Why tests passes individually and fail on terminal CLI execution? - flutter

Question

I'm writting tests to ensure a set of initialization rules on an object with an optional parameter, like the one below:
part 'example.g.dart';
#JsonSerializable(createToJson: false)
class Example {
String req1;
String req2;
String? opt;
Example({required this.req1, required this.req2, this.opt});
factory Example.fromJson(Map<String, dynamic> json) =>
_$ExampleFromJson(json);
}
My .g.dart is the following:
Example _$ExampleFromJson(Map<String, dynamic> json) {
return Example(
req1: json['req1'] as String,
req2: json['req2'] as String,
opt: json['opt'] as String?,
);
}
The following two tests passes when executed individually, through android studio GUI, and fail through in flutter test CLI execution.
test('should fail when json without req1 is provided', () {
var testJson = {
'req2': 'a-req2',
};
expect(() => Example.fromJson(testJson), throwsA(isA<TypeError>()));
});
test('should fail when json without req2 is provided', () {
var testJson = {
'req1': 'a-req1',
};
expect(() => Example.fromJson(testJson), throwsA(isA<TypeError>()));
});
Dart version from android studio and terminal are different (2.10 and 2.17.6), but the execution also fails in our CI, which has the same version of GUI, which works.
The error presented when the pipeline executes is the following:
Expected: throws <Instance of 'TypeError'>
Actual: <Closure: () => Example>
Which: returned <Instance of 'Example'>
So the object does get instantiated, even with null value in required fields.
Any idea why?