Move change listener registration to BufferChangeListener_AutoRegister

DynamicSelectionList now just inherit from this class, so that
the registration logic can be shared.

3 files changed, 58 insertions, 57 deletions

diff --git a/src/buffer.hh b/src/buffer.hh
index f3c80afc..260c00a0 100644
--- a/src/buffer.hh
+++ b/src/buffer.hh
@@ -244,6 +244,58 @@ constexpr Buffer::Flags operator~(Buffer::Flags lhs)
     return (Buffer::Flags)(~(int)lhs);
 }
 
+class BufferChangeListener_AutoRegister : public BufferChangeListener
+{
+public:
+    BufferChangeListener_AutoRegister(const Buffer& buffer)
+        : m_buffer(&buffer)
+    {
+        m_buffer->change_listeners().insert(this);
+    }
+
+    BufferChangeListener_AutoRegister(const BufferChangeListener_AutoRegister& other)
+        : m_buffer(other.m_buffer)
+    {
+        m_buffer->change_listeners().insert(this);
+    }
+
+    BufferChangeListener_AutoRegister(BufferChangeListener_AutoRegister&& other)
+        : m_buffer(other.m_buffer)
+    {
+        m_buffer->change_listeners().insert(this);
+    }
+
+    ~BufferChangeListener_AutoRegister()
+    {
+        m_buffer->change_listeners().erase(this);
+    }
+
+    BufferChangeListener_AutoRegister& operator=(const BufferChangeListener_AutoRegister& other)
+    {
+        if (m_buffer != other.m_buffer)
+        {
+            m_buffer->change_listeners().erase(this);
+            m_buffer = other.m_buffer;
+            m_buffer->change_listeners().insert(this);
+        }
+        return *this;
+    }
+
+    BufferChangeListener_AutoRegister& operator=(BufferChangeListener_AutoRegister&& other)
+    {
+        if (m_buffer != other.m_buffer)
+        {
+            m_buffer->change_listeners().erase(this);
+            m_buffer = other.m_buffer;
+            m_buffer->change_listeners().insert(this);
+        }
+        return *this;
+    }
+
+    const Buffer& buffer() const { return *m_buffer; }
+private:
+    const Buffer* m_buffer;
+};
 
 }
 
diff --git a/src/dynamic_selection_list.cc b/src/dynamic_selection_list.cc
index bca16293..a258ddd7 100644
--- a/src/dynamic_selection_list.cc
+++ b/src/dynamic_selection_list.cc
@@ -5,55 +5,12 @@ namespace Kakoune
 
 DynamicSelectionList::DynamicSelectionList(const Buffer& buffer,
                                            SelectionList selections)
-    : m_buffer(&buffer), SelectionList(std::move(selections))
+    : SelectionList(std::move(selections)),
+      BufferChangeListener_AutoRegister(buffer)
 {
-    m_buffer->change_listeners().insert(this);
     check_invariant();
 }
 
-DynamicSelectionList::~DynamicSelectionList()
-{
-    m_buffer->change_listeners().erase(this);
-}
-
-DynamicSelectionList::DynamicSelectionList(const DynamicSelectionList& other)
-    : SelectionList(other), m_buffer(other.m_buffer)
-{
-    m_buffer->change_listeners().insert(this);
-}
-
-DynamicSelectionList& DynamicSelectionList::operator=(const DynamicSelectionList& other)
-{
-    SelectionList::operator=((const SelectionList&)other);
-    if (m_buffer != other.m_buffer)
-    {
-        m_buffer->change_listeners().erase(this);
-        m_buffer = other.m_buffer;
-        m_buffer->change_listeners().insert(this);
-    }
-    check_invariant();
-    return *this;
-}
-
-DynamicSelectionList::DynamicSelectionList(DynamicSelectionList&& other)
-    : SelectionList(std::move(other)), m_buffer(other.m_buffer)
-{
-    m_buffer->change_listeners().insert(this);
-}
-
-DynamicSelectionList& DynamicSelectionList::operator=(DynamicSelectionList&& other)
-{
-    SelectionList::operator=(std::move(other));
-    if (m_buffer != other.m_buffer)
-    {
-        m_buffer->change_listeners().erase(this);
-        m_buffer = other.m_buffer;
-        m_buffer->change_listeners().insert(this);
-    }
-    check_invariant();
-    return *this;
-}
-
 DynamicSelectionList& DynamicSelectionList::operator=(SelectionList selections)
 {
     SelectionList::operator=(std::move(selections));
@@ -64,9 +21,10 @@ DynamicSelectionList& DynamicSelectionList::operator=(SelectionList selections)
 void DynamicSelectionList::check_invariant() const
 {
 #ifdef KAK_DEBUG
+    const Buffer* buf = &buffer();
     for (auto& sel : *this)
     {
-        assert(m_buffer == &sel.buffer());
+        assert(buf == &sel.buffer());
         sel.check_invariant();
     }
 #endif
diff --git a/src/dynamic_selection_list.hh b/src/dynamic_selection_list.hh
index 4ae34969..34f4c05c 100644
--- a/src/dynamic_selection_list.hh
+++ b/src/dynamic_selection_list.hh
@@ -6,32 +6,23 @@
 namespace Kakoune
 {
 
-class DynamicSelectionList : public SelectionList, public BufferChangeListener
+class DynamicSelectionList : public SelectionList,
+                             public BufferChangeListener_AutoRegister
 {
 public:
     using iterator = SelectionList::iterator;
     using const_iterator = SelectionList::const_iterator;
 
     DynamicSelectionList(const Buffer& buffer, SelectionList selections = {});
-    ~DynamicSelectionList();
-
-    DynamicSelectionList(const DynamicSelectionList& other);
-    DynamicSelectionList& operator=(const DynamicSelectionList& other);
-    DynamicSelectionList(DynamicSelectionList&& other);
-    DynamicSelectionList& operator=(DynamicSelectionList&& other);
 
     DynamicSelectionList& operator=(SelectionList selections);
     void check_invariant() const;
 
-    const Buffer& buffer() const { return *m_buffer; }
-
 private:
     void on_insert(const BufferIterator& begin,
                    const BufferIterator& end) override;
     void on_erase(const BufferIterator& begin,
                   const BufferIterator& end) override;
-
-    const Buffer* m_buffer;
 };
 
 };