Class Jump

eval/compiler/flat_expr_builder.cc:157–190

A convenience wrapper for offset-calculating logic.

// A convenience wrapper for offset-calculating logic.
class Jump {
 public:
  // Default constructor for empty jump.
  //
  // Users must check that jump is non-empty before calling member functions.
  explicit Jump() : self_index_{-1, nullptr}, jump_step_(nullptr) {}
  Jump(ProgramStepIndex self_index, JumpStepBase* jump_step)
      : self_index_(self_index), jump_step_(jump_step) {}

  static absl::StatusOr<int> CalculateOffset(ProgramStepIndex base,
                                             ProgramStepIndex target) {
    if (target.subexpression != base.subexpression) {
      return absl::InternalError(
          "Jump target must be contained in the parent"
          "subexpression");
    }

    int offset = base.subexpression->CalculateOffset(base.index, target.index);
    return offset;
  }

  absl::Status set_target(ProgramStepIndex target) {
    CEL_ASSIGN_OR_RETURN(int offset, CalculateOffset(self_index_, target));

    jump_step_->set_jump_offset(offset);
    return absl::OkStatus();
  }

  bool exists() { return jump_step_ != nullptr; }

 private:
  ProgramStepIndex self_index_;
  JumpStepBase* jump_step_;
};

class CondVisitor {
 public: