diff --git a/weboob/tools/application/formatters/iformatter.py b/weboob/tools/application/formatters/iformatter.py
index 6f5becadae24284d202c7d23365a27d10d9bf05f..bc44eec60a33c29c5ff995219c5d0d7cda09afc0 100644
--- a/weboob/tools/application/formatters/iformatter.py
+++ b/weboob/tools/application/formatters/iformatter.py
@@ -203,6 +203,16 @@ def format_dict(self, obj):
         """
         return NotImplementedError()
 
+    def format_collection(self, collection, only):
+        """
+        Format a collection to be human-readable.
+
+        :param collection: collection to format
+        :type collection: BaseCollection
+        :rtype: str
+        """
+        return NotImplementedError()
+
 
 class PrettyFormatter(IFormatter):
     def format_obj(self, obj, alias):
@@ -230,6 +240,16 @@ def get_title(self, obj):
     def get_description(self, obj):
         return None
 
+    def format_collection(self, collection, only):
+        if only is False or collection.basename in only:
+            if collection.basename and collection.title:
+                self.output(u'%s~ (%s) %s (%s)%s' %
+                     (self.BOLD, collection.basename, collection.title, collection.backend, self.NC))
+            else:
+                self.output(u'%s~ (%s) (%s)%s' %
+                     (self.BOLD, collection.basename, collection.backend, self.NC))
+
+
 def formatter_test_output(Formatter, obj):
     """
     Formats an object and returns output as a string.
diff --git a/weboob/tools/application/repl.py b/weboob/tools/application/repl.py
index e435b3c405e469612703007fa11d2469b8043cb4..9c8751ea79fa056acbfe2012320a0fec953caa86 100644
--- a/weboob/tools/application/repl.py
+++ b/weboob/tools/application/repl.py
@@ -1038,7 +1038,7 @@ def do_ls(self, line):
             if isinstance(res, Collection):
                 collections.append(res)
                 if sort is False:
-                    self._format_collection(res, only)
+                    self.formatter.format_collection(res, only)
             else:
                 if sort:
                     objects.append(res)
@@ -1050,7 +1050,7 @@ def do_ls(self, line):
             collections = self._merge_collections_with_same_path(collections)
             collections.sort(cmp=self.comp_object)
             for collection in collections:
-                self._format_collection(collection, only)
+                self.formatter.format_collection(collection, only)
             for obj in objects:
                 self._format_obj(obj, only)
 
@@ -1077,17 +1077,6 @@ def _merge_collections_with_same_path(self, collections):
                 to_return.append(collection)
         return to_return
 
-
-    def _format_collection(self, collection, only):
-        if only is False or collection.basename in only:
-            if collection.basename and collection.title:
-                print(u'%s~ (%s) %s (%s)%s' % \
-                (self.BOLD, collection.basename, collection.title, collection.backend, self.NC))
-            else:
-                print(u'%s~ (%s) (%s)%s' % \
-                (self.BOLD, collection.basename, collection.backend, self.NC))
-
-
     def _format_obj(self, obj, only):
         if only is False or not hasattr(obj, 'id') or obj.id in only:
             self.cached_format(obj)