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avoid-nullable-tostring

added in: 1.13.0
warning
🛠
Pro+
preset: recommended

Warns when the toString method is called on a nullable value.

Calling toString on a nullable value can result in an unexpected output (e.g. 'null').

Example​

❌ Bad:

void fn(String? nullableValue) {
  // LINT: Avoid calling 'toString' on nullable targets. Try replacing with the null-aware '?.toString'.
  print(nullableValue.toString());
}

✅ Good:

void fn(String? nullableValue) {
  print(nullableValue?.toString());
}

Additional Resources​