bug: AssetCache.readJson fails for json files where the root is an array

[projectitis]

Current bug behavior

Reading a JSON file using AssetCache.readJson results in an error if the JSON file root element is an array.

An example JSON file that meets this criteria is

[
    "The root of this JSON file is an array",
    "Which is perfectly legal JSON"
]

The error is

_TypeError (type 'List<dynamic>' is not a subtype of type 'Map<String, dynamic>' in type cast)

This is because it attempts to cast the result to a Map<String, dynamic>, however, a JSON file can also be a List<dynamic>.

Expected behavior

AssetCache.readJson should return a Future<dynamic> (It uses jsonDecode under the hood, which returns dynamic).

Steps to reproduce

1. Include the JSON file above in the assets (and your pubspec)
2. ensure you import 'package:flame/cache.dart';
3. call AssetsCache().readJson('test.json')

More environment information

• Flame version latest
• Affects all platforms

More information

I can provide the fix. It's very simple and I think it will be backwards compatible in most cases?

[spydon]

Sounds good, I'll assign you to the issue

[spydon]

Closing this meanwhile, since it is added to the #1938 list