null_argument_to_non_null_type
'{0}' shouldn't be called with a 'null' argument for the non-nullable type argument '{1}'.
Description
#The analyzer produces this diagnostic when null
is passed to either the constructor Future.value
or the method Completer.complete
when the type argument used to create the instance was non-nullable. Even though the type system can't express this restriction, passing in a null
results in a runtime exception.
Example
#The following code produces this diagnostic because null
is being passed to the constructor Future.value
even though the type argument is the non-nullable type String
:
Future<String> f() {
return Future.value(null);
}
Common fixes
#Pass in a non-null value:
Future<String> f() {
return Future.value('');
}
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