1 files changed, 278 insertions, 0 deletions
diff --git a/layout/generic/nsPlaceholderFrame.cpp b/layout/generic/nsPlaceholderFrame.cpp
new file mode 100644
index 000000000..2b6799f48
--- /dev/null
+++ b/layout/generic/nsPlaceholderFrame.cpp
@@ -0,0 +1,278 @@
+/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* 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 the point that anchors out-of-flow rendering
+ * objects such as floats and absolutely positioned elements
+ */
+
+#include "nsPlaceholderFrame.h"
+
+#include "gfxUtils.h"
+#include "mozilla/gfx/2D.h"
+#include "nsDisplayList.h"
+#include "nsFrameManager.h"
+#include "nsLayoutUtils.h"
+#include "nsPresContext.h"
+#include "nsRenderingContext.h"
+#include "nsIFrameInlines.h"
+#include "nsIContentInlines.h"
+
+using namespace mozilla;
+using namespace mozilla::gfx;
+
+nsIFrame*
+NS_NewPlaceholderFrame(nsIPresShell* aPresShell, nsStyleContext* aContext,
+                       nsFrameState aTypeBit)
+{
+  return new (aPresShell) nsPlaceholderFrame(aContext, aTypeBit);
+}
+
+NS_IMPL_FRAMEARENA_HELPERS(nsPlaceholderFrame)
+
+#ifdef DEBUG
+NS_QUERYFRAME_HEAD(nsPlaceholderFrame)
+  NS_QUERYFRAME_ENTRY(nsPlaceholderFrame)
+NS_QUERYFRAME_TAIL_INHERITING(nsFrame)
+#endif
+
+/* virtual */ nsSize
+nsPlaceholderFrame::GetXULMinSize(nsBoxLayoutState& aBoxLayoutState)
+{
+  nsSize size(0, 0);
+  DISPLAY_MIN_SIZE(this, size);
+  return size;
+}
+
+/* virtual */ nsSize
+nsPlaceholderFrame::GetXULPrefSize(nsBoxLayoutState& aBoxLayoutState)
+{
+  nsSize size(0, 0);
+  DISPLAY_PREF_SIZE(this, size);
+  return size;
+}
+
+/* virtual */ nsSize
+nsPlaceholderFrame::GetXULMaxSize(nsBoxLayoutState& aBoxLayoutState)
+{
+  nsSize size(NS_INTRINSICSIZE, NS_INTRINSICSIZE);
+  DISPLAY_MAX_SIZE(this, size);
+  return size;
+}
+
+/* virtual */ void
+nsPlaceholderFrame::AddInlineMinISize(nsRenderingContext* aRenderingContext,
+                                      nsIFrame::InlineMinISizeData* aData)
+{
+  // Override AddInlineMinWith so that *nothing* happens.  In
+  // particular, we don't want to zero out |aData->mTrailingWhitespace|,
+  // since nsLineLayout skips placeholders when trimming trailing
+  // whitespace, and we don't want to set aData->mSkipWhitespace to
+  // false.
+
+  // ...but push floats onto the list
+  if (mOutOfFlowFrame->IsFloating()) {
+    nscoord floatWidth =
+      nsLayoutUtils::IntrinsicForContainer(aRenderingContext,
+                                           mOutOfFlowFrame,
+                                           nsLayoutUtils::MIN_ISIZE);
+    aData->mFloats.AppendElement(
+      InlineIntrinsicISizeData::FloatInfo(mOutOfFlowFrame, floatWidth));
+  }
+}
+
+/* virtual */ void
+nsPlaceholderFrame::AddInlinePrefISize(nsRenderingContext* aRenderingContext,
+                                       nsIFrame::InlinePrefISizeData* aData)
+{
+  // Override AddInlinePrefWith so that *nothing* happens.  In
+  // particular, we don't want to zero out |aData->mTrailingWhitespace|,
+  // since nsLineLayout skips placeholders when trimming trailing
+  // whitespace, and we don't want to set aData->mSkipWhitespace to
+  // false.
+
+  // ...but push floats onto the list
+  if (mOutOfFlowFrame->IsFloating()) {
+    nscoord floatWidth =
+      nsLayoutUtils::IntrinsicForContainer(aRenderingContext,
+                                           mOutOfFlowFrame,
+                                           nsLayoutUtils::PREF_ISIZE);
+    aData->mFloats.AppendElement(
+      InlineIntrinsicISizeData::FloatInfo(mOutOfFlowFrame, floatWidth));
+  }
+}
+
+void
+nsPlaceholderFrame::Reflow(nsPresContext*           aPresContext,
+                           ReflowOutput&     aDesiredSize,
+                           const ReflowInput& aReflowInput,
+                           nsReflowStatus&          aStatus)
+{
+#ifdef DEBUG
+  // We should be getting reflowed before our out-of-flow.
+  // If this is our first reflow, and our out-of-flow has already received its
+  // first reflow (before us), complain.
+  // XXXdholbert This "look for a previous continuation or IB-split sibling"
+  // code could use nsLayoutUtils::GetPrevContinuationOrIBSplitSibling(), if
+  // we ever add a function like that. (We currently have a "Next" version.)
+  if ((GetStateBits() & NS_FRAME_FIRST_REFLOW) &&
+      !(mOutOfFlowFrame->GetStateBits() & NS_FRAME_FIRST_REFLOW)) {
+
+    // Unfortunately, this can currently happen when the placeholder is in a
+    // later continuation or later IB-split sibling than its out-of-flow (as
+    // is the case in some of our existing unit tests). So for now, in that
+    // case, we'll warn instead of asserting.
+    bool isInContinuationOrIBSplit = false;
+    nsIFrame* ancestor = this;
+    while ((ancestor = ancestor->GetParent())) {
+      if (ancestor->GetPrevContinuation() ||
+          ancestor->Properties().Get(IBSplitPrevSibling())) {
+        isInContinuationOrIBSplit = true;
+        break;
+      }
+    }
+
+    if (isInContinuationOrIBSplit) {
+      NS_WARNING("Out-of-flow frame got reflowed before its placeholder");
+    } else {
+      NS_ERROR("Out-of-flow frame got reflowed before its placeholder");
+    }
+  }
+#endif
+
+  MarkInReflow();
+  DO_GLOBAL_REFLOW_COUNT("nsPlaceholderFrame");
+  DISPLAY_REFLOW(aPresContext, this, aReflowInput, aDesiredSize, aStatus);
+  aDesiredSize.ClearSize();
+
+  aStatus = NS_FRAME_COMPLETE;
+  NS_FRAME_SET_TRUNCATION(aStatus, aReflowInput, aDesiredSize);
+}
+
+void
+nsPlaceholderFrame::DestroyFrom(nsIFrame* aDestructRoot)
+{
+  nsIFrame* oof = mOutOfFlowFrame;
+  if (oof) {
+    // Unregister out-of-flow frame
+    nsFrameManager* fm = PresContext()->GetPresShell()->FrameManager();
+    fm->UnregisterPlaceholderFrame(this);
+    mOutOfFlowFrame = nullptr;
+    // If aDestructRoot is not an ancestor of the out-of-flow frame,
+    // then call RemoveFrame on it here.
+    // Also destroy it here if it's a popup frame. (Bug 96291)
+    if ((GetStateBits() & PLACEHOLDER_FOR_POPUP) ||
+        !nsLayoutUtils::IsProperAncestorFrame(aDestructRoot, oof)) {
+      ChildListID listId = nsLayoutUtils::GetChildListNameFor(oof);
+      fm->RemoveFrame(listId, oof);
+    }
+    // else oof will be destroyed by its parent
+  }
+
+  nsFrame::DestroyFrom(aDestructRoot);
+}
+
+nsIAtom*
+nsPlaceholderFrame::GetType() const
+{
+  return nsGkAtoms::placeholderFrame;
+}
+
+/* virtual */ bool
+nsPlaceholderFrame::CanContinueTextRun() const
+{
+  if (!mOutOfFlowFrame) {
+    return false;
+  }
+  // first-letter frames can continue text runs, and placeholders for floated
+  // first-letter frames can too
+  return mOutOfFlowFrame->CanContinueTextRun();
+}
+
+nsStyleContext*
+nsPlaceholderFrame::GetParentStyleContext(nsIFrame** aProviderFrame) const
+{
+  NS_PRECONDITION(GetParent(), "How can we not have a parent here?");
+
+  nsIContent* parentContent = mContent ? mContent->GetFlattenedTreeParent() : nullptr;
+  if (parentContent) {
+    nsStyleContext* sc =
+      PresContext()->FrameManager()->GetDisplayContentsStyleFor(parentContent);
+    if (sc) {
+      *aProviderFrame = nullptr;
+      return sc;
+    }
+  }
+
+  // Lie about our pseudo so we can step out of all anon boxes and
+  // pseudo-elements.  The other option would be to reimplement the
+  // {ib} split gunk here.
+  *aProviderFrame = CorrectStyleParentFrame(GetParent(), nsGkAtoms::placeholderFrame);
+  return *aProviderFrame ? (*aProviderFrame)->StyleContext() : nullptr;
+}
+
+
+#ifdef DEBUG
+static void
+PaintDebugPlaceholder(nsIFrame* aFrame, DrawTarget* aDrawTarget,
+                      const nsRect& aDirtyRect, nsPoint aPt)
+{
+  ColorPattern cyan(ToDeviceColor(Color(0.f, 1.f, 1.f, 1.f)));
+  int32_t appUnitsPerDevPixel = aFrame->PresContext()->AppUnitsPerDevPixel();
+
+  nscoord x = nsPresContext::CSSPixelsToAppUnits(-5);
+  nsRect r(aPt.x + x, aPt.y,
+           nsPresContext::CSSPixelsToAppUnits(13),
+           nsPresContext::CSSPixelsToAppUnits(3));
+  aDrawTarget->FillRect(NSRectToRect(r, appUnitsPerDevPixel), cyan);
+
+  nscoord y = nsPresContext::CSSPixelsToAppUnits(-10);
+  r = nsRect(aPt.x, aPt.y + y,
+             nsPresContext::CSSPixelsToAppUnits(3),
+             nsPresContext::CSSPixelsToAppUnits(10));
+  aDrawTarget->FillRect(NSRectToRect(r, appUnitsPerDevPixel), cyan);
+}
+#endif // DEBUG
+
+#if defined(DEBUG) || (defined(MOZ_REFLOW_PERF_DSP) && defined(MOZ_REFLOW_PERF))
+
+void
+nsPlaceholderFrame::BuildDisplayList(nsDisplayListBuilder*   aBuilder,
+                                     const nsRect&           aDirtyRect,
+                                     const nsDisplayListSet& aLists)
+{
+  DO_GLOBAL_REFLOW_COUNT_DSP("nsPlaceholderFrame");
+  
+#ifdef DEBUG
+  if (GetShowFrameBorders()) {
+    aLists.Outlines()->AppendNewToTop(
+      new (aBuilder) nsDisplayGeneric(aBuilder, this, PaintDebugPlaceholder,
+                                      "DebugPlaceholder",
+                                      nsDisplayItem::TYPE_DEBUG_PLACEHOLDER));
+  }
+#endif
+}
+#endif // DEBUG || (MOZ_REFLOW_PERF_DSP && MOZ_REFLOW_PERF)
+
+#ifdef DEBUG_FRAME_DUMP
+nsresult
+nsPlaceholderFrame::GetFrameName(nsAString& aResult) const
+{
+  return MakeFrameName(NS_LITERAL_STRING("Placeholder"), aResult);
+}
+
+void
+nsPlaceholderFrame::List(FILE* out, const char* aPrefix, uint32_t aFlags) const
+{
+  nsCString str;
+  ListGeneric(str, aPrefix, aFlags);
+
+  if (mOutOfFlowFrame) {
+    str += " outOfFlowFrame=";
+    nsFrame::ListTag(str, mOutOfFlowFrame);
+  }
+  fprintf_stderr(out, "%s\n", str.get());
+}
+#endif