deffered error : (error "\"AssertionError()\"")

[Muldfox]

SOLVED - Look at the comment down below on how I managed to "fix" my issue.

OS: Windows 10 Pro (Version: 1809, OS Build 17763.292)
Python version: 3.6.7
Emacs version: 26.1
Jedi PIP version: 0.2.7
Jedi MELPA version: 0.13.2

I'm having some oddities with Jedi where when I'm inside a python file (this one in particular has around 200 lines of code), Jedi will give me the completion box/menu after dots, but only in the first lines. When I go to around line 180, all of a sudden the completion/suggestion menu won't appear after dot. That is when I get deffered error : (error "\"AssertionError()\"").

So basically, around line 1-50, I get the completion menu with all kinds of suggestions (that I haven't even used in the file). But around line 180 no menu pops up, and that's where I get the AssertionError.

I pulled up the epc buffer and it just keeps telling me: ERROR:epc:AssertionError().

Example in the beginning of the file where it works:
https://i.imgur.com/q2Oohd7.png

Example further down in the file where it doesn't work:
https://i.imgur.com/Frqw2kQ.png

I have tried re-installing the jedi-server to no avail. It gives the same exact results.
I am really new to emacs, so I'm obviously doing something wrong here.

Here is my init.el file, for reference:
https://pastebin.com/bF3svCkw

Here is the jedi setup info (jedi:show-setup-info):

;; Emacs Lisp version:
(:emacs-version "26.1" :jedi-version "0.2.7" :python-environment-version "0.0.2alpha0")
;; Python version:
((:name "sys" :file nil :version "3.6.7 (v3.6.7:6ec5cf24b7, Oct 20 2018, 13:35:33) [MSC v.1900 64 bit (AMD64)]")
 (:name "jedi" :file "c:\\Users\\xxxxx\\AppData\\Local\\Programs\\Python\\Python36\\lib\\site-packages\\jedi\\__init__.py" :version "0.13.2")
 (:name "epc" :file "c:\\Users\\xxxxx\\AppData\\Local\\Programs\\Python\\Python36\\lib\\site-packages\\epc\\__init__.py" :version "0.0.5")
 (:name "sexpdata" :file "c:\\Users\\xxxxx\\AppData\\Local\\Programs\\Python\\Python36\\lib\\site-packages\\sexpdata.py" :version "0.0.3"))
;; Command line:
(:virtualenv "c:/Users/xxxxx/AppData/Local/Programs/Python/Python36/python.exe" :virtualenv-version "Python 3.6.7\n")
;; Customization:
((jedi:complete-on-dot . t)
 (jedi:doc-display-buffer . display-buffer)
 (jedi:doc-hook view-mode)
 (jedi:doc-mode . rst-mode)
 (jedi:environment-root)
 (jedi:environment-virtualenv)
 (jedi:get-in-function-call-delay . 1000)
 (jedi:get-in-function-call-timeout . 3000)
 (jedi:goto-definition-config
  (nil nil nil)
  (t nil nil)
  (nil definition nil)
  (t definition nil)
  (nil nil t)
  (t nil t)
  (nil definition t)
  (t definition t))
 (jedi:goto-definition-marker-ring-length . 16)
 (jedi:imenu-create-index-function . jedi:create-nested-imenu-index)
 (jedi:import-python-el-settings . t)
 (jedi:install-imenu)
 (jedi:install-python-jedi-dev-command "pip" "install" "--upgrade" "git+https://github.com/davidhalter/jedi.git@master#egg=jedi")
 (jedi:key-complete .
		    [C-tab])
 (jedi:key-goto-definition .
			   [67108910])
 (jedi:key-goto-definition-pop-marker .
				      [67108908])
 (jedi:key-related-names . "�r")
 (jedi:key-show-doc . "�d")
 (jedi:server-args)
 (jedi:server-command "c:/Users/xxxxx/.emacs.d/.python-environments/default/Scripts/jediepcserver.exe")
 (jedi:setup-keys . t)
 (jedi:tooltip-method pos-tip popup)
 (jedi:use-shortcuts)
 (python-environment-default-root-name . "default")
 (python-environment-directory . "~/.emacs.d/.python-environments")

I'm sorry if I forgot some important information. If needed I'll update as fast as possible.

[Muldfox]

So, I finally got it to work! I downgraded Jedi to version 0.11.0 inside of the environment.

pip install Jedi==0.11.0 inside of the environment did the trick. Not sure what the exact issue was, but it's working now.

Jedi:show-setup-info in working condition:

;; Emacs Lisp version:
(:emacs-version "26.1" :jedi-version "0.2.7" :python-environment-version "0.0.2alpha0")
;; Python version:
((:name "sys" :file nil :version "3.6.7 (v3.6.7:6ec5cf24b7, Oct 20 2018, 13:35:33) [MSC v.1900 64 bit (AMD64)]")
 (:name "jedi" :file "c:\\users\\xxxxx\\.emacs.d\\.python-environments\\default\\lib\\site-packages\\jedi\\__init__.py" :version "0.11.0")
 (:name "epc" :file "c:\\users\\xxxxxx\\.emacs.d\\.python-environments\\default\\lib\\site-packages\\epc\\__init__.py" :version "0.0.5")
 (:name "sexpdata" :file "c:\\users\\xxxxx\\.emacs.d\\.python-environments\\default\\lib\\site-packages\\sexpdata.py" :version "0.0.3"))
;; Command line:
(:virtualenv "c:/Users/xxxxxx/AppData/Local/Programs/Python/Python36/python.exe" :virtualenv-version "Python 3.6.7\n")
;; Customization:
((jedi:complete-on-dot . t)
 (jedi:doc-display-buffer . display-buffer)
 (jedi:doc-hook view-mode)
 (jedi:doc-mode . rst-mode)
 (jedi:environment-root)
 (jedi:environment-virtualenv)
 (jedi:get-in-function-call-delay . 1000)
 (jedi:get-in-function-call-timeout . 3000)
 (jedi:goto-definition-config
  (nil nil nil)
  (t nil nil)
  (nil definition nil)
  (t definition nil)
  (nil nil t)
  (t nil t)
  (nil definition t)
  (t definition t))
 (jedi:goto-definition-marker-ring-length . 16)
 (jedi:imenu-create-index-function . jedi:create-nested-imenu-index)
 (jedi:import-python-el-settings . t)
 (jedi:install-imenu)
 (jedi:install-python-jedi-dev-command "pip" "install" "--upgrade" "git+https://github.com/davidhalter/jedi.git@master#egg=jedi")
 (jedi:key-complete .
		    [C-tab])
 (jedi:key-goto-definition .
			   [67108910])
 (jedi:key-goto-definition-pop-marker .
				      [67108908])
 (jedi:key-related-names . "�r")
 (jedi:key-show-doc . "�d")
 (jedi:server-args)
 (jedi:server-command "c:/Users/xxxxxx/.emacs.d/.python-environments/default/Scripts/jediepcserver.exe")
 (jedi:setup-keys . t)
 (jedi:tooltip-method pos-tip popup)
 (jedi:use-shortcuts)
 (python-environment-default-root-name . "default")
 (python-environment-directory . "~/.emacs.d/.python-environments")
 (python-environment-virtualenv "python" "-m" "venv"))

[glyph]

I have the same issue.

For me, this typically starts (in *epc:server*) - ERROR:epc:AttributeError("'FStringStart' object has no attribute 'children'",).

Hopefully that's a hint!

[immerrr]

I'll try to reproduce it locally right now, but would be very nice if someone could provide some repro steps.

[immerrr]

FStringStart thing is related to parso: https://github.com/davidhalter/parso/search?q=FStringStart&unscoped_q=FStringStart

and could be related to the recent update in Jedi: davidhalter/jedi#1063 (comment) that mentioned a parso upgrade.

Did any of you upgrade jedi, emacs-jedi or parso recently?

[Muldfox]

Did any of you upgrade jedi, emacs-jedi or parso recently?

I haven't upgraded anything individually. I just installed whatever is in my init.el file through MELPA, as well as the modules that "jedi:install-server" will automatically add to the python environment. But what turned out solving it for me, was to downgrade to Jedi 0.11.0 in the python environment that Jedi is using (~/.emacs.d/.python-environment/default).

Here is my init.el file.

This is how I did it, unnecessary steps and all:
(I'm using Windows 10 Pro, Emacs 26.1, Python 3.6.7)

1. Using my init.el will install everything needed through MELPA.
2. Start Emacs, let packages and everything setup.
3. Restart Emacs.
4. Find and open Python file.
5. M-x jedi:install-server
6. M-x jedi:start-dedicated-server
7. Restart Emacs
8. Go to Python file and experience the assertion error bug. Completion will work on the top lines of my ~200 lines long file. Like, completion suggestions/menu will appear around line 50. But at around line 180, I will get no suggestions what so ever.

I tried re-installing the Jedi server multiple times to no avail.

Again, what solved it for me was to uninstall the current Jedi python module (0.13.2) and install Jedi version 0.11.0 instead (inside of the default python environment "~/.emacs.d/.python-environments/default").

And boom, the Jedi completion works flawlessly! No matter how big the file is. It's been working without any issues whatsoever the entire day after I downgraded the Jedi python module inside of the environment.

[glyph]

Yes. I have a script that reinstalls all my packages that I run once a week or so, so I've upgraded everything a couple of days ago.

$ ~/.emacs.d/.python-environments/default/bin/pip freeze
epc==0.0.5
jedi==0.13.2
jediepcserver==0.2.7
parso==0.3.2
sexpdata==0.0.3
tzlocal==1.5.1

I'll try doing a ~/.emacs.d/.python-environments/default/bin/pip install 'parso!=0.3.2' to see if that fixes it.

[Muldfox]

λ .emacs.d\.python-environments\default\Scripts\activate.bat

λ (default) pip freeze
epc==0.0.5
jedi==0.11.0
jediepcserver==0.2.7
parso==0.1.0
sexpdata==0.0.3

Jedi works fine for me now, and these are the packages in use.

[immerrr]

If downgrading helps, the problem is clearly with the new version of jedi/parso. But I still have hard time reproducing it.

Could you try adding

(setq jedi:server-args `("--log-level=DEBUG"
                         ,(format "--log=%s" (expand-file-name "~/jediepcserver.log"))
                         "--log-traceback"))

to the config and check the $HOME/jediepcserver.log.* files for clues regarding what's happening?

[immerrr]

The "FStringStart"-related error appears to be a common thing among different Jedi "frontends":

• AttributeError: ’FStringStart’ object has no attribute ’children’ palantir/python-language-server#424
• AttributeError: 'FStringStart' object has no attribute 'children' (/pythonx/jedi/jedi/evaluate/syntax_tree.py?) davidhalter/jedi-vim#881