The Tor Browser: layout/generic/TextOverflow.cpp@b8a032363ba2 (annotated)

layout/generic/TextOverflow.cpp@b8a032363ba2 (annotated)

layout/generic/TextOverflow.cpp

Thu, 22 Jan 2015 13:21:57 +0100

author: Michael Schloh von Bennewitz <michael@schloh.com>
date: Thu, 22 Jan 2015 13:21:57 +0100
branch: TOR_BUG_9701
changeset 15: b8a032363ba2
permissions: -rw-r--r--

Incorporate requested changes from Mozilla in review:
https://bugzilla.mozilla.org/show_bug.cgi?id=1123480#c6

 /* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
 /* vim: set shiftwidth=2 tabstop=8 autoindent cindent expandtab: */
 /* 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/. */
 #include "TextOverflow.h"
 #include <algorithm>
 // Please maintain alphabetical order below
 #include "nsBlockFrame.h"
 #include "nsCaret.h"
 #include "nsContentUtils.h"
 #include "nsCSSAnonBoxes.h"
 #include "nsGfxScrollFrame.h"
 #include "nsIScrollableFrame.h"
 #include "nsLayoutUtils.h"
 #include "nsPresContext.h"
 #include "nsRect.h"
 #include "nsRenderingContext.h"
 #include "nsTextFrame.h"
 #include "nsIFrameInlines.h"
 #include "mozilla/ArrayUtils.h"
 #include "mozilla/Likely.h"
 namespace mozilla {
 namespace css {
 class LazyReferenceRenderingContextGetterFromFrame MOZ_FINAL :
     public gfxFontGroup::LazyReferenceContextGetter {
 public:
   LazyReferenceRenderingContextGetterFromFrame(nsIFrame* aFrame)
     : mFrame(aFrame) {}
   virtual already_AddRefed<gfxContext> GetRefContext() MOZ_OVERRIDE
   {
     nsRefPtr<nsRenderingContext> rc =
       mFrame->PresContext()->PresShell()->CreateReferenceRenderingContext();
     nsRefPtr<gfxContext> ctx = rc->ThebesContext();
     return ctx.forget();
   }
 private:
   nsIFrame* mFrame;
 };
 static gfxTextRun*
 GetEllipsisTextRun(nsIFrame* aFrame)
 {
   nsRefPtr<nsFontMetrics> fm;
   nsLayoutUtils::GetFontMetricsForFrame(aFrame, getter_AddRefs(fm),
     nsLayoutUtils::FontSizeInflationFor(aFrame));
   LazyReferenceRenderingContextGetterFromFrame lazyRefContextGetter(aFrame);
   return fm->GetThebesFontGroup()->GetEllipsisTextRun(
       aFrame->PresContext()->AppUnitsPerDevPixel(), lazyRefContextGetter);
 }
 static nsIFrame*
 GetSelfOrNearestBlock(nsIFrame* aFrame)
 {
   return nsLayoutUtils::GetAsBlock(aFrame) ? aFrame :
          nsLayoutUtils::FindNearestBlockAncestor(aFrame);
 }
 // Return true if the frame is an atomic inline-level element.
 // It's not supposed to be called for block frames since we never
 // process block descendants for text-overflow.
 static bool
 IsAtomicElement(nsIFrame* aFrame, const nsIAtom* aFrameType)
 {
   NS_PRECONDITION(!nsLayoutUtils::GetAsBlock(aFrame) ||
                   !aFrame->IsBlockOutside(),
                   "unexpected block frame");
   NS_PRECONDITION(aFrameType != nsGkAtoms::placeholderFrame,
                   "unexpected placeholder frame");
   return !aFrame->IsFrameOfType(nsIFrame::eLineParticipant);
 }
 static bool
 IsFullyClipped(nsTextFrame* aFrame, nscoord aLeft, nscoord aRight,
                nscoord* aSnappedLeft, nscoord* aSnappedRight)
 {
   *aSnappedLeft = aLeft;
   *aSnappedRight = aRight;
   if (aLeft <= 0 && aRight <= 0) {
     return false;
   }
   return !aFrame->MeasureCharClippedText(aLeft, aRight,
                                          aSnappedLeft, aSnappedRight);
 }
 static bool
 IsHorizontalOverflowVisible(nsIFrame* aFrame)
 {
   NS_PRECONDITION(nsLayoutUtils::GetAsBlock(aFrame) != nullptr,
                   "expected a block frame");
   nsIFrame* f = aFrame;
   while (f && f->StyleContext()->GetPseudo() &&
          f->GetType() != nsGkAtoms::scrollFrame) {
     f = f->GetParent();
   }
   return !f || f->StyleDisplay()->mOverflowX == NS_STYLE_OVERFLOW_VISIBLE;
 }
 static void
 ClipMarker(const nsRect&                          aContentArea,
            const nsRect&                          aMarkerRect,
            DisplayListClipState::AutoSaveRestore& aClipState)
 {
   nscoord rightOverflow = aMarkerRect.XMost() - aContentArea.XMost();
   nsRect markerRect = aMarkerRect;
   if (rightOverflow > 0) {
     // Marker overflows on the right side (content width < marker width).
     markerRect.width -= rightOverflow;
     aClipState.ClipContentDescendants(markerRect);
   } else {
     nscoord leftOverflow = aContentArea.x - aMarkerRect.x;
     if (leftOverflow > 0) {
       // Marker overflows on the left side
       markerRect.width -= leftOverflow;
       markerRect.x += leftOverflow;
       aClipState.ClipContentDescendants(markerRect);
     }
   }
 }
 static void
 InflateLeft(nsRect* aRect, nscoord aDelta)
 {
   nscoord xmost = aRect->XMost();
   aRect->x -= aDelta;
   aRect->width = std::max(xmost - aRect->x, 0);
 }
 static void
 InflateRight(nsRect* aRect, nscoord aDelta)
 {
   aRect->width = std::max(aRect->width + aDelta, 0);
 }
 static bool
 IsFrameDescendantOfAny(nsIFrame* aChild,
                        const TextOverflow::FrameHashtable& aSetOfFrames,
                        nsIFrame* aCommonAncestor)
 {
   for (nsIFrame* f = aChild; f && f != aCommonAncestor;
        f = nsLayoutUtils::GetCrossDocParentFrame(f)) {
     if (aSetOfFrames.GetEntry(f)) {
       return true;
     }
   }
   return false;
 }
 class nsDisplayTextOverflowMarker : public nsDisplayItem
 {
 public:
   nsDisplayTextOverflowMarker(nsDisplayListBuilder* aBuilder, nsIFrame* aFrame,
                               const nsRect& aRect, nscoord aAscent,
                               const nsStyleTextOverflowSide* aStyle,
                               uint32_t aIndex)
     : nsDisplayItem(aBuilder, aFrame), mRect(aRect),
       mStyle(aStyle), mAscent(aAscent), mIndex(aIndex) {
     MOZ_COUNT_CTOR(nsDisplayTextOverflowMarker);
   }
 #ifdef NS_BUILD_REFCNT_LOGGING
   virtual ~nsDisplayTextOverflowMarker() {
     MOZ_COUNT_DTOR(nsDisplayTextOverflowMarker);
   }
 #endif
   virtual nsRect GetBounds(nsDisplayListBuilder* aBuilder,
                            bool* aSnap) MOZ_OVERRIDE {
     *aSnap = false;
     nsRect shadowRect =
       nsLayoutUtils::GetTextShadowRectsUnion(mRect, mFrame);
     return mRect.Union(shadowRect);
   }
   virtual void Paint(nsDisplayListBuilder* aBuilder,
                      nsRenderingContext* aCtx) MOZ_OVERRIDE;
   virtual uint32_t GetPerFrameKey() MOZ_OVERRIDE {
     return (mIndex << nsDisplayItem::TYPE_BITS) | nsDisplayItem::GetPerFrameKey();
   }
   void PaintTextToContext(nsRenderingContext* aCtx,
                           nsPoint aOffsetFromRect);
   NS_DISPLAY_DECL_NAME("TextOverflow", TYPE_TEXT_OVERFLOW)
 private:
   nsRect          mRect;   // in reference frame coordinates
   const nsStyleTextOverflowSide* mStyle;
   nscoord         mAscent; // baseline for the marker text in mRect
   uint32_t        mIndex;
 };
 static void
 PaintTextShadowCallback(nsRenderingContext* aCtx,
                         nsPoint aShadowOffset,
                         const nscolor& aShadowColor,
                         void* aData)
 {
   reinterpret_cast<nsDisplayTextOverflowMarker*>(aData)->
            PaintTextToContext(aCtx, aShadowOffset);
 }
 void
 nsDisplayTextOverflowMarker::Paint(nsDisplayListBuilder* aBuilder,
                                    nsRenderingContext*   aCtx)
 {
   nscolor foregroundColor =
     nsLayoutUtils::GetColor(mFrame, eCSSProperty_color);
   // Paint the text-shadows for the overflow marker
   nsLayoutUtils::PaintTextShadow(mFrame, aCtx, mRect, mVisibleRect,
                                  foregroundColor, PaintTextShadowCallback,
                                  (void*)this);
   aCtx->SetColor(foregroundColor);
   PaintTextToContext(aCtx, nsPoint(0, 0));
 }
 void
 nsDisplayTextOverflowMarker::PaintTextToContext(nsRenderingContext* aCtx,
                                                 nsPoint aOffsetFromRect)
 {
   gfxFloat y = nsLayoutUtils::GetSnappedBaselineY(mFrame, aCtx->ThebesContext(),
                                                   mRect.y, mAscent);
   nsPoint baselinePt(mRect.x, NSToCoordFloor(y));
   nsPoint pt = baselinePt + aOffsetFromRect;
   if (mStyle->mType == NS_STYLE_TEXT_OVERFLOW_ELLIPSIS) {
     gfxTextRun* textRun = GetEllipsisTextRun(mFrame);
     if (textRun) {
       NS_ASSERTION(!textRun->IsRightToLeft(),
                    "Ellipsis textruns should always be LTR!");
       gfxPoint gfxPt(pt.x, pt.y);
       textRun->Draw(aCtx->ThebesContext(), gfxPt, DrawMode::GLYPH_FILL,
 , textRun->GetLength(), nullptr, nullptr, nullptr);
     }
   } else {
     nsRefPtr<nsFontMetrics> fm;
     nsLayoutUtils::GetFontMetricsForFrame(mFrame, getter_AddRefs(fm),
       nsLayoutUtils::FontSizeInflationFor(mFrame));
     aCtx->SetFont(fm);
     nsLayoutUtils::DrawString(mFrame, aCtx, mStyle->mString.get(),
                               mStyle->mString.Length(), pt);
   }
 }
 void
 TextOverflow::Init(nsDisplayListBuilder*   aBuilder,
                    nsIFrame*               aBlockFrame)
 {
   mBuilder = aBuilder;
   mBlock = aBlockFrame;
   mContentArea = aBlockFrame->GetContentRectRelativeToSelf();
   mScrollableFrame = nsLayoutUtils::GetScrollableFrameFor(aBlockFrame);
   uint8_t direction = aBlockFrame->StyleVisibility()->mDirection;
   mBlockIsRTL = direction == NS_STYLE_DIRECTION_RTL;
   mAdjustForPixelSnapping = false;
 #ifdef MOZ_XUL
   if (!mScrollableFrame) {
     nsIAtom* pseudoType = aBlockFrame->StyleContext()->GetPseudo();
     if (pseudoType == nsCSSAnonBoxes::mozXULAnonymousBlock) {
       mScrollableFrame =
         nsLayoutUtils::GetScrollableFrameFor(aBlockFrame->GetParent());
       // nsXULScrollFrame::ClampAndSetBounds rounds to nearest pixels
       // for RTL blocks (also for overflow:hidden), so we need to move
       // the edges 1px outward in ExamineLineFrames to avoid triggering
       // a text-overflow marker in this case.
       mAdjustForPixelSnapping = mBlockIsRTL;
     }
   }
 #endif
   mCanHaveHorizontalScrollbar = false;
   if (mScrollableFrame) {
     mCanHaveHorizontalScrollbar =
       mScrollableFrame->GetScrollbarStyles().mHorizontal != NS_STYLE_OVERFLOW_HIDDEN;
     if (!mAdjustForPixelSnapping) {
       // Scrolling to the end position can leave some text still overflowing due
       // to pixel snapping behaviour in our scrolling code.
       mAdjustForPixelSnapping = mCanHaveHorizontalScrollbar;
     }
     mContentArea.MoveBy(mScrollableFrame->GetScrollPosition());
     nsIFrame* scrollFrame = do_QueryFrame(mScrollableFrame);
     scrollFrame->AddStateBits(NS_SCROLLFRAME_INVALIDATE_CONTENTS_ON_SCROLL);
   }
   const nsStyleTextReset* style = aBlockFrame->StyleTextReset();
   mLeft.Init(style->mTextOverflow.GetLeft(direction));
   mRight.Init(style->mTextOverflow.GetRight(direction));
   // The left/right marker string is setup in ExamineLineFrames when a line
   // has overflow on that side.
 }
 /* static */ TextOverflow*
 TextOverflow::WillProcessLines(nsDisplayListBuilder*   aBuilder,
                                nsIFrame*               aBlockFrame)
 {
   if (!CanHaveTextOverflow(aBuilder, aBlockFrame)) {
     return nullptr;
   }
   nsAutoPtr<TextOverflow> textOverflow(new TextOverflow);
   textOverflow->Init(aBuilder, aBlockFrame);
   return textOverflow.forget();
 }
 void
 TextOverflow::ExamineFrameSubtree(nsIFrame*       aFrame,
                                   const nsRect&   aContentArea,
                                   const nsRect&   aInsideMarkersArea,
                                   FrameHashtable* aFramesToHide,
                                   AlignmentEdges* aAlignmentEdges,
                                   bool*           aFoundVisibleTextOrAtomic,
                                   InnerClipEdges* aClippedMarkerEdges)
 {
   const nsIAtom* frameType = aFrame->GetType();
   if (frameType == nsGkAtoms::brFrame ||
       frameType == nsGkAtoms::placeholderFrame) {
     return;
   }
   const bool isAtomic = IsAtomicElement(aFrame, frameType);
   if (aFrame->StyleVisibility()->IsVisible()) {
     nsRect childRect = aFrame->GetScrollableOverflowRect() +
                        aFrame->GetOffsetTo(mBlock);
     bool overflowLeft = childRect.x < aContentArea.x;
     bool overflowRight = childRect.XMost() > aContentArea.XMost();
     if (overflowLeft) {
       mLeft.mHasOverflow = true;
     }
     if (overflowRight) {
       mRight.mHasOverflow = true;
     }
     if (isAtomic && ((mLeft.mActive && overflowLeft) ||
                      (mRight.mActive && overflowRight))) {
       aFramesToHide->PutEntry(aFrame);
     } else if (isAtomic || frameType == nsGkAtoms::textFrame) {
       AnalyzeMarkerEdges(aFrame, frameType, aInsideMarkersArea,
                          aFramesToHide, aAlignmentEdges,
                          aFoundVisibleTextOrAtomic,
                          aClippedMarkerEdges);
     }
   }
   if (isAtomic) {
     return;
   }
   nsIFrame* child = aFrame->GetFirstPrincipalChild();
   while (child) {
     ExamineFrameSubtree(child, aContentArea, aInsideMarkersArea,
                         aFramesToHide, aAlignmentEdges,
                         aFoundVisibleTextOrAtomic,
                         aClippedMarkerEdges);
     child = child->GetNextSibling();
   }
 }
 void
 TextOverflow::AnalyzeMarkerEdges(nsIFrame*       aFrame,
                                  const nsIAtom*  aFrameType,
                                  const nsRect&   aInsideMarkersArea,
                                  FrameHashtable* aFramesToHide,
                                  AlignmentEdges* aAlignmentEdges,
                                  bool*           aFoundVisibleTextOrAtomic,
                                  InnerClipEdges* aClippedMarkerEdges)
 {
   nsRect borderRect(aFrame->GetOffsetTo(mBlock), aFrame->GetSize());
   nscoord leftOverlap =
     std::max(aInsideMarkersArea.x - borderRect.x, 0);
   nscoord rightOverlap =
     std::max(borderRect.XMost() - aInsideMarkersArea.XMost(), 0);
   bool insideLeftEdge = aInsideMarkersArea.x <= borderRect.XMost();
   bool insideRightEdge = borderRect.x <= aInsideMarkersArea.XMost();
   if (leftOverlap > 0) {
     aClippedMarkerEdges->AccumulateLeft(borderRect);
     if (!mLeft.mActive) {
       leftOverlap = 0;
     }
   }
   if (rightOverlap > 0) {
     aClippedMarkerEdges->AccumulateRight(borderRect);
     if (!mRight.mActive) {
       rightOverlap = 0;
     }
   }
   if ((leftOverlap > 0 && insideLeftEdge) ||
       (rightOverlap > 0 && insideRightEdge)) {
     if (aFrameType == nsGkAtoms::textFrame) {
       if (aInsideMarkersArea.x < aInsideMarkersArea.XMost()) {
         // a clipped text frame and there is some room between the markers
         nscoord snappedLeft, snappedRight;
         bool isFullyClipped =
           IsFullyClipped(static_cast<nsTextFrame*>(aFrame),
                          leftOverlap, rightOverlap, &snappedLeft, &snappedRight);
         if (!isFullyClipped) {
           nsRect snappedRect = borderRect;
           if (leftOverlap > 0) {
             snappedRect.x += snappedLeft;
             snappedRect.width -= snappedLeft;
           }
           if (rightOverlap > 0) {
             snappedRect.width -= snappedRight;
           }
           aAlignmentEdges->Accumulate(snappedRect);
           *aFoundVisibleTextOrAtomic = true;
         }
       }
     } else {
       aFramesToHide->PutEntry(aFrame);
     }
   } else if (!insideLeftEdge || !insideRightEdge) {
     // frame is outside
     if (IsAtomicElement(aFrame, aFrameType)) {
       aFramesToHide->PutEntry(aFrame);
     }
   } else {
     // frame is inside
     aAlignmentEdges->Accumulate(borderRect);
     *aFoundVisibleTextOrAtomic = true;
   }
 }
 void
 TextOverflow::ExamineLineFrames(nsLineBox*      aLine,
                                 FrameHashtable* aFramesToHide,
                                 AlignmentEdges* aAlignmentEdges)
 {
   // No ellipsing for 'clip' style.
   bool suppressLeft = mLeft.mStyle->mType == NS_STYLE_TEXT_OVERFLOW_CLIP;
   bool suppressRight = mRight.mStyle->mType == NS_STYLE_TEXT_OVERFLOW_CLIP;
   if (mCanHaveHorizontalScrollbar) {
     nsPoint pos = mScrollableFrame->GetScrollPosition();
     nsRect scrollRange = mScrollableFrame->GetScrollRange();
     // No ellipsing when nothing to scroll to on that side (this includes
     // overflow:auto that doesn't trigger a horizontal scrollbar).
     if (pos.x <= scrollRange.x) {
       suppressLeft = true;
     }
     if (pos.x >= scrollRange.XMost()) {
       suppressRight = true;
     }
   }
   nsRect contentArea = mContentArea;
   const nscoord scrollAdjust = mAdjustForPixelSnapping ?
     mBlock->PresContext()->AppUnitsPerDevPixel() : 0;
   InflateLeft(&contentArea, scrollAdjust);
   InflateRight(&contentArea, scrollAdjust);
   nsRect lineRect = aLine->GetScrollableOverflowArea();
   const bool leftOverflow =
     !suppressLeft && lineRect.x < contentArea.x;
   const bool rightOverflow =
     !suppressRight && lineRect.XMost() > contentArea.XMost();
   if (!leftOverflow && !rightOverflow) {
     // The line does not overflow on a side we should ellipsize.
     return;
   }
   int pass = 0;
   bool retryEmptyLine = true;
   bool guessLeft = leftOverflow;
   bool guessRight = rightOverflow;
   mLeft.mActive = leftOverflow;
   mRight.mActive = rightOverflow;
   bool clippedLeftMarker = false;
   bool clippedRightMarker = false;
   do {
     // Setup marker strings as needed.
     if (guessLeft) {
       mLeft.SetupString(mBlock);
     }
     if (guessRight) {
       mRight.SetupString(mBlock);
     }
     // If there is insufficient space for both markers then keep the one on the
     // end side per the block's 'direction'.
     nscoord rightMarkerWidth = mRight.mActive ? mRight.mWidth : 0;
     nscoord leftMarkerWidth = mLeft.mActive ? mLeft.mWidth : 0;
     if (leftMarkerWidth && rightMarkerWidth &&
         leftMarkerWidth + rightMarkerWidth > contentArea.width) {
       if (mBlockIsRTL) {
         rightMarkerWidth = 0;
       } else {
         leftMarkerWidth = 0;
       }
     }
     // Calculate the area between the potential markers aligned at the
     // block's edge.
     nsRect insideMarkersArea = mContentArea;
     if (guessLeft) {
       InflateLeft(&insideMarkersArea, -leftMarkerWidth);
     }
     if (guessRight) {
       InflateRight(&insideMarkersArea, -rightMarkerWidth);
     }
     // Analyze the frames on aLine for the overflow situation at the content
     // edges and at the edges of the area between the markers.
     bool foundVisibleTextOrAtomic = false;
     int32_t n = aLine->GetChildCount();
     nsIFrame* child = aLine->mFirstChild;
     InnerClipEdges clippedMarkerEdges;
     for (; n-- > 0; child = child->GetNextSibling()) {
       ExamineFrameSubtree(child, contentArea, insideMarkersArea,
                           aFramesToHide, aAlignmentEdges,
                           &foundVisibleTextOrAtomic,
                           &clippedMarkerEdges);
     }
     if (!foundVisibleTextOrAtomic && retryEmptyLine) {
       aAlignmentEdges->mAssigned = false;
       aFramesToHide->Clear();
       pass = -1;
       if (mLeft.IsNeeded() && mLeft.mActive && !clippedLeftMarker) {
         if (clippedMarkerEdges.mAssignedLeft &&
             clippedMarkerEdges.mLeft - mContentArea.X() > 0) {
           mLeft.mWidth = clippedMarkerEdges.mLeft - mContentArea.X();
           NS_ASSERTION(mLeft.mWidth < mLeft.mIntrinsicWidth,
                        "clipping a marker should make it strictly smaller");
           clippedLeftMarker = true;
         } else {
           mLeft.mActive = guessLeft = false;
         }
         continue;
       }
       if (mRight.IsNeeded() && mRight.mActive && !clippedRightMarker) {
         if (clippedMarkerEdges.mAssignedRight &&
             mContentArea.XMost() - clippedMarkerEdges.mRight > 0) {
           mRight.mWidth = mContentArea.XMost() - clippedMarkerEdges.mRight;
           NS_ASSERTION(mRight.mWidth < mRight.mIntrinsicWidth,
                        "clipping a marker should make it strictly smaller");
           clippedRightMarker = true;
         } else {
           mRight.mActive = guessRight = false;
         }
         continue;
       }
       // The line simply has no visible content even without markers,
       // so examine the line again without suppressing markers.
       retryEmptyLine = false;
       mLeft.mWidth = mLeft.mIntrinsicWidth;
       mLeft.mActive = guessLeft = leftOverflow;
       mRight.mWidth = mRight.mIntrinsicWidth;
       mRight.mActive = guessRight = rightOverflow;
       continue;
     }
     if (guessLeft == (mLeft.mActive && mLeft.IsNeeded()) &&
         guessRight == (mRight.mActive && mRight.IsNeeded())) {
       break;
     } else {
       guessLeft = mLeft.mActive && mLeft.IsNeeded();
       guessRight = mRight.mActive && mRight.IsNeeded();
       mLeft.Reset();
       mRight.Reset();
       aFramesToHide->Clear();
     }
     NS_ASSERTION(pass == 0, "2nd pass should never guess wrong");
   } while (++pass != 2);
   if (!leftOverflow || !mLeft.mActive) {
     mLeft.Reset();
   }
   if (!rightOverflow || !mRight.mActive) {
     mRight.Reset();
   }
 }
 void
 TextOverflow::ProcessLine(const nsDisplayListSet& aLists,
                           nsLineBox*              aLine)
 {
   NS_ASSERTION(mLeft.mStyle->mType != NS_STYLE_TEXT_OVERFLOW_CLIP ||
                mRight.mStyle->mType != NS_STYLE_TEXT_OVERFLOW_CLIP,
                "TextOverflow with 'clip' for both sides");
   mLeft.Reset();
   mLeft.mActive = mLeft.mStyle->mType != NS_STYLE_TEXT_OVERFLOW_CLIP;
   mRight.Reset();
   mRight.mActive = mRight.mStyle->mType != NS_STYLE_TEXT_OVERFLOW_CLIP;
   FrameHashtable framesToHide(100);
   AlignmentEdges alignmentEdges;
   ExamineLineFrames(aLine, &framesToHide, &alignmentEdges);
   bool needLeft = mLeft.IsNeeded();
   bool needRight = mRight.IsNeeded();
   if (!needLeft && !needRight) {
     return;
   }
   NS_ASSERTION(mLeft.mStyle->mType != NS_STYLE_TEXT_OVERFLOW_CLIP ||
                !needLeft, "left marker for 'clip'");
   NS_ASSERTION(mRight.mStyle->mType != NS_STYLE_TEXT_OVERFLOW_CLIP ||
                !needRight, "right marker for 'clip'");
   // If there is insufficient space for both markers then keep the one on the
   // end side per the block's 'direction'.
   if (needLeft && needRight &&
       mLeft.mWidth + mRight.mWidth > mContentArea.width) {
     if (mBlockIsRTL) {
       needRight = false;
     } else {
       needLeft = false;
     }
   }
   nsRect insideMarkersArea = mContentArea;
   if (needLeft) {
     InflateLeft(&insideMarkersArea, -mLeft.mWidth);
   }
   if (needRight) {
     InflateRight(&insideMarkersArea, -mRight.mWidth);
   }
   if (!mCanHaveHorizontalScrollbar && alignmentEdges.mAssigned) {
     nsRect alignmentRect = nsRect(alignmentEdges.x, insideMarkersArea.y,
                                   alignmentEdges.Width(), 1);
     insideMarkersArea.IntersectRect(insideMarkersArea, alignmentRect);
   }
   // Clip and remove display items as needed at the final marker edges.
   nsDisplayList* lists[] = { aLists.Content(), aLists.PositionedDescendants() };
   for (uint32_t i = 0; i < ArrayLength(lists); ++i) {
     PruneDisplayListContents(lists[i], framesToHide, insideMarkersArea);
   }
   CreateMarkers(aLine, needLeft, needRight, insideMarkersArea);
 }
 void
 TextOverflow::PruneDisplayListContents(nsDisplayList*        aList,
                                        const FrameHashtable& aFramesToHide,
                                        const nsRect&         aInsideMarkersArea)
 {
   nsDisplayList saved;
   nsDisplayItem* item;
   while ((item = aList->RemoveBottom())) {
     nsIFrame* itemFrame = item->Frame();
     if (IsFrameDescendantOfAny(itemFrame, aFramesToHide, mBlock)) {
       item->~nsDisplayItem();
       continue;
     }
     nsDisplayList* wrapper = item->GetSameCoordinateSystemChildren();
     if (wrapper) {
       if (!itemFrame || GetSelfOrNearestBlock(itemFrame) == mBlock) {
         PruneDisplayListContents(wrapper, aFramesToHide, aInsideMarkersArea);
       }
     }
     nsCharClipDisplayItem* charClip = itemFrame ?
       nsCharClipDisplayItem::CheckCast(item) : nullptr;
     if (charClip && GetSelfOrNearestBlock(itemFrame) == mBlock) {
       nsRect rect = itemFrame->GetScrollableOverflowRect() +
                     itemFrame->GetOffsetTo(mBlock);
       if (mLeft.IsNeeded() && rect.x < aInsideMarkersArea.x) {
         nscoord left = aInsideMarkersArea.x - rect.x;
         if (MOZ_UNLIKELY(left < 0)) {
           item->~nsDisplayItem();
           continue;
         }
         charClip->mLeftEdge = left;
       }
       if (mRight.IsNeeded() && rect.XMost() > aInsideMarkersArea.XMost()) {
         nscoord right = rect.XMost() - aInsideMarkersArea.XMost();
         if (MOZ_UNLIKELY(right < 0)) {
           item->~nsDisplayItem();
           continue;
         }
         charClip->mRightEdge = right;
       }
     }
     saved.AppendToTop(item);
   }
   aList->AppendToTop(&saved);
 }
 /* static */ bool
 TextOverflow::CanHaveTextOverflow(nsDisplayListBuilder* aBuilder,
                                   nsIFrame*             aBlockFrame)
 {
   const nsStyleTextReset* style = aBlockFrame->StyleTextReset();
   // Nothing to do for text-overflow:clip or if 'overflow-x:visible'
   // or if we're just building items for event processing.
   if ((style->mTextOverflow.mLeft.mType == NS_STYLE_TEXT_OVERFLOW_CLIP &&
        style->mTextOverflow.mRight.mType == NS_STYLE_TEXT_OVERFLOW_CLIP) ||
       IsHorizontalOverflowVisible(aBlockFrame) ||
       aBuilder->IsForEventDelivery()) {
     return false;
   }
   // Skip ComboboxControlFrame because it would clip the drop-down arrow.
   // Its anon block inherits 'text-overflow' and does what is expected.
   if (aBlockFrame->GetType() == nsGkAtoms::comboboxControlFrame) {
     return false;
   }
   // Inhibit the markers if a descendant content owns the caret.
   nsRefPtr<nsCaret> caret = aBlockFrame->PresContext()->PresShell()->GetCaret();
   bool visible = false;
   if (caret && NS_SUCCEEDED(caret->GetCaretVisible(&visible)) && visible) {
     nsCOMPtr<nsISelection> domSelection = caret->GetCaretDOMSelection();
     if (domSelection) {
       nsCOMPtr<nsIDOMNode> node;
       domSelection->GetFocusNode(getter_AddRefs(node));
       nsCOMPtr<nsIContent> content = do_QueryInterface(node);
       if (content && nsContentUtils::ContentIsDescendantOf(content,
                        aBlockFrame->GetContent())) {
         return false;
       }
     }
   }
   return true;
 }
 void
 TextOverflow::CreateMarkers(const nsLineBox* aLine,
                             bool             aCreateLeft,
                             bool             aCreateRight,
                             const nsRect&    aInsideMarkersArea)
 {
   if (aCreateLeft) {
     DisplayListClipState::AutoSaveRestore clipState(mBuilder);
     nsRect markerRect = nsRect(aInsideMarkersArea.x - mLeft.mIntrinsicWidth,
                                aLine->BStart(),
                                mLeft.mIntrinsicWidth, aLine->BSize());
     markerRect += mBuilder->ToReferenceFrame(mBlock);
     ClipMarker(mContentArea + mBuilder->ToReferenceFrame(mBlock),
                markerRect, clipState);
     nsDisplayItem* marker = new (mBuilder)
       nsDisplayTextOverflowMarker(mBuilder, mBlock, markerRect,
                                   aLine->GetAscent(), mLeft.mStyle, 0);
     mMarkerList.AppendNewToTop(marker);
   }
   if (aCreateRight) {
     DisplayListClipState::AutoSaveRestore clipState(mBuilder);
     nsRect markerRect = nsRect(aInsideMarkersArea.XMost(),
                                aLine->BStart(),
                                mRight.mIntrinsicWidth, aLine->BSize());
     markerRect += mBuilder->ToReferenceFrame(mBlock);
     ClipMarker(mContentArea + mBuilder->ToReferenceFrame(mBlock),
                markerRect, clipState);
     nsDisplayItem* marker = new (mBuilder)
       nsDisplayTextOverflowMarker(mBuilder, mBlock, markerRect,
                                   aLine->GetAscent(), mRight.mStyle, 1);
     mMarkerList.AppendNewToTop(marker);
   }
 }
 void
 TextOverflow::Marker::SetupString(nsIFrame* aFrame)
 {
   if (mInitialized) {
     return;
   }
   if (mStyle->mType == NS_STYLE_TEXT_OVERFLOW_ELLIPSIS) {
     gfxTextRun* textRun = GetEllipsisTextRun(aFrame);
     if (textRun) {
       mWidth = textRun->GetAdvanceWidth(0, textRun->GetLength(), nullptr);
     } else {
       mWidth = 0;
     }
   } else {
     nsRefPtr<nsRenderingContext> rc =
       aFrame->PresContext()->PresShell()->CreateReferenceRenderingContext();
     nsRefPtr<nsFontMetrics> fm;
     nsLayoutUtils::GetFontMetricsForFrame(aFrame, getter_AddRefs(fm),
       nsLayoutUtils::FontSizeInflationFor(aFrame));
     rc->SetFont(fm);
     mWidth = nsLayoutUtils::GetStringWidth(aFrame, rc, mStyle->mString.get(),
                                            mStyle->mString.Length());
   }
   mIntrinsicWidth = mWidth;
   mInitialized = true;
 }
 }  // namespace css
 }  // namespace mozilla

The Tor Browser / annotate

layout/generic/TextOverflow.cpp@b8a032363ba2 (annotated)

layout/generic/TextOverflow.cpp