YCM and Jedi patches for faster Python completion, trade in type-information in completions for speed. Blog-post about my whole VIM setup coming soon.

1_ycm_speed_hacks.patch

From 49225f02ba22c79764e62c14d8f3747834e7547f Mon Sep 17 00:00:00 2001
From: Hans Pinckaers <[email protected]>
Date: Mon, 6 Aug 2018 07:53:19 +0200
Subject: [PATCH] Do not request type information (is slow)

---
 ycmd/completers/python/python_completer.py | 8 ++++----
 1 file changed, 4 insertions(+), 4 deletions(-)

diff --git a/ycmd/completers/python/python_completer.py b/ycmd/completers/python/python_completer.py
index ae45e32..b16233f 100644
--- a/ycmd/completers/python/python_completer.py
+++ b/ycmd/completers/python/python_completer.py
@@ -192,10 +192,10 @@ class PythonCompleter( Completer ):
     with self._jedi_lock:
       return [ responses.BuildCompletionData(
         insertion_text = completion.name,
-        extra_menu_info = completion.description,
-        detailed_info = completion.docstring(),
-        kind = completion.type,
-        extra_data = self._GetExtraData( completion )
+        extra_menu_info = "    ▸ jedi",
+        detailed_info = "",
+        kind = "",
+        extra_data = None
       ) for completion in self._GetJediScript( request_data ).completions() ]
 
 
-- 
2.7.4

2_jedi_speed_hacks.patch

From e657556c402a9dbe9705b63a16b6584c0f8c9f73 Mon Sep 17 00:00:00 2001
From: Hans Pinckaers <[email protected]>
Date: Mon, 6 Aug 2018 07:49:34 +0200
Subject: [PATCH] Return empty context in find function for speed when possible

---
 jedi/__init__.py        |  8 ++++++++
 jedi/api/completion.py  | 10 +++++++++-
 jedi/evaluate/finder.py |  5 ++++-
 3 files changed, 21 insertions(+), 2 deletions(-)

diff --git a/jedi/__init__.py b/jedi/__init__.py
index 84ec178..4255fd5 100644
--- a/jedi/__init__.py
+++ b/jedi/__init__.py
@@ -38,6 +38,14 @@ good text editor, while still having very good IDE features for Python.
 
 __version__ = '0.12.1'
 
+def init_speed_hacks(on):
+    global speed_hacks
+    speed_hacks = on
+
+def speed_hacks():
+    global speed_hacks
+    return speed_hacks
+
 from jedi.api import Script, Interpreter, set_debug_function, \
     preload_module, names
 from jedi import settings
diff --git a/jedi/api/completion.py b/jedi/api/completion.py
index 358d726..69b0f6f 100644
--- a/jedi/api/completion.py
+++ b/jedi/api/completion.py
@@ -3,7 +3,7 @@ from parso.python import tree
 from parso.tree import search_ancestor, Leaf
 
 from jedi._compatibility import Parameter
-from jedi import debug
+from jedi import debug, init_speed_hacks
 from jedi import settings
 from jedi.api import classes
 from jedi.api import helpers
@@ -91,6 +91,14 @@ class Completion:
         self._like_name = helpers.get_on_completion_name(self._module_node, code_lines, position)
         # The actual cursor position is not what we need to calculate
         # everything. We want the start of the name we're on.
+
+        # Some hacks to increase speed of Jedi
+        current_line = self._code_lines[position[0] - 1]
+        if '.' not in current_line and '(' not in current_line:
+            init_speed_hacks(True)
+        else:
+            init_speed_hacks(False)
+
         self._position = position[0], position[1] - len(self._like_name)
         self._call_signatures_method = call_signatures_method
 
diff --git a/jedi/evaluate/finder.py b/jedi/evaluate/finder.py
index 5e7043f..b2f5d81 100644
--- a/jedi/evaluate/finder.py
+++ b/jedi/evaluate/finder.py
@@ -17,7 +17,7 @@ check for -> a is a string). There's big potential in these checks.
 
 from parso.python import tree
 from parso.tree import search_ancestor
-from jedi import debug
+from jedi import debug, speed_hacks
 from jedi import settings
 from jedi.evaluate.context import AbstractInstanceContext
 from jedi.evaluate import compiled
@@ -53,6 +53,9 @@ class NameFinder(object):
         :params bool attribute_lookup: Tell to logic if we're accessing the
             attribute or the contents of e.g. a function.
         """
+        if speed_hacks():
+            return ContextSet()
+
         names = self.filter_name(filters)
         if self._found_predefined_types is not None and names:
             check = flow_analysis.reachability_check(
-- 
2.7.4

To apply go to YouCompleteMe (probably somewhere in ~/.vim/):
$ git am --signoff < 1_ycm_speed_hacks.patch

Then inside the jedi-package of YouCompleteMe (YouCompleteMe/third_party/ycmd/third_party/jedi):
$ git am --signoff < 2_jedi_speed_hacks.patch