asset_field_not_list

The value of the 'assets' field is expected to be a list of relative file paths.

The analyzer produces this diagnostic when the value of the assets key isn't a list.

The following code produces this diagnostic because the value of the assets key is a string when a list is expected:

name: example
flutter:
  assets: assets/

Change the value of the asset list so that it's a list:

name: example
flutter:
  assets:
    - assets/