// TFSession's are referencing it.
TF_CAPI_EXPORT extern void TF_DeleteGraph(TF_Graph*);

// Operation being built. The underlying graph must outlive this.
typedef struct TF_OperationDescription TF_OperationDescription;

// Operation that has been added to the graph. Valid until the graph is
// deleted -- in particular adding a new operation to the graph does not
// invalidate old TF_Operation* pointers.

                  const char* name) {
  TF_OperationDescription* desc = TF_NewOperation(graph, "AddN", name);
  TF_Output inputs[2] = {l, r};
  TF_AddInputList(desc, inputs, 2);
  return TF_FinishOperation(desc, s);
}

void NegHelper(TF_Operation* n, TF_Graph* graph, TF_Status* s, const char* name,
               TF_Operation** op) {
  TF_OperationDescription* desc = TF_NewOperation(graph, "Neg", name);

  // Used to link graphs contained in TF_WhileParams to the parent graph that
  // will eventually contain the full while loop.
  TF_Graph* parent;
  TF_Output* parent_inputs;
};

struct TF_OperationDescription {
  TF_OperationDescription(TF_Graph* g, const char* op_type,
                          const char* node_name)
      : node_builder(node_name, op_type, g->graph.op_registry()), graph(g) {}

  return new TF_OperationDescription(graph, op_type, oper_name);
}

TF_OperationDescription* TF_NewOperation(TF_Graph* graph, const char* op_type,
                                         const char* oper_name) {
  mutex_lock l(graph->mu);
  return TF_NewOperationLocked(graph, op_type, oper_name);
}

void TF_SetDevice(TF_OperationDescription* desc, const char* device) {

    TF_AddInputList(desc_, inputs, TF_ARRAYSIZE(inputs));
  }

  ~CApiColocationTest() override {
    TF_DeleteGraph(graph_);
    TF_DeleteStatus(s_);
  }

  void SetViaStringList(TF_OperationDescription* desc,
                        const std::vector<string>& list) {
    std::unique_ptr<const void*[]> list_ptrs;
    std::unique_ptr<size_t[]> list_lens;
    StringVectorToArrays(list, &list_ptrs, &list_lens);

  // one cannot call ASSERT_* methods in non-void-returning functions (when
  // exceptions are disabled during compilation)
  void UseHelper(const std::vector<TF_Output>& inputs, TF_Operation** op) {
    TF_OperationDescription* desc =
        TF_NewOperation(host_graph_, func_name_, func_node_name_);
    for (auto input : inputs) {
      TF_AddInput(desc, input);
    }