falconGitHub

max-switch-cases

Same as max_switch_cases in Pyramid Lint

Path
lint/complexity/max-switch-cases
Default
Off, opt in
Origin
Pyramid Lint
Rule
265 of 512

Flags a switch statement with more than the configured number of cases.

A switch with many cases is often better modeled as a map lookup, polymorphism, or a sealed type with exhaustive handling. The rule counts non-default cases — the default clause is not counted — and reports at the switch when the count exceeds the threshold. Nested switches are checked independently.

Options

max-cases (integer, default: 10) — flag when the number of non-default cases exceeds this.

Invalid

example.dartdart
// Bad: switch with 11 cases exceeds max (default: 10)
void handleValue(int x) {
  switch (x) {
    case 1:
      print('one');
      break;
    case 2:
      print('two');
      break;
    case 3:
      print('three');
      break;
    case 4:
      print('four');
      break;
    case 5:
      print('five');
      break;
    case 6:
      print('six');
      break;
    case 7:
      print('seven');
      break;
    case 8:
      print('eight');
      break;
    case 9:
      print('nine');
      break;
    case 10:
      print('ten');
      break;
    case 11:
      print('eleven');
      break;
    default:
      print('other');
  }
}

// Bad: another switch with 12 cases
void processStatus(String status) {
  switch (status) {
    case 'active':
      print('active');
      break;
    case 'inactive':
      print('inactive');
      break;
    case 'pending':
      print('pending');
      break;
    case 'processing':
      print('processing');
      break;
    case 'completed':
      print('completed');
      break;
    case 'failed':
      print('failed');
      break;
    case 'cancelled':
      print('cancelled');
      break;
    case 'paused':
      print('paused');
      break;
    case 'queued':
      print('queued');
      break;
    case 'error':
      print('error');
      break;
    case 'warning':
      print('warning');
      break;
    case 'info':
      print('info');
      break;
    default:
      print('unknown');
  }
}
Switch statement has too many cases (max 10).
2void handleValue(int x) {
3 switch (x) {
Switch statement has too many cases (max 10).
43void processStatus(String status) {
44 switch (status) {

Valid

example.dartdart
// Good: switch with 9 cases within limit
void handleValue(int x) {
  switch (x) {
    case 1:
      print('one');
      break;
    case 2:
      print('two');
      break;
    case 3:
      print('three');
      break;
    case 4:
      print('four');
      break;
    case 5:
      print('five');
      break;
    case 6:
      print('six');
      break;
    case 7:
      print('seven');
      break;
    case 8:
      print('eight');
      break;
    case 9:
      print('nine');
      break;
    default:
      print('other');
  }
}

// Good: switch with 10 cases (at the limit)
void handleStatus(int code) {
  switch (code) {
    case 200:
      print('ok');
      break;
    case 201:
      print('created');
      break;
    case 204:
      print('no content');
      break;
    case 301:
      print('moved permanently');
      break;
    case 304:
      print('not modified');
      break;
    case 400:
      print('bad request');
      break;
    case 401:
      print('unauthorized');
      break;
    case 403:
      print('forbidden');
      break;
    case 404:
      print('not found');
      break;
    default:
      print('other');
  }
}

// Good: switch with 5 cases well under limit
void processType(String type) {
  switch (type) {
    case 'int':
      print('integer');
      break;
    case 'double':
      print('floating point');
      break;
    case 'string':
      print('text');
      break;
    case 'bool':
      print('boolean');
      break;
    default:
      print('unknown type');
  }
}

Configure max-switch-cases

Set its severity in falcon.json. See the configuration guide.

falcon.jsonjson
{
  "linter": {
    "rules": {
      "complexity": {
        "max-switch-cases": "error"
      }
    }
  }
}

Or silence one occurrence with a suppression comment; the reason is required.

example.dartdart
// falcon-ignore lint/complexity/max-switch-cases: <reason>