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avoid-nullable-parameters-with-default-values

added in: 1.10.0
warning
🛠
Pro+
preset: recommended

Warns when a parameter with the default value is marked as nullable.

Parameters with default values can never be null (the default value will be assigned instead) and can be simply converted to non-null.

Example​

❌ Bad:

void fn({int? a = 5}) {} // LINT: This parameter can be safely made non-nullable.

void fn([int? a = 5]) {} // LINT: This parameter can be safely made non-nullable.

✅ Good:

void fn({int? a}) {} // Correct, has no default value

void fn({required int a}) {}

void fn({int a = 5}) {} // Correct, marked non-nullable