Pattern: Use of default clause
Issue: -
Switches on enums and enum-like classes should not use a default clause.
Enum-like classes are defined as concrete (non-abstract) classes that have:
- only private non-factory constructors
- two or more static const fields whose type is the enclosing class and
- no subclasses of the class in the defining library
DO define default behavior outside switch statements.
Example of correct code:
switch (testEnum) {
case TestEnum.A:
return '123';
case TestEnum.B:
return 'abc';
}
// Default here.
return null;Example of incorrect code:
switch (testEnum) {
case TestEnum.A:
return '123';
case TestEnum.B:
return 'abc';
default:
return null;
}