use-then-answer

v1.36.0

warning

effort: 2m

pro+

Warns when thenReturn is used with Future or Stream.

Example

❌ Bad:

void main() {
  // LINT: 'thenReturn' should not be used to return a Stream or Future.
  //  Use 'thenAnswer' instead.
  when(() => expression).thenReturn(Future.value(1));
}

✅ Good:

void main() {
  when(() => expression).thenAnswer(Future.value(1));
  when(() => expression).thenReturn(1);
}