Merge pull request #11591 from memeplex/fix-emacs-completions

Make all_completions use new completion code

IPython/core/completer.py

@@ -1134,10 +1134,15 b' class IPCompleter(Completer):'
                 self.dict_key_matches,
             ]
 
-    def all_completions(self, text):
+    def all_completions(self, text) -> List[str]:
         """
-        Wrapper around the complete method for the benefit of emacs.
+        Wrapper around the completions method for the benefit of emacs.
         """
+        prefix = text[:text.rfind(".") + 1]
+        with provisionalcompleter():
+            return list(map(lambda c: prefix + c.text,
+                   self.completions(text, len(text))))
+
         return self.complete(text)[1]
 
     def _clean_glob(self, text):