avoid-inferrable-type-arguments

added in: 1.11.0

style

⚙️🛠

Pro+

preset: recommended

Warns when an inferrable type argument can be removed without affecting the code.

This rule mostly covers return statements, method invocations and collection literals.

warning

This rule is not compatible with prefer-explicit-type-arguments.

⚙️ Config

Set ignored-invocations (default is empty) to ignore type arguments of a specific invocation.

dart_code_metrics:
  ...
  rules:
    ...
    - avoid-inferrable-type-arguments:
        ignored-invocations:
          - context.read
          - GetIt.I
          - watch

Example

❌ Bad:

void main() {
  withList(<num>[1]); // LINT

  final List<int>? nullableList = null;
  withList(nullableList ?? <num>[1]); // LINT
  withList(nullableList == null ? <num>[1] : <num>[2]); // LINT

  withGenericList(<String>['1']); // LINT

  withList(withGenericList<num>([1])); // LINT
  withList(onlyParam<String>('1')); // LINT
}

void withList(List<num> items) {}

List<T> withGenericList<T>(List<T> items) => items;

List<num> onlyParam<P>(P param) => [1];

✅ Good:

void main() {
  withList(<int>[1]);
  withList([1]);

  final List<int>? nullableList = null;
  withList(nullableList ?? [1]);
  withList(nullableList == null ? [1] : [2]);

  withGenericList(['1']);

  withList(withGenericList([1]));
  withList(onlyParam('1'));
}

void withList(List<num> items) {}

List<T> withGenericList<T>(List<T> items) => items;

List<num> onlyParam<P>(P param) => [1];