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.addMethodDeclaration((MethodDeclaration node) {
    if (node.name.lexeme != 'build') return;

    final FunctionBody body = node.body;

    // Collect all return statements in the build method
    final List<ReturnStatement> returns = <ReturnStatement>[];
    _collectReturnStatementsForElement(body, returns);

    if (returns.length < 2) return;

    // Check if returns are in different branches of conditionals
    final Set<String> returnTypes = <String>{};
    for (final ReturnStatement ret in returns) {
      final Expression? expr = ret.expression;
      if (expr is InstanceCreationExpression) {
        returnTypes.add(expr.constructorName.type.name.lexeme);
      } else if (expr is MethodInvocation) {
        returnTypes.add(expr.methodName.name);
      }
    }

    // If different widget types are returned, warn
    if (returnTypes.length > 1) {
      reporter.atNode(node);
    }
  });
}