Update comments

slapos/recipe/gitclone.py

@@ -290,10 +290,7 @@ class Recipe(object):
                           cwd=self.location).strip() == self.revision
 
       if not revision_already_fetched:
-        # With --recurse-submodules, it will fetch the updated branches of the
-        # submodules as well as of the main repo.
-        check_call([self.git_command, 'fetch', '--all'],
-                    cwd=self.location)
+        check_call([self.git_command, 'fetch', '--all'], cwd=self.location)
 
       # If develop parameter is set, don't reset/update.
       # Otherwise, reset --hard
@@ -306,6 +303,10 @@ class Recipe(object):
       if not revision_already_fetched and not self.ignore_cloning_submodules:
         # Also update the submodule directory to the commit which parent
         # repository is pointing to.
+        # According to man-page of submodule, update also clones missing
+        # submodules and updating the working tree of the submodules. This is
+        # why we do update here only after we are ok with revision of parent
+        # repo being checked out to the desired one.
         # NOTE: This will put the submodule repo in a `Detached` state.
         check_call([self.git_command, 'submodule', 'update', '--recursive'],
                     cwd=self.location)