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avoid-nested-switch-expressions

added in: 1.5.0
style
⚙️
Dart 3.0+
Pro+

Warns when a switch expression contains another switch expression.

Multiple nested switch expressions can significantly reduce readability.

⚙️ Config​

Set acceptable-level (default is 1) to configure the acceptable nesting level.

analysis_options.yaml
dart_code_metrics:
  rules:
    - avoid-nested-switch-expressions:
        acceptable-level: 1

Example​

❌ Bad:

(int x, int y) getPoint() => (1, 1);

void main() {
  final value = switch (getPoint()) {
    // LINT: Avoid nested switch expressions. Try rewriting the code to remove nesting.
    (int y, int x) => switch (x) {
        > 0 => 5,
        == 0 => 6,
      },
    (int first, int second) => 2,
    (int x, int y) => 3,
  };
}

✅ Good:

(int x, int y) getPoint() => (1, 1);

void main() {
  final value = switch (getPoint()) {
    (int y, int x) => _validateX(x),
    (int first, int second) => 2,
    (int x, int y) => 3,
  };
}

int _validateX(int x) => switch (x) {
    > 0 => 5,
    == 0 => 6,
  };