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avoid-throw-objects-without-tostring

added in: 1.4.0
warning
Pro+
preset: recommended

Warns when a thrown object does not implement toString.

Objects that do not implement the toString method will be represented as "Instance of ..." when serialized.

Example​

❌ Bad:

void function() {
  try {
    // ...
  } on Object {
    throw MyException(); // LINT: Avoid throwing objects that do not implement the 'toString' method.
  }
}

class MyException {}

✅ Good:

void function() {
  try {
    // ...
  } on Object {
    throw MyException();
  }
}

class MyException {
  @override
  String toString() => ...;
}

Additional Resources​