From d5ecbd58ab29830bb8cf9ca1f9c82906d42df154 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Franz=20P=C3=B6schel?= <franz.poeschel@gmail.com>
Date: Mon, 20 Mar 2023 16:46:29 +0100
Subject: [PATCH] Add m_datasetDefined

Todo: Merge functionality with #1316
---
 include/openPMD/RecordComponent.hpp              |  3 +++
 include/openPMD/backend/BaseRecordComponent.hpp  |  8 ++++++++
 include/openPMD/backend/PatchRecordComponent.hpp |  3 +++
 src/backend/BaseRecordComponent.cpp              | 11 +++++++++++
 4 files changed, 25 insertions(+)

diff --git a/include/openPMD/RecordComponent.hpp b/include/openPMD/RecordComponent.hpp
index ad23dcebf1..525e96ca7f 100644
--- a/include/openPMD/RecordComponent.hpp
+++ b/include/openPMD/RecordComponent.hpp
@@ -440,12 +440,15 @@ OPENPMD_protected
 
     inline Data_t const &get() const
     {
+        // cannot call this in the const overload
+        // datasetDefined(*m_recordComponentData);
         return dynamic_cast<Data_t const &>(*m_attri);
     }
 
     inline Data_t &get()
     {
         auto &res = dynamic_cast<Data_t &>(*m_attri);
+        setDatasetDefined(res);
         return res;
     }
 
diff --git a/include/openPMD/backend/BaseRecordComponent.hpp b/include/openPMD/backend/BaseRecordComponent.hpp
index fb00e2f49e..1a2409cfdf 100644
--- a/include/openPMD/backend/BaseRecordComponent.hpp
+++ b/include/openPMD/backend/BaseRecordComponent.hpp
@@ -49,6 +49,10 @@ namespace internal
          * instead defined via light-weight attributes.
          */
         bool m_isConstant = false;
+        /*
+         * ... document this ...
+         */
+        bool m_datasetDefined = false;
 
         BaseRecordComponentData(BaseRecordComponentData const &) = delete;
         BaseRecordComponentData(BaseRecordComponentData &&) = delete;
@@ -114,6 +118,10 @@ class BaseRecordComponent : virtual public Attributable
         return dynamic_cast<Data_t &>(*m_attri);
     }
 
+    void setDatasetDefined(Data_t &);
+
+    bool datasetDefined() const;
+
     BaseRecordComponent();
 }; // BaseRecordComponent
 
diff --git a/include/openPMD/backend/PatchRecordComponent.hpp b/include/openPMD/backend/PatchRecordComponent.hpp
index ba9eb0255b..3265e7422b 100644
--- a/include/openPMD/backend/PatchRecordComponent.hpp
+++ b/include/openPMD/backend/PatchRecordComponent.hpp
@@ -121,12 +121,15 @@ OPENPMD_protected
 
     inline Data_t const &get() const
     {
+        // cannot call this in the const overload
+        // setDatasetDefined(*m_recordComponentData);
         return dynamic_cast<Data_t const &>(*m_attri);
     }
 
     inline Data_t &get()
     {
         auto &res = dynamic_cast<Data_t &>(*m_attri);
+        setDatasetDefined(res);
         return res;
     }
 }; // PatchRecordComponent
diff --git a/src/backend/BaseRecordComponent.cpp b/src/backend/BaseRecordComponent.cpp
index 813927f63d..c721e98b6f 100644
--- a/src/backend/BaseRecordComponent.cpp
+++ b/src/backend/BaseRecordComponent.cpp
@@ -91,4 +91,15 @@ BaseRecordComponent::BaseRecordComponent()
         std::make_shared<internal::BaseRecordComponentData>());
 }
 
+void BaseRecordComponent::setDatasetDefined(
+    internal::BaseRecordComponentData &data)
+{
+    data.m_datasetDefined = true;
+}
+
+bool BaseRecordComponent::datasetDefined() const
+{
+    auto & data = get();
+    return data.m_datasetDefined;
+}
 } // namespace openPMD