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avoid-missed-calls

added in: 1.3.0
warning
🛠
Pro+
preset: recommended

Warns when a method that should be invoked is passed as tear-off.

Missed invocations are usually a sign of a bug and can lead to unexpected results.

Example​

❌ Bad:

String _strHandle() => 'Hi!';

void main() {
  SomeClass(
    // LINT: This identifier is expected to be an invocation. Try adding ().
    callback: () async => _handle,
    // LINT: This identifier is expected to be an invocation. Try adding ().
    regular: () => _handle,
    another: _strHandle,
  );
}

class SomeClass {
  final Future<void> Function() callback;
  final void Function() regular;
  final String Function() another;

  const SomeClass({
    required this.callback,
    required this.regular,
    required this.another,
  });
}

void _handle() {
  ...
}

✅ Good:

void main() {
  SomeClass(
    callback: () async => _handle(), // Correct, invoked
    regular: () => _handle(), // Correct, invoked
    another: _strHandle, // Correct, passed as tear-off
  );
}