Support counts for undo/redo

src/buffer.cc

@@ -310,31 +310,38 @@ void Buffer::commit_undo_group()
     m_history_cursor = node;
 }
 
-bool Buffer::undo() noexcept
+bool Buffer::undo(size_t count) noexcept
 {
     commit_undo_group();
 
     if (not m_history_cursor->parent)
         return false;
 
+    while (count-- and m_history_cursor->parent)
+    {
         for (const Modification& modification : m_history_cursor->undo_group | reverse())
             apply_modification(modification.inverse());
 
         m_history_cursor = m_history_cursor->parent;
+    }
+
     return true;
 }
 
-bool Buffer::redo() noexcept
+bool Buffer::redo(size_t count) noexcept
 {
     if (not m_history_cursor->redo_child)
         return false;
 
     kak_assert(m_current_undo_group.empty());
 
+    while (count-- and m_history_cursor->redo_child)
+    {
         m_history_cursor = m_history_cursor->redo_child.get();
 
         for (const Modification& modification : m_history_cursor->undo_group)
             apply_modification(modification);
+    }
     return true;
 }
 
@@ -826,8 +833,8 @@ UnitTest test_undo{[]()
     buffer.commit_undo_group();
     buffer.erase({2, 1}, {2, 5});                             // change 5
     buffer.commit_undo_group();
-    buffer.undo();
-    buffer.redo();
+    buffer.undo(2);
+    buffer.redo(2);
     buffer.undo();
     buffer.replace(2_line, buffer.end_coord(), "foo");        // change 6
     buffer.commit_undo_group();

src/buffer.hh

@@ -132,8 +132,8 @@ public:
     void           set_fs_timestamp(timespec ts);
 
     void           commit_undo_group();
-    bool           undo() noexcept;
-    bool           redo() noexcept;
+    bool           undo(size_t count = 1) noexcept;
+    bool           redo(size_t count = 1) noexcept;
     bool           move_to(size_t history_id) noexcept;
 
     String         string(ByteCoord begin, ByteCoord end) const;

src/normal.cc

@@ -1414,37 +1414,34 @@ void restore_selections(Context& context, NormalParams params)
     context.print_status({format("Restored selections from register '{}'", reg), get_face("Information")});
 }
 
-void undo(Context& context, NormalParams)
+void undo(Context& context, NormalParams params)
 {
     Buffer& buffer = context.buffer();
     size_t timestamp = buffer.timestamp();
-    bool res = buffer.undo();
-    if (res)
+    if (buffer.undo(std::max(1, params.count)))
     {
         auto ranges = compute_modified_ranges(buffer, timestamp);
         if (not ranges.empty())
             context.selections_write_only() = std::move(ranges);
         context.selections().avoid_eol();
     }
-    else if (not res)
+    else
         context.print_status({ "nothing left to undo", get_face("Information") });
 }
 
-void redo(Context& context, NormalParams)
+void redo(Context& context, NormalParams params)
 {
     using namespace std::placeholders;
     Buffer& buffer = context.buffer();
     size_t timestamp = buffer.timestamp();
-    bool res = buffer.redo();
-    if (res)
+    if (buffer.redo(std::max(1, params.count)))
     {
         auto ranges = compute_modified_ranges(buffer, timestamp);
         if (not ranges.empty())
             context.selections_write_only() = std::move(ranges);
         context.selections().avoid_eol();
     }
-
-    else if (not res)
+    else
         context.print_status({ "nothing left to redo", get_face("Information") });
 }