Function ExpandTransformList4Macro

extensions/comprehensions_v2_macros.cc:236–278

}

absl::optional<Expr> ExpandTransformList4Macro(MacroExprFactory& factory,
                                               Expr& target,
                                               absl::Span<Expr> args) {
  if (args.size() != 4) {
    return factory.ReportError("transformList() requires 4 arguments");
  }
  if (!args[0].has_ident_expr() || args[0].ident_expr().name().empty()) {
    return factory.ReportErrorAt(
        args[0],
        "transformList() first variable name must be a simple identifier");
  }
  if (!args[1].has_ident_expr() || args[1].ident_expr().name().empty()) {
    return factory.ReportErrorAt(
        args[1],
        "transformList() second variable name must be a simple identifier");
  }
  if (args[0].ident_expr().name() == args[1].ident_expr().name()) {
    return factory.ReportErrorAt(args[0],
                                 "transformList() second variable must be "
                                 "different from the first variable");
  }
  if (args[0].ident_expr().name() == kAccumulatorVariableName) {
    return factory.ReportErrorAt(
        args[0], absl::StrCat("transformList() first variable name cannot be ",
                              kAccumulatorVariableName));
  }
  if (args[1].ident_expr().name() == kAccumulatorVariableName) {
    return factory.ReportErrorAt(
        args[1], absl::StrCat("transformList() second variable name cannot be ",
                              kAccumulatorVariableName));
  }
  std::string iter_var = args[0].ident_expr().name();
  std::string iter_var2 = args[1].ident_expr().name();
  Expr step = factory.NewCall(
      CelOperator::ADD, factory.NewAccuIdent(),
      factory.NewList(factory.NewListElement(std::move(args[3]))));
  step = factory.NewCall(CelOperator::CONDITIONAL, std::move(args[2]),
                         std::move(step), factory.NewAccuIdent());
  return factory.NewComprehension(std::move(iter_var), std::move(iter_var2),
                                  std::move(target), factory.AccuVarName(),
                                  factory.NewList(), factory.NewBoolConst(true),
                                  std::move(step), factory.NewAccuIdent());
}

Macro MakeTransformList4Macro() {
  auto status_or_macro =