diff --git a/packages/flutter/lib/src/painting/_network_image_io.dart b/packages/flutter/lib/src/painting/_network_image_io.dart
index aa5fc2681a..574188f65a 100644
--- a/packages/flutter/lib/src/painting/_network_image_io.dart
+++ b/packages/flutter/lib/src/painting/_network_image_io.dart
@@ -44,7 +44,7 @@ class NetworkImage extends image_provider.ImageProvider<image_provider.NetworkIm
     final StreamController<ImageChunkEvent> chunkEvents = StreamController<ImageChunkEvent>();
 
     return MultiFrameImageStreamCompleter(
-      codec: _loadAsync(key, chunkEvents, decode),
+      codec: _loadAsync(key as NetworkImage, chunkEvents, decode),
       chunkEvents: chunkEvents.stream,
       scale: key.scale,
       informationCollector: () {
@@ -111,9 +111,9 @@ class NetworkImage extends image_provider.ImageProvider<image_provider.NetworkIm
   bool operator ==(dynamic other) {
     if (other.runtimeType != runtimeType)
       return false;
-    final NetworkImage typedOther = other;
-    return url == typedOther.url
-        && scale == typedOther.scale;
+    return other is NetworkImage
+        && other.url == url
+        && other.scale == scale;
   }
 
   @override
diff --git a/packages/flutter/lib/src/painting/_network_image_web.dart b/packages/flutter/lib/src/painting/_network_image_web.dart
index 2ad8d73f29..51bae08ff0 100644
--- a/packages/flutter/lib/src/painting/_network_image_web.dart
+++ b/packages/flutter/lib/src/painting/_network_image_web.dart
@@ -38,12 +38,12 @@ class NetworkImage extends image_provider.ImageProvider<image_provider.NetworkIm
   @override
   ImageStreamCompleter load(image_provider.NetworkImage key, image_provider.DecoderCallback decode) {
     return MultiFrameImageStreamCompleter(
-      codec: _loadAsync(key, decode),
+      codec: _loadAsync(key as NetworkImage, decode),
       scale: key.scale,
       informationCollector: () {
         return <DiagnosticsNode>[
           DiagnosticsProperty<image_provider.ImageProvider>('Image provider', this),
-          DiagnosticsProperty<NetworkImage>('Image key', key),
+          DiagnosticsProperty<NetworkImage>('Image key', key as NetworkImage),
         ];
       },
     );
@@ -55,13 +55,13 @@ class NetworkImage extends image_provider.ImageProvider<image_provider.NetworkIm
   // Web does not support decoding network images to a specified size. The decode parameter
   // here is ignored and the web-only `ui.webOnlyInstantiateImageCodecFromUrl` will be used
   // directly in place of the typical `instantiateImageCodec` method.
-  Future<ui.Codec> _loadAsync(NetworkImage key, image_provider.DecoderCallback decode) async {
+  Future<ui.Codec> _loadAsync(NetworkImage key, image_provider.DecoderCallback decode) {
     assert(key == this);
 
     final Uri resolved = Uri.base.resolve(key.url);
     // This API only exists in the web engine implementation and is not
     // contained in the analyzer summary for Flutter.
-    return ui.webOnlyInstantiateImageCodecFromUrl(resolved); // ignore: undefined_function
+    return ui.webOnlyInstantiateImageCodecFromUrl(resolved) as Future<ui.Codec>; // ignore: undefined_function
   }
 
   @override
@@ -69,8 +69,9 @@ class NetworkImage extends image_provider.ImageProvider<image_provider.NetworkIm
     if (other.runtimeType != runtimeType) {
       return false;
     }
-    final NetworkImage typedOther = other;
-    return url == typedOther.url && scale == typedOther.scale;
+    return other is NetworkImage
+        && other.url == url
+        && other.scale == scale;
   }
 
   @override
diff --git a/packages/flutter/lib/src/painting/alignment.dart b/packages/flutter/lib/src/painting/alignment.dart
index 5f017c4906..9ddf740a9c 100644
--- a/packages/flutter/lib/src/painting/alignment.dart
+++ b/packages/flutter/lib/src/painting/alignment.dart
@@ -127,12 +127,10 @@ abstract class AlignmentGeometry {
 
   @override
   bool operator ==(dynamic other) {
-    if (other is! AlignmentGeometry)
-      return false;
-    final AlignmentGeometry typedOther = other;
-    return _x == typedOther._x &&
-           _start == typedOther._start &&
-           _y == typedOther._y;
+    return other is AlignmentGeometry
+        && other._x == _x
+        && other._start == _start
+        && other._y == _y;
   }
 
   @override
diff --git a/packages/flutter/lib/src/painting/beveled_rectangle_border.dart b/packages/flutter/lib/src/painting/beveled_rectangle_border.dart
index 941ffe9d2a..bb8fab0025 100644
--- a/packages/flutter/lib/src/painting/beveled_rectangle_border.dart
+++ b/packages/flutter/lib/src/painting/beveled_rectangle_border.dart
@@ -136,9 +136,9 @@ class BeveledRectangleBorder extends ShapeBorder {
   bool operator ==(dynamic other) {
     if (runtimeType != other.runtimeType)
       return false;
-    final BeveledRectangleBorder typedOther = other;
-    return side == typedOther.side
-        && borderRadius == typedOther.borderRadius;
+    return other is BeveledRectangleBorder
+        && other.side == side
+        && other.borderRadius == borderRadius;
   }
 
   @override
diff --git a/packages/flutter/lib/src/painting/binding.dart b/packages/flutter/lib/src/painting/binding.dart
index 2b04098abc..8adac804f8 100644
--- a/packages/flutter/lib/src/painting/binding.dart
+++ b/packages/flutter/lib/src/painting/binding.dart
@@ -113,8 +113,8 @@ mixin PaintingBinding on BindingBase, ServicesBinding {
   @override
   Future<void> handleSystemMessage(Object systemMessage) async {
     await super.handleSystemMessage(systemMessage);
-    final Map<String, dynamic> message = systemMessage;
-    final String type = message['type'];
+    final Map<String, dynamic> message = systemMessage as Map<String, dynamic>;
+    final String type = message['type'] as String;
     switch (type) {
       case 'fontsChange':
         _systemFonts.notifyListeners();
diff --git a/packages/flutter/lib/src/painting/border_radius.dart b/packages/flutter/lib/src/painting/border_radius.dart
index 816d094796..f6a2c8af50 100644
--- a/packages/flutter/lib/src/painting/border_radius.dart
+++ b/packages/flutter/lib/src/painting/border_radius.dart
@@ -244,15 +244,15 @@ abstract class BorderRadiusGeometry {
       return true;
     if (runtimeType != other.runtimeType)
       return false;
-    final BorderRadiusGeometry typedOther = other;
-    return _topLeft == typedOther._topLeft
-        && _topRight == typedOther._topRight
-        && _bottomLeft == typedOther._bottomLeft
-        && _bottomRight == typedOther._bottomRight
-        && _topStart == typedOther._topStart
-        && _topEnd == typedOther._topEnd
-        && _bottomStart == typedOther._bottomStart
-        && _bottomEnd == typedOther._bottomEnd;
+    return other is BorderRadiusGeometry
+        && other._topLeft == _topLeft
+        && other._topRight == _topRight
+        && other._bottomLeft == _bottomLeft
+        && other._bottomRight == _bottomRight
+        && other._topStart == _topStart
+        && other._topEnd == _topEnd
+        && other._bottomStart == _bottomStart
+        && other._bottomEnd == _bottomEnd;
   }
 
   @override
diff --git a/packages/flutter/lib/src/painting/borders.dart b/packages/flutter/lib/src/painting/borders.dart
index 36322235a9..5725e3e381 100644
--- a/packages/flutter/lib/src/painting/borders.dart
+++ b/packages/flutter/lib/src/painting/borders.dart
@@ -257,10 +257,10 @@ class BorderSide {
       return true;
     if (runtimeType != other.runtimeType)
       return false;
-    final BorderSide typedOther = other;
-    return color == typedOther.color &&
-           width == typedOther.width &&
-           style == typedOther.style;
+    return other is BorderSide
+        && other.color == color
+        && other.width == width
+        && other.style == style;
   }
 
   @override
@@ -615,16 +615,8 @@ class _CompoundBorder extends ShapeBorder {
       return true;
     if (runtimeType != other.runtimeType)
       return false;
-    final _CompoundBorder typedOther = other;
-    if (borders == typedOther.borders)
-      return true;
-    if (borders.length != typedOther.borders.length)
-      return false;
-    for (int index = 0; index < borders.length; index += 1) {
-      if (borders[index] != typedOther.borders[index])
-        return false;
-    }
-    return true;
+    return other is _CompoundBorder
+        && listEquals<ShapeBorder>(other.borders, borders);
   }
 
   @override
diff --git a/packages/flutter/lib/src/painting/box_border.dart b/packages/flutter/lib/src/painting/box_border.dart
index b6c7ce15a7..75fcbb31f6 100644
--- a/packages/flutter/lib/src/painting/box_border.dart
+++ b/packages/flutter/lib/src/painting/box_border.dart
@@ -105,9 +105,9 @@ abstract class BoxBorder extends ShapeBorder {
   static BoxBorder lerp(BoxBorder a, BoxBorder b, double t) {
     assert(t != null);
     if ((a is Border || a == null) && (b is Border || b == null))
-      return Border.lerp(a, b, t);
+      return Border.lerp(a as Border, b as Border, t);
     if ((a is BorderDirectional || a == null) && (b is BorderDirectional || b == null))
-      return BorderDirectional.lerp(a, b, t);
+      return BorderDirectional.lerp(a as BorderDirectional, b as BorderDirectional, t);
     if (b is Border && a is BorderDirectional) {
       final BoxBorder c = b;
       b = a;
@@ -402,14 +402,12 @@ class Border extends BoxBorder {
 
   @override
   Border add(ShapeBorder other, { bool reversed = false }) {
-    if (other is! Border)
-      return null;
-    final Border typedOther = other;
-    if (BorderSide.canMerge(top, typedOther.top) &&
-        BorderSide.canMerge(right, typedOther.right) &&
-        BorderSide.canMerge(bottom, typedOther.bottom) &&
-        BorderSide.canMerge(left, typedOther.left)) {
-      return Border.merge(this, typedOther);
+    if (other is Border &&
+        BorderSide.canMerge(top, other.top) &&
+        BorderSide.canMerge(right, other.right) &&
+        BorderSide.canMerge(bottom, other.bottom) &&
+        BorderSide.canMerge(left, other.left)) {
+      return Border.merge(this, other);
     }
     return null;
   }
@@ -521,11 +519,11 @@ class Border extends BoxBorder {
       return true;
     if (runtimeType != other.runtimeType)
       return false;
-    final Border typedOther = other;
-    return top == typedOther.top &&
-           right == typedOther.right &&
-           bottom == typedOther.bottom &&
-           left == typedOther.left;
+    return other is Border
+        && other.top == top
+        && other.right == right
+        && other.bottom == bottom
+        && other.left == left;
   }
 
   @override
@@ -825,11 +823,11 @@ class BorderDirectional extends BoxBorder {
       return true;
     if (runtimeType != other.runtimeType)
       return false;
-    final BorderDirectional typedOther = other;
-    return top == typedOther.top &&
-           start == typedOther.start &&
-           end == typedOther.end &&
-           bottom == typedOther.bottom;
+    return other is BorderDirectional
+        && other.top == top
+        && other.start == start
+        && other.end == end
+        && other.bottom == bottom;
   }
 
   @override
diff --git a/packages/flutter/lib/src/painting/box_decoration.dart b/packages/flutter/lib/src/painting/box_decoration.dart
index 9bf5851580..bb3b7b4353 100644
--- a/packages/flutter/lib/src/painting/box_decoration.dart
+++ b/packages/flutter/lib/src/painting/box_decoration.dart
@@ -250,7 +250,7 @@ class BoxDecoration extends Decoration {
       return scale(t);
     if (a is BoxDecoration)
       return BoxDecoration.lerp(a, this, t);
-    return super.lerpFrom(a, t);
+    return super.lerpFrom(a, t) as BoxDecoration;
   }
 
   @override
@@ -259,7 +259,7 @@ class BoxDecoration extends Decoration {
       return scale(1.0 - t);
     if (b is BoxDecoration)
       return BoxDecoration.lerp(this, b, t);
-    return super.lerpTo(b, t);
+    return super.lerpTo(b, t) as BoxDecoration;
   }
 
   /// Linearly interpolate between two box decorations.
@@ -314,14 +314,14 @@ class BoxDecoration extends Decoration {
       return true;
     if (runtimeType != other.runtimeType)
       return false;
-    final BoxDecoration typedOther = other;
-    return color == typedOther.color &&
-           image == typedOther.image &&
-           border == typedOther.border &&
-           borderRadius == typedOther.borderRadius &&
-           boxShadow == typedOther.boxShadow &&
-           gradient == typedOther.gradient &&
-           shape == typedOther.shape;
+    return other is BoxDecoration
+        && other.color == color
+        && other.image == image
+        && other.border == border
+        && other.borderRadius == borderRadius
+        && other.boxShadow == boxShadow
+        && other.gradient == gradient
+        && other.shape == shape;
   }
 
   @override
@@ -483,7 +483,7 @@ class _BoxDecorationPainter extends BoxPainter {
       canvas,
       rect,
       shape: _decoration.shape,
-      borderRadius: _decoration.borderRadius,
+      borderRadius: _decoration.borderRadius as BorderRadius,
       textDirection: configuration.textDirection,
     );
   }
diff --git a/packages/flutter/lib/src/painting/box_shadow.dart b/packages/flutter/lib/src/painting/box_shadow.dart
index 560d68c65a..e3d3ea3d8b 100644
--- a/packages/flutter/lib/src/painting/box_shadow.dart
+++ b/packages/flutter/lib/src/painting/box_shadow.dart
@@ -118,11 +118,11 @@ class BoxShadow extends ui.Shadow {
       return true;
     if (runtimeType != other.runtimeType)
       return false;
-    final BoxShadow typedOther = other;
-    return color == typedOther.color &&
-           offset == typedOther.offset &&
-           blurRadius == typedOther.blurRadius &&
-           spreadRadius == typedOther.spreadRadius;
+    return other is BoxShadow
+        && other.color == color
+        && other.offset == offset
+        && other.blurRadius == blurRadius
+        && other.spreadRadius == spreadRadius;
   }
 
   @override
diff --git a/packages/flutter/lib/src/painting/circle_border.dart b/packages/flutter/lib/src/painting/circle_border.dart
index aaebb47dde..1ecefbfdb1 100644
--- a/packages/flutter/lib/src/painting/circle_border.dart
+++ b/packages/flutter/lib/src/painting/circle_border.dart
@@ -84,8 +84,8 @@ class CircleBorder extends ShapeBorder {
   bool operator ==(dynamic other) {
     if (runtimeType != other.runtimeType)
       return false;
-    final CircleBorder typedOther = other;
-    return side == typedOther.side;
+    return other is CircleBorder
+        && other.side == side;
   }
 
   @override
diff --git a/packages/flutter/lib/src/painting/colors.dart b/packages/flutter/lib/src/painting/colors.dart
index 877ad5a8a8..98fea46e41 100644
--- a/packages/flutter/lib/src/painting/colors.dart
+++ b/packages/flutter/lib/src/painting/colors.dart
@@ -206,10 +206,10 @@ class HSVColor {
     if (b == null)
       return a._scaleAlpha(1.0 - t);
     return HSVColor.fromAHSV(
-      lerpDouble(a.alpha, b.alpha, t).clamp(0.0, 1.0),
+      lerpDouble(a.alpha, b.alpha, t).clamp(0.0, 1.0) as double,
       lerpDouble(a.hue, b.hue, t) % 360.0,
-      lerpDouble(a.saturation, b.saturation, t).clamp(0.0, 1.0),
-      lerpDouble(a.value, b.value, t).clamp(0.0, 1.0),
+      lerpDouble(a.saturation, b.saturation, t).clamp(0.0, 1.0) as double,
+      lerpDouble(a.value, b.value, t).clamp(0.0, 1.0) as double,
     );
   }
 
@@ -217,13 +217,11 @@ class HSVColor {
   bool operator ==(dynamic other) {
     if (identical(this, other))
       return true;
-    if (other is! HSVColor)
-      return false;
-    final HSVColor typedOther = other;
-    return typedOther.alpha == alpha
-        && typedOther.hue == hue
-        && typedOther.saturation == saturation
-        && typedOther.value == value;
+    return other is HSVColor
+        && other.alpha == alpha
+        && other.hue == hue
+        && other.saturation == saturation
+        && other.value == value;
   }
 
   @override
@@ -292,7 +290,7 @@ class HSLColor {
     // Saturation can exceed 1.0 with rounding errors, so clamp it.
     final double saturation = lightness == 1.0
       ? 0.0
-      : (delta / (1.0 - (2.0 * lightness - 1.0).abs())).clamp(0.0, 1.0);
+      : ((delta / (1.0 - (2.0 * lightness - 1.0).abs())).clamp(0.0, 1.0) as double);
     return HSLColor.fromAHSL(alpha, hue, saturation, lightness);
   }
 
@@ -392,10 +390,10 @@ class HSLColor {
     if (b == null)
       return a._scaleAlpha(1.0 - t);
     return HSLColor.fromAHSL(
-      lerpDouble(a.alpha, b.alpha, t).clamp(0.0, 1.0),
+      lerpDouble(a.alpha, b.alpha, t).clamp(0.0, 1.0) as double,
       lerpDouble(a.hue, b.hue, t) % 360.0,
-      lerpDouble(a.saturation, b.saturation, t).clamp(0.0, 1.0),
-      lerpDouble(a.lightness, b.lightness, t).clamp(0.0, 1.0),
+      lerpDouble(a.saturation, b.saturation, t).clamp(0.0, 1.0) as double,
+      lerpDouble(a.lightness, b.lightness, t).clamp(0.0, 1.0) as double,
     );
   }
 
@@ -403,13 +401,11 @@ class HSLColor {
   bool operator ==(dynamic other) {
     if (identical(this, other))
       return true;
-    if (other is! HSLColor)
-      return false;
-    final HSLColor typedOther = other;
-    return typedOther.alpha == alpha
-        && typedOther.hue == hue
-        && typedOther.saturation == saturation
-        && typedOther.lightness == lightness;
+    return other is HSLColor
+        && other.alpha == alpha
+        && other.hue == hue
+        && other.saturation == saturation
+        && other.lightness == lightness;
   }
 
   @override
@@ -450,8 +446,9 @@ class ColorSwatch<T> extends Color {
       return true;
     if (other.runtimeType != runtimeType)
       return false;
-    final ColorSwatch<T> typedOther = other;
-    return super == other && _swatch == typedOther._swatch;
+    return super == other
+        && other is ColorSwatch<T>
+        && other._swatch == _swatch;
   }
 
   @override
diff --git a/packages/flutter/lib/src/painting/continuous_rectangle_border.dart b/packages/flutter/lib/src/painting/continuous_rectangle_border.dart
index d53cfedb24..d10b280a2c 100644
--- a/packages/flutter/lib/src/painting/continuous_rectangle_border.dart
+++ b/packages/flutter/lib/src/painting/continuous_rectangle_border.dart
@@ -151,9 +151,9 @@ class ContinuousRectangleBorder extends ShapeBorder {
   bool operator ==(dynamic other) {
     if (runtimeType != other.runtimeType)
       return false;
-    final ContinuousRectangleBorder typedOther = other;
-    return side == typedOther.side
-        && borderRadius == typedOther.borderRadius;
+    return other is ContinuousRectangleBorder
+        && other.side == side
+        && other.borderRadius == borderRadius;
   }
 
   @override
diff --git a/packages/flutter/lib/src/painting/decoration_image.dart b/packages/flutter/lib/src/painting/decoration_image.dart
index db2d6abd41..fff0f06223 100644
--- a/packages/flutter/lib/src/painting/decoration_image.dart
+++ b/packages/flutter/lib/src/painting/decoration_image.dart
@@ -141,14 +141,14 @@ class DecorationImage {
       return true;
     if (runtimeType != other.runtimeType)
       return false;
-    final DecorationImage typedOther = other;
-    return image == typedOther.image
-        && colorFilter == typedOther.colorFilter
-        && fit == typedOther.fit
-        && alignment == typedOther.alignment
-        && centerSlice == typedOther.centerSlice
-        && repeat == typedOther.repeat
-        && matchTextDirection == typedOther.matchTextDirection;
+    return other is DecorationImage
+        && other.image == image
+        && other.colorFilter == colorFilter
+        && other.fit == fit
+        && other.alignment == alignment
+        && other.centerSlice == centerSlice
+        && other.repeat == repeat
+        && other.matchTextDirection == matchTextDirection;
   }
 
   @override
@@ -392,8 +392,8 @@ void paintImage({
       centerSlice.left + inputSize.width - centerSlice.right,
       centerSlice.top + inputSize.height - centerSlice.bottom,
     );
-    outputSize -= sliceBorder;
-    inputSize -= sliceBorder;
+    outputSize = outputSize - sliceBorder as Size;
+    inputSize = inputSize - sliceBorder as Size;
   }
   fit ??= centerSlice == null ? BoxFit.scaleDown : BoxFit.fill;
   assert(centerSlice == null || (fit != BoxFit.none && fit != BoxFit.cover));
diff --git a/packages/flutter/lib/src/painting/edge_insets.dart b/packages/flutter/lib/src/painting/edge_insets.dart
index acf5b346cd..4c2b61a059 100644
--- a/packages/flutter/lib/src/painting/edge_insets.dart
+++ b/packages/flutter/lib/src/painting/edge_insets.dart
@@ -280,15 +280,13 @@ abstract class EdgeInsetsGeometry {
 
   @override
   bool operator ==(dynamic other) {
-    if (other is! EdgeInsetsGeometry)
-      return false;
-    final EdgeInsetsGeometry typedOther = other;
-    return _left == typedOther._left
-        && _right == typedOther._right
-        && _start == typedOther._start
-        && _end == typedOther._end
-        && _top == typedOther._top
-        && _bottom == typedOther._bottom;
+    return other is EdgeInsetsGeometry
+        && other._left == _left
+        && other._right == _right
+        && other._start == _start
+        && other._end == _end
+        && other._top == _top
+        && other._bottom == _bottom;
   }
 
   @override
diff --git a/packages/flutter/lib/src/painting/flutter_logo.dart b/packages/flutter/lib/src/painting/flutter_logo.dart
index 453b5a3d72..59b9da4824 100644
--- a/packages/flutter/lib/src/painting/flutter_logo.dart
+++ b/packages/flutter/lib/src/painting/flutter_logo.dart
@@ -171,7 +171,7 @@ class FlutterLogoDecoration extends Decoration {
       t < 0.5 ? a.style : b.style,
       EdgeInsets.lerp(a.margin, b.margin, t),
       a._position + (b._position - a._position) * t,
-      (a._opacity + (b._opacity - a._opacity) * t).clamp(0.0, 1.0),
+      (a._opacity + (b._opacity - a._opacity) * t).clamp(0.0, 1.0) as double,
     );
   }
 
@@ -180,9 +180,9 @@ class FlutterLogoDecoration extends Decoration {
     assert(debugAssertIsValid());
     if (a == null || a is FlutterLogoDecoration) {
       assert(a == null || a.debugAssertIsValid());
-      return FlutterLogoDecoration.lerp(a, this, t);
+      return FlutterLogoDecoration.lerp(a as FlutterLogoDecoration, this, t);
     }
-    return super.lerpFrom(a, t);
+    return super.lerpFrom(a, t) as FlutterLogoDecoration;
   }
 
   @override
@@ -190,9 +190,9 @@ class FlutterLogoDecoration extends Decoration {
     assert(debugAssertIsValid());
     if (b == null || b is FlutterLogoDecoration) {
       assert(b == null || b.debugAssertIsValid());
-      return FlutterLogoDecoration.lerp(this, b, t);
+      return FlutterLogoDecoration.lerp(this, b as FlutterLogoDecoration, t);
     }
-    return super.lerpTo(b, t);
+    return super.lerpTo(b, t) as FlutterLogoDecoration;
   }
 
   @override
@@ -210,14 +210,12 @@ class FlutterLogoDecoration extends Decoration {
     assert(debugAssertIsValid());
     if (identical(this, other))
       return true;
-    if (other is! FlutterLogoDecoration)
-      return false;
-    final FlutterLogoDecoration typedOther = other;
-    return lightColor == typedOther.lightColor
-        && darkColor == typedOther.darkColor
-        && textColor == typedOther.textColor
-        && _position == typedOther._position
-        && _opacity == typedOther._opacity;
+    return other is FlutterLogoDecoration
+        && other.lightColor == lightColor
+        && other.darkColor == darkColor
+        && other.textColor == textColor
+        && other._position == _position
+        && other._opacity == _opacity;
   }
 
   @override
diff --git a/packages/flutter/lib/src/painting/fractional_offset.dart b/packages/flutter/lib/src/painting/fractional_offset.dart
index f9d249d16b..ef4436187e 100644
--- a/packages/flutter/lib/src/painting/fractional_offset.dart
+++ b/packages/flutter/lib/src/painting/fractional_offset.dart
@@ -137,7 +137,7 @@ class FractionalOffset extends Alignment {
   Alignment operator -(Alignment other) {
     if (other is! FractionalOffset)
       return super - other;
-    final FractionalOffset typedOther = other;
+    final FractionalOffset typedOther = other as FractionalOffset;
     return FractionalOffset(dx - typedOther.dx, dy - typedOther.dy);
   }
 
@@ -145,7 +145,7 @@ class FractionalOffset extends Alignment {
   Alignment operator +(Alignment other) {
     if (other is! FractionalOffset)
       return super + other;
-    final FractionalOffset typedOther = other;
+    final FractionalOffset typedOther = other as FractionalOffset;
     return FractionalOffset(dx + typedOther.dx, dy + typedOther.dy);
   }
 
diff --git a/packages/flutter/lib/src/painting/geometry.dart b/packages/flutter/lib/src/painting/geometry.dart
index ec3b9d4c0c..2b1d665e4b 100644
--- a/packages/flutter/lib/src/painting/geometry.dart
+++ b/packages/flutter/lib/src/painting/geometry.dart
@@ -66,7 +66,7 @@ Offset positionDependentBox({
   if (size.width - margin * 2.0 < childSize.width) {
     x = (size.width - childSize.width) / 2.0;
   } else {
-    final double normalizedTargetX = target.dx.clamp(margin, size.width - margin);
+    final double normalizedTargetX = target.dx.clamp(margin, size.width - margin) as double;
     final double edge = margin + childSize.width / 2.0;
     if (normalizedTargetX < edge) {
       x = margin;
diff --git a/packages/flutter/lib/src/painting/gradient.dart b/packages/flutter/lib/src/painting/gradient.dart
index bcdd83e39f..3ff92e05f7 100644
--- a/packages/flutter/lib/src/painting/gradient.dart
+++ b/packages/flutter/lib/src/painting/gradient.dart
@@ -438,14 +438,14 @@ class LinearGradient extends Gradient {
   @override
   Gradient lerpFrom(Gradient a, double t) {
     if (a == null || (a is LinearGradient))
-      return LinearGradient.lerp(a, this, t);
+      return LinearGradient.lerp(a as LinearGradient, this, t);
     return super.lerpFrom(a, t);
   }
 
   @override
   Gradient lerpTo(Gradient b, double t) {
     if (b == null || (b is LinearGradient))
-      return LinearGradient.lerp(this, b, t);
+      return LinearGradient.lerp(this, b as LinearGradient, t);
     return super.lerpTo(b, t);
   }
 
@@ -498,30 +498,12 @@ class LinearGradient extends Gradient {
       return true;
     if (runtimeType != other.runtimeType)
       return false;
-    final LinearGradient typedOther = other;
-    if (begin != typedOther.begin ||
-        end != typedOther.end ||
-        tileMode != typedOther.tileMode ||
-        colors?.length != typedOther.colors?.length ||
-        stops?.length != typedOther.stops?.length)
-      return false;
-    if (colors != null) {
-      assert(typedOther.colors != null);
-      assert(colors.length == typedOther.colors.length);
-      for (int i = 0; i < colors.length; i += 1) {
-        if (colors[i] != typedOther.colors[i])
-          return false;
-      }
-    }
-    if (stops != null) {
-      assert(typedOther.stops != null);
-      assert(stops.length == typedOther.stops.length);
-      for (int i = 0; i < stops.length; i += 1) {
-        if (stops[i] != typedOther.stops[i])
-          return false;
-      }
-    }
-    return true;
+    return other is LinearGradient
+        && other.begin == begin
+        && other.end == end
+        && other.tileMode == tileMode
+        && listEquals<Color>(other.colors, colors)
+        && listEquals<double>(other.stops, stops);
   }
 
   @override
@@ -714,14 +696,14 @@ class RadialGradient extends Gradient {
   @override
   Gradient lerpFrom(Gradient a, double t) {
     if (a == null || (a is RadialGradient))
-      return RadialGradient.lerp(a, this, t);
+      return RadialGradient.lerp(a as RadialGradient, this, t);
     return super.lerpFrom(a, t);
   }
 
   @override
   Gradient lerpTo(Gradient b, double t) {
     if (b == null || (b is RadialGradient))
-      return RadialGradient.lerp(this, b, t);
+      return RadialGradient.lerp(this, b as RadialGradient, t);
     return super.lerpTo(b, t);
   }
 
@@ -776,32 +758,14 @@ class RadialGradient extends Gradient {
       return true;
     if (runtimeType != other.runtimeType)
       return false;
-    final RadialGradient typedOther = other;
-    if (center != typedOther.center ||
-        radius != typedOther.radius ||
-        tileMode != typedOther.tileMode ||
-        colors?.length != typedOther.colors?.length ||
-        stops?.length != typedOther.stops?.length ||
-        focal != typedOther.focal ||
-        focalRadius != typedOther.focalRadius)
-      return false;
-    if (colors != null) {
-      assert(typedOther.colors != null);
-      assert(colors.length == typedOther.colors.length);
-      for (int i = 0; i < colors.length; i += 1) {
-        if (colors[i] != typedOther.colors[i])
-          return false;
-      }
-    }
-    if (stops != null) {
-      assert(typedOther.stops != null);
-      assert(stops.length == typedOther.stops.length);
-      for (int i = 0; i < stops.length; i += 1) {
-        if (stops[i] != typedOther.stops[i])
-          return false;
-      }
-    }
-    return true;
+    return other is RadialGradient
+        && other.center == center
+        && other.radius == radius
+        && other.tileMode == tileMode
+        && listEquals<Color>(other.colors, colors)
+        && listEquals<double>(other.stops, stops)
+        && other.focal == focal
+        && other.focalRadius == focalRadius;
   }
 
   @override
@@ -980,14 +944,14 @@ class SweepGradient extends Gradient {
   @override
   Gradient lerpFrom(Gradient a, double t) {
     if (a == null || (a is SweepGradient))
-      return SweepGradient.lerp(a, this, t);
+      return SweepGradient.lerp(a as SweepGradient, this, t);
     return super.lerpFrom(a, t);
   }
 
   @override
   Gradient lerpTo(Gradient b, double t) {
     if (b == null || (b is SweepGradient))
-      return SweepGradient.lerp(this, b, t);
+      return SweepGradient.lerp(this, b as SweepGradient, t);
     return super.lerpTo(b, t);
   }
 
@@ -1040,31 +1004,13 @@ class SweepGradient extends Gradient {
       return true;
     if (runtimeType != other.runtimeType)
       return false;
-    final SweepGradient typedOther = other;
-    if (center != typedOther.center ||
-        startAngle != typedOther.startAngle ||
-        endAngle != typedOther.endAngle ||
-        tileMode != typedOther.tileMode ||
-        colors?.length != typedOther.colors?.length ||
-        stops?.length != typedOther.stops?.length)
-      return false;
-    if (colors != null) {
-      assert(typedOther.colors != null);
-      assert(colors.length == typedOther.colors.length);
-      for (int i = 0; i < colors.length; i += 1) {
-        if (colors[i] != typedOther.colors[i])
-          return false;
-      }
-    }
-    if (stops != null) {
-      assert(typedOther.stops != null);
-      assert(stops.length == typedOther.stops.length);
-      for (int i = 0; i < stops.length; i += 1) {
-        if (stops[i] != typedOther.stops[i])
-          return false;
-      }
-    }
-    return true;
+    return other is SweepGradient
+        && other.center == center
+        && other.startAngle == startAngle
+        && other.endAngle == endAngle
+        && other.tileMode == tileMode
+        && listEquals<Color>(other.colors, colors)
+        && listEquals<double>(other.stops, stops);
   }
 
   @override
diff --git a/packages/flutter/lib/src/painting/image_provider.dart b/packages/flutter/lib/src/painting/image_provider.dart
index cc075db566..34205070b1 100644
--- a/packages/flutter/lib/src/painting/image_provider.dart
+++ b/packages/flutter/lib/src/painting/image_provider.dart
@@ -51,7 +51,7 @@ class ImageConfiguration {
     Locale locale,
     TextDirection textDirection,
     Size size,
-    String platform,
+    TargetPlatform platform,
   }) {
     return ImageConfiguration(
       bundle: bundle ?? this.bundle,
@@ -94,13 +94,13 @@ class ImageConfiguration {
   bool operator ==(dynamic other) {
     if (other.runtimeType != runtimeType)
       return false;
-    final ImageConfiguration typedOther = other;
-    return typedOther.bundle == bundle
-        && typedOther.devicePixelRatio == devicePixelRatio
-        && typedOther.locale == locale
-        && typedOther.textDirection == textDirection
-        && typedOther.size == size
-        && typedOther.platform == platform;
+    return other is ImageConfiguration
+        && other.bundle == bundle
+        && other.devicePixelRatio == devicePixelRatio
+        && other.locale == locale
+        && other.textDirection == textDirection
+        && other.size == size
+        && other.platform == platform;
   }
 
   @override
@@ -439,10 +439,10 @@ class AssetBundleImageKey {
   bool operator ==(dynamic other) {
     if (other.runtimeType != runtimeType)
       return false;
-    final AssetBundleImageKey typedOther = other;
-    return bundle == typedOther.bundle
-        && name == typedOther.name
-        && scale == typedOther.scale;
+    return other is AssetBundleImageKey
+        && other.bundle == bundle
+        && other.name == name
+        && other.scale == scale;
   }
 
   @override
@@ -501,10 +501,10 @@ class _SizeAwareCacheKey {
   bool operator ==(Object other) {
     if (other.runtimeType != runtimeType)
       return false;
-    final _SizeAwareCacheKey typedOther = other;
-    return providerCacheKey == typedOther.providerCacheKey
-        && width == typedOther.width
-        && height == typedOther.height;
+    return other is _SizeAwareCacheKey
+        && other.providerCacheKey == providerCacheKey
+        && other.width == width
+        && other.height == height;
   }
 
   @override
@@ -657,9 +657,9 @@ class FileImage extends ImageProvider<FileImage> {
   bool operator ==(dynamic other) {
     if (other.runtimeType != runtimeType)
       return false;
-    final FileImage typedOther = other;
-    return file?.path == typedOther.file?.path
-        && scale == typedOther.scale;
+    return other is FileImage
+        && other.file?.path == file?.path
+        && other.scale == scale;
   }
 
   @override
@@ -718,9 +718,9 @@ class MemoryImage extends ImageProvider<MemoryImage> {
   bool operator ==(dynamic other) {
     if (other.runtimeType != runtimeType)
       return false;
-    final MemoryImage typedOther = other;
-    return bytes == typedOther.bytes
-        && scale == typedOther.scale;
+    return other is MemoryImage
+        && other.bytes == bytes
+        && other.scale == scale;
   }
 
   @override
@@ -855,10 +855,10 @@ class ExactAssetImage extends AssetBundleImageProvider {
   bool operator ==(dynamic other) {
     if (other.runtimeType != runtimeType)
       return false;
-    final ExactAssetImage typedOther = other;
-    return keyName == typedOther.keyName
-        && scale == typedOther.scale
-        && bundle == typedOther.bundle;
+    return other is ExactAssetImage
+        && other.keyName == keyName
+        && other.scale == scale
+        && other.bundle == bundle;
   }
 
   @override
diff --git a/packages/flutter/lib/src/painting/image_resolution.dart b/packages/flutter/lib/src/painting/image_resolution.dart
index bea456e712..fcc0bd7179 100644
--- a/packages/flutter/lib/src/painting/image_resolution.dart
+++ b/packages/flutter/lib/src/painting/image_resolution.dart
@@ -219,11 +219,11 @@ class AssetImage extends AssetBundleImageProvider {
     if (jsonData == null)
       return SynchronousFuture<Map<String, List<String>>>(null);
     // TODO(ianh): JSON decoding really shouldn't be on the main thread.
-    final Map<String, dynamic> parsedJson = json.decode(jsonData);
+    final Map<String, dynamic> parsedJson = json.decode(jsonData) as Map<String, dynamic>;
     final Iterable<String> keys = parsedJson.keys;
     final Map<String, List<String>> parsedManifest =
         Map<String, List<String>>.fromIterables(keys,
-          keys.map<List<String>>((String key) => List<String>.from(parsedJson[key])));
+          keys.map<List<String>>((String key) => List<String>.from(parsedJson[key] as List<dynamic>)));
     // TODO(ianh): convert that data structure to the right types.
     return SynchronousFuture<Map<String, List<String>>>(parsedManifest);
   }
@@ -280,9 +280,9 @@ class AssetImage extends AssetBundleImageProvider {
   bool operator ==(dynamic other) {
     if (other.runtimeType != runtimeType)
       return false;
-    final AssetImage typedOther = other;
-    return keyName == typedOther.keyName
-        && bundle == typedOther.bundle;
+    return other is AssetImage
+        && other.keyName == keyName
+        && other.bundle == bundle;
   }
 
   @override
diff --git a/packages/flutter/lib/src/painting/image_stream.dart b/packages/flutter/lib/src/painting/image_stream.dart
index 0f034ddf28..82e62a773d 100644
--- a/packages/flutter/lib/src/painting/image_stream.dart
+++ b/packages/flutter/lib/src/painting/image_stream.dart
@@ -50,9 +50,9 @@ class ImageInfo {
   bool operator ==(Object other) {
     if (other.runtimeType != runtimeType)
       return false;
-    final ImageInfo typedOther = other;
-    return typedOther.image == image
-        && typedOther.scale == scale;
+    return other is ImageInfo
+        && other.image == image
+        && other.scale == scale;
   }
 }
 
@@ -119,10 +119,10 @@ class ImageStreamListener {
   bool operator ==(dynamic other) {
     if (other.runtimeType != runtimeType)
       return false;
-    final ImageStreamListener typedOther = other;
-    return onImage == typedOther.onImage
-        && onChunk == typedOther.onChunk
-        && onError == typedOther.onError;
+    return other is ImageStreamListener
+        && other.onImage == onImage
+        && other.onChunk == onChunk
+        && other.onError == onError;
   }
 }
 
diff --git a/packages/flutter/lib/src/painting/inline_span.dart b/packages/flutter/lib/src/painting/inline_span.dart
index b31b29349f..4278488d96 100644
--- a/packages/flutter/lib/src/painting/inline_span.dart
+++ b/packages/flutter/lib/src/painting/inline_span.dart
@@ -358,8 +358,8 @@ abstract class InlineSpan extends DiagnosticableTree {
       return true;
     if (other.runtimeType != runtimeType)
       return false;
-    final InlineSpan typedOther = other;
-    return typedOther.style == style;
+    return other is InlineSpan
+        && other.style == style;
   }
 
   @override
diff --git a/packages/flutter/lib/src/painting/matrix_utils.dart b/packages/flutter/lib/src/painting/matrix_utils.dart
index 247aaf5ec1..7f781f23a1 100644
--- a/packages/flutter/lib/src/painting/matrix_utils.dart
+++ b/packages/flutter/lib/src/painting/matrix_utils.dart
@@ -507,11 +507,11 @@ class MatrixUtils {
 
     // Model matrix by first translating the object from the origin of the world
     // by radius in the z axis and then rotating against the world.
-    result *= (
+    result = result * ((
         orientation == Axis.horizontal
             ? Matrix4.rotationY(angle)
             : Matrix4.rotationX(angle)
-    ) * Matrix4.translationValues(0.0, 0.0, radius);
+    ) * Matrix4.translationValues(0.0, 0.0, radius)) as Matrix4;
 
     // Essentially perspective * view * model.
     return result;
diff --git a/packages/flutter/lib/src/painting/rounded_rectangle_border.dart b/packages/flutter/lib/src/painting/rounded_rectangle_border.dart
index afd21d4ae7..fcd388ac94 100644
--- a/packages/flutter/lib/src/painting/rounded_rectangle_border.dart
+++ b/packages/flutter/lib/src/painting/rounded_rectangle_border.dart
@@ -126,9 +126,9 @@ class RoundedRectangleBorder extends ShapeBorder {
   bool operator ==(dynamic other) {
     if (runtimeType != other.runtimeType)
       return false;
-    final RoundedRectangleBorder typedOther = other;
-    return side == typedOther.side
-        && borderRadius == typedOther.borderRadius;
+    return other is RoundedRectangleBorder
+        && other.side == side
+        && other.borderRadius == borderRadius;
   }
 
   @override
@@ -286,10 +286,10 @@ class _RoundedRectangleToCircleBorder extends ShapeBorder {
   bool operator ==(dynamic other) {
     if (runtimeType != other.runtimeType)
       return false;
-    final _RoundedRectangleToCircleBorder typedOther = other;
-    return side == typedOther.side
-        && borderRadius == typedOther.borderRadius
-        && circleness == typedOther.circleness;
+    return other is _RoundedRectangleToCircleBorder
+        && other.side == side
+        && other.borderRadius == borderRadius
+        && other.circleness == circleness;
   }
 
   @override
diff --git a/packages/flutter/lib/src/painting/shape_decoration.dart b/packages/flutter/lib/src/painting/shape_decoration.dart
index 50ae38f452..06cfd2e05f 100644
--- a/packages/flutter/lib/src/painting/shape_decoration.dart
+++ b/packages/flutter/lib/src/painting/shape_decoration.dart
@@ -193,9 +193,9 @@ class ShapeDecoration extends Decoration {
     if (a is BoxDecoration) {
       return ShapeDecoration.lerp(ShapeDecoration.fromBoxDecoration(a), this, t);
     } else if (a == null || a is ShapeDecoration) {
-      return ShapeDecoration.lerp(a, this, t);
+      return ShapeDecoration.lerp(a as ShapeDecoration, this, t);
     }
-    return super.lerpFrom(a, t);
+    return super.lerpFrom(a, t) as ShapeDecoration;
   }
 
   @override
@@ -203,9 +203,9 @@ class ShapeDecoration extends Decoration {
     if (b is BoxDecoration) {
       return ShapeDecoration.lerp(this, ShapeDecoration.fromBoxDecoration(b), t);
     } else if (b == null || b is ShapeDecoration) {
-      return ShapeDecoration.lerp(this, b, t);
+      return ShapeDecoration.lerp(this, b as ShapeDecoration, t);
     }
-    return super.lerpTo(b, t);
+    return super.lerpTo(b, t) as ShapeDecoration;
   }
 
   /// Linearly interpolate between two shapes.
@@ -251,12 +251,12 @@ class ShapeDecoration extends Decoration {
       return true;
     if (runtimeType != other.runtimeType)
       return false;
-    final ShapeDecoration typedOther = other;
-    return color == typedOther.color
-        && gradient == typedOther.gradient
-        && image == typedOther.image
-        && shadows == typedOther.shadows
-        && shape == typedOther.shape;
+    return other is ShapeDecoration
+        && other.color == color
+        && other.gradient == gradient
+        && other.image == image
+        && other.shadows == shadows
+        && other.shape == shape;
   }
 
   @override
diff --git a/packages/flutter/lib/src/painting/stadium_border.dart b/packages/flutter/lib/src/painting/stadium_border.dart
index ce8f4c7322..77b69d38fa 100644
--- a/packages/flutter/lib/src/painting/stadium_border.dart
+++ b/packages/flutter/lib/src/painting/stadium_border.dart
@@ -53,7 +53,7 @@ class StadiumBorder extends ShapeBorder {
     if (a is RoundedRectangleBorder) {
       return _StadiumToRoundedRectangleBorder(
         side: BorderSide.lerp(a.side, side, t),
-        borderRadius: a.borderRadius,
+        borderRadius: a.borderRadius as BorderRadius,
         rectness: 1.0 - t,
       );
     }
@@ -74,7 +74,7 @@ class StadiumBorder extends ShapeBorder {
     if (b is RoundedRectangleBorder) {
       return _StadiumToRoundedRectangleBorder(
         side: BorderSide.lerp(side, b.side, t),
-        borderRadius: b.borderRadius,
+        borderRadius: b.borderRadius as BorderRadius,
         rectness: t,
       );
     }
@@ -113,8 +113,8 @@ class StadiumBorder extends ShapeBorder {
   bool operator ==(dynamic other) {
     if (runtimeType != other.runtimeType)
       return false;
-    final StadiumBorder typedOther = other;
-    return side == typedOther.side;
+    return other is StadiumBorder
+        && other.side == side;
   }
 
   @override
@@ -260,9 +260,9 @@ class _StadiumToCircleBorder extends ShapeBorder {
   bool operator ==(dynamic other) {
     if (runtimeType != other.runtimeType)
       return false;
-    final _StadiumToCircleBorder typedOther = other;
-    return side == typedOther.side
-        && circleness == typedOther.circleness;
+    return other is _StadiumToCircleBorder
+        && other.side == side
+        && other.circleness == circleness;
   }
 
   @override
@@ -402,10 +402,10 @@ class _StadiumToRoundedRectangleBorder extends ShapeBorder {
   bool operator ==(dynamic other) {
     if (runtimeType != other.runtimeType)
       return false;
-    final _StadiumToRoundedRectangleBorder typedOther = other;
-    return side == typedOther.side
-        && borderRadius == typedOther.borderRadius
-        && rectness == typedOther.rectness;
+    return other is _StadiumToRoundedRectangleBorder
+        && other.side == side
+        && other.borderRadius == borderRadius
+        && other.rectness == rectness;
   }
 
   @override
diff --git a/packages/flutter/lib/src/painting/strut_style.dart b/packages/flutter/lib/src/painting/strut_style.dart
index 3cd4f57984..fa163dc444 100644
--- a/packages/flutter/lib/src/painting/strut_style.dart
+++ b/packages/flutter/lib/src/painting/strut_style.dart
@@ -546,14 +546,14 @@ class StrutStyle extends Diagnosticable {
       return true;
     if (other.runtimeType != runtimeType)
       return false;
-    final StrutStyle typedOther = other;
-    return fontFamily == typedOther.fontFamily &&
-           fontSize == typedOther.fontSize &&
-           fontWeight == typedOther.fontWeight &&
-           fontStyle == typedOther.fontStyle &&
-           height == typedOther.height &&
-           leading == typedOther.leading &&
-           forceStrutHeight == typedOther.forceStrutHeight;
+    return other is StrutStyle
+        && other.fontFamily == fontFamily
+        && other.fontSize == fontSize
+        && other.fontWeight == fontWeight
+        && other.fontStyle == fontStyle
+        && other.height == height
+        && other.leading == leading
+        && other.forceStrutHeight == forceStrutHeight;
   }
 
   @override
diff --git a/packages/flutter/lib/src/painting/text_painter.dart b/packages/flutter/lib/src/painting/text_painter.dart
index 24a70d45e2..2fd8a8d2fa 100644
--- a/packages/flutter/lib/src/painting/text_painter.dart
+++ b/packages/flutter/lib/src/painting/text_painter.dart
@@ -549,7 +549,7 @@ class TextPainter {
     _lastMaxWidth = maxWidth;
     _paragraph.layout(ui.ParagraphConstraints(width: maxWidth));
     if (minWidth != maxWidth) {
-      final double newWidth = maxIntrinsicWidth.clamp(minWidth, maxWidth);
+      final double newWidth = maxIntrinsicWidth.clamp(minWidth, maxWidth) as double;
       if (newWidth != width) {
         _paragraph.layout(ui.ParagraphConstraints(width: newWidth));
       }
diff --git a/packages/flutter/lib/src/painting/text_span.dart b/packages/flutter/lib/src/painting/text_span.dart
index 433fd65c6f..93d49d02a0 100644
--- a/packages/flutter/lib/src/painting/text_span.dart
+++ b/packages/flutter/lib/src/painting/text_span.dart
@@ -261,7 +261,7 @@ class TextSpan extends InlineSpan {
           child is TextSpan,
           'visitTextSpan is deprecated. Use visitChildren to support InlineSpans',
         );
-        final TextSpan textSpanChild = child;
+        final TextSpan textSpanChild = child as TextSpan;
         if (!textSpanChild.visitTextSpan(visitor))
           return false;
       }
@@ -388,7 +388,7 @@ class TextSpan extends InlineSpan {
       return RenderComparison.identical;
     if (other.runtimeType != runtimeType)
       return RenderComparison.layout;
-    final TextSpan textSpan = other;
+    final TextSpan textSpan = other as TextSpan;
     if (textSpan.text != text ||
         children?.length != textSpan.children?.length ||
         (style == null) != (textSpan.style == null))
@@ -423,11 +423,11 @@ class TextSpan extends InlineSpan {
       return false;
     if (super != other)
       return false;
-    final TextSpan typedOther = other;
-    return typedOther.text == text
-        && typedOther.recognizer == recognizer
-        && typedOther.semanticsLabel == semanticsLabel
-        && listEquals<InlineSpan>(typedOther.children, children);
+    return other is TextSpan
+        && other.text == text
+        && other.recognizer == recognizer
+        && other.semanticsLabel == semanticsLabel
+        && listEquals<InlineSpan>(other.children, children);
   }
 
   @override
diff --git a/packages/flutter/lib/src/painting/text_style.dart b/packages/flutter/lib/src/painting/text_style.dart
index 939e4797b3..3e9bc2cd4a 100644
--- a/packages/flutter/lib/src/painting/text_style.dart
+++ b/packages/flutter/lib/src/painting/text_style.dart
@@ -833,7 +833,7 @@ class TextStyle extends Diagnosticable {
       fontFamily: fontFamily ?? this.fontFamily,
       fontFamilyFallback: fontFamilyFallback ?? this.fontFamilyFallback,
       fontSize: fontSize == null ? null : fontSize * fontSizeFactor + fontSizeDelta,
-      fontWeight: fontWeight == null ? null : FontWeight.values[(fontWeight.index + fontWeightDelta).clamp(0, FontWeight.values.length - 1)],
+      fontWeight: fontWeight == null ? null : FontWeight.values[(fontWeight.index + fontWeightDelta).clamp(0, FontWeight.values.length - 1) as int],
       fontStyle: fontStyle,
       letterSpacing: letterSpacing == null ? null : letterSpacing * letterSpacingFactor + letterSpacingDelta,
       wordSpacing: wordSpacing == null ? null : wordSpacing * wordSpacingFactor + wordSpacingDelta,
@@ -1144,28 +1144,28 @@ class TextStyle extends Diagnosticable {
       return true;
     if (other.runtimeType != runtimeType)
       return false;
-    final TextStyle typedOther = other;
-    return inherit == typedOther.inherit &&
-           color == typedOther.color &&
-           backgroundColor == typedOther.backgroundColor &&
-           fontFamily == typedOther.fontFamily &&
-           fontSize == typedOther.fontSize &&
-           fontWeight == typedOther.fontWeight &&
-           fontStyle == typedOther.fontStyle &&
-           letterSpacing == typedOther.letterSpacing &&
-           wordSpacing == typedOther.wordSpacing &&
-           textBaseline == typedOther.textBaseline &&
-           height == typedOther.height &&
-           locale == typedOther.locale &&
-           foreground == typedOther.foreground &&
-           background == typedOther.background &&
-           decoration == typedOther.decoration &&
-           decorationColor == typedOther.decorationColor &&
-           decorationStyle == typedOther.decorationStyle &&
-           decorationThickness == typedOther.decorationThickness &&
-           listEquals(shadows, typedOther.shadows) &&
-           listEquals(fontFeatures, typedOther.fontFeatures) &&
-           listEquals(fontFamilyFallback, typedOther.fontFamilyFallback);
+    return other is TextStyle
+        && other.inherit == inherit
+        && other.color == color
+        && other.backgroundColor == backgroundColor
+        && other.fontFamily == fontFamily
+        && other.fontSize == fontSize
+        && other.fontWeight == fontWeight
+        && other.fontStyle == fontStyle
+        && other.letterSpacing == letterSpacing
+        && other.wordSpacing == wordSpacing
+        && other.textBaseline == textBaseline
+        && other.height == height
+        && other.locale == locale
+        && other.foreground == foreground
+        && other.background == background
+        && other.decoration == decoration
+        && other.decorationColor == decorationColor
+        && other.decorationStyle == decorationStyle
+        && other.decorationThickness == decorationThickness
+        && listEquals(other.shadows, shadows)
+        && listEquals(other.fontFeatures, fontFeatures)
+        && listEquals(other.fontFamilyFallback, fontFamilyFallback);
   }
 
   @override