Uniform rectangular borders were drawing in the wrong place. (#12179)

I inflated instead of deflating. Oops.

packages/flutter/lib/src/painting/border.dart

@@ -398,7 +398,7 @@ class Border {
       ..color = top.color
       ..strokeWidth = width
       ..style = PaintingStyle.stroke;
-    canvas.drawRect(rect.inflate(width / 2.0), paint);
+    canvas.drawRect(rect.deflate(width / 2.0), paint);
   }
 
   @override

packages/flutter/test/rendering/mock_canvas.dart

@@ -176,6 +176,24 @@ abstract class PaintPattern {
   /// arguments as they were seen by the method.
   void rrect({ RRect rrect, Color color, double strokeWidth, bool hasMaskFilter, PaintingStyle style });
 
+  /// Indicates that a rounded rectangle outline is expected next.
+  ///
+  /// The next call to [Canvas.drawRRect] is examined. Any arguments that are
+  /// passed to this method are compared to the actual [Canvas.drawRRect] call's
+  /// arguments and any mismatches result in failure.
+  ///
+  /// If no call to [Canvas.drawRRect] was made, then this results in failure.
+  ///
+  /// Any calls made between the last matched call (if any) and the
+  /// [Canvas.drawRRect] call are ignored.
+  ///
+  /// The [Paint]-related arguments (`color`, `strokeWidth`, `hasMaskFilter`,
+  /// `style`) are compared against the state of the [Paint] object after the
+  /// painting has completed, not at the time of the call. If the same [Paint]
+  /// object is reused multiple times, then this may not match the actual
+  /// arguments as they were seen by the method.
+  void drrect({ RRect outer, RRect inner, Color color, double strokeWidth, bool hasMaskFilter, PaintingStyle style });
+
   /// Indicates that a circle is expected next.
   ///
   /// The next circle is examined. Any arguments that are passed to this method
@@ -424,6 +442,11 @@ class _TestRecordingCanvasPatternMatcher extends _TestRecordingCanvasMatcher imp
     _predicates.add(new _RRectPaintPredicate(rrect: rrect, color: color, strokeWidth: strokeWidth, hasMaskFilter: hasMaskFilter, style: style));
   }
 
+  @override
+  void drrect({ RRect outer, RRect inner, Color color, double strokeWidth, bool hasMaskFilter, PaintingStyle style }) {
+    _predicates.add(new _DRRectPaintPredicate(outer: outer, inner: inner, color: color, strokeWidth: strokeWidth, hasMaskFilter: hasMaskFilter, style: style));
+  }
+
   @override
   void circle({ double x, double y, double radius, Color color, double strokeWidth, bool hasMaskFilter, PaintingStyle style }) {
     _predicates.add(new _CirclePaintPredicate(x: x, y: y, radius: radius, color: color, strokeWidth: strokeWidth, hasMaskFilter: hasMaskFilter, style: style));
@@ -631,6 +654,51 @@ class _OneParameterPaintPredicate<T> extends _DrawCommandPaintPredicate {
   }
 }
 
+class _TwoParameterPaintPredicate<T1, T2> extends _DrawCommandPaintPredicate {
+  _TwoParameterPaintPredicate(Symbol symbol, String name, {
+    @required this.expected1,
+    @required this.expected2,
+    @required Color color,
+    @required double strokeWidth,
+    @required bool hasMaskFilter,
+    @required PaintingStyle style
+  }) : super(
+    symbol, name, 3, 2, color: color, strokeWidth: strokeWidth, hasMaskFilter: hasMaskFilter, style: style);
+
+  final T1 expected1;
+
+  final T2 expected2;
+
+  @override
+  void verifyArguments(List<dynamic> arguments) {
+    super.verifyArguments(arguments);
+    final T1 actual1 = arguments[0];
+    if (expected1 != null && actual1 != expected1)
+      throw 'It called $methodName with its first argument (a $T1), $actual1, which was not exactly the expected $T1 ($expected1).';
+    final T2 actual2 = arguments[1];
+    if (expected2 != null && actual2 != expected2)
+      throw 'It called $methodName with its second argument (a $T2), $actual2, which was not exactly the expected $T2 ($expected2).';
+  }
+
+  @override
+  void debugFillDescription(List<String> description) {
+    super.debugFillDescription(description);
+    if (expected1 != null) {
+      if (expected1.toString().contains(T1.toString())) {
+        description.add('$expected1');
+      } else {
+        description.add('$T1: $expected1');
+      }
+    }
+    if (expected2 != null) {
+      if (expected2.toString().contains(T2.toString())) {
+        description.add('$expected2');
+      } else {
+        description.add('$T2: $expected2');
+      }
+    }
+  }
+}
 
 class _RectPaintPredicate extends _OneParameterPaintPredicate<Rect> {
   _RectPaintPredicate({ Rect rect, Color color, double strokeWidth, bool hasMaskFilter, PaintingStyle style }) : super(
@@ -656,6 +724,19 @@ class _RRectPaintPredicate extends _OneParameterPaintPredicate<RRect> {
   );
 }
 
+class _DRRectPaintPredicate extends _TwoParameterPaintPredicate<RRect, RRect> {
+  _DRRectPaintPredicate({ RRect inner, RRect outer, Color color, double strokeWidth, bool hasMaskFilter, PaintingStyle style }) : super(
+    #drawDRRect,
+    'a rounded rectangle outline',
+    expected1: outer,
+    expected2: inner,
+    color: color,
+    strokeWidth: strokeWidth,
+    hasMaskFilter: hasMaskFilter,
+    style: style,
+  );
+}
+
 class _CirclePaintPredicate extends _DrawCommandPaintPredicate {
   _CirclePaintPredicate({ this.x, this.y, this.radius, Color color, double strokeWidth, bool hasMaskFilter, PaintingStyle style }) : super(
     #drawCircle, 'a circle', 3, 2, color: color, strokeWidth: strokeWidth, hasMaskFilter: hasMaskFilter, style: style

packages/flutter/test/widgets/box_decoration_test.dart

@@ -89,6 +89,99 @@ void main() {
       ..path()); // all appear to have the same settings here (that of the last call).
   });
 
+  testWidgets('BoxDecoration paints its border correctly', (WidgetTester tester) async {
+    // Regression test for https://github.com/flutter/flutter/issues/12165
+    await tester.pumpWidget(
+      new Column(
+        children: <Widget>[
+          new Container(
+            // There's not currently a way to verify that this paints the same size as the others,
+            // so the pattern below just asserts that there's four paths but doesn't check the geometry.
+            width: 100.0,
+            height: 100.0,
+            decoration: const BoxDecoration(
+              border: const Border(
+                top: const BorderSide(
+                  width: 10.0,
+                  color: const Color(0xFFEEEEEE),
+                ),
+                left: const BorderSide(
+                  width: 10.0,
+                  color: const Color(0xFFFFFFFF),
+                ),
+                right: const BorderSide(
+                  width: 10.0,
+                  color: const Color(0xFFFFFFFF),
+                ),
+                bottom: const BorderSide(
+                  width: 10.0,
+                  color: const Color(0xFFFFFFFF),
+                ),
+              ),
+            ),
+          ),
+          new Container(
+            width: 100.0,
+            height: 100.0,
+            decoration: new BoxDecoration(
+              border: new Border.all(
+                width: 10.0,
+                color: const Color(0xFFFFFFFF),
+              ),
+            ),
+          ),
+          new Container(
+            width: 100.0,
+            height: 100.0,
+            decoration: new BoxDecoration(
+              border: new Border.all(
+                width: 10.0,
+                color: const Color(0xFFFFFFFF),
+              ),
+              borderRadius: const BorderRadius.only(
+                topRight: const Radius.circular(10.0),
+              ),
+            ),
+          ),
+          new Container(
+            width: 100.0,
+            height: 100.0,
+            decoration: new BoxDecoration(
+              border: new Border.all(
+                width: 10.0,
+                color: const Color(0xFFFFFFFF),
+              ),
+              shape: BoxShape.circle,
+            ),
+          ),
+        ],
+      ),
+    );
+    expect(find.byType(Column), paints
+      ..path()
+      ..path()
+      ..path()
+      ..path()
+      ..rect(rect: new Rect.fromLTRB(355.0, 105.0, 445.0, 195.0))
+      ..drrect(
+        outer: new RRect.fromLTRBAndCorners(
+          350.0, 200.0, 450.0, 300.0,
+          topLeft: Radius.zero,
+          topRight: const Radius.circular(10.0),
+          bottomRight: Radius.zero,
+          bottomLeft: Radius.zero,
+        ),
+        inner: new RRect.fromLTRBAndCorners(
+          360.0, 210.0, 440.0, 290.0,
+          topLeft: const Radius.circular(-10.0),
+          topRight: Radius.zero,
+          bottomRight: const Radius.circular(-10.0),
+          bottomLeft: const Radius.circular(-10.0),
+        ),
+      )
+      ..circle(x: 400.0, y: 350.0, radius: 45.0)
+    );
+  });
 
   testWidgets('Can hit test on BoxDecoration', (WidgetTester tester) async {