1 files changed, 392 insertions, 0 deletions
diff --git a/layout/generic/nsFirstLetterFrame.cpp b/layout/generic/nsFirstLetterFrame.cpp
new file mode 100644
index 0000000000..220bf9fc4c
--- /dev/null
+++ b/layout/generic/nsFirstLetterFrame.cpp
@@ -0,0 +1,392 @@
+/* -*- 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/. */
+
+/* rendering object for CSS :first-letter pseudo-element */
+
+#include "nsFirstLetterFrame.h"
+#include "nsPresContext.h"
+#include "nsPresContextInlines.h"
+#include "mozilla/ComputedStyle.h"
+#include "mozilla/PresShell.h"
+#include "mozilla/PresShellInlines.h"
+#include "mozilla/RestyleManager.h"
+#include "mozilla/ServoStyleSet.h"
+#include "nsIContent.h"
+#include "nsLayoutUtils.h"
+#include "nsLineLayout.h"
+#include "nsGkAtoms.h"
+#include "nsFrameManager.h"
+#include "nsPlaceholderFrame.h"
+#include "nsCSSFrameConstructor.h"
+
+using namespace mozilla;
+using namespace mozilla::layout;
+
+nsFirstLetterFrame* NS_NewFirstLetterFrame(PresShell* aPresShell,
+                                           ComputedStyle* aStyle) {
+  return new (aPresShell)
+      nsFirstLetterFrame(aStyle, aPresShell->GetPresContext());
+}
+
+NS_IMPL_FRAMEARENA_HELPERS(nsFirstLetterFrame)
+
+NS_QUERYFRAME_HEAD(nsFirstLetterFrame)
+  NS_QUERYFRAME_ENTRY(nsFirstLetterFrame)
+NS_QUERYFRAME_TAIL_INHERITING(nsContainerFrame)
+
+#ifdef DEBUG_FRAME_DUMP
+nsresult nsFirstLetterFrame::GetFrameName(nsAString& aResult) const {
+  return MakeFrameName(u"Letter"_ns, aResult);
+}
+#endif
+
+void nsFirstLetterFrame::BuildDisplayList(nsDisplayListBuilder* aBuilder,
+                                          const nsDisplayListSet& aLists) {
+  BuildDisplayListForInline(aBuilder, aLists);
+}
+
+void nsFirstLetterFrame::Init(nsIContent* aContent, nsContainerFrame* aParent,
+                              nsIFrame* aPrevInFlow) {
+  RefPtr<ComputedStyle> newSC;
+  if (aPrevInFlow) {
+    // Get proper ComputedStyle for ourselves.  We're creating the frame
+    // that represents everything *except* the first letter, so just create
+    // a ComputedStyle that inherits from our style parent, with no extra rules.
+    nsIFrame* styleParent =
+        CorrectStyleParentFrame(aParent, PseudoStyleType::firstLetter);
+    ComputedStyle* parentComputedStyle = styleParent->Style();
+    newSC = PresContext()->StyleSet()->ResolveStyleForFirstLetterContinuation(
+        parentComputedStyle);
+    SetComputedStyleWithoutNotification(newSC);
+  }
+
+  nsContainerFrame::Init(aContent, aParent, aPrevInFlow);
+}
+
+void nsFirstLetterFrame::SetInitialChildList(ChildListID aListID,
+                                             nsFrameList& aChildList) {
+  MOZ_ASSERT(aListID == kPrincipalList,
+             "Principal child list is the only "
+             "list that nsFirstLetterFrame should set via this function");
+  for (nsIFrame* f : aChildList) {
+    MOZ_ASSERT(f->GetParent() == this, "Unexpected parent");
+    MOZ_ASSERT(f->IsTextFrame(),
+               "We should not have kids that are containers!");
+    nsLayoutUtils::MarkDescendantsDirty(f);  // Drops cached textruns
+  }
+
+  mFrames.SetFrames(aChildList);
+}
+
+nsresult nsFirstLetterFrame::GetChildFrameContainingOffset(
+    int32_t inContentOffset, bool inHint, int32_t* outFrameContentOffset,
+    nsIFrame** outChildFrame) {
+  nsIFrame* kid = mFrames.FirstChild();
+  if (kid) {
+    return kid->GetChildFrameContainingOffset(
+        inContentOffset, inHint, outFrameContentOffset, outChildFrame);
+  } else {
+    return nsIFrame::GetChildFrameContainingOffset(
+        inContentOffset, inHint, outFrameContentOffset, outChildFrame);
+  }
+}
+
+// Needed for non-floating first-letter frames and for the continuations
+// following the first-letter that we also use nsFirstLetterFrame for.
+/* virtual */
+void nsFirstLetterFrame::AddInlineMinISize(
+    gfxContext* aRenderingContext, nsIFrame::InlineMinISizeData* aData) {
+  DoInlineIntrinsicISize(aRenderingContext, aData,
+                         IntrinsicISizeType::MinISize);
+}
+
+// Needed for non-floating first-letter frames and for the continuations
+// following the first-letter that we also use nsFirstLetterFrame for.
+/* virtual */
+void nsFirstLetterFrame::AddInlinePrefISize(
+    gfxContext* aRenderingContext, nsIFrame::InlinePrefISizeData* aData) {
+  DoInlineIntrinsicISize(aRenderingContext, aData,
+                         IntrinsicISizeType::PrefISize);
+  aData->mLineIsEmpty = false;
+}
+
+// Needed for floating first-letter frames.
+/* virtual */
+nscoord nsFirstLetterFrame::GetMinISize(gfxContext* aRenderingContext) {
+  return nsLayoutUtils::MinISizeFromInline(this, aRenderingContext);
+}
+
+// Needed for floating first-letter frames.
+/* virtual */
+nscoord nsFirstLetterFrame::GetPrefISize(gfxContext* aRenderingContext) {
+  return nsLayoutUtils::PrefISizeFromInline(this, aRenderingContext);
+}
+
+/* virtual */
+nsIFrame::SizeComputationResult nsFirstLetterFrame::ComputeSize(
+    gfxContext* aRenderingContext, WritingMode aWM, const LogicalSize& aCBSize,
+    nscoord aAvailableISize, const LogicalSize& aMargin,
+    const LogicalSize& aBorderPadding, ComputeSizeFlags aFlags) {
+  if (GetPrevInFlow()) {
+    // We're wrapping the text *after* the first letter, so behave like an
+    // inline frame.
+    return {LogicalSize(aWM, NS_UNCONSTRAINEDSIZE, NS_UNCONSTRAINEDSIZE),
+            AspectRatioUsage::None};
+  }
+  return nsContainerFrame::ComputeSize(aRenderingContext, aWM, aCBSize,
+                                       aAvailableISize, aMargin, aBorderPadding,
+                                       aFlags);
+}
+
+void nsFirstLetterFrame::Reflow(nsPresContext* aPresContext,
+                                ReflowOutput& aMetrics,
+                                const ReflowInput& aReflowInput,
+                                nsReflowStatus& aReflowStatus) {
+  MarkInReflow();
+  DO_GLOBAL_REFLOW_COUNT("nsFirstLetterFrame");
+  DISPLAY_REFLOW(aPresContext, this, aReflowInput, aMetrics, aReflowStatus);
+  MOZ_ASSERT(aReflowStatus.IsEmpty(),
+             "Caller should pass a fresh reflow status!");
+
+  // Grab overflow list
+  DrainOverflowFrames(aPresContext);
+
+  nsIFrame* kid = mFrames.FirstChild();
+
+  // Setup reflow input for our child
+  WritingMode wm = aReflowInput.GetWritingMode();
+  LogicalSize availSize = aReflowInput.AvailableSize();
+  const auto bp = aReflowInput.ComputedLogicalBorderPadding(wm);
+  NS_ASSERTION(availSize.ISize(wm) != NS_UNCONSTRAINEDSIZE,
+               "should no longer use unconstrained inline size");
+  availSize.ISize(wm) -= bp.IStartEnd(wm);
+  if (NS_UNCONSTRAINEDSIZE != availSize.BSize(wm)) {
+    availSize.BSize(wm) -= bp.BStartEnd(wm);
+  }
+
+  WritingMode lineWM = aMetrics.GetWritingMode();
+  ReflowOutput kidMetrics(lineWM);
+
+  // Reflow the child
+  if (!aReflowInput.mLineLayout) {
+    // When there is no lineLayout provided, we provide our own. The
+    // only time that the first-letter-frame is not reflowing in a
+    // line context is when its floating.
+    WritingMode kidWritingMode = WritingModeForLine(wm, kid);
+    LogicalSize kidAvailSize = availSize.ConvertTo(kidWritingMode, wm);
+    ReflowInput rs(aPresContext, aReflowInput, kid, kidAvailSize);
+    nsLineLayout ll(aPresContext, nullptr, &aReflowInput, nullptr, nullptr);
+
+    ll.BeginLineReflow(
+        bp.IStart(wm), bp.BStart(wm), availSize.ISize(wm), NS_UNCONSTRAINEDSIZE,
+        false, true, kidWritingMode,
+        nsSize(aReflowInput.AvailableWidth(), aReflowInput.AvailableHeight()));
+    rs.mLineLayout = &ll;
+    ll.SetInFirstLetter(true);
+    ll.SetFirstLetterStyleOK(true);
+
+    kid->Reflow(aPresContext, kidMetrics, rs, aReflowStatus);
+
+    ll.EndLineReflow();
+    ll.SetInFirstLetter(false);
+
+    // In the floating first-letter case, we need to set this ourselves;
+    // nsLineLayout::BeginSpan will set it in the other case
+    mBaseline = kidMetrics.BlockStartAscent();
+
+    // Place and size the child and update the output metrics
+    LogicalSize convertedSize = kidMetrics.Size(wm);
+    kid->SetRect(nsRect(bp.IStart(wm), bp.BStart(wm), convertedSize.ISize(wm),
+                        convertedSize.BSize(wm)));
+    kid->FinishAndStoreOverflow(&kidMetrics, rs.mStyleDisplay);
+    kid->DidReflow(aPresContext, nullptr);
+
+    convertedSize.ISize(wm) += bp.IStartEnd(wm);
+    convertedSize.BSize(wm) += bp.BStartEnd(wm);
+    aMetrics.SetSize(wm, convertedSize);
+    aMetrics.SetBlockStartAscent(kidMetrics.BlockStartAscent() + bp.BStart(wm));
+
+    // Ensure that the overflow rect contains the child textframe's
+    // overflow rect.
+    // Note that if this is floating, the overline/underline drawable
+    // area is in the overflow rect of the child textframe.
+    aMetrics.UnionOverflowAreasWithDesiredBounds();
+    ConsiderChildOverflow(aMetrics.mOverflowAreas, kid);
+
+    FinishAndStoreOverflow(&aMetrics, aReflowInput.mStyleDisplay);
+  } else {
+    // Pretend we are a span and reflow the child frame
+    nsLineLayout* ll = aReflowInput.mLineLayout;
+    bool pushedFrame;
+
+    ll->SetInFirstLetter(Style()->GetPseudoType() ==
+                         PseudoStyleType::firstLetter);
+    ll->BeginSpan(this, &aReflowInput, bp.IStart(wm), availSize.ISize(wm),
+                  &mBaseline);
+    ll->ReflowFrame(kid, aReflowStatus, &kidMetrics, pushedFrame);
+    NS_ASSERTION(lineWM.IsVertical() == wm.IsVertical(),
+                 "we're assuming we can mix sizes between lineWM and wm "
+                 "since we shouldn't have orthogonal writing modes within "
+                 "a line.");
+    aMetrics.ISize(lineWM) = ll->EndSpan(this) + bp.IStartEnd(wm);
+    ll->SetInFirstLetter(false);
+
+    if (mComputedStyle->StyleTextReset()->mInitialLetterSize != 0.0f) {
+      aMetrics.SetBlockStartAscent(kidMetrics.BlockStartAscent() +
+                                   bp.BStart(wm));
+      aMetrics.BSize(lineWM) = kidMetrics.BSize(lineWM) + bp.BStartEnd(wm);
+    } else {
+      nsLayoutUtils::SetBSizeFromFontMetrics(this, aMetrics, bp, lineWM, wm);
+    }
+  }
+
+  if (!aReflowStatus.IsInlineBreakBefore()) {
+    // Create a continuation or remove existing continuations based on
+    // the reflow completion status.
+    if (aReflowStatus.IsComplete()) {
+      if (aReflowInput.mLineLayout) {
+        aReflowInput.mLineLayout->SetFirstLetterStyleOK(false);
+      }
+      nsIFrame* kidNextInFlow = kid->GetNextInFlow();
+      if (kidNextInFlow) {
+        // Remove all of the childs next-in-flows
+        kidNextInFlow->GetParent()->DeleteNextInFlowChild(kidNextInFlow, true);
+      }
+    } else {
+      // Create a continuation for the child frame if it doesn't already
+      // have one.
+      if (!IsFloating()) {
+        CreateNextInFlow(kid);
+        // And then push it to our overflow list
+        nsFrameList overflow = mFrames.RemoveFramesAfter(kid);
+        if (overflow.NotEmpty()) {
+          SetOverflowFrames(std::move(overflow));
+        }
+      } else if (!kid->GetNextInFlow()) {
+        // For floating first letter frames (if a continuation wasn't already
+        // created for us) we need to put the continuation with the rest of the
+        // text that the first letter frame was made out of.
+        nsIFrame* continuation;
+        CreateContinuationForFloatingParent(kid, &continuation, true);
+      }
+    }
+  }
+
+  NS_FRAME_SET_TRUNCATION(aReflowStatus, aReflowInput, aMetrics);
+}
+
+/* virtual */
+bool nsFirstLetterFrame::CanContinueTextRun() const {
+  // We can continue a text run through a first-letter frame.
+  return true;
+}
+
+void nsFirstLetterFrame::CreateContinuationForFloatingParent(
+    nsIFrame* aChild, nsIFrame** aContinuation, bool aIsFluid) {
+  NS_ASSERTION(IsFloating(),
+               "can only call this on floating first letter frames");
+  MOZ_ASSERT(aContinuation, "bad args");
+
+  *aContinuation = nullptr;
+
+  mozilla::PresShell* presShell = PresShell();
+  nsPlaceholderFrame* placeholderFrame = GetPlaceholderFrame();
+  nsContainerFrame* parent = placeholderFrame->GetParent();
+
+  nsIFrame* continuation = presShell->FrameConstructor()->CreateContinuingFrame(
+      aChild, parent, aIsFluid);
+
+  // The continuation will have gotten the first letter style from its
+  // prev continuation, so we need to repair the ComputedStyle so it
+  // doesn't have the first letter styling.
+  //
+  // Note that getting parent frame's ComputedStyle is different from getting
+  // this frame's ComputedStyle's parent in the presence of ::first-line,
+  // which we do want the continuation to inherit from.
+  ComputedStyle* parentSC = parent->Style();
+  if (parentSC) {
+    RefPtr<ComputedStyle> newSC;
+    newSC =
+        presShell->StyleSet()->ResolveStyleForFirstLetterContinuation(parentSC);
+    continuation->SetComputedStyle(newSC);
+    nsLayoutUtils::MarkDescendantsDirty(continuation);
+  }
+
+  // XXX Bidi may not be involved but we have to use the list name
+  // kNoReflowPrincipalList because this is just like creating a continuation
+  // except we have to insert it in a different place and we don't want a
+  // reflow command to try to be issued.
+  nsFrameList temp(continuation, continuation);
+  parent->InsertFrames(kNoReflowPrincipalList, placeholderFrame, nullptr, temp);
+
+  *aContinuation = continuation;
+}
+
+void nsFirstLetterFrame::DrainOverflowFrames(nsPresContext* aPresContext) {
+  // Check for an overflow list with our prev-in-flow
+  nsFirstLetterFrame* prevInFlow = (nsFirstLetterFrame*)GetPrevInFlow();
+  if (prevInFlow) {
+    AutoFrameListPtr overflowFrames(aPresContext,
+                                    prevInFlow->StealOverflowFrames());
+    if (overflowFrames) {
+      NS_ASSERTION(mFrames.IsEmpty(), "bad overflow list");
+
+      // When pushing and pulling frames we need to check for whether any
+      // views need to be reparented.
+      nsContainerFrame::ReparentFrameViewList(*overflowFrames, prevInFlow,
+                                              this);
+      mFrames.InsertFrames(this, nullptr, *overflowFrames);
+    }
+  }
+
+  // It's also possible that we have an overflow list for ourselves
+  AutoFrameListPtr overflowFrames(aPresContext, StealOverflowFrames());
+  if (overflowFrames) {
+    NS_ASSERTION(mFrames.NotEmpty(), "overflow list w/o frames");
+    mFrames.AppendFrames(nullptr, *overflowFrames);
+  }
+
+  // Now repair our first frames ComputedStyle (since we only reflow
+  // one frame there is no point in doing any other ones until they
+  // are reflowed)
+  nsIFrame* kid = mFrames.FirstChild();
+  if (kid) {
+    nsIContent* kidContent = kid->GetContent();
+    if (kidContent) {
+      NS_ASSERTION(kidContent->IsText(), "should contain only text nodes");
+      ComputedStyle* parentSC;
+      if (prevInFlow) {
+        // This is for the rest of the content not in the first-letter.
+        nsIFrame* styleParent =
+            CorrectStyleParentFrame(GetParent(), PseudoStyleType::firstLetter);
+        parentSC = styleParent->Style();
+      } else {
+        // And this for the first-letter style.
+        parentSC = mComputedStyle;
+      }
+      RefPtr<ComputedStyle> sc =
+          aPresContext->StyleSet()->ResolveStyleForText(kidContent, parentSC);
+      kid->SetComputedStyle(sc);
+      nsLayoutUtils::MarkDescendantsDirty(kid);
+    }
+  }
+}
+
+nscoord nsFirstLetterFrame::GetLogicalBaseline(WritingMode aWritingMode) const {
+  return mBaseline;
+}
+
+LogicalSides nsFirstLetterFrame::GetLogicalSkipSides() const {
+  if (GetPrevContinuation()) {
+    // We shouldn't get calls to GetSkipSides for later continuations since
+    // they have separate ComputedStyles with initial values for all the
+    // properties that could trigger a call to GetSkipSides.  Then again,
+    // it's not really an error to call GetSkipSides on any frame, so
+    // that's why we handle it properly.
+    return LogicalSides(mWritingMode, eLogicalSideBitsAll);
+  }
+  return LogicalSides(mWritingMode);  // first continuation displays all sides
+}