[css-grid] Refactor GridSpan to avoid pointers

third_party/WebKit/Source/core/style/GridResolvedPosition.cpp

 // Copyright 2014 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "config.h"
 #include "core/style/GridResolvedPosition.h"
 
 #include "core/layout/LayoutBox.h"
 #include "core/style/GridCoordinate.h"
 
@@ skipping 57 matching lines @@
     initialAndFinalPositionsFromStyle(gridContainerStyle, gridItem, direction, initialPosition, finalPosition);
 
     GridPositionSide finalSide = finalPositionSide(direction);
 
     // This method will only be used when both positions need to be resolved against the opposite one.
     ASSERT(initialPosition.shouldBeResolvedAgainstOppositePosition() && finalPosition.shouldBeResolvedAgainstOppositePosition());
 
     GridResolvedPosition resolvedFinalPosition = resolvedInitialPosition.next();
 
     if (initialPosition.isSpan())
-        return *resolveGridPositionAgainstOppositePosition(gridContainerStyle, resolvedInitialPosition, initialPosition, finalSide);
+        return resolveGridPositionAgainstOppositePosition(gridContainerStyle, resolvedInitialPosition, initialPosition, finalSide);
     if (finalPosition.isSpan())
-        return *resolveGridPositionAgainstOppositePosition(gridContainerStyle, resolvedInitialPosition, finalPosition, finalSide);
+        return resolveGridPositionAgainstOppositePosition(gridContainerStyle, resolvedInitialPosition, finalPosition, finalSide);
 
-    return GridSpan(resolvedInitialPosition, resolvedFinalPosition);
+    return GridSpan::definiteGridSpan(resolvedInitialPosition, resolvedFinalPosition);
 }
 
-PassOwnPtr<GridSpan> GridResolvedPosition::resolveGridPositionsFromStyle(const ComputedStyle& gridContainerStyle, const LayoutBox& gridItem, GridTrackSizingDirection direction)
+GridSpan GridResolvedPosition::resolveGridPositionsFromStyle(const ComputedStyle& gridContainerStyle, const LayoutBox& gridItem, GridTrackSizingDirection direction)
 {
     GridPosition initialPosition, finalPosition;
     initialAndFinalPositionsFromStyle(gridContainerStyle, gridItem, direction, initialPosition, finalPosition);
 
     GridPositionSide initialSide = initialPositionSide(direction);
     GridPositionSide finalSide = finalPositionSide(direction);
 
     if (initialPosition.shouldBeResolvedAgainstOppositePosition() && finalPosition.shouldBeResolvedAgainstOppositePosition()) {
         // We can't get our grid positions without running the auto placement algorithm.
-        return nullptr;
+        return GridSpan::indefiniteGridSpan();
     }
 
     if (initialPosition.shouldBeResolvedAgainstOppositePosition()) {
         // Infer the position from the final position ('auto / 1' or 'span 2 / 3' case).
         GridResolvedPosition finalResolvedPosition = resolveGridPositionFromStyle(gridContainerStyle, finalPosition, finalSide);
         return resolveGridPositionAgainstOppositePosition(gridContainerStyle, finalResolvedPosition, initialPosition, initialSide);
     }
 
     if (finalPosition.shouldBeResolvedAgainstOppositePosition()) {
         // Infer our position from the initial position ('1 / auto' or '3 / span 2' case).
         GridResolvedPosition initialResolvedPosition = resolveGridPositionFromStyle(gridContainerStyle, initialPosition, initialSide);
         return resolveGridPositionAgainstOppositePosition(gridContainerStyle, initialResolvedPosition, finalPosition, finalSide);
     }
 
     GridResolvedPosition resolvedInitialPosition = resolveGridPositionFromStyle(gridContainerStyle, initialPosition, initialSide);
     GridResolvedPosition resolvedFinalPosition = resolveGridPositionFromStyle(gridContainerStyle, finalPosition, finalSide);
 
     // If 'grid-after' specifies a line at or before that specified by 'grid-before', it computes to 'span 1'.
     if (resolvedFinalPosition <= resolvedInitialPosition)
         resolvedFinalPosition = resolvedInitialPosition.next();
 
-    return adoptPtr(new GridSpan(resolvedInitialPosition, resolvedFinalPosition));
+    return GridSpan::definiteGridSpan(resolvedInitialPosition, resolvedFinalPosition);
 }
 
 size_t GridResolvedPosition::explicitGridColumnCount(const ComputedStyle& gridContainerStyle)
 {
     return std::min(gridContainerStyle.gridTemplateColumns().size(), kGridMaxTracks);
 }
 
 size_t GridResolvedPosition::explicitGridRowCount(const ComputedStyle& gridContainerStyle)
 {
     return std::min(gridContainerStyle.gridTemplateRows().size(), kGridMaxTracks);
@@ skipping 75 matching lines @@
     case AutoPosition:
     case SpanPosition:
         // 'auto' and span depend on the opposite position for resolution (e.g. grid-row: auto / 1 or grid-column: span 3 / "myHeader").
         ASSERT_NOT_REACHED();
         return GridResolvedPosition(0);
     }
     ASSERT_NOT_REACHED();
     return GridResolvedPosition(0);
 }
 
-PassOwnPtr<GridSpan> GridResolvedPosition::resolveGridPositionAgainstOppositePosition(const ComputedStyle& gridContainerStyle, const GridResolvedPosition& resolvedOppositePosition, const GridPosition& position, GridPositionSide side)
+GridSpan GridResolvedPosition::resolveGridPositionAgainstOppositePosition(const ComputedStyle& gridContainerStyle, const GridResolvedPosition& resolvedOppositePosition, const GridPosition& position, GridPositionSide side)
 {
     if (position.isAuto()) {
         if ((side == ColumnStartSide || side == RowStartSide) && resolvedOppositePosition.toInt())
-            return GridSpan::create(resolvedOppositePosition.prev(), resolvedOppositePosition);
-        return GridSpan::create(resolvedOppositePosition, resolvedOppositePosition.next());
+            return GridSpan::definiteGridSpan(resolvedOppositePosition.prev(), resolvedOppositePosition);
+        return GridSpan::definiteGridSpan(resolvedOppositePosition, resolvedOppositePosition.next());
     }
 
     ASSERT(position.isSpan());
     ASSERT(position.spanPosition() > 0);
 
     if (!position.namedGridLine().isNull()) {
         // span 2 'c' -> we need to find the appropriate grid line before / after our opposite position.
         return resolveNamedGridLinePositionAgainstOppositePosition(gridContainerStyle, resolvedOppositePosition, position, side);
     }
 
-    return GridSpan::createWithSpanAgainstOpposite(resolvedOppositePosition, position, side);
+    return GridSpan::definiteGridSpanWithSpanAgainstOpposite(resolvedOppositePosition, position, side);
 }
 
-PassOwnPtr<GridSpan> GridResolvedPosition::resolveNamedGridLinePositionAgainstOppositePosition(const ComputedStyle& gridContainerStyle, const GridResolvedPosition& resolvedOppositePosition, const GridPosition& position, GridPositionSide side)
+GridSpan GridResolvedPosition::resolveNamedGridLinePositionAgainstOppositePosition(const ComputedStyle& gridContainerStyle, const GridResolvedPosition& resolvedOppositePosition, const GridPosition& position, GridPositionSide side)
 {
     ASSERT(position.isSpan());
     ASSERT(!position.namedGridLine().isNull());
     // Negative positions are not allowed per the specification and should have been handled during parsing.
     ASSERT(position.spanPosition() > 0);
 
     const NamedGridLinesMap& gridLinesNames = gridLinesForSide(gridContainerStyle, side);
     NamedGridLinesMap::const_iterator it = gridLinesNames.find(position.namedGridLine());
 
     // If there is no named grid line of that name, we resolve the position to 'auto' (which is equivalent to 'span 1' in this case).
     // See http://lists.w3.org/Archives/Public/www-style/2013Jun/0394.html.
     if (it == gridLinesNames.end()) {
         if ((side == ColumnStartSide || side == RowStartSide) && resolvedOppositePosition.toInt())
-            return GridSpan::create(resolvedOppositePosition.prev(), resolvedOppositePosition);
-        return GridSpan::create(resolvedOppositePosition, resolvedOppositePosition.next());
+            return GridSpan::definiteGridSpan(resolvedOppositePosition.prev(), resolvedOppositePosition);
+        return GridSpan::definiteGridSpan(resolvedOppositePosition, resolvedOppositePosition.next());
     }
 
-    return GridSpan::createWithNamedSpanAgainstOpposite(resolvedOppositePosition, position, side, it->value);
+    return GridSpan::definiteGridSpanWithNamedSpanAgainstOpposite(resolvedOppositePosition, position, side, it->value);
 }
 
 } // namespace blink