How to test Flutter widgets on different screen sizes?

Question

I have a Flutter widget which shows extra data depending on the screen size. Does anyone know a way of testing this widget on multiple different screen sizes?

I\'ve

Answer 1

Although @Rémi Rousselet's answer was very helpful it didn't completely solve my problem. It turns out that I could just wrap my widget under test in a MediaQuery widget and set the size.

import 'package:flutter/material.dart';
import 'package:flutter_test/flutter_test.dart';

void main() {
  Widget makeTestableWidget({Widget child, Size size}) {
    return MaterialApp(
      home: MediaQuery(
        data: MediaQueryData(size: size),
        child: child,
      ),
    );
  }

  testWidgets("tablet", (tester) async {
    final testableWidget = makeTestableWidget(
      child: WidgetUnderTest(),
      size: Size(1024, 768),
    );

    ...
  });

  testWidgets("phone", (tester) async {
    final testableWidget = makeTestableWidget(
      child: WidgetUnderTest(),
      size: Size(375, 812),
    );

    ...
  });
}