no_duplicate_case_values

Don’t use more than one case with same value.

This rule is available as of Dart 2.0.0.

Rule sets: core, recommended, flutter

This rule has a quick fix available.

Details

DON’T use more than one case with same value.

This is usually a typo or changed value of constant.

BAD:

const int A = 1;
switch (v) {
  case 1:
  case 2:
  case A:
  case 2:
}

GOOD:

const int A = 1;
switch (v) {
  case A:
  case 2:
}

NOTE: this lint only reports duplicate cases in libraries opted in to Dart 2.19 and below. In Dart 3.0 and after, duplicate cases are reported as dead code by the analyzer.

Usage

To enable the no_duplicate_case_values rule, add no_duplicate_case_values under linter > rules in your analysis_options.yaml file:

linter:
  rules:
    - no_duplicate_case_values