DynamicList re-visited:

- shrink() should now correctly actually shrink
 - List::transfer(DynamicList&) invokes shrink() before transferring
   contents: otherwise the ununsed allocated space is never recovered
   until much, much later.
 - DynamicList::transfer(List&) no longer throws a FatalError when
   transferring in a smaller list. The original list contents are getting
   tossed away anyhow!

src/OpenFOAM/containers/Lists/DynamicList/DynamicList.H

@@ -115,39 +115,36 @@ public:
 
         // Access
 
-            //- Size of the underlying storage.
-            inline label allocSize() const;
+        //- Size of the underlying storage.
+        inline label allocSize() const;
 
 
         // Edit
 
-            //- Alter the list size.
-            //  When the new size is greater than the addressed list size, the
-            //  allocated list sizes is adjusted and the
-            //  addressed size does not change.
-            //  Otherwise the addressed list size is just reduced and the
-            //  allocated size does not change.
-            inline void setSize(const label);
+        //- Alter the list size.
+        //  When the new size is greater than the addressed list size, the
+        //  allocated list sizes is adjusted and the
+        //  addressed size does not change.
+        //  Otherwise the addressed list size is just reduced and the
+        //  allocated size does not change.
+        inline void setSize(const label);
 
-            //- Clear the list, i.e. set the size to zero.
-            //  Allocated size does not change
-            inline void clear();
+        //- Clear the list, i.e. set the size to zero.
+        //  Allocated size does not change
+        inline void clear();
 
-            //- Clear the list and delete storage.
-            inline void clearStorage();
+        //- Clear the list and delete storage.
+        inline void clearStorage();
 
-            //- Shrink the List<T> to the number of elements used
-            inline DynamicList<T, SizeInc, SizeMult, SizeDiv>& shrink();
+        //- Shrink the allocated space to the number of elements used.
+        //  Returns a reference to the DynamicList.
+        inline DynamicList<T, SizeInc, SizeMult, SizeDiv>& shrink();
 
-            //- Transfer the contents of the argument List into this List
-            //  and annull the argument list. Is same as List::transfer except
-            //  checks that you're not changing the underlying list to something
-            //  smaller than allocSize_.
-            inline void transfer(List<T>&);
+        //- Transfer contents of the argument List into this DynamicList
+        inline void transfer(List<T>&);
 
-            //- Transfer the contents of the argument DynamicList into this
-            //  DynamicList and annull the argument list.
-            inline void transfer(DynamicList<T, SizeInc, SizeMult, SizeDiv>&);
+        //- Transfer contents of the argument DynamicList into this DynamicList
+        inline void transfer(DynamicList<T, SizeInc, SizeMult, SizeDiv>&);
 
 
     // Member Operators
@@ -158,8 +155,7 @@ public:
         //- Remove and return the top element
         inline T remove();
 
-        //- Return non-const access to an element,
-        //  resizing the list if necessary
+        //- Return non-const access to an element, resizing list if necessary
         inline T& operator()(const label);
 
         //- Assignment of all addressed entries to the given value

src/OpenFOAM/containers/Lists/DynamicList/DynamicListI.H

@@ -26,7 +26,6 @@ License
 
 // * * * * * * * * * * * * * * * * Constructors  * * * * * * * * * * * * * * //
 
-//- Construct null
 template<class T, unsigned SizeInc, unsigned SizeMult, unsigned SizeDiv>
 inline Foam::DynamicList<T, SizeInc, SizeMult, SizeDiv>::DynamicList()
 :
@@ -37,7 +36,6 @@ inline Foam::DynamicList<T, SizeInc, SizeMult, SizeDiv>::DynamicList()
 }
 
 
-//- Construct given size
 template<class T, unsigned SizeInc, unsigned SizeMult, unsigned SizeDiv>
 inline Foam::DynamicList<T, SizeInc, SizeMult, SizeDiv>::DynamicList
 (
@@ -51,15 +49,14 @@ inline Foam::DynamicList<T, SizeInc, SizeMult, SizeDiv>::DynamicList
 }
 
 
-//- Construct given size
 template<class T, unsigned SizeInc, unsigned SizeMult, unsigned SizeDiv>
 inline Foam::DynamicList<T, SizeInc, SizeMult, SizeDiv>::DynamicList
 (
-    const UList<T>& s
+    const UList<T>& lst
 )
 :
-    List<T>(s),
-    allocSize_(s.size())
+    List<T>(lst),
+    allocSize_(lst.size())
 {}
 
 
@@ -114,31 +111,24 @@ template<class T, unsigned SizeInc, unsigned SizeMult, unsigned SizeDiv>
 inline Foam::DynamicList<T, SizeInc, SizeMult, SizeDiv>&
 Foam::DynamicList<T, SizeInc, SizeMult, SizeDiv>::shrink()
 {
-    allocSize_ = List<T>::size();
-    List<T>::setSize(allocSize_);
+    if (allocSize_ > List<T>::size())
+    {
+        allocSize_ = List<T>::size();
+        // force re-allocation/copying in List<T>::setSize() by temporarily
+        // faking a larger list size that will be truncated
+        List<T>::size(allocSize_+1);
+        List<T>::setSize(allocSize_);
+    }
     return *this;
 }
 
 
 template<class T, unsigned SizeInc, unsigned SizeMult, unsigned SizeDiv>
 inline void
-Foam::DynamicList<T, SizeInc, SizeMult, SizeDiv>::transfer(List<T>& l)
+Foam::DynamicList<T, SizeInc, SizeMult, SizeDiv>::transfer(List<T>& lst)
 {
-    if (l.size() < List<T>::size())
-    {
-        FatalErrorIn
-        (
-            "void DynamicList<T, SizeInc, SizeMult"
-            ", SizeDiv>::transfer(List<T>&)"
-        )   << "Cannot replace the underlying storage of this DynamicList"
-            << " of which " << List<T>::size() << " elements are used" << nl
-            << "with a List of size " << l.size() << abort(FatalError);
-    }
-    else
-    {
-        allocSize_ = l.size();
-        List<T>::transfer(l);   // take over storage
-    }
+    allocSize_ = lst.size();
+    List<T>::transfer(lst);   // take over storage, null lst
 }
 
 
@@ -146,11 +136,11 @@ template<class T, unsigned SizeInc, unsigned SizeMult, unsigned SizeDiv>
 inline void
 Foam::DynamicList<T, SizeInc, SizeMult, SizeDiv>::transfer
 (
-    DynamicList<T, SizeInc, SizeMult, SizeDiv>& l
+    DynamicList<T, SizeInc, SizeMult, SizeDiv>& lst
 )
 {
-    allocSize_ = l.allocSize();
-    List<T>::transfer(l);       // take over storage. Null l.
+    allocSize_ = lst.allocSize();
+    List<T>::transfer(lst);       // take over storage, null lst.
 }
 
 

src/OpenFOAM/containers/Lists/List/List.C

@@ -430,6 +430,9 @@ template<class T>
 template<unsigned SizeInc, unsigned SizeMult, unsigned SizeDiv>
 void Foam::List<T>::transfer(DynamicList<T, SizeInc, SizeMult, SizeDiv>& a)
 {
+    // shrink the allocated space to the number of elements used
+    a.shrink();
+
     if (this->v_) delete[] this->v_;
     this->size_ = a.size_;
     this->v_ = a.v_;

src/OpenFOAM/containers/Lists/UList/UList.C

@@ -45,7 +45,7 @@ void Foam::UList<T>::assign(const UList<T>& a)
 {
     if (a.size_ != this->size_)
     {
-        FatalErrorIn("UList<T>::operator=(const UList<T>&)")
+        FatalErrorIn("UList<T>::assign(const UList<T>&)")
             << "ULists have different sizes: "
             << this->size_ << " " << a.size_
             << abort(FatalError);