Issue #330 deferred for single values not working

Moved to sync functions
Added exception in EndStep if Perform Puts/Gets is missing

source/adios2/core/ADIOS.h

@@ -125,7 +125,7 @@ public:
 
     /**
      * Retrieve a reference pointer to an existing Operator object
-     * created with DeclareIO.
+     * created with DefineOperator.
      * @return if IO exists returns a reference to existing IO object inside
      * ADIOS, otherwise a nullptr
      */

source/adios2/core/Engine.tcc

@@ -68,13 +68,13 @@ namespace adios2
     void Engine::Put##L(Variable<T> &variable, const T &value)                 \
     {                                                                          \
         const T valueLocal = value;                                            \
-        Put##L(variable, &valueLocal);                                         \
+        PutSync(variable, &valueLocal);                                        \
     }                                                                          \
                                                                                \
     template <class T>                                                         \
     void Engine::Put##L(const std::string &variableName, const T &value)       \
     {                                                                          \
-        Put##L(FindVariable<T>(variableName), value);                          \
+        PutSync(FindVariable<T>(variableName), value);                         \
     }
 ADIOS2_FOREACH_LAUNCH_MODE(declare_launch_mode)
 #undef declare_launch_mode
@@ -125,13 +125,13 @@ ADIOS2_FOREACH_LAUNCH_MODE(declare_launch_mode)
     template <class T>                                                         \
     void Engine::Get##L(Variable<T> &variable, T &value)                       \
     {                                                                          \
-        Get##L(variable, &value);                                              \
+        GetSync(variable, &value);                                             \
     }                                                                          \
                                                                                \
     template <class T>                                                         \
     void Engine::Get##L(const std::string &variableName, T &value)             \
     {                                                                          \
-        Get##L(FindVariable<T>(variableName), value);                          \
+        GetSync(FindVariable<T>(variableName), value);                         \
     }
 ADIOS2_FOREACH_LAUNCH_MODE(declare_launch_mode)
 #undef declare_launch_mode

source/adios2/engine/bp/BPFileReader.cpp

@@ -60,13 +60,24 @@ StepStatus BPFileReader::BeginStep(StepMode mode, const float timeoutSeconds)
     return StepStatus::OK;
 }
 
-void BPFileReader::EndStep() { ++m_CurrentStep; }
+void BPFileReader::EndStep()
+{
+    if (m_DebugMode && !m_BP3Deserializer.m_PerformedGets)
+    {
+        throw std::invalid_argument("ERROR: existing variables subscribed with "
+                                    "GetDeferred, did you forget to call "
+                                    "PerformGets()?, in call to EndStep\n");
+    }
+
+    ++m_CurrentStep;
+}
 
 void BPFileReader::PerformGets()
 {
     const std::map<std::string, SubFileInfoMap> variablesSubfileInfo =
         m_BP3Deserializer.PerformGetsVariablesSubFileInfo(m_IO);
     ReadVariables(m_IO, variablesSubfileInfo);
+    m_BP3Deserializer.m_PerformedGets = true;
 }
 
 void BPFileReader::Close(const int transportIndex)

source/adios2/engine/bp/BPFileReader.tcc

@@ -40,6 +40,7 @@ void BPFileReader::GetDeferredCommon(Variable<T> &variable, T *data)
 {
     // returns immediately
     m_BP3Deserializer.GetDeferredVariable(variable, data);
+    m_BP3Deserializer.m_PerformedGets = false;
 }
 
 } // end namespace adios2

source/adios2/engine/bp/BPFileWriter.cpp

@@ -50,10 +50,19 @@ void BPFileWriter::PerformPuts()
     {
         PutSync(variableName);
     }
+
+    m_BP3Serializer.m_DeferredVariables.clear();
 }
 
 void BPFileWriter::EndStep()
 {
+    if (m_DebugMode && m_BP3Serializer.m_DeferredVariables.size() > 0)
+    {
+        throw std::invalid_argument("ERROR: existing variables subscribed with "
+                                    "PutDeferred, did you forget to call "
+                                    "PerformPuts()?, in call to EndStep\n");
+    }
+
     m_BP3Serializer.SerializeData(m_IO, true); // true: advances step
 }
 

source/adios2/toolkit/format/bp3/BP3Deserializer.h

@@ -31,6 +31,8 @@ public:
     /** BP Minifooter fields */
     Minifooter m_Minifooter;
 
+    bool m_PerformedGets = false;
+
     /**
      * Unique constructor
      * @param mpiComm