Improved paste indentation by coping or cutting with starting indentation if possible

src/source_base.cpp

@@ -202,8 +202,23 @@ void Source::CommonView::cut() {
     Gtk::Clipboard::get()->set_text(selection);
     get_buffer()->erase(start, end);
   }
+  else {
+    Gtk::TextIter start, end;
+    get_buffer()->get_selection_bounds(start, end);
+    if(start.get_line() == end.get_line() || start.starts_line())
+      get_buffer()->cut_clipboard(Gtk::Clipboard::get());
+    else { // In order to improve paste indentation: copy entire starting line if only whitespaces before start iter
+      auto iter = start;
+      while(!iter.starts_line() && iter.backward_char() && (*iter == ' ' || *iter == '\t')) {
+      }
+      if(iter.starts_line()) {
+        Gtk::Clipboard::get()->set_text(get_buffer()->get_text(iter, end));
+        get_buffer()->erase(start, end);
+      }
       else
         get_buffer()->cut_clipboard(Gtk::Clipboard::get());
+    }
+  }
   keep_clipboard = true;
 }
 
@@ -268,9 +283,22 @@ void Source::CommonView::copy() {
     }
     Gtk::Clipboard::get()->set_text(selection);
   }
+  else {
+    Gtk::TextIter start, end;
+    get_buffer()->get_selection_bounds(start, end);
+    if(start.get_line() == end.get_line() || start.starts_line())
+      get_buffer()->copy_clipboard(Gtk::Clipboard::get());
+    else { // In order to improve paste indentation: copy entire starting line if only whitespaces before start iter
+      auto iter = start;
+      while(!iter.starts_line() && iter.backward_char() && (*iter == ' ' || *iter == '\t')) {
+      }
+      if(iter.starts_line())
+        Gtk::Clipboard::get()->set_text(get_buffer()->get_text(iter, end));
       else
         get_buffer()->copy_clipboard(Gtk::Clipboard::get());
     }
+  }
+}
 
 void Source::CommonView::copy_lines() {
   Gtk::TextIter start, end;