══╡ EXCEPTION CAUGHT BY WIDGETS LIBRARY ╞════════════════════════════
The following assertion was thrown building _InkResponseStateWidget(gestures: [tap], mouseCursor:
ButtonStyleButton_MouseCursor, clipped to BoxShape.rectangle, dirty, state:
_InkResponseState#4b944):
No Directionality widget found.
...
Typically, the Directionality widget is introduced by the MaterialApp or WidgetsApp widget at the
top of your application widget tree. It determines the ambient reading direction and is used, for
example, to determine how to lay out text, how to interpret "start" and "end" values, and to resolve
EdgeInsetsDirectional, AlignmentDirectional, and other *Directional objects.

testWidgets('ボタン名が正しい', (WidgetTester tester) async {
      await tester.pumpWidget(
        MaterialApp(
          home: CButton(child: const Text('button_title')),
        ),
      );
      expect(find.text('button_title'), findsOneWidget);
    });
  });

import 'package:flutter/material.dart';

class TestUtil {
  static Widget setApp(Widget widget) {
    return MaterialApp(home: widget);
  }
}