated as NS_UNCONSTRAINEDSIZE because of a + // giant specified block-size. + // 2. If the block size needs to be computed via aspect-ratio and + // |aAutoBSize|, we need to apply |aAutoBSize|. In this case, + // |resultSize.BSize(wm)| may not be NS_UNCONSTRAINEDSIZE because we apply + // aspect-ratio in ComputeSize() for block axis by default, so we have to + // check its computed style. + const bool bSizeBehavesAsInitial = + mStylePosition->BSize(wm).BehavesLikeInitialValueOnBlockAxis(); + const bool bSizeIsStillUnconstrained = + bSizeBehavesAsInitial && resultSize.BSize(wm) == NS_UNCONSTRAINEDSIZE; + const bool needsComputeInlineSizeByAspectRatio = + bSizeBehavesAsInitial && + IsInlineSizeComputableByBlockSizeAndAspectRatio(aAutoBSize); + if (!bSizeIsStillUnconstrained && !needsComputeInlineSizeByAspectRatio) { + return resultSize; + } + + // For non-replaced elements with block-size auto, the block-size + // fills the remaining space, and we clamp it by min/max size constraints. + resultSize.BSize(wm) = ApplyMinMaxBSize(aAutoBSize); + + if (!needsComputeInlineSizeByAspectRatio) { + return resultSize; + } + + // Calculate transferred inline size through aspect-ratio. + // For non-replaced elements, we always take box-sizing into account. + const auto boxSizingAdjust = + mStylePosition->mBoxSizing == StyleBoxSizing::Border + ? ComputedLogicalBorderPadding(wm).Size(wm) + : LogicalSize(wm); + auto transferredISize = + mStylePosition->mAspectRatio.ToLayoutRatio().ComputeRatioDependentSize( + LogicalAxis::eLogicalAxisInline, wm, aAutoBSize, boxSizingAdjust); + resultSize.ISize(wm) = ApplyMinMaxISize(transferredISize); + + MOZ_ASSERT(mFlags.mIsBSizeSetByAspectRatio, + "This flag should have been set because nsIFrame::ComputeSize() " + "returns AspectRatioUsage::ToComputeBSize unconditionally for " + "auto block-size"); + mFlags.mIsBSizeSetByAspectRatio = false; + + return resultSize; +} + +void ReflowInput::InitAbsoluteConstraints(nsPresContext* aPresContext, + const ReflowInput* aCBReflowInput, + const LogicalSize& aCBSize, + LayoutFrameType aFrameType) { + WritingMode wm = GetWritingMode(); + WritingMode cbwm = aCBReflowInput->GetWritingMode(); + NS_WARNING_ASSERTION(aCBSize.BSize(cbwm) != NS_UNCONSTRAINEDSIZE, + "containing block bsize must be constrained"); + + NS_ASSERTION(aFrameType != LayoutFrameType::Table, + "InitAbsoluteConstraints should not be called on table frames"); + NS_ASSERTION(mFrame->HasAnyStateBits(NS_FRAME_OUT_OF_FLOW), + "Why are we here?"); + + const auto& styleOffset = mStylePosition->mOffset; + bool iStartIsAuto = styleOffset.GetIStart(cbwm).IsAuto(); + bool iEndIsAuto = styleOffset.GetIEnd(cbwm).IsAuto(); + bool bStartIsAuto = styleOffset.GetBStart(cbwm).IsAuto(); + bool bEndIsAuto = styleOffset.GetBEnd(cbwm).IsAuto(); + + // If both 'left' and 'right' are 'auto' or both 'top' and 'bottom' are + // 'auto', then compute the hypothetical box position where the element would + // have been if it had been in the flow + nsHypotheticalPosition hypotheticalPos; + if ((iStartIsAuto && iEndIsAuto) || (bStartIsAuto && bEndIsAuto)) { + nsPlaceholderFrame* placeholderFrame = mFrame->GetPlaceholderFrame(); + MOZ_ASSERT(placeholderFrame, "no placeholder frame"); + nsIFrame* placeholderParent = placeholderFrame->GetParent(); + MOZ_ASSERT(placeholderParent, "shouldn't have unparented placeholders"); + + if (placeholderFrame->HasAnyStateBits( + PLACEHOLDER_STATICPOS_NEEDS_CSSALIGN)) { + MOZ_ASSERT(placeholderParent->IsFlexOrGridContainer(), + "This flag should only be set on grid/flex children"); + // If the (as-yet unknown) static position will determine the inline + // and/or block offsets, set flags to note those offsets aren't valid + // until we can do CSS Box Alignment on the OOF frame. + mFlags.mIOffsetsNeedCSSAlign = (iStartIsAuto && iEndIsAuto); + mFlags.mBOffsetsNeedCSSAlign = (bStartIsAuto && bEndIsAuto); + } + + if (mFlags.mStaticPosIsCBOrigin) { + hypotheticalPos.mWritingMode = cbwm; + hypotheticalPos.mIStart = nscoord(0); + hypotheticalPos.mBStart = nscoord(0); + if (placeholderParent->IsGridContainerFrame() && + placeholderParent->HasAnyStateBits(NS_STATE_GRID_IS_COL_MASONRY | + NS_STATE_GRID_IS_ROW_MASONRY)) { + // Disable CSS alignment in Masonry layout since we don't have real grid + // areas in that axis. We'll use the placeholder position instead as it + // was calculated by nsGridContainerFrame::MasonryLayout. + auto cbsz = aCBSize.GetPhysicalSize(cbwm); + LogicalPoint pos = placeholderFrame->GetLogicalPosition(cbwm, cbsz); + if (placeholderParent->HasAnyStateBits(NS_STATE_GRID_IS_COL_MASONRY)) { + mFlags.mIOffsetsNeedCSSAlign = false; + hypotheticalPos.mIStart = pos.I(cbwm); + } else { + mFlags.mBOffsetsNeedCSSAlign = false; + hypotheticalPos.mBStart = pos.B(cbwm); + } + } + } else { + // XXXmats all this is broken for orthogonal writing-modes: bug 1521988. + CalculateHypotheticalPosition(aPresContext, placeholderFrame, + aCBReflowInput, hypotheticalPos, + aFrameType); + if (aCBReflowInput->mFrame->IsGridContainerFrame()) { + // 'hypotheticalPos' is relative to the padding rect of the CB *frame*. + // In grid layout the CB is the grid area rectangle, so we translate + // 'hypotheticalPos' to be relative that rectangle here. + nsRect cb = nsGridContainerFrame::GridItemCB(mFrame); + nscoord left(0); + nscoord right(0); + if (cbwm.IsBidiLTR()) { + left = cb.X(); + } else { + right = aCBReflowInput->ComputedWidth() + + aCBReflowInput->ComputedPhysicalPadding().LeftRight() - + cb.XMost(); + } + LogicalMargin offsets(cbwm, nsMargin(cb.Y(), right, nscoord(0), left)); + hypotheticalPos.mIStart -= offsets.IStart(cbwm); + hypotheticalPos.mBStart -= offsets.BStart(cbwm); + } + } + } + + // Initialize the 'left' and 'right' computed offsets + // XXX Handle new 'static-position' value... + + // Size of the containing block in its writing mode + LogicalSize cbSize = aCBSize; + LogicalMargin offsets = ComputedLogicalOffsets(cbwm); + + if (iStartIsAuto) { + offsets.IStart(cbwm) = 0; + } else { + offsets.IStart(cbwm) = nsLayoutUtils::ComputeCBDependentValue( + cbSize.ISize(cbwm), styleOffset.GetIStart(cbwm)); + } + if (iEndIsAuto) { + offsets.IEnd(cbwm) = 0; + } else { + offsets.IEnd(cbwm) = nsLayoutUtils::ComputeCBDependentValue( + cbSize.ISize(cbwm), styleOffset.GetIEnd(cbwm)); + } + + if (iStartIsAuto && iEndIsAuto) { + if (cbwm.IsBidiLTR() != hypotheticalPos.mWritingMode.IsBidiLTR()) { + offsets.IEnd(cbwm) = hypotheticalPos.mIStart; + iEndIsAuto = false; + } else { + offsets.IStart(cbwm) = hypotheticalPos.mIStart; + iStartIsAuto = false; + } + } + + if (bStartIsAuto) { + offsets.BStart(cbwm) = 0; + } else { + offsets.BStart(cbwm) = nsLayoutUtils::ComputeBSizeDependentValue( + cbSize.BSize(cbwm), styleOffset.GetBStart(cbwm)); + } + if (bEndIsAuto) { + offsets.BEnd(cbwm) = 0; + } else { + offsets.BEnd(cbwm) = nsLayoutUtils::ComputeBSizeDependentValue( + cbSize.BSize(cbwm), styleOffset.GetBEnd(cbwm)); + } + + if (bStartIsAuto && bEndIsAuto) { + // Treat 'top' like 'static-position' + offsets.BStart(cbwm) = hypotheticalPos.mBStart; + bStartIsAuto = false; + } + + SetComputedLogicalOffsets(cbwm, offsets); + + if (wm.IsOrthogonalTo(cbwm)) { + if (bStartIsAuto || bEndIsAuto) { + mComputeSizeFlags += ComputeSizeFlag::ShrinkWrap; + } + } else { + if (iStartIsAuto || iEndIsAuto) { + mComputeSizeFlags += ComputeSizeFlag::ShrinkWrap; + } + } + + nsIFrame::SizeComputationResult sizeResult = { + LogicalSize(wm), nsIFrame::AspectRatioUsage::None}; + { + AutoMaybeDisableFontInflation an(mFrame); + + sizeResult = mFrame->ComputeSize( + mRenderingContext, wm, cbSize.ConvertTo(wm, cbwm), + cbSize.ConvertTo(wm, cbwm).ISize(wm), // XXX or AvailableISize()? + ComputedLogicalMargin(wm).Size(wm) + + ComputedLogicalOffsets(wm).Size(wm), + ComputedLogicalBorderPadding(wm).Size(wm), {}, mComputeSizeFlags); + mComputedSize = sizeResult.mLogicalSize; + NS_ASSERTION(ComputedISize() >= 0, "Bogus inline-size"); + NS_ASSERTION( + ComputedBSize() == NS_UNCONSTRAINEDSIZE || ComputedBSize() >= 0, + "Bogus block-size"); + } + + LogicalSize& computedSize = sizeResult.mLogicalSize; + computedSize = computedSize.ConvertTo(cbwm, wm); + + mFlags.mIsBSizeSetByAspectRatio = sizeResult.mAspectRatioUsage == + nsIFrame::AspectRatioUsage::ToComputeBSize; + + // XXX Now that we have ComputeSize, can we condense many of the + // branches off of widthIsAuto? + + LogicalMargin margin = ComputedLogicalMargin(cbwm); + const LogicalMargin borderPadding = ComputedLogicalBorderPadding(cbwm); + + bool iSizeIsAuto = mStylePosition->ISize(cbwm).IsAuto(); + bool marginIStartIsAuto = false; + bool marginIEndIsAuto = false; + bool marginBStartIsAuto = false; + bool marginBEndIsAuto = false; + if (iStartIsAuto) { + // We know 'right' is not 'auto' anymore thanks to the hypothetical + // box code above. + // Solve for 'left'. + if (iSizeIsAuto) { + // XXXldb This, and the corresponding code in + // nsAbsoluteContainingBlock.cpp, could probably go away now that + // we always compute widths. + offsets.IStart(cbwm) = NS_AUTOOFFSET; + } else { + offsets.IStart(cbwm) = cbSize.ISize(cbwm) - offsets.IEnd(cbwm) - + computedSize.ISize(cbwm) - margin.IStartEnd(cbwm) - + borderPadding.IStartEnd(cbwm); + } + } else if (iEndIsAuto) { + // We know 'left' is not 'auto' anymore thanks to the hypothetical + // box code above. + // Solve for 'right'. + if (iSizeIsAuto) { + // XXXldb This, and the corresponding code in + // nsAbsoluteContainingBlock.cpp, could probably go away now that + // we always compute widths. + offsets.IEnd(cbwm) = NS_AUTOOFFSET; + } else { + offsets.IEnd(cbwm) = cbSize.ISize(cbwm) - offsets.IStart(cbwm) - + computedSize.ISize(cbwm) - margin.IStartEnd(cbwm) - + borderPadding.IStartEnd(cbwm); + } + } else if (!mFrame->HasIntrinsicKeywordForBSize() || + !wm.IsOrthogonalTo(cbwm)) { + // Neither 'inline-start' nor 'inline-end' is 'auto'. + if (wm.IsOrthogonalTo(cbwm)) { + // For orthogonal blocks, we need to handle the case where the block had + // unconstrained block-size, which mapped to unconstrained inline-size + // in the containing block's writing mode. + nscoord autoISize = cbSize.ISize(cbwm) - margin.IStartEnd(cbwm) - + borderPadding.IStartEnd(cbwm) - + offsets.IStartEnd(cbwm); + autoISize = std::max(autoISize, 0); + // FIXME: Bug 1602669: if |autoISize| happens to be numerically equal to + // NS_UNCONSTRAINEDSIZE, we may get some unexpected behavior. We need a + // better way to distinguish between unconstrained size and resolved + // size. + NS_WARNING_ASSERTION(autoISize != NS_UNCONSTRAINEDSIZE, + "Unexpected size from inline-start and inline-end"); + + nscoord autoBSizeInWM = autoISize; + LogicalSize computedSizeInWM = + CalculateAbsoluteSizeWithResolvedAutoBlockSize( + autoBSizeInWM, computedSize.ConvertTo(wm, cbwm)); + computedSize = computedSizeInWM.ConvertTo(cbwm, wm); + } + + // However, the inline-size might + // still not fill all the available space (even though we didn't + // shrink-wrap) in case: + // * inline-size was specified + // * we're dealing with a replaced element + // * width was constrained by min- or max-inline-size. + + nscoord availMarginSpace = + aCBSize.ISize(cbwm) - offsets.IStartEnd(cbwm) - margin.IStartEnd(cbwm) - + borderPadding.IStartEnd(cbwm) - computedSize.ISize(cbwm); + marginIStartIsAuto = mStyleMargin->mMargin.GetIStart(cbwm).IsAuto(); + marginIEndIsAuto = mStyleMargin->mMargin.GetIEnd(cbwm).IsAuto(); + ComputeAbsPosInlineAutoMargin(availMarginSpace, cbwm, marginIStartIsAuto, + marginIEndIsAuto, margin, offsets); + } + + bool bSizeIsAuto = + mStylePosition->BSize(cbwm).BehavesLikeInitialValueOnBlockAxis(); + if (bStartIsAuto) { + // solve for block-start + if (bSizeIsAuto) { + offsets.BStart(cbwm) = NS_AUTOOFFSET; + } else { + offsets.BStart(cbwm) = cbSize.BSize(cbwm) - margin.BStartEnd(cbwm) - + borderPadding.BStartEnd(cbwm) - + computedSize.BSize(cbwm) - offsets.BEnd(cbwm); + } + } else if (bEndIsAuto) { + // solve for block-end + if (bSizeIsAuto) { + offsets.BEnd(cbwm) = NS_AUTOOFFSET; + } else { + offsets.BEnd(cbwm) = cbSize.BSize(cbwm) - margin.BStartEnd(cbwm) - + borderPadding.BStartEnd(cbwm) - + computedSize.BSize(cbwm) - offsets.BStart(cbwm); + } + } else if (!mFrame->HasIntrinsicKeywordForBSize() || + wm.IsOrthogonalTo(cbwm)) { + // Neither block-start nor -end is 'auto'. + nscoord autoBSize = cbSize.BSize(cbwm) - margin.BStartEnd(cbwm) - + borderPadding.BStartEnd(cbwm) - offsets.BStartEnd(cbwm); + autoBSize = std::max(autoBSize, 0); + // FIXME: Bug 1602669: if |autoBSize| happens to be numerically equal to + // NS_UNCONSTRAINEDSIZE, we may get some unexpected behavior. We need a + // better way to distinguish between unconstrained size and resolved size. + NS_WARNING_ASSERTION(autoBSize != NS_UNCONSTRAINEDSIZE, + "Unexpected size from block-start and block-end"); + + // For orthogonal case, the inline size in |wm| should have been handled by + // ComputeSize(). In other words, we only have to apply |autoBSize| to + // the computed size if this value can represent the block size in |wm|. + if (!wm.IsOrthogonalTo(cbwm)) { + // We handle the unconstrained block-size in current block's writing + // mode 'wm'. + LogicalSize computedSizeInWM = + CalculateAbsoluteSizeWithResolvedAutoBlockSize( + autoBSize, computedSize.ConvertTo(wm, cbwm)); + computedSize = computedSizeInWM.ConvertTo(cbwm, wm); + } + + // The block-size might still not fill all the available space in case: + // * bsize was specified + // * we're dealing with a replaced element + // * bsize was constrained by min- or max-bsize. + nscoord availMarginSpace = autoBSize - computedSize.BSize(cbwm); + marginBStartIsAuto = mStyleMargin->mMargin.GetBStart(cbwm).IsAuto(); + marginBEndIsAuto = mStyleMargin->mMargin.GetBEnd(cbwm).IsAuto(); + + ComputeAbsPosBlockAutoMargin(availMarginSpace, cbwm, marginBStartIsAuto, + marginBEndIsAuto, margin, offsets); + } + mComputedSize = computedSize.ConvertTo(wm, cbwm); + + SetComputedLogicalOffsets(cbwm, offsets); + SetComputedLogicalMargin(cbwm, margin); + + // If we have auto margins, update our UsedMarginProperty. The property + // will have already been created by InitOffsets if it is needed. + if (marginIStartIsAuto || marginIEndIsAuto || marginBStartIsAuto || + marginBEndIsAuto) { + nsMargin* propValue = mFrame->GetProperty(nsIFrame::UsedMarginProperty()); + MOZ_ASSERT(propValue, + "UsedMarginProperty should have been created " + "by InitOffsets."); + *propValue = margin.GetPhysicalMargin(cbwm); + } +} + +// This will not be converted to abstract coordinates because it's only +// used in CalcQuirkContainingBlockHeight +static nscoord GetBlockMarginBorderPadding(const ReflowInput* aReflowInput) { + nscoord result = 0; + if (!aReflowInput) return result; + + // zero auto margins + nsMargin margin = aReflowInput->ComputedPhysicalMargin(); + if (NS_AUTOMARGIN == margin.top) margin.top = 0; + if (NS_AUTOMARGIN == margin.bottom) margin.bottom = 0; + + result += margin.top + margin.bottom; + result += aReflowInput->ComputedPhysicalBorderPadding().top + + aReflowInput->ComputedPhysicalBorderPadding().bottom; + + return result; +} + +/* Get the height based on the viewport of the containing block specified + * in aReflowInput when the containing block has mComputedHeight == + * NS_UNCONSTRAINEDSIZE This will walk up the chain of containing blocks looking + * for a computed height until it finds the canvas frame, or it encounters a + * frame that is not a block, area, or scroll frame. This handles compatibility + * with IE (see bug 85016 and bug 219693) + * + * When we encounter scrolledContent block frames, we skip over them, + * since they are guaranteed to not be useful for computing the containing + * block. + * + * See also IsQuirkContainingBlockHeight. + */ +static nscoord CalcQuirkContainingBlockHeight( + const ReflowInput* aCBReflowInput) { + const ReflowInput* firstAncestorRI = nullptr; // a candidate for html frame + const ReflowInput* secondAncestorRI = nullptr; // a candidate for body frame + + // initialize the default to NS_UNCONSTRAINEDSIZE as this is the containings + // block computed height when this function is called. It is possible that we + // don't alter this height especially if we are restricted to one level + nscoord result = NS_UNCONSTRAINEDSIZE; + + const ReflowInput* ri = aCBReflowInput; + for (; ri; ri = ri->mParentReflowInput) { + LayoutFrameType frameType = ri->mFrame->Type(); + // if the ancestor is auto height then skip it and continue up if it + // is the first block frame and possibly the body/html + if (LayoutFrameType::Block == frameType || + LayoutFrameType::Scroll == frameType) { + secondAncestorRI = firstAncestorRI; + firstAncestorRI = ri; + + // If the current frame we're looking at is positioned, we don't want to + // go any further (see bug 221784). The behavior we want here is: 1) If + // not auto-height, use this as the percentage base. 2) If auto-height, + // keep looking, unless the frame is positioned. + if (NS_UNCONSTRAINEDSIZE == ri->ComputedHeight()) { + if (ri->mFrame->IsAbsolutelyPositioned(ri->mStyleDisplay)) { + break; + } else { + continue; + } + } + } else if (LayoutFrameType::Canvas == frameType) { + // Always continue on to the height calculation + } else if (LayoutFrameType::PageContent == frameType) { + nsIFrame* prevInFlow = ri->mFrame->GetPrevInFlow(); + // only use the page content frame for a height basis if it is the first + // in flow + if (prevInFlow) break; + } else { + break; + } + + // if the ancestor is the page content frame then the percent base is + // the avail height, otherwise it is the computed height + result = (LayoutFrameType::PageContent == frameType) ? ri->AvailableHeight() + : ri->ComputedHeight(); + // if unconstrained - don't sutract borders - would result in huge height + if (NS_UNCONSTRAINEDSIZE == result) return result; + + // if we got to the canvas or page content frame, then subtract out + // margin/border/padding for the BODY and HTML elements + if ((LayoutFrameType::Canvas == frameType) || + (LayoutFrameType::PageContent == frameType)) { + result -= GetBlockMarginBorderPadding(firstAncestorRI); + result -= GetBlockMarginBorderPadding(secondAncestorRI); + +#ifdef DEBUG + // make sure the first ancestor is the HTML and the second is the BODY + if (firstAncestorRI) { + nsIContent* frameContent = firstAncestorRI->mFrame->GetContent(); + if (frameContent) { + NS_ASSERTION(frameContent->IsHTMLElement(nsGkAtoms::html), + "First ancestor is not HTML"); + } + } + if (secondAncestorRI) { + nsIContent* frameContent = secondAncestorRI->mFrame->GetContent(); + if (frameContent) { + NS_ASSERTION(frameContent->IsHTMLElement(nsGkAtoms::body), + "Second ancestor is not BODY"); + } + } +#endif + + } + // if we got to the html frame (a block child of the canvas) ... + else if (LayoutFrameType::Block == frameType && ri->mParentReflowInput && + ri->mParentReflowInput->mFrame->IsCanvasFrame()) { + // ... then subtract out margin/border/padding for the BODY element + result -= GetBlockMarginBorderPadding(secondAncestorRI); + } + break; + } + + // Make sure not to return a negative height here! + return std::max(result, 0); +} + +// Called by InitConstraints() to compute the containing block rectangle for +// the element. Handles the special logic for absolutely positioned elements +LogicalSize ReflowInput::ComputeContainingBlockRectangle( + nsPresContext* aPresContext, const ReflowInput* aContainingBlockRI) const { + // Unless the element is absolutely positioned, the containing block is + // formed by the content edge of the nearest block-level ancestor + LogicalSize cbSize = aContainingBlockRI->ComputedSize(); + + WritingMode wm = aContainingBlockRI->GetWritingMode(); + + if (aContainingBlockRI->mFlags.mTreatBSizeAsIndefinite) { + cbSize.BSize(wm) = NS_UNCONSTRAINEDSIZE; + } + + if (((mFrame->HasAnyStateBits(NS_FRAME_OUT_OF_FLOW) && + // XXXfr hack for making frames behave properly when in overflow + // container lists, see bug 154892; need to revisit later + !mFrame->GetPrevInFlow()) || + (mFrame->IsTableFrame() && + mFrame->GetParent()->HasAnyStateBits(NS_FRAME_OUT_OF_FLOW))) && + mStyleDisplay->IsAbsolutelyPositioned(mFrame)) { + // See if the ancestor is block-level or inline-level + const auto computedPadding = aContainingBlockRI->ComputedLogicalPadding(wm); + if (aContainingBlockRI->mStyleDisplay->IsInlineOutsideStyle()) { + // Base our size on the actual size of the frame. In cases when this is + // completely bogus (eg initial reflow), this code shouldn't even be + // called, since the code in nsInlineFrame::Reflow will pass in + // the containing block dimensions to our constructor. + // XXXbz we should be taking the in-flows into account too, but + // that's very hard. + + LogicalMargin computedBorder = + aContainingBlockRI->ComputedLogicalBorderPadding(wm) - + computedPadding; + cbSize.ISize(wm) = + aContainingBlockRI->mFrame->ISize(wm) - computedBorder.IStartEnd(wm); + NS_ASSERTION(cbSize.ISize(wm) >= 0, "Negative containing block isize!"); + cbSize.BSize(wm) = + aContainingBlockRI->mFrame->BSize(wm) - computedBorder.BStartEnd(wm); + NS_ASSERTION(cbSize.BSize(wm) >= 0, "Negative containing block bsize!"); + } else { + // If the ancestor is block-level, the containing block is formed by the + // padding edge of the ancestor + cbSize += computedPadding.Size(wm); + } + } else { + auto IsQuirky = [](const StyleSize& aSize) -> bool { + return aSize.ConvertsToPercentage(); + }; + // an element in quirks mode gets a containing block based on looking for a + // parent with a non-auto height if the element has a percent height. + // Note: We don't emulate this quirk for percents in calc(), or in vertical + // writing modes, or if the containing block is a flex or grid item. + if (!wm.IsVertical() && NS_UNCONSTRAINEDSIZE == cbSize.BSize(wm)) { + if (eCompatibility_NavQuirks == aPresContext->CompatibilityMode() && + !aContainingBlockRI->mFrame->IsFlexOrGridItem() && + (IsQuirky(mStylePosition->mHeight) || + (mFrame->IsTableWrapperFrame() && + IsQuirky(mFrame->PrincipalChildList() + .FirstChild() + ->StylePosition() + ->mHeight)))) { + cbSize.BSize(wm) = CalcQuirkContainingBlockHeight(aContainingBlockRI); + } + } + } + + return cbSize.ConvertTo(GetWritingMode(), wm); +} + +// XXX refactor this code to have methods for each set of properties +// we are computing: width,height,line-height; margin; offsets + +void ReflowInput::InitConstraints( + nsPresContext* aPresContext, const Maybe<LogicalSize>& aContainingBlockSize, + const Maybe<LogicalMargin>& aBorder, const Maybe<LogicalMargin>& aPadding, + LayoutFrameType aFrameType) { + WritingMode wm = GetWritingMode(); + LogicalSize cbSize = aContainingBlockSize.valueOr( + LogicalSize(mWritingMode, NS_UNCONSTRAINEDSIZE, NS_UNCONSTRAINEDSIZE)); + DISPLAY_INIT_CONSTRAINTS(mFrame, this, cbSize.ISize(wm), cbSize.BSize(wm), + aBorder, aPadding); + + // If this is a reflow root, then set the computed width and + // height equal to the available space + if (nullptr == mParentReflowInput || mFlags.mDummyParentReflowInput) { + // XXXldb This doesn't mean what it used to! + InitOffsets(wm, cbSize.ISize(wm), aFrameType, mComputeSizeFlags, aBorder, + aPadding, mStyleDisplay); + // Override mComputedMargin since reflow roots start from the + // frame's boundary, which is inside the margin. + SetComputedLogicalMargin(wm, LogicalMargin(wm)); + SetComputedLogicalOffsets(wm, LogicalMargin(wm)); + + const auto borderPadding = ComputedLogicalBorderPadding(wm); + SetComputedISize( + std::max(0, AvailableISize() - borderPadding.IStartEnd(wm)), + ResetResizeFlags::No); + SetComputedBSize( + AvailableBSize() != NS_UNCONSTRAINEDSIZE + ? std::max(0, AvailableBSize() - borderPadding.BStartEnd(wm)) + : NS_UNCONSTRAINEDSIZE, + ResetResizeFlags::No); + + mComputedMinSize.SizeTo(mWritingMode, 0, 0); + mComputedMaxSize.SizeTo(mWritingMode, NS_UNCONSTRAINEDSIZE, + NS_UNCONSTRAINEDSIZE); + } else { + // Get the containing block's reflow input + const ReflowInput* cbri = mCBReflowInput; + MOZ_ASSERT(cbri, "no containing block"); + MOZ_ASSERT(mFrame->GetParent()); + + // If we weren't given a containing block size, then compute one. + if (aContainingBlockSize.isNothing()) { + cbSize = ComputeContainingBlockRectangle(aPresContext, cbri); + } + + // See if the containing block height is based on the size of its + // content + if (NS_UNCONSTRAINEDSIZE == cbSize.BSize(wm)) { + // See if the containing block is a cell frame which needs + // to use the mComputedHeight of the cell instead of what the cell block + // passed in. + // XXX It seems like this could lead to bugs with min-height and friends + if (cbri->mParentReflowInput && cbri->mFrame->IsTableCellFrame()) { + cbSize.BSize(wm) = cbri->ComputedSize(wm).BSize(wm); + } + } + + // XXX Might need to also pass the CB height (not width) for page boxes, + // too, if we implement them. + + // For calculating positioning offsets, margins, borders and + // padding, we use the writing mode of the containing block + WritingMode cbwm = cbri->GetWritingMode(); + InitOffsets(cbwm, cbSize.ConvertTo(cbwm, wm).ISize(cbwm), aFrameType, + mComputeSizeFlags, aBorder, aPadding, mStyleDisplay); + + // For calculating the size of this box, we use its own writing mode + const auto& blockSize = mStylePosition->BSize(wm); + bool isAutoBSize = blockSize.BehavesLikeInitialValueOnBlockAxis(); + + // Check for a percentage based block size and a containing block + // block size that depends on the content block size + if (blockSize.HasPercent()) { + if (NS_UNCONSTRAINEDSIZE == cbSize.BSize(wm)) { + // this if clause enables %-blockSize on replaced inline frames, + // such as images. See bug 54119. The else clause "blockSizeUnit = + // eStyleUnit_Auto;" used to be called exclusively. + if (mFlags.mIsReplaced && mStyleDisplay->IsInlineOutsideStyle()) { + // Get the containing block's reflow input + NS_ASSERTION(nullptr != cbri, "no containing block"); + // in quirks mode, get the cb height using the special quirk method + if (!wm.IsVertical() && + eCompatibility_NavQuirks == aPresContext->CompatibilityMode()) { + if (!cbri->mFrame->IsTableCellFrame() && + !cbri->mFrame->IsFlexOrGridItem()) { + cbSize.BSize(wm) = CalcQuirkContainingBlockHeight(cbri); + if (cbSize.BSize(wm) == NS_UNCONSTRAINEDSIZE) { + isAutoBSize = true; + } + } else { + isAutoBSize = true; + } + } + // in standard mode, use the cb block size. if it's "auto", + // as will be the case by default in BODY, use auto block size + // as per CSS2 spec. + else { + nscoord computedBSize = cbri->ComputedSize(wm).BSize(wm); + if (NS_UNCONSTRAINEDSIZE != computedBSize) { + cbSize.BSize(wm) = computedBSize; + } else { + isAutoBSize = true; + } + } + } else { + // default to interpreting the blockSize like 'auto' + isAutoBSize = true; + } + } + } + + // Compute our offsets if the element is relatively positioned. We + // need the correct containing block inline-size and block-size + // here, which is why we need to do it after all the quirks-n-such + // above. (If the element is sticky positioned, we need to wait + // until the scroll container knows its size, so we compute offsets + // from StickyScrollContainer::UpdatePositions.) + if (mStyleDisplay->IsRelativelyPositioned(mFrame)) { + const LogicalMargin offsets = + ComputeRelativeOffsets(cbwm, mFrame, cbSize.ConvertTo(cbwm, wm)); + SetComputedLogicalOffsets(cbwm, offsets); + } else { + // Initialize offsets to 0 + SetComputedLogicalOffsets(wm, LogicalMargin(wm)); + } + + // Calculate the computed values for min and max properties. Note that + // this MUST come after we've computed our border and padding. + ComputeMinMaxValues(cbSize); + + // Calculate the computed inlineSize and blockSize. + // This varies by frame type. + + if (IsInternalTableFrame()) { + // Internal table elements. The rules vary depending on the type. + // Calculate the computed isize + bool rowOrRowGroup = false; + const auto& inlineSize = mStylePosition->ISize(wm); + bool isAutoISize = inlineSize.IsAuto(); + if ((StyleDisplay::TableRow == mStyleDisplay->mDisplay) || + (StyleDisplay::TableRowGroup == mStyleDisplay->mDisplay)) { + // 'inlineSize' property doesn't apply to table rows and row groups + isAutoISize = true; + rowOrRowGroup = true; + } + + // calc() with both percentages and lengths act like auto on internal + // table elements + if (isAutoISize || inlineSize.HasLengthAndPercentage()) { + if (AvailableISize() != NS_UNCONSTRAINEDSIZE && !rowOrRowGroup) { + // Internal table elements don't have margins. Only tables and + // cells have border and padding + SetComputedISize( + std::max(0, AvailableISize() - + ComputedLogicalBorderPadding(wm).IStartEnd(wm)), + ResetResizeFlags::No); + } else { + SetComputedISize(AvailableISize(), ResetResizeFlags::No); + } + NS_ASSERTION(ComputedISize() >= 0, "Bogus computed isize"); + + } else { + SetComputedISize( + ComputeISizeValue(cbSize, mStylePosition->mBoxSizing, inlineSize), + ResetResizeFlags::No); + } + + // Calculate the computed block size + if (StyleDisplay::TableColumn == mStyleDisplay->mDisplay || + StyleDisplay::TableColumnGroup == mStyleDisplay->mDisplay) { + // 'blockSize' property doesn't apply to table columns and column groups + isAutoBSize = true; + } + // calc() with both percentages and lengths acts like 'auto' on internal + // table elements + if (isAutoBSize || blockSize.HasLengthAndPercentage()) { + SetComputedBSize(NS_UNCONSTRAINEDSIZE, ResetResizeFlags::No); + } else { + SetComputedBSize( + ComputeBSizeValue(cbSize.BSize(wm), mStylePosition->mBoxSizing, + blockSize.AsLengthPercentage()), + ResetResizeFlags::No); + } + + // Doesn't apply to internal table elements + mComputedMinSize.SizeTo(mWritingMode, 0, 0); + mComputedMaxSize.SizeTo(mWritingMode, NS_UNCONSTRAINEDSIZE, + NS_UNCONSTRAINEDSIZE); + } else if (mFrame->HasAnyStateBits(NS_FRAME_OUT_OF_FLOW) && + mStyleDisplay->IsAbsolutelyPositionedStyle() && + // XXXfr hack for making frames behave properly when in overflow + // container lists, see bug 154892; need to revisit later + !mFrame->GetPrevInFlow()) { + InitAbsoluteConstraints(aPresContext, cbri, + cbSize.ConvertTo(cbri->GetWritingMode(), wm), + aFrameType); + } else { + AutoMaybeDisableFontInflation an(mFrame); + + const bool isBlockLevel = + ((!mStyleDisplay->IsInlineOutsideStyle() && + // internal table values on replaced elements behaves as inline + // https://drafts.csswg.org/css-tables-3/#table-structure + // "... it is handled instead as though the author had declared + // either 'block' (for 'table' display) or 'inline' (for all + // other values)" + !(mFlags.mIsReplaced && (mStyleDisplay->IsInnerTableStyle() || + mStyleDisplay->DisplayOutside() == + StyleDisplayOutside::TableCaption))) || + // The inner table frame always fills its outer wrapper table frame, + // even for 'inline-table'. + mFrame->IsTableFrame()) && + // XXX abs.pos. continuations treated like blocks, see comment in + // the else-if condition above. + (!mFrame->HasAnyStateBits(NS_FRAME_OUT_OF_FLOW) || + mStyleDisplay->IsAbsolutelyPositionedStyle()); + + if (!isBlockLevel) { + mComputeSizeFlags += ComputeSizeFlag::ShrinkWrap; + } + + nsIFrame* alignCB = mFrame->GetParent(); + if (alignCB->IsTableWrapperFrame() && alignCB->GetParent()) { + // XXX grid-specific for now; maybe remove this check after we address + // bug 799725 + if (alignCB->GetParent()->IsGridContainerFrame()) { + alignCB = alignCB->GetParent(); + } + } + if (alignCB->IsGridContainerFrame()) { + // Shrink-wrap grid items that will be aligned (rather than stretched) + // in its inline axis. + auto inlineAxisAlignment = + wm.IsOrthogonalTo(cbwm) + ? mStylePosition->UsedAlignSelf(alignCB->Style())._0 + : mStylePosition->UsedJustifySelf(alignCB->Style())._0; + if ((inlineAxisAlignment != StyleAlignFlags::STRETCH && + inlineAxisAlignment != StyleAlignFlags::NORMAL) || + mStyleMargin->mMargin.GetIStart(wm).IsAuto() || + mStyleMargin->mMargin.GetIEnd(wm).IsAuto()) { + mComputeSizeFlags += ComputeSizeFlag::ShrinkWrap; + } + } else { + // Shrink-wrap blocks that are orthogonal to their container. + if (isBlockLevel && mCBReflowInput && + mCBReflowInput->GetWritingMode().IsOrthogonalTo(mWritingMode)) { + mComputeSizeFlags += ComputeSizeFlag::ShrinkWrap; + } + + if (alignCB->IsFlexContainerFrame()) { + mComputeSizeFlags += ComputeSizeFlag::ShrinkWrap; + } + } + + if (cbSize.ISize(wm) == NS_UNCONSTRAINEDSIZE) { + // For orthogonal flows, where we found a parent orthogonal-limit + // for AvailableISize() in Init(), we'll use the same here as well. + cbSize.ISize(wm) = AvailableISize(); + } + + auto size = + mFrame->ComputeSize(mRenderingContext, wm, cbSize, AvailableISize(), + ComputedLogicalMargin(wm).Size(wm), + ComputedLogicalBorderPadding(wm).Size(wm), + mStyleSizeOverrides, mComputeSizeFlags); + + mComputedSize = size.mLogicalSize; + NS_ASSERTION(ComputedISize() >= 0, "Bogus inline-size"); + NS_ASSERTION( + ComputedBSize() == NS_UNCONSTRAINEDSIZE || ComputedBSize() >= 0, + "Bogus block-size"); + + mFlags.mIsBSizeSetByAspectRatio = + size.mAspectRatioUsage == nsIFrame::AspectRatioUsage::ToComputeBSize; + + const bool shouldCalculateBlockSideMargins = [&]() { + if (!isBlockLevel) { + return false; + } + if (mStyleDisplay->mDisplay == StyleDisplay::InlineTable) { + return false; + } + if (mFrame->IsTableFrame()) { + return false; + } + if (alignCB->IsFlexOrGridContainer()) { + // Exclude flex and grid items. + return false; + } + const auto pseudoType = mFrame->Style()->GetPseudoType(); + if (pseudoType == PseudoStyleType::marker && + mFrame->GetParent()->StyleList()->mListStylePosition == + StyleListStylePosition::Outside) { + // Exclude outside ::markers. + return false; + } + if (pseudoType == PseudoStyleType::columnContent) { + // Exclude -moz-column-content since it cannot have any margin. + return false; + } + return true; + }(); + + if (shouldCalculateBlockSideMargins) { + CalculateBlockSideMargins(); + } + } + } + + // Save our containing block dimensions + mContainingBlockSize = cbSize; +} + +static void UpdateProp(nsIFrame* aFrame, + const FramePropertyDescriptor<nsMargin>* aProperty, + bool aNeeded, const nsMargin& aNewValue) { + if (aNeeded) { + nsMargin* propValue = aFrame->GetProperty(aProperty); + if (propValue) { + *propValue = aNewValue; + } else { + aFrame->AddProperty(aProperty, new nsMargin(aNewValue)); + } + } else { + aFrame->RemoveProperty(aProperty); + } +} + +void SizeComputationInput::InitOffsets(WritingMode aCBWM, nscoord aPercentBasis, + LayoutFrameType aFrameType, + ComputeSizeFlags aFlags, + const Maybe<LogicalMargin>& aBorder, + const Maybe<LogicalMargin>& aPadding, + const nsStyleDisplay* aDisplay) { + DISPLAY_INIT_OFFSETS(mFrame, this, aPercentBasis, aCBWM, aBorder, aPadding); + + // Since we are in reflow, we don't need to store these properties anymore + // unless they are dependent on width, in which case we store the new value. + nsPresContext* presContext = mFrame->PresContext(); + mFrame->RemoveProperty(nsIFrame::UsedBorderProperty()); + + // Compute margins from the specified margin style information. These + // become the default computed values, and may be adjusted below + // XXX fix to provide 0,0 for the top&bottom margins for + // inline-non-replaced elements + bool needMarginProp = ComputeMargin(aCBWM, aPercentBasis, aFrameType); + // Note that ComputeMargin() simplistically resolves 'auto' margins to 0. + // In formatting contexts where this isn't correct, some later code will + // need to update the UsedMargin() property with the actual resolved value. + // One example of this is ::CalculateBlockSideMargins(). + ::UpdateProp(mFrame, nsIFrame::UsedMarginProperty(), needMarginProp, + ComputedPhysicalMargin()); + + const WritingMode wm = GetWritingMode(); + const nsStyleDisplay* disp = mFrame->StyleDisplayWithOptionalParam(aDisplay); + bool needPaddingProp; + LayoutDeviceIntMargin widgetPadding; + if (mIsThemed && presContext->Theme()->GetWidgetPadding( + presContext->DeviceContext(), mFrame, + disp->EffectiveAppearance(), &widgetPadding)) { + const nsMargin padding = LayoutDevicePixel::ToAppUnits( + widgetPadding, presContext->AppUnitsPerDevPixel()); + SetComputedLogicalPadding(wm, LogicalMargin(wm, padding)); + needPaddingProp = false; + } else if (mFrame->IsInSVGTextSubtree()) { + SetComputedLogicalPadding(wm, LogicalMargin(wm)); + needPaddingProp = false; + } else if (aPadding) { // padding is an input arg + SetComputedLogicalPadding(wm, *aPadding); + nsMargin stylePadding; + // If the caller passes a padding that doesn't match our style (like + // nsTextControlFrame might due due to theming), then we also need a + // padding prop. + needPaddingProp = !mFrame->StylePadding()->GetPadding(stylePadding) || + aPadding->GetPhysicalMargin(wm) != stylePadding; + } else { + needPaddingProp = ComputePadding(aCBWM, aPercentBasis, aFrameType); + } + + // Add [align|justify]-content:baseline padding contribution. + typedef const FramePropertyDescriptor<SmallValueHolder<nscoord>>* Prop; + auto ApplyBaselinePadding = [this, wm, &needPaddingProp](LogicalAxis aAxis, + Prop aProp) { + bool found; + nscoord val = mFrame->GetProperty(aProp, &found); + if (found) { + NS_ASSERTION(val != nscoord(0), "zero in this property is useless"); + LogicalSide side; + if (val > 0) { + side = MakeLogicalSide(aAxis, eLogicalEdgeStart); + } else { + side = MakeLogicalSide(aAxis, eLogicalEdgeEnd); + val = -val; + } + mComputedPadding.Side(side, wm) += val; + needPaddingProp = true; + if (aAxis == eLogicalAxisBlock && val > 0) { + // We have a baseline-adjusted block-axis start padding, so + // we need this to mark lines dirty when mIsBResize is true: + this->mFrame->AddStateBits(NS_FRAME_CONTAINS_RELATIVE_BSIZE); + } + } + }; + if (!aFlags.contains(ComputeSizeFlag::IsGridMeasuringReflow)) { + ApplyBaselinePadding(eLogicalAxisBlock, nsIFrame::BBaselinePadProperty()); + } + if (!aFlags.contains(ComputeSizeFlag::ShrinkWrap)) { + ApplyBaselinePadding(eLogicalAxisInline, nsIFrame::IBaselinePadProperty()); + } + + LogicalMargin border(wm); + if (mIsThemed) { + const LayoutDeviceIntMargin widgetBorder = + presContext->Theme()->GetWidgetBorder( + presContext->DeviceContext(), mFrame, disp->EffectiveAppearance()); + border = LogicalMargin( + wm, LayoutDevicePixel::ToAppUnits(widgetBorder, + presContext->AppUnitsPerDevPixel())); + } else if (mFrame->IsInSVGTextSubtree()) { + // Do nothing since the border local variable is initialized all zero. + } else if (aBorder) { // border is an input arg + border = *aBorder; + } else { + border = LogicalMargin(wm, mFrame->StyleBorder()->GetComputedBorder()); + } + SetComputedLogicalBorderPadding(wm, border + ComputedLogicalPadding(wm)); + + if (aFrameType == LayoutFrameType::Scrollbar) { + // scrollbars may have had their width or height smashed to zero + // by the associated scrollframe, in which case we must not report + // any padding or border. + nsSize size(mFrame->GetSize()); + if (size.width == 0 || size.height == 0) { + SetComputedLogicalPadding(wm, LogicalMargin(wm)); + SetComputedLogicalBorderPadding(wm, LogicalMargin(wm)); + } + } + + bool hasPaddingChange; + if (nsMargin* oldPadding = + mFrame->GetProperty(nsIFrame::UsedPaddingProperty())) { + // Note: If a padding change is already detectable without resolving the + // percentage, e.g. a padding is changing from 50px to 50%, + // nsIFrame::DidSetComputedStyle() will cache the old padding in + // UsedPaddingProperty(). + hasPaddingChange = *oldPadding != ComputedPhysicalPadding(); + } else { + // Our padding may have changed, but we can't tell at this point. + hasPaddingChange = needPaddingProp; + } + // Keep mHasPaddingChange bit set until we've done reflow. We'll clear it in + // nsIFrame::DidReflow() + mFrame->SetHasPaddingChange(mFrame->HasPaddingChange() || hasPaddingChange); + + ::UpdateProp(mFrame, nsIFrame::UsedPaddingProperty(), needPaddingProp, + ComputedPhysicalPadding()); +} + +// This code enforces section 10.3.3 of the CSS2 spec for this formula: +// +// 'margin-left' + 'border-left-width' + 'padding-left' + 'width' + +// 'padding-right' + 'border-right-width' + 'margin-right' +// = width of containing block +// +// Note: the width unit is not auto when this is called +void ReflowInput::CalculateBlockSideMargins() { + MOZ_ASSERT(!mFrame->IsTableFrame(), + "Inner table frame cannot have computed margins!"); + + // Calculations here are done in the containing block's writing mode, + // which is where margins will eventually be applied: we're calculating + // margins that will be used by the container in its inline direction, + // which in the case of an orthogonal contained block will correspond to + // the block direction of this reflow input. So in the orthogonal-flow + // case, "CalculateBlock*Side*Margins" will actually end up adjusting + // the BStart/BEnd margins; those are the "sides" of the block from its + // container's point of view. + WritingMode cbWM = + mCBReflowInput ? mCBReflowInput->GetWritingMode() : GetWritingMode(); + + nscoord availISizeCBWM = AvailableSize(cbWM).ISize(cbWM); + nscoord computedISizeCBWM = ComputedSize(cbWM).ISize(cbWM); + if (computedISizeCBWM == NS_UNCONSTRAINEDSIZE) { + // For orthogonal flows, where we found a parent orthogonal-limit + // for AvailableISize() in Init(), we don't have meaningful sizes to + // adjust. Act like the sum is already correct (below). + return; + } + + LAYOUT_WARN_IF_FALSE(NS_UNCONSTRAINEDSIZE != computedISizeCBWM && + NS_UNCONSTRAINEDSIZE != availISizeCBWM, + "have unconstrained inline-size; this should only " + "result from very large sizes, not attempts at " + "intrinsic inline-size calculation"); + + LogicalMargin margin = ComputedLogicalMargin(cbWM); + LogicalMargin borderPadding = ComputedLogicalBorderPadding(cbWM); + nscoord sum = margin.IStartEnd(cbWM) + borderPadding.IStartEnd(cbWM) + + computedISizeCBWM; + if (sum == availISizeCBWM) { + // The sum is already correct + return; + } + + // Determine the start and end margin values. The isize value + // remains constant while we do this. + + // Calculate how much space is available for margins + nscoord availMarginSpace = availISizeCBWM - sum; + + // If the available margin space is negative, then don't follow the + // usual overconstraint rules. + if (availMarginSpace < 0) { + margin.IEnd(cbWM) += availMarginSpace; + SetComputedLogicalMargin(cbWM, margin); + return; + } + + // The css2 spec clearly defines how block elements should behave + // in section 10.3.3. + const auto& styleSides = mStyleMargin->mMargin; + bool isAutoStartMargin = styleSides.GetIStart(cbWM).IsAuto(); + bool isAutoEndMargin = styleSides.GetIEnd(cbWM).IsAuto(); + if (!isAutoStartMargin && !isAutoEndMargin) { + // Neither margin is 'auto' so we're over constrained. Use the + // 'direction' property of the parent to tell which margin to + // ignore + // First check if there is an HTML alignment that we should honor + const StyleTextAlign* textAlign = + mParentReflowInput + ? &mParentReflowInput->mFrame->StyleText()->mTextAlign + : nullptr; + if (textAlign && (*textAlign == StyleTextAlign::MozLeft || + *textAlign == StyleTextAlign::MozCenter || + *textAlign == StyleTextAlign::MozRight)) { + if (mParentReflowInput->mWritingMode.IsBidiLTR()) { + isAutoStartMargin = *textAlign != StyleTextAlign::MozLeft; + isAutoEndMargin = *textAlign != StyleTextAlign::MozRight; + } else { + isAutoStartMargin = *textAlign != StyleTextAlign::MozRight; + isAutoEndMargin = *textAlign != StyleTextAlign::MozLeft; + } + } + // Otherwise apply the CSS rules, and ignore one margin by forcing + // it to 'auto', depending on 'direction'. + else { + isAutoEndMargin = true; + } + } + + // Logic which is common to blocks and tables + // The computed margins need not be zero because the 'auto' could come from + // overconstraint or from HTML alignment so values need to be accumulated + + if (isAutoStartMargin) { + if (isAutoEndMargin) { + // Both margins are 'auto' so the computed addition should be equal + nscoord forStart = availMarginSpace / 2; + margin.IStart(cbWM) += forStart; + margin.IEnd(cbWM) += availMarginSpace - forStart; + } else { + margin.IStart(cbWM) += availMarginSpace; + } + } else if (isAutoEndMargin) { + margin.IEnd(cbWM) += availMarginSpace; + } + SetComputedLogicalMargin(cbWM, margin); + + if (isAutoStartMargin || isAutoEndMargin) { + // Update the UsedMargin property if we were tracking it already. + nsMargin* propValue = mFrame->GetProperty(nsIFrame::UsedMarginProperty()); + if (propValue) { + *propValue = margin.GetPhysicalMargin(cbWM); + } + } +} + +// For "normal" we use the font's normal line height (em height + leading). +// If both internal leading and external leading specified by font itself are +// zeros, we should compensate this by creating extra (external) leading. +// This is necessary because without this compensation, normal line height might +// look too tight. +constexpr float kNormalLineHeightFactor = 1.2f; +static nscoord GetNormalLineHeight(nsFontMetrics* aFontMetrics) { + MOZ_ASSERT(aFontMetrics, "no font metrics"); + nscoord externalLeading = aFontMetrics->ExternalLeading(); + nscoord internalLeading = aFontMetrics->InternalLeading(); + nscoord emHeight = aFontMetrics->EmHeight(); + if (!internalLeading && !externalLeading) { + return NSToCoordRound(emHeight * kNormalLineHeightFactor); + } + return emHeight + internalLeading + externalLeading; +} + +static inline nscoord ComputeLineHeight(const StyleLineHeight& aLh, + const nsStyleFont& aRelativeToFont, + nsPresContext* aPresContext, + bool aIsVertical, nscoord aBlockBSize, + float aFontSizeInflation) { + if (aLh.IsLength()) { + nscoord result = aLh.AsLength().ToAppUnits(); + if (aFontSizeInflation != 1.0f) { + result = NSToCoordRound(result * aFontSizeInflation); + } + return result; + } + + if (aLh.IsNumber()) { + // For factor units the computed value of the line-height property + // is found by multiplying the factor by the font's computed size + // (adjusted for min-size prefs and text zoom). + return aRelativeToFont.mFont.size + .ScaledBy(aLh.AsNumber() * aFontSizeInflation) + .ToAppUnits(); + } + + MOZ_ASSERT(aLh.IsNormal() || aLh.IsMozBlockHeight()); + if (aLh.IsMozBlockHeight() && aBlockBSize != NS_UNCONSTRAINEDSIZE) { + return aBlockBSize; + } + + auto size = aRelativeToFont.mFont.size; + size.ScaleBy(aFontSizeInflation); + + if (aPresContext) { + RefPtr<nsFontMetrics> fm = nsLayoutUtils::GetMetricsFor( + aPresContext, aIsVertical, &aRelativeToFont, size, + /* aUseUserFontSet = */ true); + return GetNormalLineHeight(fm); + } + // If we don't have a pres context, use a 1.2em fallback. + size.ScaleBy(kNormalLineHeightFactor); + return size.ToAppUnits(); +} + +nscoord ReflowInput::GetLineHeight() const { + if (mLineHeight != NS_UNCONSTRAINEDSIZE) { + return mLineHeight; + } + + nscoord blockBSize = nsLayoutUtils::IsNonWrapperBlock(mFrame) + ? ComputedBSize() + : (mCBReflowInput ? mCBReflowInput->ComputedBSize() + : NS_UNCONSTRAINEDSIZE); + mLineHeight = CalcLineHeight(*mFrame->Style(), mFrame->PresContext(), + mFrame->GetContent(), blockBSize, + nsLayoutUtils::FontSizeInflationFor(mFrame)); + return mLineHeight; +} + +void ReflowInput::SetLineHeight(nscoord aLineHeight) { + MOZ_ASSERT(aLineHeight >= 0, "aLineHeight must be >= 0!"); + + if (mLineHeight != aLineHeight) { + mLineHeight = aLineHeight; + // Setting used line height can change a frame's block-size if mFrame's + // block-size behaves as auto. + InitResizeFlags(mFrame->PresContext(), mFrame->Type()); + } +} + +/* static */ +nscoord ReflowInput::CalcLineHeight(const ComputedStyle& aStyle, + nsPresContext* aPresContext, + const nsIContent* aContent, + nscoord aBlockBSize, + float aFontSizeInflation) { + const StyleLineHeight& lh = aStyle.StyleText()->mLineHeight; + WritingMode wm(&aStyle); + const bool vertical = wm.IsVertical() && !wm.IsSideways(); + return CalcLineHeight(lh, *aStyle.StyleFont(), aPresContext, vertical, + aContent, aBlockBSize, aFontSizeInflation); +} + +nscoord ReflowInput::CalcLineHeight( + const StyleLineHeight& aLh, const nsStyleFont& aRelativeToFont, + nsPresContext* aPresContext, bool aIsVertical, const nsIContent* aContent, + nscoord aBlockBSize, float aFontSizeInflation) { + nscoord lineHeight = + ComputeLineHeight(aLh, aRelativeToFont, aPresContext, aIsVertical, + aBlockBSize, aFontSizeInflation); + + NS_ASSERTION(lineHeight >= 0, "ComputeLineHeight screwed up"); + + const auto* input = HTMLInputElement::FromNodeOrNull(aContent); + if (input && input->IsSingleLineTextControl()) { + // For Web-compatibility, single-line text input elements cannot + // have a line-height smaller than 'normal'. + if (!aLh.IsNormal()) { + nscoord normal = ComputeLineHeight( + StyleLineHeight::Normal(), aRelativeToFont, aPresContext, aIsVertical, + aBlockBSize, aFontSizeInflation); + if (lineHeight < normal) { + lineHeight = normal; + } + } + } + + return lineHeight; +} + +bool SizeComputationInput::ComputeMargin(WritingMode aCBWM, + nscoord aPercentBasis, + LayoutFrameType aFrameType) { + // SVG text frames have no margin. + if (mFrame->IsInSVGTextSubtree()) { + return false; + } + + if (aFrameType == LayoutFrameType::Table) { + // Table frame's margin is inherited to the table wrapper frame via the + // ::-moz-table-wrapper rule in ua.css, so don't set any margins for it. + SetComputedLogicalMargin(mWritingMode, LogicalMargin(mWritingMode)); + return false; + } + + // If style style can provide us the margin directly, then use it. + const nsStyleMargin* styleMargin = mFrame->StyleMargin(); + + nsMargin margin; + const bool isCBDependent = !styleMargin->GetMargin(margin); + if (isCBDependent) { + // We have to compute the value. Note that this calculation is + // performed according to the writing mode of the containing block + // (http://dev.w3.org/csswg/css-writing-modes-3/#orthogonal-flows) + if (aPercentBasis == NS_UNCONSTRAINEDSIZE) { + aPercentBasis = 0; + } + LogicalMargin m(aCBWM); + m.IStart(aCBWM) = nsLayoutUtils::ComputeCBDependentValue( + aPercentBasis, styleMargin->mMargin.GetIStart(aCBWM)); + m.IEnd(aCBWM) = nsLayoutUtils::ComputeCBDependentValue( + aPercentBasis, styleMargin->mMargin.GetIEnd(aCBWM)); + + m.BStart(aCBWM) = nsLayoutUtils::ComputeCBDependentValue( + aPercentBasis, styleMargin->mMargin.GetBStart(aCBWM)); + m.BEnd(aCBWM) = nsLayoutUtils::ComputeCBDependentValue( + aPercentBasis, styleMargin->mMargin.GetBEnd(aCBWM)); + + SetComputedLogicalMargin(aCBWM, m); + } else { + SetComputedLogicalMargin(mWritingMode, LogicalMargin(mWritingMode, margin)); + } + + // ... but font-size-inflation-based margin adjustment uses the + // frame's writing mode + nscoord marginAdjustment = FontSizeInflationListMarginAdjustment(mFrame); + + if (marginAdjustment > 0) { + LogicalMargin m = ComputedLogicalMargin(mWritingMode); + m.IStart(mWritingMode) += marginAdjustment; + SetComputedLogicalMargin(mWritingMode, m); + } + + return isCBDependent; +} + +bool SizeComputationInput::ComputePadding(WritingMode aCBWM, + nscoord aPercentBasis, + LayoutFrameType aFrameType) { + // If style can provide us the padding directly, then use it. + const nsStylePadding* stylePadding = mFrame->StylePadding(); + nsMargin padding; + bool isCBDependent = !stylePadding->GetPadding(padding); + // a table row/col group, row/col doesn't have padding + // XXXldb Neither do border-collapse tables. + if (LayoutFrameType::TableRowGroup == aFrameType || + LayoutFrameType::TableColGroup == aFrameType || + LayoutFrameType::TableRow == aFrameType || + LayoutFrameType::TableCol == aFrameType) { + SetComputedLogicalPadding(mWritingMode, LogicalMargin(mWritingMode)); + } else if (isCBDependent) { + // We have to compute the value. This calculation is performed + // according to the writing mode of the containing block + // (http://dev.w3.org/csswg/css-writing-modes-3/#orthogonal-flows) + // clamp negative calc() results to 0 + if (aPercentBasis == NS_UNCONSTRAINEDSIZE) { + aPercentBasis = 0; + } + LogicalMargin p(aCBWM); + p.IStart(aCBWM) = std::max( + 0, nsLayoutUtils::ComputeCBDependentValue( + aPercentBasis, stylePadding->mPadding.GetIStart(aCBWM))); + p.IEnd(aCBWM) = + std::max(0, nsLayoutUtils::ComputeCBDependentValue( + aPercentBasis, stylePadding->mPadding.GetIEnd(aCBWM))); + + p.BStart(aCBWM) = std::max( + 0, nsLayoutUtils::ComputeCBDependentValue( + aPercentBasis, stylePadding->mPadding.GetBStart(aCBWM))); + p.BEnd(aCBWM) = + std::max(0, nsLayoutUtils::ComputeCBDependentValue( + aPercentBasis, stylePadding->mPadding.GetBEnd(aCBWM))); + + SetComputedLogicalPadding(aCBWM, p); + } else { + SetComputedLogicalPadding(mWritingMode, + LogicalMargin(mWritingMode, padding)); + } + return isCBDependent; +} + +void ReflowInput::ComputeMinMaxValues(const LogicalSize& aCBSize) { + WritingMode wm = GetWritingMode(); + + const auto& minISize = mStylePosition->MinISize(wm); + const auto& maxISize = mStylePosition->MaxISize(wm); + const auto& minBSize = mStylePosition->MinBSize(wm); + const auto& maxBSize = mStylePosition->MaxBSize(wm); + + LogicalSize minWidgetSize(wm); + if (mIsThemed) { + nsPresContext* pc = mFrame->PresContext(); + const LayoutDeviceIntSize widget = pc->Theme()->GetMinimumWidgetSize( + pc, mFrame, mStyleDisplay->EffectiveAppearance()); + + // Convert themed widget's physical dimensions to logical coords. + minWidgetSize = { + wm, LayoutDeviceIntSize::ToAppUnits(widget, pc->AppUnitsPerDevPixel())}; + + // GetMinimumWidgetSize() returns border-box; we need content-box. + minWidgetSize -= ComputedLogicalBorderPadding(wm).Size(wm); + } + + // NOTE: min-width:auto resolves to 0, except on a flex item. (But + // even there, it's supposed to be ignored (i.e. treated as 0) until + // the flex container explicitly resolves & considers it.) + if (minISize.IsAuto()) { + SetComputedMinISize(0); + } else { + SetComputedMinISize( + ComputeISizeValue(aCBSize, mStylePosition->mBoxSizing, minISize)); + } + + if (mIsThemed) { + SetComputedMinISize(std::max(ComputedMinISize(), minWidgetSize.ISize(wm))); + } + + if (maxISize.IsNone()) { + // Specified value of 'none' + SetComputedMaxISize(NS_UNCONSTRAINEDSIZE); + } else { + SetComputedMaxISize( + ComputeISizeValue(aCBSize, mStylePosition->mBoxSizing, maxISize)); + } + + // If the computed value of 'min-width' is greater than the value of + // 'max-width', 'max-width' is set to the value of 'min-width' + if (ComputedMinISize() > ComputedMaxISize()) { + SetComputedMaxISize(ComputedMinISize()); + } + + // Check for percentage based values and a containing block height that + // depends on the content height. Treat them like the initial value. + // Likewise, check for calc() with percentages on internal table elements; + // that's treated as the initial value too. + const bool isInternalTableFrame = IsInternalTableFrame(); + const nscoord& bPercentageBasis = aCBSize.BSize(wm); + auto BSizeBehavesAsInitialValue = [&](const auto& aBSize) { + if (nsLayoutUtils::IsAutoBSize(aBSize, bPercentageBasis)) { + return true; + } + if (isInternalTableFrame) { + return aBSize.HasLengthAndPercentage(); + } + return false; + }; + + // NOTE: min-height:auto resolves to 0, except on a flex item. (But + // even there, it's supposed to be ignored (i.e. treated as 0) until + // the flex container explicitly resolves & considers it.) + if (BSizeBehavesAsInitialValue(minBSize)) { + SetComputedMinBSize(0); + } else { + SetComputedMinBSize(ComputeBSizeValue(bPercentageBasis, + mStylePosition->mBoxSizing, + minBSize.AsLengthPercentage())); + } + + if (mIsThemed) { + SetComputedMinBSize(std::max(ComputedMinBSize(), minWidgetSize.BSize(wm))); + } + + if (BSizeBehavesAsInitialValue(maxBSize)) { + // Specified value of 'none' + SetComputedMaxBSize(NS_UNCONSTRAINEDSIZE); + } else { + SetComputedMaxBSize(ComputeBSizeValue(bPercentageBasis, + mStylePosition->mBoxSizing, + maxBSize.AsLengthPercentage())); + } + + // If the computed value of 'min-height' is greater than the value of + // 'max-height', 'max-height' is set to the value of 'min-height' + if (ComputedMinBSize() > ComputedMaxBSize()) { + SetComputedMaxBSize(ComputedMinBSize()); + } +} + +bool ReflowInput::IsInternalTableFrame() const { + return mFrame->IsTableRowGroupFrame() || mFrame->IsTableColGroupFrame() || + mFrame->IsTableRowFrame() || mFrame->IsTableCellFrame(); +} |