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avoid-unnecessary-type-assertions

added in: 1.6.0

Warns about unnecessary usage of is and whereType operators.

Example

Example 1: check is same type

class Example {
final myList = <int>[1, 2, 3];

void main() {
final result = myList is List<int>; // LINT
myList.whereType<int>();
}
}

Example 2: whereType method

main(){
['1', '2'].whereType<String?>(); // LINT
}

Example 3: patterns

class Animal {}

class HomeAnimal extends Animal {}

void main() {
final animal = Animal();

if (animal case HomeAnimal result) {}
if (animal case HomeAnimal()) {}

if (animal case Animal result) {} // LINT
if (animal case Animal()) {} // LINT
}