ADD: Tests for the squircle shapes from orig rejected PR

test/squircle_border_test.dart

@@ -0,0 +1,150 @@
+// Copyright 2019 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.
+
+// These are the original test for the rejected PR.
+// Only updated to use borderRadius and null safety version. The tests needs
+// to be reviewed and revised, but they are a good starting point.
+
+import 'dart:io' show Platform;
+
+import 'package:flutter/material.dart';
+import 'package:flutter_test/flutter_test.dart';
+import 'package:squircle_study/squircle/squircle_border.dart';
+
+void main() {
+  test('Continuous rectangle border scale and lerp', () {
+    const SquircleBorder c10 =
+        SquircleBorder(borderRadius: BorderRadius.all(Radius.circular(100)));
+    const SquircleBorder c15 =
+        SquircleBorder(borderRadius: BorderRadius.all(Radius.circular(150)));
+    const SquircleBorder c20 =
+        SquircleBorder(borderRadius: BorderRadius.all(Radius.circular(200)));
+    expect(c10.dimensions, EdgeInsets.zero);
+    expect(c10.scale(2.0), c20);
+    expect(c20.scale(0.5), c10);
+    expect(ShapeBorder.lerp(c10, c20, 0.0), c10);
+    expect(ShapeBorder.lerp(c10, c20, 0.5), c15);
+    expect(ShapeBorder.lerp(c10, c20, 1.0), c20);
+  });
+
+  testWidgets('Golden test medium sized rectangle, medium radius',
+      (WidgetTester tester) async {
+    await tester.pumpWidget(
+      RepaintBoundary(
+        child: Container(
+          alignment: Alignment.center,
+          child: Material(
+            color: Colors.blueAccent[400],
+            shape: const SquircleBorder(
+              borderRadius: BorderRadius.all(Radius.circular(28)),
+            ),
+            child: const SizedBox(
+              height: 100,
+              width: 100,
+            ),
+          ),
+        ),
+      ),
+    );
+
+    await tester.pumpAndSettle();
+
+    await expectLater(
+      find.byType(RepaintBoundary),
+      matchesGoldenFile(
+          'continuous_rectangle_border.golden_test_medium_medium.png'),
+      skip: !Platform.isLinux,
+    );
+  });
+
+  testWidgets('Golden test small sized rectangle, medium radius',
+      (WidgetTester tester) async {
+    await tester.pumpWidget(
+      RepaintBoundary(
+        child: Container(
+          alignment: Alignment.center,
+          child: Material(
+            color: Colors.blueAccent[400],
+            shape: const SquircleBorder(
+              borderRadius: BorderRadius.all(Radius.circular(28)),
+            ),
+            child: const SizedBox(
+              height: 10,
+              width: 100,
+            ),
+          ),
+        ),
+      ),
+    );
+
+    await tester.pumpAndSettle();
+
+    await expectLater(
+      find.byType(RepaintBoundary),
+      matchesGoldenFile(
+          'continuous_rectangle_border.golden_test_small_medium.png'),
+      skip: !Platform.isLinux,
+    );
+  });
+
+  testWidgets('Golden test very small rectangle, medium radius',
+      (WidgetTester tester) async {
+    await tester.pumpWidget(
+      RepaintBoundary(
+        child: Container(
+          alignment: Alignment.center,
+          child: Material(
+            color: Colors.blueAccent[400],
+            shape: const SquircleBorder(
+              borderRadius: BorderRadius.all(Radius.circular(28)),
+            ),
+            child: const SizedBox(
+              height: 5,
+              width: 100,
+            ),
+          ),
+        ),
+      ),
+    );
+
+    await tester.pumpAndSettle();
+
+    await expectLater(
+      find.byType(RepaintBoundary),
+      matchesGoldenFile(
+          'continuous_rectangle_border.golden_test_vsmall_medium.png'),
+      skip: !Platform.isLinux,
+    );
+  });
+
+  testWidgets('Golden test large rectangle, large radius',
+      (WidgetTester tester) async {
+    await tester.pumpWidget(
+      RepaintBoundary(
+        child: Container(
+          alignment: Alignment.center,
+          child: Material(
+            color: Colors.blueAccent[400],
+            shape: const SquircleBorder(
+              borderRadius: BorderRadius.all(Radius.circular(50)),
+            ),
+            child: const SizedBox(
+              height: 300,
+              width: 300,
+            ),
+          ),
+        ),
+      ),
+    );
+
+    await tester.pumpAndSettle();
+
+    await expectLater(
+      find.byType(RepaintBoundary),
+      matchesGoldenFile(
+          'continuous_rectangle_border.golden_test_large_large.png'),
+      skip: !Platform.isLinux,
+    );
+  });
+}