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/* -*- 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 */
#include "nsMathMLSelectedFrame.h"
#include "nsDisplayList.h"
using namespace mozilla;
nsMathMLSelectedFrame::~nsMathMLSelectedFrame() = default;
nsMathMLSelectedFrame::TransmitAutomaticData() {
// Note that to determine space-like and embellished op properties:
// - <semantics> behaves the same as <maction>
// - <annotation-xml> behaves the same as <mrow>
// The REC defines the following element to be space-like:
// * an maction element whose selected sub-expression exists and is
// space-like;
nsIMathMLFrame* mathMLFrame = do_QueryFrame(mSelectedFrame);
if (mathMLFrame && mathMLFrame->IsSpaceLike()) {
mPresentationData.flags |= NS_MATHML_SPACE_LIKE;
} else {
mPresentationData.flags &= ~NS_MATHML_SPACE_LIKE;
// The REC defines the following element to be an embellished operator:
// * an maction element whose selected sub-expression exists and is an
// embellished operator;
mPresentationData.baseFrame = mSelectedFrame;
GetEmbellishDataFrom(mSelectedFrame, mEmbellishData);
return NS_OK;
nsresult nsMathMLSelectedFrame::ChildListChanged(int32_t aModType) {
return nsMathMLContainerFrame::ChildListChanged(aModType);
void nsMathMLSelectedFrame::SetInitialChildList(ChildListID aListID,
nsFrameList&& aChildList) {
nsMathMLContainerFrame::SetInitialChildList(aListID, std::move(aChildList));
// This very first call to GetSelectedFrame() will cause us to be marked as an
// embellished operator if the selected child is an embellished operator
// Only paint the selected child...
void nsMathMLSelectedFrame::BuildDisplayList(nsDisplayListBuilder* aBuilder,
const nsDisplayListSet& aLists) {
// Report an error if something wrong was found in this frame.
// We can't call nsDisplayMathMLError from here,
// so ask nsMathMLContainerFrame to do the work for us.
if (NS_MATHML_HAS_ERROR(mPresentationData.flags)) {
nsMathMLContainerFrame::BuildDisplayList(aBuilder, aLists);
DisplayBorderBackgroundOutline(aBuilder, aLists);
nsIFrame* childFrame = GetSelectedFrame();
if (childFrame) {
// Put the child's background directly onto the content list
nsDisplayListSet set(aLists, aLists.Content());
// The children should be in content order
BuildDisplayListForChild(aBuilder, childFrame, set);
#if defined(DEBUG) && defined(SHOW_BOUNDING_BOX)
// visual debug
DisplayBoundingMetrics(aBuilder, this, mReference, mBoundingMetrics, aLists);
/* virtual */
nsIFrame::SizeComputationResult nsMathMLSelectedFrame::ComputeSize(
gfxContext* aRenderingContext, WritingMode aWM, const LogicalSize& aCBSize,
nscoord aAvailableISize, const LogicalSize& aMargin,
const LogicalSize& aBorderPadding, const StyleSizeOverrides& aSizeOverrides,
ComputeSizeFlags aFlags) {
nsIFrame* childFrame = GetSelectedFrame();
if (childFrame) {
// Delegate size computation to the child frame.
// Try to account for border/padding/margin on this frame and the child,
// though we don't really support them during reflow anyway...
const nscoord availableISize =
aAvailableISize - aBorderPadding.ISize(aWM) - aMargin.ISize(aWM);
const LogicalSize cbSize = aCBSize - aBorderPadding - aMargin;
SizeComputationInput offsetState(childFrame, aRenderingContext, aWM,
const auto bpSize = offsetState.ComputedLogicalBorderPadding(aWM).Size(aWM);
auto size = childFrame->ComputeSize(
aRenderingContext, aWM, cbSize, availableISize,
offsetState.ComputedLogicalMargin(aWM).Size(aWM), bpSize,
aSizeOverrides, aFlags);
return {size.mLogicalSize + bpSize, size.mAspectRatioUsage};
return {LogicalSize(aWM), AspectRatioUsage::None};
// Only reflow the selected child ...
void nsMathMLSelectedFrame::Reflow(nsPresContext* aPresContext,
ReflowOutput& aDesiredSize,
const ReflowInput& aReflowInput,
nsReflowStatus& aStatus) {
MOZ_ASSERT(aStatus.IsEmpty(), "Caller should pass a fresh reflow status!");
mPresentationData.flags &= ~NS_MATHML_ERROR;
mBoundingMetrics = nsBoundingMetrics();
nsIFrame* childFrame = GetSelectedFrame();
if (childFrame) {
WritingMode wm = childFrame->GetWritingMode();
LogicalSize availSize = aReflowInput.ComputedSize(wm);
ReflowInput childReflowInput(aPresContext, aReflowInput, childFrame,
ReflowChild(childFrame, aPresContext, aDesiredSize, childReflowInput,
SaveReflowAndBoundingMetricsFor(childFrame, aDesiredSize,
mBoundingMetrics = aDesiredSize.mBoundingMetrics;
FinalizeReflow(aReflowInput.mRenderingContext->GetDrawTarget(), aDesiredSize);
// Only place the selected child ...
/* virtual */
nsresult nsMathMLSelectedFrame::Place(DrawTarget* aDrawTarget,
bool aPlaceOrigin,
ReflowOutput& aDesiredSize) {
nsIFrame* childFrame = GetSelectedFrame();
if (mInvalidMarkup) {
// Calling PlaceForError when mathml.error_message_layout_for_invalid_markup
// is disabled causes assertion failures because nsMathMLSelectedFrame only
// performs layout of the selected child. However, this code is only reached
// when mathml.legacy_maction_and_semantics_implementations is enabled, so
// it is out the scope of the mrow fallback described in MathML Core and
// nsMathMLSelectedFrame will go away in the future. So for now let's
// continue to always layout this case as an 'invalid-markup' message.
return ReflowError(aDrawTarget, aDesiredSize);
mBoundingMetrics = nsBoundingMetrics();
if (childFrame) {
GetReflowAndBoundingMetricsFor(childFrame, aDesiredSize, mBoundingMetrics);
if (aPlaceOrigin) {
FinishReflowChild(childFrame, PresContext(), aDesiredSize, nullptr, 0, 0,
mReference.x = 0;
mReference.y = aDesiredSize.BlockStartAscent();
aDesiredSize.mBoundingMetrics = mBoundingMetrics;
return NS_OK;