Implementing `switch` expressions in `rendering/` (#143812)

This pull request is part of the effort to solve issue #136139.

The previous [`switch` expressions PR](https://github.com/flutter/flutter/pull/143496) was comprised of many simple changes throughout `flutter/lib/src/`, but due to some more in-depth refactoring in `flutter/lib/src/rendering/`, I decided to submit the changes to this directory as a separate pull request.

There was really just one function that I changed significantly; I'll add a comment for explanation.

packages/flutter/lib/src/rendering/decorated_sliver.dart

@@ -93,32 +93,27 @@ class RenderDecoratedSliver extends RenderProxySliver {
 
   @override
   void paint(PaintingContext context, Offset offset) {
-    if (child != null && child!.geometry!.visible) {
-      final SliverPhysicalParentData childParentData = child!.parentData! as SliverPhysicalParentData;
-      final Size childSize;
-      final Offset scrollOffset;
-
-      // In the case where the child sliver has infinite scroll extent, the decoration
-      // should only extend down to the bottom cache extent.
-      final double cappedMainAxisExtent = child!.geometry!.scrollExtent.isInfinite
-        ? constraints.scrollOffset + child!.geometry!.cacheExtent + constraints.cacheOrigin
-        : child!.geometry!.scrollExtent;
-      switch (constraints.axis) {
-        case Axis.vertical:
-          childSize = Size(constraints.crossAxisExtent, cappedMainAxisExtent);
-          scrollOffset = Offset(0.0, -constraints.scrollOffset);
-        case Axis.horizontal:
-          childSize = Size(cappedMainAxisExtent, constraints.crossAxisExtent);
-          scrollOffset = Offset(-constraints.scrollOffset, 0.0);
-      }
-      final Offset childOffset = offset + childParentData.paintOffset;
-      if (position == DecorationPosition.background) {
-        _painter!.paint(context.canvas, childOffset + scrollOffset, configuration.copyWith(size: childSize));
-      }
-      context.paintChild(child!, childOffset);
-      if (position == DecorationPosition.foreground) {
-        _painter!.paint(context.canvas, childOffset + scrollOffset, configuration.copyWith(size: childSize));
-      }
+    if (child == null || !child!.geometry!.visible) {
+      return;
+    }
+    // In the case where the child sliver has infinite scroll extent, the decoration
+    // should only extend down to the bottom cache extent.
+    final double cappedMainAxisExtent = child!.geometry!.scrollExtent.isInfinite
+      ? constraints.scrollOffset + child!.geometry!.cacheExtent + constraints.cacheOrigin
+      : child!.geometry!.scrollExtent;
+    final (Size childSize, Offset scrollOffset) = switch (constraints.axis) {
+      Axis.horizontal => (Size(cappedMainAxisExtent, constraints.crossAxisExtent), Offset(-constraints.scrollOffset, 0.0)),
+      Axis.vertical   => (Size(constraints.crossAxisExtent, cappedMainAxisExtent), Offset(0.0, -constraints.scrollOffset)),
+    };
+    offset += (child!.parentData! as SliverPhysicalParentData).paintOffset;
+    void paintDecoration() => _painter!.paint(context.canvas, offset + scrollOffset, configuration.copyWith(size: childSize));
+    switch (position) {
+      case DecorationPosition.background:
+        paintDecoration();
+        context.paintChild(child!, offset);
+      case DecorationPosition.foreground:
+        context.paintChild(child!, offset);
+        paintDecoration();
     }
   }
 }

packages/flutter/lib/src/rendering/editable.dart

@@ -67,14 +67,11 @@ class TextSelectionPoint {
 
   @override
   String toString() {
-    switch (direction) {
-      case TextDirection.ltr:
-        return '$point-ltr';
-      case TextDirection.rtl:
-        return '$point-rtl';
-      case null:
-        return '$point';
-    }
+    return switch (direction) {
+      TextDirection.ltr => '$point-ltr',
+      TextDirection.rtl => '$point-rtl',
+      null => '$point',
+    };
   }
 
   @override
@@ -1686,32 +1683,26 @@ class RenderEditable extends RenderBox with RelayoutWhenSystemFontsChangeMixin,
   Axis get _viewportAxis => _isMultiline ? Axis.vertical : Axis.horizontal;
 
   Offset get _paintOffset {
-    switch (_viewportAxis) {
-      case Axis.horizontal:
-        return Offset(-offset.pixels, 0.0);
-      case Axis.vertical:
-        return Offset(0.0, -offset.pixels);
-    }
+    return switch (_viewportAxis) {
+      Axis.horizontal => Offset(-offset.pixels, 0.0),
+      Axis.vertical   => Offset(0.0, -offset.pixels),
+    };
   }
 
   double get _viewportExtent {
     assert(hasSize);
-    switch (_viewportAxis) {
-      case Axis.horizontal:
-        return size.width;
-      case Axis.vertical:
-        return size.height;
-    }
+    return switch (_viewportAxis) {
+      Axis.horizontal => size.width,
+      Axis.vertical   => size.height,
+    };
   }
 
   double _getMaxScrollExtent(Size contentSize) {
     assert(hasSize);
-    switch (_viewportAxis) {
-      case Axis.horizontal:
-        return math.max(0.0, contentSize.width - size.width);
-      case Axis.vertical:
-        return math.max(0.0, contentSize.height - size.height);
-    }
+    return switch (_viewportAxis) {
+      Axis.horizontal => math.max(0.0, contentSize.width - size.width),
+      Axis.vertical   => math.max(0.0, contentSize.height - size.height),
+    };
   }
 
   // We need to check the paint offset here because during animation, the start of

packages/flutter/lib/src/rendering/list_body.dart

@@ -252,42 +252,34 @@ class RenderListBody extends RenderBox
 
   @override
   double computeMinIntrinsicWidth(double height) {
-    switch (mainAxis) {
-      case Axis.horizontal:
-        return _getIntrinsicMainAxis((RenderBox child) => child.getMinIntrinsicWidth(height));
-      case Axis.vertical:
-        return _getIntrinsicCrossAxis((RenderBox child) => child.getMinIntrinsicWidth(height));
-    }
+    return switch (mainAxis) {
+      Axis.horizontal => _getIntrinsicMainAxis((RenderBox child) => child.getMinIntrinsicWidth(height)),
+      Axis.vertical  => _getIntrinsicCrossAxis((RenderBox child) => child.getMinIntrinsicWidth(height)),
+    };
   }
 
   @override
   double computeMaxIntrinsicWidth(double height) {
-    switch (mainAxis) {
-      case Axis.horizontal:
-        return _getIntrinsicMainAxis((RenderBox child) => child.getMaxIntrinsicWidth(height));
-      case Axis.vertical:
-        return _getIntrinsicCrossAxis((RenderBox child) => child.getMaxIntrinsicWidth(height));
-    }
+    return switch (mainAxis) {
+      Axis.horizontal => _getIntrinsicMainAxis((RenderBox child) => child.getMaxIntrinsicWidth(height)),
+      Axis.vertical  => _getIntrinsicCrossAxis((RenderBox child) => child.getMaxIntrinsicWidth(height)),
+    };
   }
 
   @override
   double computeMinIntrinsicHeight(double width) {
-    switch (mainAxis) {
-      case Axis.horizontal:
-        return _getIntrinsicMainAxis((RenderBox child) => child.getMinIntrinsicHeight(width));
-      case Axis.vertical:
-        return _getIntrinsicCrossAxis((RenderBox child) => child.getMinIntrinsicHeight(width));
-    }
+    return switch (mainAxis) {
+      Axis.horizontal => _getIntrinsicMainAxis((RenderBox child) => child.getMinIntrinsicHeight(width)),
+      Axis.vertical  => _getIntrinsicCrossAxis((RenderBox child) => child.getMinIntrinsicHeight(width)),
+    };
   }
 
   @override
   double computeMaxIntrinsicHeight(double width) {
-    switch (mainAxis) {
-      case Axis.horizontal:
-        return _getIntrinsicMainAxis((RenderBox child) => child.getMaxIntrinsicHeight(width));
-      case Axis.vertical:
-        return _getIntrinsicCrossAxis((RenderBox child) => child.getMaxIntrinsicHeight(width));
-    }
+    return switch (mainAxis) {
+      Axis.horizontal => _getIntrinsicMainAxis((RenderBox child) => child.getMaxIntrinsicHeight(width)),
+      Axis.vertical  => _getIntrinsicCrossAxis((RenderBox child) => child.getMaxIntrinsicHeight(width)),
+    };
   }
 
   @override

packages/flutter/lib/src/rendering/paragraph.dart

@@ -843,15 +843,10 @@ class RenderParagraph extends RenderBox with ContainerRenderObjectMixin<RenderBo
             locale: locale,
           )..layout();
           if (didOverflowWidth) {
-            double fadeEnd, fadeStart;
-            switch (textDirection) {
-              case TextDirection.rtl:
-                fadeEnd = 0.0;
-                fadeStart = fadeSizePainter.width;
-              case TextDirection.ltr:
-                fadeEnd = size.width;
-                fadeStart = fadeEnd - fadeSizePainter.width;
-            }
+            final (double fadeStart, double fadeEnd) = switch (textDirection) {
+              TextDirection.rtl => (fadeSizePainter.width, 0.0),
+              TextDirection.ltr => (size.width - fadeSizePainter.width, size.width),
+            };
             _overflowShader = ui.Gradient.linear(
               Offset(fadeStart, 0.0),
               Offset(fadeEnd, 0.0),

packages/flutter/lib/src/rendering/proxy_box.dart

@@ -1958,12 +1958,10 @@ class RenderPhysicalModel extends _RenderPhysicalModelBase<RRect> {
   RRect get _defaultClip {
     assert(hasSize);
     final Rect rect = Offset.zero & size;
-    switch (_shape) {
-      case BoxShape.rectangle:
-        return (borderRadius ?? BorderRadius.zero).toRRect(rect);
-      case BoxShape.circle:
-        return RRect.fromRectXY(rect, rect.width / 2, rect.height / 2);
-    }
+    return switch (_shape) {
+      BoxShape.rectangle => (borderRadius ?? BorderRadius.zero).toRRect(rect),
+      BoxShape.circle => RRect.fromRectXY(rect, rect.width / 2, rect.height / 2),
+    };
   }
 
   @override

packages/flutter/lib/src/rendering/shifted_box.dart

@@ -671,25 +671,21 @@ class RenderConstrainedOverflowBox extends RenderAligningShiftedBox {
 
   @override
   bool get sizedByParent {
-    switch (fit) {
-      case OverflowBoxFit.max:
-        return true;
-      case OverflowBoxFit.deferToChild:
-        // If deferToChild, the size will be as small as its child when non-overflowing,
-        // thus it cannot be sizedByParent.
-        return false;
-    }
+    return switch (fit) {
+      OverflowBoxFit.max => true,
+      // If deferToChild, the size will be as small as its child when non-overflowing,
+      // thus it cannot be sizedByParent.
+      OverflowBoxFit.deferToChild => false,
+    };
   }
 
   @override
   @protected
   Size computeDryLayout(covariant BoxConstraints constraints) {
-    switch (fit) {
-      case OverflowBoxFit.max:
-        return constraints.biggest;
-      case OverflowBoxFit.deferToChild:
-        return child?.getDryLayout(constraints) ?? constraints.smallest;
-    }
+    return switch (fit) {
+      OverflowBoxFit.max => constraints.biggest,
+      OverflowBoxFit.deferToChild => child?.getDryLayout(constraints) ?? constraints.smallest,
+    };
   }
 
   @override

packages/flutter/lib/src/rendering/sliver.dart

@@ -150,12 +150,10 @@ enum GrowthDirection {
 /// [AxisDirection] and a [GrowthDirection] and wish to compute the
 /// [AxisDirection] in which growth will occur.
 AxisDirection applyGrowthDirectionToAxisDirection(AxisDirection axisDirection, GrowthDirection growthDirection) {
-  switch (growthDirection) {
-    case GrowthDirection.forward:
-      return axisDirection;
-    case GrowthDirection.reverse:
-      return flipAxisDirection(axisDirection);
-  }
+  return switch (growthDirection) {
+    GrowthDirection.forward => axisDirection,
+    GrowthDirection.reverse => flipAxisDirection(axisDirection),
+  };
 }
 
 /// Flips the [ScrollDirection] if the [GrowthDirection] is
@@ -169,12 +167,10 @@ AxisDirection applyGrowthDirectionToAxisDirection(AxisDirection axisDirection, G
 /// [ScrollDirection] and a [GrowthDirection] and wish to compute the
 /// [ScrollDirection] in which growth will occur.
 ScrollDirection applyGrowthDirectionToScrollDirection(ScrollDirection scrollDirection, GrowthDirection growthDirection) {
-  switch (growthDirection) {
-    case GrowthDirection.forward:
-      return scrollDirection;
-    case GrowthDirection.reverse:
-      return flipScrollDirection(scrollDirection);
-  }
+  return switch (growthDirection) {
+    GrowthDirection.forward => scrollDirection,
+    GrowthDirection.reverse => flipScrollDirection(scrollDirection),
+  };
 }
 
 /// Immutable layout constraints for [RenderSliver] layout.
@@ -442,19 +438,13 @@ class SliverConstraints extends Constraints {
   /// This can be useful in combination with [axis] to view the [axisDirection]
   /// and [growthDirection] in different terms.
   GrowthDirection get normalizedGrowthDirection {
-    switch (axisDirection) {
-      case AxisDirection.down:
-      case AxisDirection.right:
-        return growthDirection;
-      case AxisDirection.up:
-      case AxisDirection.left:
-        switch (growthDirection) {
-          case GrowthDirection.forward:
-            return GrowthDirection.reverse;
-          case GrowthDirection.reverse:
-            return GrowthDirection.forward;
-        }
+    if (axisDirectionIsReversed(axisDirection)) {
+      return switch (growthDirection) {
+        GrowthDirection.forward => GrowthDirection.reverse,
+        GrowthDirection.reverse => GrowthDirection.forward,
+      };
     }
+    return growthDirection;
   }
 
   @override
@@ -1582,16 +1572,12 @@ abstract class RenderSliver extends RenderObject {
   Size getAbsoluteSizeRelativeToOrigin() {
     assert(geometry != null);
     assert(!debugNeedsLayout);
-    switch (applyGrowthDirectionToAxisDirection(constraints.axisDirection, constraints.growthDirection)) {
-      case AxisDirection.up:
-        return Size(constraints.crossAxisExtent, -geometry!.paintExtent);
-      case AxisDirection.right:
-        return Size(geometry!.paintExtent, constraints.crossAxisExtent);
-      case AxisDirection.down:
-        return Size(constraints.crossAxisExtent, geometry!.paintExtent);
-      case AxisDirection.left:
-        return Size(-geometry!.paintExtent, constraints.crossAxisExtent);
-    }
+    return switch (applyGrowthDirectionToAxisDirection(constraints.axisDirection, constraints.growthDirection)) {
+      AxisDirection.up    => Size(constraints.crossAxisExtent, -geometry!.paintExtent),
+      AxisDirection.down  => Size(constraints.crossAxisExtent,  geometry!.paintExtent),
+      AxisDirection.left  => Size(-geometry!.paintExtent, constraints.crossAxisExtent),
+      AxisDirection.right => Size(geometry!.paintExtent,  constraints.crossAxisExtent),
+    };
   }
 
   /// This returns the absolute [Size] of the sliver.
@@ -1843,16 +1829,12 @@ abstract class RenderSliverSingleBoxAdapter extends RenderSliver with RenderObje
   @protected
   void setChildParentData(RenderObject child, SliverConstraints constraints, SliverGeometry geometry) {
     final SliverPhysicalParentData childParentData = child.parentData! as SliverPhysicalParentData;
-    switch (applyGrowthDirectionToAxisDirection(constraints.axisDirection, constraints.growthDirection)) {
-      case AxisDirection.up:
-        childParentData.paintOffset = Offset(0.0, -(geometry.scrollExtent - (geometry.paintExtent + constraints.scrollOffset)));
-      case AxisDirection.right:
-        childParentData.paintOffset = Offset(-constraints.scrollOffset, 0.0);
-      case AxisDirection.down:
-        childParentData.paintOffset = Offset(0.0, -constraints.scrollOffset);
-      case AxisDirection.left:
-        childParentData.paintOffset = Offset(-(geometry.scrollExtent - (geometry.paintExtent + constraints.scrollOffset)), 0.0);
-    }
+    childParentData.paintOffset = switch (applyGrowthDirectionToAxisDirection(constraints.axisDirection, constraints.growthDirection)) {
+      AxisDirection.up    => Offset(0.0, geometry.paintExtent + constraints.scrollOffset - geometry.scrollExtent),
+      AxisDirection.left  => Offset(geometry.paintExtent + constraints.scrollOffset - geometry.scrollExtent, 0.0),
+      AxisDirection.right => Offset(-constraints.scrollOffset, 0.0),
+      AxisDirection.down  => Offset(0.0, -constraints.scrollOffset),
+    };
   }
 
   @override
@@ -1911,13 +1893,10 @@ class RenderSliverToBoxAdapter extends RenderSliverSingleBoxAdapter {
     }
     final SliverConstraints constraints = this.constraints;
     child!.layout(constraints.asBoxConstraints(), parentUsesSize: true);
-    final double childExtent;
-    switch (constraints.axis) {
-      case Axis.horizontal:
-        childExtent = child!.size.width;
-      case Axis.vertical:
-        childExtent = child!.size.height;
-    }
+    final double childExtent = switch (constraints.axis) {
+      Axis.horizontal => child!.size.width,
+      Axis.vertical   => child!.size.height,
+    };
     final double paintedChildSize = calculatePaintOffset(constraints, from: 0.0, to: childExtent);
     final double cacheExtent = calculateCacheOffset(constraints, from: 0.0, to: childExtent);
 

packages/flutter/lib/src/rendering/sliver_fill.dart

@@ -138,13 +138,10 @@ class RenderSliverFillRemaining extends RenderSliverSingleBoxAdapter {
     double extent = constraints.viewportMainAxisExtent - constraints.precedingScrollExtent;
 
     if (child != null) {
-      final double childExtent;
-      switch (constraints.axis) {
-        case Axis.horizontal:
-          childExtent = child!.getMaxIntrinsicWidth(constraints.crossAxisExtent);
-        case Axis.vertical:
-          childExtent = child!.getMaxIntrinsicHeight(constraints.crossAxisExtent);
-      }
+      final double childExtent = switch (constraints.axis) {
+        Axis.horizontal => child!.getMaxIntrinsicWidth(constraints.crossAxisExtent),
+        Axis.vertical  => child!.getMaxIntrinsicHeight(constraints.crossAxisExtent),
+      };
 
       // If the childExtent is greater than the computed extent, we want to use
       // that instead of potentially cutting off the child. This allows us to
@@ -213,13 +210,10 @@ class RenderSliverFillRemainingAndOverscroll extends RenderSliverSingleBoxAdapte
     double maxExtent = constraints.remainingPaintExtent - math.min(constraints.overlap, 0.0);
 
     if (child != null) {
-      final double childExtent;
-      switch (constraints.axis) {
-        case Axis.horizontal:
-          childExtent = child!.getMaxIntrinsicWidth(constraints.crossAxisExtent);
-        case Axis.vertical:
-          childExtent = child!.getMaxIntrinsicHeight(constraints.crossAxisExtent);
-      }
+      final double childExtent = switch (constraints.axis) {
+        Axis.horizontal => child!.getMaxIntrinsicWidth(constraints.crossAxisExtent),
+        Axis.vertical  => child!.getMaxIntrinsicHeight(constraints.crossAxisExtent),
+      };
 
       // If the childExtent is greater than the computed extent, we want to use
       // that instead of potentially cutting off the child. This allows us to

packages/flutter/lib/src/rendering/sliver_group.dart

@@ -110,12 +110,10 @@ class RenderSliverCrossAxisGroup extends RenderSliver with ContainerRenderObject
         : 0.0;
       final double childExtent = child.geometry!.crossAxisExtent ?? extentPerFlexValue * (childParentData.crossAxisFlex ?? 0);
       // Set child parent data.
-      switch (constraints.axis) {
-        case Axis.vertical:
-          childParentData.paintOffset = Offset(offset, -paintCorrection);
-        case Axis.horizontal:
-          childParentData.paintOffset = Offset(-paintCorrection, offset);
-      }
+      childParentData.paintOffset = switch (constraints.axis) {
+        Axis.vertical   => Offset(offset, -paintCorrection),
+        Axis.horizontal => Offset(-paintCorrection, offset),
+      };
       offset += childExtent;
       child = childAfter(child);
     }
@@ -229,14 +227,11 @@ class RenderSliverMainAxisGroup extends RenderSliver with ContainerRenderObjectM
 
   @override
   double childMainAxisPosition(RenderSliver child) {
-    switch (constraints.axisDirection) {
-      case AxisDirection.up:
-      case AxisDirection.down:
-        return (child.parentData! as SliverPhysicalParentData).paintOffset.dy;
-      case AxisDirection.left:
-      case AxisDirection.right:
-        return (child.parentData! as SliverPhysicalParentData).paintOffset.dx;
-    }
+    final Offset paintOffset = (child.parentData! as SliverPhysicalParentData).paintOffset;
+    return switch (constraints.axis) {
+      Axis.horizontal => paintOffset.dx,
+      Axis.vertical   => paintOffset.dy,
+    };
   }
 
   @override
@@ -269,12 +264,10 @@ class RenderSliverMainAxisGroup extends RenderSliver with ContainerRenderObjectM
       );
       final SliverGeometry childLayoutGeometry = child.geometry!;
       final SliverPhysicalParentData childParentData = child.parentData! as SliverPhysicalParentData;
-      switch (constraints.axis) {
-        case Axis.vertical:
-          childParentData.paintOffset = Offset(0.0, beforeOffsetPaintExtent);
-        case Axis.horizontal:
-          childParentData.paintOffset = Offset(beforeOffsetPaintExtent, 0.0);
-      }
+      childParentData.paintOffset = switch (constraints.axis) {
+        Axis.vertical   => Offset(0.0, beforeOffsetPaintExtent),
+        Axis.horizontal => Offset(beforeOffsetPaintExtent, 0.0),
+      };
       offset += childLayoutGeometry.scrollExtent;
       maxPaintExtent += child.geometry!.maxPaintExtent;
       child = childAfter(child);
@@ -304,12 +297,10 @@ class RenderSliverMainAxisGroup extends RenderSliver with ContainerRenderObjectM
       final double remainingExtent = totalScrollExtent - constraints.scrollOffset;
       if (childLayoutGeometry.paintExtent > remainingExtent) {
         final double paintCorrection = childLayoutGeometry.paintExtent - remainingExtent;
-        switch (constraints.axis) {
-          case Axis.vertical:
-            childParentData.paintOffset = Offset(0.0, beforeOffsetPaintExtent - paintCorrection);
-          case Axis.horizontal:
-            childParentData.paintOffset = Offset(beforeOffsetPaintExtent - paintCorrection, 0.0);
-        }
+        childParentData.paintOffset = switch (constraints.axis) {
+          Axis.vertical   => Offset(0.0, beforeOffsetPaintExtent - paintCorrection),
+          Axis.horizontal => Offset(beforeOffsetPaintExtent - paintCorrection, 0.0),
+        };
       }
       offset += child.geometry!.scrollExtent;
       child = childAfter(child);

packages/flutter/lib/src/rendering/sliver_multi_box_adaptor.dart

@@ -602,12 +602,10 @@ abstract class RenderSliverMultiBoxAdaptor extends RenderSliver
   @protected
   double paintExtentOf(RenderBox child) {
     assert(child.hasSize);
-    switch (constraints.axis) {
-      case Axis.horizontal:
-        return child.size.width;
-      case Axis.vertical:
-        return child.size.height;
-    }
+    return switch (constraints.axis) {
+      Axis.horizontal => child.size.width,
+      Axis.vertical   => child.size.height,
+    };
   }
 
   @override

packages/flutter/lib/src/rendering/sliver_persistent_header.dart

@@ -152,12 +152,10 @@ abstract class RenderSliverPersistentHeader extends RenderSliver with RenderObje
       return 0.0;
     }
     assert(child!.hasSize);
-    switch (constraints.axis) {
-      case Axis.vertical:
-        return child!.size.height;
-      case Axis.horizontal:
-        return child!.size.width;
-    }
+    return switch (constraints.axis) {
+      Axis.vertical => child!.size.height,
+      Axis.horizontal => child!.size.width,
+    };
   }
 
   bool _needsUpdateChild = true;
@@ -298,16 +296,12 @@ abstract class RenderSliverPersistentHeader extends RenderSliver with RenderObje
   @override
   void paint(PaintingContext context, Offset offset) {
     if (child != null && geometry!.visible) {
-      switch (applyGrowthDirectionToAxisDirection(constraints.axisDirection, constraints.growthDirection)) {
-        case AxisDirection.up:
-          offset += Offset(0.0, geometry!.paintExtent - childMainAxisPosition(child!) - childExtent);
-        case AxisDirection.down:
-          offset += Offset(0.0, childMainAxisPosition(child!));
-        case AxisDirection.left:
-          offset += Offset(geometry!.paintExtent - childMainAxisPosition(child!) - childExtent, 0.0);
-        case AxisDirection.right:
-          offset += Offset(childMainAxisPosition(child!), 0.0);
-      }
+      offset += switch (applyGrowthDirectionToAxisDirection(constraints.axisDirection, constraints.growthDirection)) {
+        AxisDirection.up    => Offset(0.0, geometry!.paintExtent - childMainAxisPosition(child!) - childExtent),
+        AxisDirection.left  => Offset(geometry!.paintExtent - childMainAxisPosition(child!) - childExtent, 0.0),
+        AxisDirection.right => Offset(childMainAxisPosition(child!), 0.0),
+        AxisDirection.down  => Offset(0.0, childMainAxisPosition(child!)),
+      };
       context.paintChild(child!, offset);
     }
   }
@@ -446,17 +440,12 @@ abstract class RenderSliverPinnedPersistentHeader extends RenderSliverPersistent
       ? MatrixUtils.transformRect(descendant.getTransformTo(this), rect ?? descendant.paintBounds)
       : rect;
 
-    Rect? newRect;
-    switch (applyGrowthDirectionToAxisDirection(constraints.axisDirection, constraints.growthDirection)) {
-      case AxisDirection.up:
-        newRect = _trim(localBounds, bottom: childExtent);
-      case AxisDirection.right:
-        newRect = _trim(localBounds, left: 0);
-      case AxisDirection.down:
-        newRect = _trim(localBounds, top: 0);
-      case AxisDirection.left:
-        newRect = _trim(localBounds, right: childExtent);
-    }
+    final Rect? newRect = switch (applyGrowthDirectionToAxisDirection(constraints.axisDirection, constraints.growthDirection)) {
+      AxisDirection.up    => _trim(localBounds, bottom: childExtent),
+      AxisDirection.left  => _trim(localBounds, right: childExtent),
+      AxisDirection.right => _trim(localBounds, left: 0),
+      AxisDirection.down  => _trim(localBounds, top: 0),
+    };
 
     super.showOnScreen(
       descendant: this,

packages/flutter/lib/src/rendering/stack.dart

@@ -66,17 +66,10 @@ class RelativeRect {
     required double end,
     required double bottom,
   }) {
-    double left;
-    double right;
-    switch (textDirection) {
-      case TextDirection.rtl:
-        left = end;
-        right = start;
-      case TextDirection.ltr:
-        left = start;
-        right = end;
-    }
-
+    final (double left, double right) = switch (textDirection) {
+      TextDirection.rtl => (end, start),
+      TextDirection.ltr => (start, end),
+    };
     return RelativeRect.fromLTRB(left, top, right, bottom);
   }
 

packages/flutter/lib/src/rendering/viewport_offset.dart

@@ -69,14 +69,11 @@ enum ScrollDirection {
 /// (and vice versa) and returns [ScrollDirection.idle] for
 /// [ScrollDirection.idle].
 ScrollDirection flipScrollDirection(ScrollDirection direction) {
-  switch (direction) {
-    case ScrollDirection.idle:
-      return ScrollDirection.idle;
-    case ScrollDirection.forward:
-      return ScrollDirection.reverse;
-    case ScrollDirection.reverse:
-      return ScrollDirection.forward;
-  }
+  return switch (direction) {
+    ScrollDirection.idle    => ScrollDirection.idle,
+    ScrollDirection.forward => ScrollDirection.reverse,
+    ScrollDirection.reverse => ScrollDirection.forward,
+  };
 }
 
 /// Which part of the content inside the viewport should be visible.

packages/flutter/lib/src/rendering/wrap.dart

@@ -454,42 +454,33 @@ class RenderWrap extends RenderBox
   }
 
   double _getMainAxisExtent(Size childSize) {
-    switch (direction) {
-      case Axis.horizontal:
-        return childSize.width;
-      case Axis.vertical:
-        return childSize.height;
-    }
+    return switch (direction) {
+      Axis.horizontal => childSize.width,
+      Axis.vertical   => childSize.height,
+    };
   }
 
   double _getCrossAxisExtent(Size childSize) {
-    switch (direction) {
-      case Axis.horizontal:
-        return childSize.height;
-      case Axis.vertical:
-        return childSize.width;
-    }
+    return switch (direction) {
+      Axis.horizontal => childSize.height,
+      Axis.vertical   => childSize.width,
+    };
   }
 
   Offset _getOffset(double mainAxisOffset, double crossAxisOffset) {
-    switch (direction) {
-      case Axis.horizontal:
-        return Offset(mainAxisOffset, crossAxisOffset);
-      case Axis.vertical:
-        return Offset(crossAxisOffset, mainAxisOffset);
-    }
+    return switch (direction) {
+      Axis.horizontal => Offset(mainAxisOffset, crossAxisOffset),
+      Axis.vertical   => Offset(crossAxisOffset, mainAxisOffset),
+    };
   }
 
   double _getChildCrossAxisOffset(bool flipCrossAxis, double runCrossAxisExtent, double childCrossAxisExtent) {
     final double freeSpace = runCrossAxisExtent - childCrossAxisExtent;
-    switch (crossAxisAlignment) {
-      case WrapCrossAlignment.start:
-        return flipCrossAxis ? freeSpace : 0.0;
-      case WrapCrossAlignment.end:
-        return flipCrossAxis ? 0.0 : freeSpace;
-      case WrapCrossAlignment.center:
-        return freeSpace / 2.0;
-    }
+    return switch (crossAxisAlignment) {
+      WrapCrossAlignment.start  => flipCrossAxis ? freeSpace : 0.0,
+      WrapCrossAlignment.end    => flipCrossAxis ? 0.0 : freeSpace,
+      WrapCrossAlignment.center => freeSpace / 2.0,
+    };
   }
 
   bool _hasVisualOverflow = false;
@@ -501,16 +492,10 @@ class RenderWrap extends RenderBox
   }
 
   Size _computeDryLayout(BoxConstraints constraints, [ChildLayouter layoutChild = ChildLayoutHelper.dryLayoutChild]) {
-    final BoxConstraints childConstraints;
-    double mainAxisLimit = 0.0;
-    switch (direction) {
-      case Axis.horizontal:
-        childConstraints = BoxConstraints(maxWidth: constraints.maxWidth);
-        mainAxisLimit = constraints.maxWidth;
-      case Axis.vertical:
-        childConstraints = BoxConstraints(maxHeight: constraints.maxHeight);
-        mainAxisLimit = constraints.maxHeight;
-    }
+    final (BoxConstraints childConstraints, double mainAxisLimit) = switch (direction) {
+      Axis.horizontal => (BoxConstraints(maxWidth: constraints.maxWidth), constraints.maxWidth),
+      Axis.vertical => (BoxConstraints(maxHeight: constraints.maxHeight), constraints.maxHeight),
+    };
 
     double mainAxisExtent = 0.0;
     double crossAxisExtent = 0.0;
@@ -541,12 +526,10 @@ class RenderWrap extends RenderBox
     crossAxisExtent += runCrossAxisExtent;
     mainAxisExtent = math.max(mainAxisExtent, runMainAxisExtent);
 
-    switch (direction) {
-      case Axis.horizontal:
-        return constraints.constrain(Size(mainAxisExtent, crossAxisExtent));
-      case Axis.vertical:
-        return constraints.constrain(Size(crossAxisExtent, mainAxisExtent));
-    }
+    return constraints.constrain(switch (direction) {
+      Axis.horizontal => Size(mainAxisExtent, crossAxisExtent),
+      Axis.vertical   => Size(crossAxisExtent, mainAxisExtent),
+    });
   }
 
   @override