Merge branch 'pyHelp.AthContainers-20180430' into 'master'

AthContainers: Make AtomicConstAccessor easier to use from Python.

See merge request atlas/athena!10889

Control/AthContainers/AthContainers/AthContainersDict.h

@@ -20,6 +20,7 @@
 #include "AthContainers/OwnershipPolicy.h"
 #include "AthContainers/PackedParameters.h"
 #include "AthContainers/PackedContainer.h"
+#include "AthContainers/tools/AtomicConstAccessor.h"
 #include "AthContainers/debug.h"
 #include "AthLinks/DataLink.h"
 
@@ -110,6 +111,8 @@ INSTAN_TYPE(std::vector<double>);
 INSTAN_TYPE(std::vector<bool>);
 INSTAN_TYPE(std::vector<std::string>);
 
+template class SG::AtomicConstAccessor<unsigned int>;
+
 #undef ARGS1
 #undef ARGS2
 #undef INSTAN_TYPE

Control/AthContainers/AthContainers/selection.xml

@@ -78,6 +78,8 @@
   <class name="SG::AuxElement::ConstAccessor<std::vector<bool> >"/>
   <class name="SG::AuxElement::ConstAccessor<std::vector<std::string> >"/>
 
+  <class name="SG::AuxElement::AtomicConstAccessor<unsigned int>"/>
+
   <class name="SG::AuxElement::Accessor<char>"/>
   <class name="SG::AuxElement::Accessor<unsigned char>"/>
   <class name="SG::AuxElement::Accessor<int>"/>

Control/AthContainers/AthContainers/tools/AtomicConstAccessor.h

@@ -90,8 +90,11 @@ public:
   /**
    * @brief Fetch the variable for one element, as a const reference.
    * @param e The element for which to fetch the variable.
+   *
+   * As this class can be used only read-only for basic types, return
+   * the result by value.  That makes it easier to call from python.
    */
-  const_reference_type operator() (const AuxElement& e) const;
+  T operator() (const AuxElement& e) const;
 
 
   /**
@@ -102,9 +105,11 @@ public:
    * This allows retrieving aux data by container / index.
    * Looping over the index via this method will be faster then
    * looping over the elements of the container.
+   *
+   * As this class can be used only read-only for basic types, return
+   * the result by value.  That makes it easier to call from python.
    */
-  const_reference_type
-  operator() (const AuxVectorData& container, size_t index) const;
+  T operator() (const AuxVectorData& container, size_t index) const;
 
 
   /**

Control/AthContainers/AthContainers/tools/AtomicConstAccessor.icc

@@ -43,11 +43,13 @@ AtomicConstAccessor<T>::AtomicConstAccessor (const std::string& name,
 /**
  * @brief Fetch the variable for one element, as a const reference.
  * @param e The element for which to fetch the variable.
+ *
+ * As this class can be used only read-only for basic types, return
+ * the result by value.  That makes it easier to call from python.
  */
 template <class T>
 inline
-typename AtomicConstAccessor<T>::const_reference_type
-AtomicConstAccessor<T>::operator() (const AuxElement& e) const
+T AtomicConstAccessor<T>::operator() (const AuxElement& e) const
 {
   return reinterpret_cast<const_reference_type> (Base::operator() (e));
 }
@@ -61,12 +63,14 @@ AtomicConstAccessor<T>::operator() (const AuxElement& e) const
  * This allows retrieving aux data by container / index.
  * Looping over the index via this method will be faster then
  * looping over the elements of the container.
+ *
+ * As this class can be used only read-only for basic types, return
+ * the result by value.  That makes it easier to call from python.
  */
 template <class T>
 inline
-typename AtomicConstAccessor<T>::const_reference_type
-AtomicConstAccessor<T>::operator() (const AuxVectorData& container,
-                                    size_t index) const
+T AtomicConstAccessor<T>::operator() (const AuxVectorData& container,
+                                      size_t index) const
 {
   return reinterpret_cast<const_reference_type> (Base::operator() (container, index));
 }

Control/AthContainers/test/AtomicConstAccessor_test.cxx

@@ -82,7 +82,7 @@ void test1()
   assert (ityp2.auxid() == ityp2_id);
 
   static_assert (std::is_same<decltype(ityp2(b)),
-                              const std::atomic<int>&>::value, "test");
+                              int>::value, "test");
 
   SG::AtomicDecorator<int> ityp2_d ("anInt2");
   ityp2_d(b) = 11;
@@ -95,7 +95,7 @@ void test1()
   ityp3_d(cb) = 12;
   assert (12 == ityp3(cb));
 
-  assert (ityp3.getDataArray (v)+5 == &ityp3(cb));
+  assert (*(ityp3.getDataArray (v)+5) == ityp3(cb));
   static_assert (std::is_same<decltype(ityp3.getDataArray(v)),
                               const std::atomic<int>*>::value, "test");