Fixes

Author: franzpoeschel

include/openPMD/backend/ScientificDefaults_internal.hpp

@@ -216,6 +216,11 @@ struct ConfigAttribute
 
     void read()
     {
+        if (attributeReaders.empty())
+        {
+            // No readers emplaced for this attribute
+            return;
+        }
         AttributeReadResult res = attribute_read_result::TypeUnmatched{};
         Parameter<Operation::READ_ATT> aRead;
         aRead.name = this->attrName;
@@ -237,11 +242,6 @@ struct ConfigAttribute
         }
 
         Attribute attribute(Attribute::from_any, std::move(*aRead.m_resource));
-        if (attributeReaders.empty())
-        {
-            // No readers emplaced for this attribute
-            return;
-        }
         for (auto &attributeReader : attributeReaders)
         {
 

src/backend/ScientificDefaults.cpp

@@ -552,6 +552,14 @@ void ScientificDefaults<Child>::defaults_impl(OpenpmdStandard standard)
         // We don't require unitSI for PatchRecordComponent
         //
         // addParentDefaults<RecordComponent, write>();
+        //
+        // But we still set it when writing. Doesnt hurt and some readers might
+        // expect it.
+        defaultAttribute("unitSI").template withSetter<PatchRecordComponent>(
+            1.0, &PatchRecordComponent::setUnitSI)
+            // Do NOT add a reader here.
+            // .withReader(float_types, require_type<double>())
+            (wor);
     }
     else if constexpr (auxiliary::IsTemplateBaseOf_v<BaseRecord, Child>)
     {