avoid-unconditional-break

v1.9.0

warning

recommended

pro+

Warns when a break, continue, return or throw are used unconditionally in a for loop.

Example

❌ Bad:

void main() {
  final list = <int>[];

  for (final item in list) {
    // LINT: Avoid unconditional break statements. This loop is always interrupted after one iteration.
    //  Try removing this statement or call it conditionally.
    continue;
  }

  for (final item in list) {
    // LINT: Avoid unconditional break statements. This loop is always interrupted after one iteration.
    //  Try removing this statement or call it conditionally.
    break;
  }

  for (final item in list) {
    // LINT: Avoid unconditional break statements. This loop is always interrupted after one iteration.
    //  Try removing this statement or call it conditionally.
    return;
  }

  for (final item in list) {
    // LINT: Avoid unconditional break statements. This loop is always interrupted after one iteration.
    //  Try removing this statement or call it conditionally.
    throw '';
  }
}

✅ Good:

void main() {
  final list = <int>[];

  for (final item in list) {
    if (someCondition) { // Correct, only in some cases
      continue;
    }
  }

  for (final item in list) {
    if (someCondition) {
      break;
    }
  }

  for (final item in list) {
    if (someCondition) {
      return;
    }
  }

  for (final item in list) {
    if (someCondition) {
      throw '';
    }
  }
}

Additional Resources

• CWE-670: Always-Incorrect Control Flow Implementation