Bug 1240795 - [css-grid] Refactor GetComputedTemplateColumns/Rows to return a self-contained value. r=dholbert

layout/generic/nsGridContainerFrame.cpp

@@ -3341,14 +3341,21 @@ nsGridContainerFrame::Reflow(nsPresContext*           aPresContext,
   for (const TrackSize& sz : gridReflowState.mCols.mSizes) {
     colTrackSizes.AppendElement(sz.mBase);
   }
-  Properties().Set(GridColTrackSizes(),
-                   new nsTArray<nscoord>(mozilla::Move(colTrackSizes)));
+  ComputedGridTrackInfo* colInfo = new ComputedGridTrackInfo(
+    gridReflowState.mColFunctions.mExplicitGridOffset,
+    gridReflowState.mColFunctions.NumExplicitTracks(),
+    Move(colTrackSizes));
+  Properties().Set(GridColTrackInfo(), colInfo);
+
   nsTArray<nscoord> rowTrackSizes(gridReflowState.mRows.mSizes.Length());
   for (const TrackSize& sz : gridReflowState.mRows.mSizes) {
     rowTrackSizes.AppendElement(sz.mBase);
   }
-  Properties().Set(GridRowTrackSizes(),
-                   new nsTArray<nscoord>(mozilla::Move(rowTrackSizes)));
+  ComputedGridTrackInfo* rowInfo = new ComputedGridTrackInfo(
+    gridReflowState.mRowFunctions.mExplicitGridOffset,
+    gridReflowState.mRowFunctions.NumExplicitTracks(),
+    Move(rowTrackSizes));
+  Properties().Set(GridRowTrackInfo(), rowInfo);
   
   nscoord bSize = 0;
   if (computedBSize == NS_AUTOHEIGHT) {

layout/generic/nsGridContainerFrame.h

@@ -21,6 +21,25 @@
 nsContainerFrame* NS_NewGridContainerFrame(nsIPresShell* aPresShell,
                                            nsStyleContext* aContext);
 
+namespace mozilla {
+/**
+ * The number of implicit / explicit tracks and their sizes.
+ */
+struct ComputedGridTrackInfo
+{
+  ComputedGridTrackInfo(uint32_t aNumLeadingImplicitTracks,
+                        uint32_t aNumExplicitTracks,
+                        nsTArray<nscoord>&& aSizes)
+    : mNumLeadingImplicitTracks(aNumLeadingImplicitTracks)
+    , mNumExplicitTracks(aNumExplicitTracks)
+    , mSizes(aSizes)
+  {}
+  uint32_t mNumLeadingImplicitTracks;
+  uint32_t mNumExplicitTracks;
+  nsTArray<nscoord> mSizes;
+};
+} // namespace mozilla
+
 class nsGridContainerFrame final : public nsContainerFrame
 {
 public:
@@ -88,32 +107,18 @@ public:
 
   NS_DECLARE_FRAME_PROPERTY(GridItemContainingBlockRect, DeleteValue<nsRect>)
 
-  NS_DECLARE_FRAME_PROPERTY(GridColTrackSizes, DeleteValue<nsTArray<nscoord>>)
-
-  const nsTArray<nscoord>* GetComputedTemplateColumns()
+  NS_DECLARE_FRAME_PROPERTY(GridColTrackInfo, DeleteValue<ComputedGridTrackInfo>)
+  const ComputedGridTrackInfo* GetComputedTemplateColumns()
   {
-    return static_cast<nsTArray<nscoord>*>(Properties().Get(GridColTrackSizes()));
+    return static_cast<ComputedGridTrackInfo*>(Properties().Get(GridColTrackInfo()));
   }
 
-  NS_DECLARE_FRAME_PROPERTY(GridRowTrackSizes, DeleteValue<nsTArray<nscoord>>)
-
-  const nsTArray<nscoord>* GetComputedTemplateRows()
+  NS_DECLARE_FRAME_PROPERTY(GridRowTrackInfo, DeleteValue<ComputedGridTrackInfo>)
+  const ComputedGridTrackInfo* GetComputedTemplateRows()
   {
-    return static_cast<nsTArray<nscoord>*>(Properties().Get(GridRowTrackSizes()));
+    return static_cast<ComputedGridTrackInfo*>(Properties().Get(GridRowTrackInfo()));
   }
 
-  /**
-   * Return the number of implicit tracks that comes before the explicit grid.
-   */
-  uint32_t NumImplicitLeadingCols() const { return mExplicitGridOffsetCol; }
-  uint32_t NumImplicitLeadingRows() const { return mExplicitGridOffsetRow; }
-
-  /**
-   * Return the number of explicit tracks.
-   */
-  uint32_t NumExplicitCols() const { return mExplicitGridColEnd - 1; }
-  uint32_t NumExplicitRows() const { return mExplicitGridRowEnd - 1; }
-
 protected:
   static const uint32_t kAutoLine;
   // The maximum line number, in the zero-based translated grid.

layout/style/nsComputedDOMStyle.cpp

@@ -2449,10 +2449,9 @@ nsComputedDOMStyle::GetGridTrackSize(const nsStyleCoord& aMinValue,
 }
 
 already_AddRefed<CSSValue>
-nsComputedDOMStyle::GetGridTemplateColumnsRows(const nsStyleGridTemplate& aTrackList,
-                                               const uint32_t aNumLeadingImplicitTracks,
-                                               const uint32_t aNumExplicitTracks,
-                                               const nsTArray<nscoord>* aTrackSizes)
+nsComputedDOMStyle::GetGridTemplateColumnsRows(
+  const nsStyleGridTemplate&   aTrackList,
+  const ComputedGridTrackInfo* aTrackInfo)
 {
   if (aTrackList.mIsSubgrid) {
     // XXX TODO: add support for repeat(auto-fill) for 'subgrid' (bug 1234311)
@@ -2491,17 +2490,18 @@ nsComputedDOMStyle::GetGridTemplateColumnsRows(const nsStyleGridTemplate& aTrack
   uint32_t numSizes = aTrackList.mMinTrackSizingFunctions.Length();
   MOZ_ASSERT(aTrackList.mMaxTrackSizingFunctions.Length() == numSizes,
              "Different number of min and max track sizing functions");
-  if (aTrackSizes) {
+  if (aTrackInfo) {
     DebugOnly<bool> isAutoFill =
       aTrackList.HasRepeatAuto() && aTrackList.mIsAutoFill;
     DebugOnly<bool> isAutoFit =
       aTrackList.HasRepeatAuto() && !aTrackList.mIsAutoFill;
-    MOZ_ASSERT(aNumExplicitTracks == numSizes ||
-               (isAutoFill && aNumExplicitTracks >= numSizes) ||
-               (isAutoFit && aNumExplicitTracks + 1 >= numSizes),
+    DebugOnly<uint32_t> numExplicitTracks = aTrackInfo->mNumExplicitTracks;
+    MOZ_ASSERT(numExplicitTracks == numSizes ||
+               (isAutoFill && numExplicitTracks >= numSizes) ||
+               (isAutoFit && numExplicitTracks + 1 >= numSizes),
                "expected all explicit tracks (or possibly one less, if there's "
                "an 'auto-fit' track, since that can collapse away)");
-    numSizes = aTrackSizes->Length();
+    numSizes = aTrackInfo->mSizes.Length();
   }
 
   // An empty <track-list> is represented as "none" in syntax.
@@ -2512,29 +2512,32 @@ nsComputedDOMStyle::GetGridTemplateColumnsRows(const nsStyleGridTemplate& aTrack
   }
 
   RefPtr<nsDOMCSSValueList> valueList = GetROCSSValueList(false);
-  if (aTrackSizes) {
+  if (aTrackInfo) {
     // We've done layout on the grid and have resolved the sizes of its tracks,
     // so we'll return those sizes here.  The grid spec says we MAY use
     // repeat(<positive-integer>, Npx) here for consecutive tracks with the same
     // size, but that doesn't seem worth doing since even for repeat(auto-*)
     // the resolved size might differ for the repeated tracks.
+    const nsTArray<nscoord>& trackSizes = aTrackInfo->mSizes;
+    const uint32_t numExplicitTracks = aTrackInfo->mNumExplicitTracks;
+    const uint32_t numLeadingImplicitTracks = aTrackInfo->mNumLeadingImplicitTracks;
     MOZ_ASSERT(numSizes > 0 &&
-               numSizes >= aNumLeadingImplicitTracks + aNumExplicitTracks);
+               numSizes >= numLeadingImplicitTracks + numExplicitTracks);
 
     // Add any leading implicit tracks.
-    for (uint32_t i = 0; i < aNumLeadingImplicitTracks; ++i) {
+    for (uint32_t i = 0; i < numLeadingImplicitTracks; ++i) {
       RefPtr<nsROCSSPrimitiveValue> val = new nsROCSSPrimitiveValue;
-      val->SetAppUnits((*aTrackSizes)[i]);
+      val->SetAppUnits(trackSizes[i]);
       valueList->AppendCSSValue(val.forget());
     }
 
     // Then add any explicit tracks.
-    if (aNumExplicitTracks) {
+    if (numExplicitTracks) {
       int32_t endOfRepeat = 0;  // first index after any repeat() tracks
       int32_t offsetToLastRepeat = 0;
       if (aTrackList.HasRepeatAuto()) {
         // offsetToLastRepeat is -1 if all repeat(auto-fit) tracks are empty
-        offsetToLastRepeat = aNumExplicitTracks + 1 - aTrackList.mLineNameLists.Length();
+        offsetToLastRepeat = numExplicitTracks + 1 - aTrackList.mLineNameLists.Length();
         endOfRepeat = aTrackList.mRepeatAutoIndex + offsetToLastRepeat + 1;
       }
       for (int32_t i = 0;; i++) {
@@ -2569,20 +2572,20 @@ nsComputedDOMStyle::GetGridTemplateColumnsRows(const nsStyleGridTemplate& aTrack
           const nsTArray<nsString>& lineNames = aTrackList.mLineNameLists[i];
           AppendGridLineNames(valueList, lineNames);
         }
-        if (uint32_t(i) == aNumExplicitTracks) {
+        if (uint32_t(i) == numExplicitTracks) {
           break;
         }
         RefPtr<nsROCSSPrimitiveValue> val = new nsROCSSPrimitiveValue;
-        val->SetAppUnits((*aTrackSizes)[i + aNumLeadingImplicitTracks]);
+        val->SetAppUnits(trackSizes[i + numLeadingImplicitTracks]);
         valueList->AppendCSSValue(val.forget());
       }
     }
 
     // Add any trailing implicit tracks.
-    for (uint32_t i = aNumLeadingImplicitTracks + aNumExplicitTracks;
+    for (uint32_t i = numLeadingImplicitTracks + numExplicitTracks;
          i < numSizes; ++i) {
       RefPtr<nsROCSSPrimitiveValue> val = new nsROCSSPrimitiveValue;
-      val->SetAppUnits((*aTrackSizes)[i]);
+      val->SetAppUnits(trackSizes[i]);
       valueList->AppendCSSValue(val.forget());
     }
   } else {
@@ -2656,45 +2659,31 @@ nsComputedDOMStyle::DoGetGridAutoRows()
 already_AddRefed<CSSValue>
 nsComputedDOMStyle::DoGetGridTemplateColumns()
 {
-  const nsTArray<nscoord>* trackSizes = nullptr;
-  uint32_t numLeadingImplicitTracks = 0;
-  uint32_t numExplicitTracks = 0;
+  const ComputedGridTrackInfo* info = nullptr;
   if (mInnerFrame) {
     nsIFrame* gridContainerCandidate = mInnerFrame->GetContentInsertionFrame();
     if (gridContainerCandidate &&
         gridContainerCandidate->GetType() == nsGkAtoms::gridContainerFrame) {
-      auto gridContainer = static_cast<nsGridContainerFrame*>(gridContainerCandidate);
-      trackSizes = gridContainer->GetComputedTemplateColumns();
-      numLeadingImplicitTracks = gridContainer->NumImplicitLeadingCols();
-      numExplicitTracks = gridContainer->NumExplicitCols();
+      info = static_cast<nsGridContainerFrame*>(gridContainerCandidate)->
+        GetComputedTemplateColumns();
     }
   }
-  return GetGridTemplateColumnsRows(StylePosition()->mGridTemplateColumns,
-                                    numLeadingImplicitTracks,
-                                    numExplicitTracks,
-                                    trackSizes);
+  return GetGridTemplateColumnsRows(StylePosition()->mGridTemplateColumns, info);
 }
 
 already_AddRefed<CSSValue>
 nsComputedDOMStyle::DoGetGridTemplateRows()
 {
-  const nsTArray<nscoord>* trackSizes = nullptr;
-  uint32_t numLeadingImplicitTracks = 0;
-  uint32_t numExplicitTracks = 0;
+  const ComputedGridTrackInfo* info = nullptr;
   if (mInnerFrame) {
     nsIFrame* gridContainerCandidate = mInnerFrame->GetContentInsertionFrame();
     if (gridContainerCandidate &&
         gridContainerCandidate->GetType() == nsGkAtoms::gridContainerFrame) {
-      auto gridContainer = static_cast<nsGridContainerFrame*>(gridContainerCandidate);
-      trackSizes = gridContainer->GetComputedTemplateRows();
-      numLeadingImplicitTracks = gridContainer->NumImplicitLeadingRows();
-      numExplicitTracks = gridContainer->NumExplicitRows();
+      info = static_cast<nsGridContainerFrame*>(gridContainerCandidate)->
+        GetComputedTemplateRows();
      }
   }
-  return GetGridTemplateColumnsRows(StylePosition()->mGridTemplateRows,
-                                    numLeadingImplicitTracks,
-                                    numExplicitTracks,
-                                    trackSizes);
+  return GetGridTemplateColumnsRows(StylePosition()->mGridTemplateRows, info);
 }
 
 already_AddRefed<CSSValue>

layout/style/nsComputedDOMStyle.h

@@ -27,6 +27,7 @@ namespace mozilla {
 namespace dom {
 class Element;
 } // namespace dom
+struct ComputedGridTrackInfo;
 } // namespace mozilla
 
 struct nsComputedStyleMap;
@@ -192,9 +193,7 @@ private:
                                               const nsStyleCoord& aMaxSize);
   already_AddRefed<CSSValue> GetGridTemplateColumnsRows(
     const nsStyleGridTemplate& aTrackList,
-    const uint32_t aNumLeadingImplicitTracks,
-    const uint32_t aNumExplicitTracks,
-    const nsTArray<nscoord>* aTrackSizes);
+    const mozilla::ComputedGridTrackInfo* aTrackInfo);
   already_AddRefed<CSSValue> GetGridLine(const nsStyleGridLine& aGridLine);
 
   bool GetLineHeightCoord(nscoord& aCoord);