add test cases for flatbuffers, test=develop (#4282)

lite/model_parser/flatbuffers/io_test.cc

@@ -43,7 +43,7 @@ void set_tensor(paddle::lite::Tensor* tensor,
 TEST(CombinedParamsDesc, Scope) {
   /* --------- Save scope ---------- */
   Scope scope;
-  std::vector<std::string> params_name({"var_0", "var_1"});
+  std::vector<std::string> params_name({"var_0", "var_1", "var_2"});
   // variable 0
   Variable* var_0 = scope.Var(params_name[0]);
   Tensor* tensor_0 = var_0->GetMutable<Tensor>();
@@ -52,6 +52,10 @@ TEST(CombinedParamsDesc, Scope) {
   Variable* var_1 = scope.Var(params_name[1]);
   Tensor* tensor_1 = var_1->GetMutable<Tensor>();
   set_tensor<int8_t>(tensor_1, std::vector<int64_t>({10, 1}));
+  // variable 3
+  Variable* var_2 = scope.Var(params_name[2]);
+  Tensor* tensor_2 = var_2->GetMutable<Tensor>();
+  set_tensor<int16_t>(tensor_2, std::vector<int64_t>({16, 1}));
   // Set combined parameters
   fbs::CombinedParamsDesc combined_param;
   std::set<std::string> params_set(params_name.begin(), params_name.end());
@@ -71,6 +75,11 @@ TEST(CombinedParamsDesc, Scope) {
     CHECK(var_l1);
     const Tensor& tensor_l1 = var_l1->Get<Tensor>();
     CHECK(TensorCompareWith(*tensor_1, tensor_l1));
+    // variable 2
+    Variable* var_l2 = scope_l.FindVar(params_name[2]);
+    CHECK(var_l2);
+    const Tensor& tensor_l2 = var_l2->Get<Tensor>();
+    CHECK(TensorCompareWith(*tensor_2, tensor_l2));
   };
   check_params(combined_param);