Buffer: replace reset_undo_data with a NoUndo flag

src/buffer.cc

@@ -14,7 +14,7 @@ namespace Kakoune
 
 Buffer::Buffer(String name, Flags flags,
                String initial_content)
-    : m_name(std::move(name)), m_flags(flags),
+    : m_name(std::move(name)), m_flags(flags | Flags::NoUndo),
       m_history(), m_history_cursor(m_history.begin()),
       m_last_save_undo_index(0),
       m_timestamp(0),
@@ -26,7 +26,6 @@ Buffer::Buffer(String name, Flags flags,
         initial_content += '\n';
     do_insert(begin(), std::move(initial_content));
 
-
     Editor editor_for_hooks(*this);
     Context context(editor_for_hooks);
     if (flags & Flags::File and flags & Flags::New)
@@ -36,7 +35,8 @@ Buffer::Buffer(String name, Flags flags,
 
     m_hook_manager.run_hook("BufCreate", m_name, context);
 
-    reset_undo_data();
+    // now we may begin to record undo data
+    m_flags = flags;
 }
 
 Buffer::~Buffer()
@@ -148,6 +148,9 @@ String Buffer::string(const BufferIterator& begin, const BufferIterator& end) co
 
 void Buffer::begin_undo_group()
 {
+    if (m_flags & Flags::NoUndo)
+        return;
+
     assert(m_current_undo_group.empty());
     m_history.erase(m_history_cursor, m_history.end());
 
@@ -159,6 +162,9 @@ void Buffer::begin_undo_group()
 
 void Buffer::end_undo_group()
 {
+    if (m_flags & Flags::NoUndo)
+        return;
+
     if (m_current_undo_group.empty())
         return;
 
@@ -217,13 +223,6 @@ bool Buffer::redo()
     return true;
 }
 
-void Buffer::reset_undo_data()
-{
-   m_history.clear();
-   m_history_cursor = m_history.end();
-   m_current_undo_group.clear();
-}
-
 void Buffer::check_invariant() const
 {
     ByteCount start = 0;
@@ -370,9 +369,9 @@ void Buffer::insert(BufferIterator pos, String content)
     if (pos.is_end() and content.back() != '\n')
         content += '\n';
 
-    m_current_undo_group.emplace_back(Modification::Insert, pos,
-                                      std::move(content));
-    do_insert(pos, m_current_undo_group.back().content);
+    if (not (m_flags & Flags::NoUndo))
+        m_current_undo_group.emplace_back(Modification::Insert, pos, content);
+    do_insert(pos, content);
 }
 
 void Buffer::erase(BufferIterator begin, BufferIterator end)
@@ -383,8 +382,9 @@ void Buffer::erase(BufferIterator begin, BufferIterator end)
     if (begin == end)
         return;
 
-    m_current_undo_group.emplace_back(Modification::Erase, begin,
-                                      string(begin, end));
+    if (not (m_flags & Flags::NoUndo))
+        m_current_undo_group.emplace_back(Modification::Erase, begin,
+                                          string(begin, end));
     do_erase(begin, end);
 }
 

src/buffer.hh

@@ -100,7 +100,8 @@ public:
         None = 0,
         File = 1,
         New  = 2,
-        Fifo = 4
+        Fifo = 4,
+        NoUndo = 8,
     };
 
     Buffer(String name, Flags flags, String initial_content = "\n");
@@ -121,7 +122,6 @@ public:
     void           end_undo_group();
     bool           undo();
     bool           redo();
-    void           reset_undo_data();
 
     String         string(const BufferIterator& begin,
                           const BufferIterator& end) const;

src/commands.cc

@@ -231,7 +231,7 @@ Buffer* open_fifo(const String& name , const String& filename, Context& context)
     int fd = open(filename.c_str(), O_RDONLY | O_CLOEXEC);
     if (fd < 0)
        throw runtime_error("unable to open " + filename);
-    Buffer* buffer = new Buffer(name, Buffer::Flags::Fifo);
+    Buffer* buffer = new Buffer(name, Buffer::Flags::Fifo | Buffer::Flags::NoUndo);
 
     buffer->hook_manager().add_hook("BufClose",
         [fd, buffer](const String&, const Context&) {
@@ -250,7 +250,6 @@ Buffer* open_fifo(const String& name , const String& filename, Context& context)
         buffer->insert(buffer->end()-1,
                        count > 0 ? String(data, data+count)
                                   : "*** kak: fifo closed ***\n");
-        buffer->reset_undo_data();
         ClientManager::instance().redraw_clients();
         if (count <= 0)
         {

src/debug.cc

@@ -13,7 +13,7 @@ static Buffer& get_or_create_debug_buffer()
     Buffer* buffer = BufferManager::instance().get_buffer(debug_buffer_name);
 
     if (not buffer)
-        buffer = new Buffer(debug_buffer_name, Buffer::Flags::None, "");
+        buffer = new Buffer(debug_buffer_name, Buffer::Flags::NoUndo);
 
     assert(buffer);
     return *buffer;
@@ -25,7 +25,6 @@ void write_debug(const String& str)
     Editor editor(debug_buffer);
     editor.select(debug_buffer.end()-1);
     editor.insert(str + "\n");
-    debug_buffer.reset_undo_data();
 }
 
 }

src/file.cc

@@ -85,7 +85,7 @@ Buffer* create_buffer_from_file(const String& filename)
     if (Buffer* buffer = BufferManager::instance().get_buffer(filename))
         delete buffer;
 
-    Buffer* buffer = new Buffer(filename, Buffer::Flags::File, "");
+    Buffer* buffer = new Buffer(filename, Buffer::Flags::File | Buffer::Flags::NoUndo);
 
     String content;
     char buf[256];
@@ -131,8 +131,8 @@ Buffer* create_buffer_from_file(const String& filename)
     if (*(buffer->end() - 2) == '\n')
         buffer->erase(buffer->end() - 1, buffer->end());
 
-    // it never happened, buffer always was like that
-    buffer->reset_undo_data();
+    // enable undo data recording
+    buffer->flags() &= ~Buffer::Flags::NoUndo;
 
     return buffer;
 }

src/main.cc

@@ -612,7 +612,7 @@ void create_local_client(const String& file)
         }
     }
     else
-        buffer = new Buffer("*scratch*", Buffer::Flags::None);
+        buffer = new Buffer("*scratch*", Buffer::Flags::NoUndo);
 
     ClientManager::instance().create_client(
         std::unique_ptr<UserInterface>{ui}, *buffer, 0);