runWithReporter method

@override void runWithReporter(SaropaDiagnosticReporter reporter, SaropaContext context)

Override this method to implement your lint rule.

Use context to register callbacks for AST node types:

context.addMethodInvocation((node) {
  if (condition) {
    reporter.atNode(node);
  }
});

Implementation

@override
void runWithReporter(
  SaropaDiagnosticReporter reporter,
  SaropaContext context,
) {
  context.addSwitchPatternCase((SwitchPatternCase node) {
    // Check if the case body is just an if statement (possibly in a block)
    final List<Statement> statements = node.statements;
    if (statements.isEmpty) return;

    Statement? firstStatement;
    if (statements.length == 1) {
      firstStatement = statements.first;
    } else if (statements.length == 2 && statements[1] is BreakStatement) {
      // Allow if + break pattern
      firstStatement = statements.first;
    }

    if (firstStatement == null) return;

    // Check if it's an if statement or a block with just an if
    IfStatement? ifStmt;
    if (firstStatement is IfStatement) {
      ifStmt = firstStatement;
    } else if (firstStatement is Block &&
        firstStatement.statements.length == 1) {
      final Statement inner = firstStatement.statements.first;
      if (inner is IfStatement) {
        ifStmt = inner;
      }
    }

    if (ifStmt == null) return;

    // Check that the if statement doesn't already have a when guard on the case
    if (node.guardedPattern.whenClause != null) return;

    // Check that the if has no else branch (simpler to convert)
    if (ifStmt.elseStatement != null) return;

    // The if condition could be moved to a when guard
    reporter.atNode(ifStmt);
  });

  // Note: Traditional SwitchCase (`case 1:`) does NOT support when guards.
  // Only SwitchPatternCase (`case int n:`, `case Circle():`) supports when.
  // We intentionally do not flag traditional SwitchCase.
}