Emacs 25.1 & Python 3.6.0 Integration [Newbie]

Question

Preface:

I've been dabbling with python programming for a mere few months now. Previously, I spent most of my programming time using C# with Visual Studio. In the Python world, I've been using PyCharm for my projects. It has excellent code-completion (much like the IntelliSense I'm used to) and a nice level of customizability. However, at the end of the day, I want something a little bit lighter and less clunky. I have seen videos of developers using Emacs with Python and I'm quite interested in learning it.

Setup:

• Python 3.6.0 is installed.
• I have downloaded emacs-25.1-x86_64-w64-mingw32.zip from the Emacs website.
• I have created a folder C:\emacs and extracted the zip file to this location
• I have identified the Emacs home folder as C:\Users\joshu\AppData\Roaming\.emacs.d
• I have created an init.el file in this directory since one did not exist

Python Integration:

Now, this is where I'm struggling. I'm still extremely new to the software so it's a bit hard to piece together information from the internet. Using this tutorial I have developed a baseline init.el file. Due to my reputation points, I cannot include a third link here. The Gist containing my init.el file is commented below.

When I open Emacs and open a python file, editing works. However, I'm running into the issues outlined below:

1. C-c C-c returns an error. It seems to be a relatively wide-spread error upon Googling. By simply typing C-c C-c again, the shell will appear with the code being executed; however, it gives me the line python.el: native completion setup failed

Edit: The error is Warning (python): Your ‘python-shell-interpreter’ doesn’t seem to support readline, yet ‘python-shell-completion-native’ was t and "python3" is not part of the ‘python-shell-completion-native-disabled-interpreters’ list. Native completions have been disabled locally.

2. Python autocomplete doesn't seem to be working properly. When using PyCharm, I get a much, much more robust offering of completions. In the case of Emacs, if I begin typing something such as from tkint it will not suggest tkinter. Similarly, if I start typing from math import a it will not suggest abs. I'm not sure at all how to configure Python autocompletion. I've read a few things about using pip install jedi and so on, but I haven't done any of that.

I realize this may be just as much a python question as an Emacs question in some regards. Any insight is appreciated.

Answer 1

This seems to be bug in emacs and its fixed in this commit.

As npostavs mentioned, you can use

(with-eval-after-load 'python
  (defun python-shell-completion-native-try ()
    "Return non-nil if can trigger native completion."
    (let ((python-shell-completion-native-enable t)
          (python-shell-completion-native-output-timeout
           python-shell-completion-native-try-output-timeout))
      (python-shell-completion-native-get-completions
       (get-buffer-process (current-buffer))
       nil "_"))))

You can read entire discussion here.

Answer 2

I use the following:

(setq
 python-shell-interpreter "ipython3"
 python-shell-interpreter-args "--simple-prompt --pprint")

For python 3.6 I found jedi with company to be the most reliable but others may have different experiences. "mypath" below are the paths to packages I've created that I want autocomplete.

(use-package company-jedi      
 :config
  (setq jedi:environment-virtualenv (list (expand-file-name "~/.emacs.d/.python-environments/")))
  (add-hook 'python-mode-hook 'jedi:setup)
  (setq jedi:complete-on-dot t)
  (setq jedi:use-shortcuts t)
  (setq jedi:server-args
  '("--sys-path" "mypath1"
    "--sys-path" "mypath2"))

  (defun config/enable-company-jedi ()
    (add-to-list 'company-backends 'company-jedi))
  (add-hook 'python-mode-hook 'config/enable-company-jedi))

Answer 3

In Ubuntu 16.04, I added python-setuptools in addition to python3-setuptools. Problem disappeared.

(I'm using Emacs 25.3.2, from the stable kelleyk PPA; Spacemacs user)

Answer 4

Regarding programming Python in emacs, be sure to check out LSP. It is a wonderful initiative that is well maintained and supported.