Improved autocompletion behaviour. See IPython issue #9658

3 files changed, 32 insertions, 17 deletions

diff --git a/prompt_toolkit/completion.py b/prompt_toolkit/completion.py
index 056274a1..7b26ef39 100644
--- a/prompt_toolkit/completion.py
+++ b/prompt_toolkit/completion.py
@@ -66,6 +66,22 @@ class Completion(object):
         else:
             return ''
 
+    def new_completion_from_position(self, position):
+        """
+        (Only for internal use!)
+        Get a new completion by splitting this one. Used by
+        `CommandLineInterface` when it needs to have a list of new completions
+        after inserting the common prefix.
+        """
+        assert isinstance(position, int)
+
+        return Completion(
+            text=self.text[position + self.start_position:],
+            display=self.display,
+            display_meta=self._display_meta,
+            get_display_meta=self._get_display_meta)
+
+
 
 class CompleteEvent(object):
     """
diff --git a/prompt_toolkit/interface.py b/prompt_toolkit/interface.py
index 33f4f712..c91f3833 100644
--- a/prompt_toolkit/interface.py
+++ b/prompt_toolkit/interface.py
@@ -857,21 +857,28 @@ class CommandLineInterface(object):
                         set_completions = True
                         select_first_anyway = False
 
-                        # When the commond part has to be inserted, and there
+                        # When the common part has to be inserted, and there
                         # is a common part.
                         if insert_common_part:
                             common_part = get_common_complete_suffix(document, completions)
                             if common_part:
-                                # Insert + run completer again.
+                                # Insert the common part, update completions.
                                 buffer.insert_text(common_part)
-                                async_completer()
-                                set_completions = False
+                                if len(completions) > 1:
+                                    # (Don't call `async_completer` again, but
+                                    # recalculate completions. See:
+                                    # https://github.com/ipython/ipython/issues/9658)
+                                    completions[:] = [
+                                        c.new_completion_from_position(len(common_part))
+                                        for c in completions]
+                                else:
+                                    set_completions = False
                             else:
                                 # When we were asked to insert the "common"
                                 # prefix, but there was no common suffix but
                                 # still exactly one match, then select the
                                 # first. (It could be that we have a completion
-                                # which does * expension, like '*.py', with
+                                # which does * expansion, like '*.py', with
                                 # exactly one match.)
                                 if len(completions) == 1:
                                     select_first_anyway = True
diff --git a/prompt_toolkit/key_binding/bindings/completion.py b/prompt_toolkit/key_binding/bindings/completion.py
index 6c7a9891..4903900b 100644
--- a/prompt_toolkit/key_binding/bindings/completion.py
+++ b/prompt_toolkit/key_binding/bindings/completion.py
@@ -21,19 +21,11 @@ def generate_completions(event):
     """
     b = event.current_buffer
 
-    def second_tab():
-        if b.complete_state:
-            b.complete_next()
-        else:
-            event.cli.start_completion(select_first=True)
-
-    # On the second tab-press, or when already navigating through
-    # completions.
-    if event.is_repeat or b.complete_state:
-        second_tab()
+    # When already navigating through completions, select the next one.
+    if b.complete_state:
+        b.complete_next()
     else:
-        event.cli.start_completion(insert_common_part=True,
-                                   select_first=False)
+        event.cli.start_completion(insert_common_part=True, select_first=False)
 
 
 def display_completions_like_readline(event):