prefer_ is_ not_ empty
Use 'isNotEmpty' rather than negating the result of 'isEmpty'.
Description
#
The analyzer produces this diagnostic when the result of invoking
Iterable.isEmpty
or
Map.isEmpty
is negated.
Example
#
The following code produces this diagnostic because the result of invoking
Iterable.isEmpty
is negated:
void f(Iterable<int> p) => !p.isEmpty ? p.first : 0;
Common fixes
#Rewrite the code to use isNotEmpty
:
void f(Iterable<int> p) => p.isNotEmpty ? p.first : 0;
Unless stated otherwise, the documentation on this site reflects Dart 3.9.2. Page last updated on 2025-9-1. View source or report an issue.