type_literal_in_constant_pattern

Don’t use constant patterns with type literals.

This rule is available as of Dart 3.0.0.

This rule has a quick fix available.

Details

If you meant to test if the object has type Foo, instead write Foo _.

BAD:

void f(Object? x) {
  if (x case num) {
    print('int or double');
  }
}

GOOD:

void f(Object? x) {
  if (x case num _) {
    print('int or double');
  }
}

If you do mean to test that the matched value (which you expect to have the type Type) is equal to the type literal Foo, then this lint can be silenced using const (Foo).

BAD:

void f(Object? x) {
  if (x case int) {
    print('int');
  }
}

GOOD:

void f(Object? x) {
  if (x case const (int)) {
    print('int');
  }
}

Usage

To enable the type_literal_in_constant_pattern rule, add type_literal_in_constant_pattern under linter > rules in your analysis_options.yaml file:

linter:
  rules:
    - type_literal_in_constant_pattern