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This is not a flaky works half the time kind of plugin, it's a seriously smooth editing experience. I've just started using pyflyby, and it is solid so far. I have automatic imports on every save of a python file in neovim, and automatic imports on every command in ipython.
I can't tell you how pumped I am for this, and how good its felt to use over the past few weeks. It's glorious.
YouTube video
Listen to me rant on how great pyflyby is
Give the video a watch, I did not have noise-cancelling on in obs. My apologies for the background hum and the mic stand bumps. I did my best to fix them up.
Installation
How to install pyflyby for automatic python imports
pyflyby is hosted on pypi, so you can get it with pip. I have had no issues installing it on 3.8+ so far.
pip install pyflyby
Configuration setup with stow
always stow your dotfiles
If you're going to configure any of your tools the first thing you should do is set it up with stow, seriously don't sleep on the stow. If you don't have stow installed or choose not to use stow you can skip this part.
cd ~/dotfiles mkdir ipython touch ipython/.pyflyby stow ipython
Seriously don't sleep on the stow.
How to Configure pyflyby
it's just a file full of import statements
pyflyby is configured simply by putting all of your import statements that you
want to automatically import into your ~/.pyflyby file. You can import pandas, from pandas import DataFrame, or even import pandas as pd, and all
of these will work pretty much as expected.
# comments start with a # # import your favorite libraries import visidata as vd import fsspec import difflib import s3fs import seaborn as sns import plotly # also supports from imports from rich.layout import Layout from rich.live import Live # duplicates are allowed import plotly import plotly # duplicate names from different libraries are not allowed import copy from numpy import copy
Add all the things you would like to be imported automatically, just as you would import them. I went kinda crazy and added over 200 to mine based on packages that I use.
Commas are even supported
yep all the import styles are supported
This following example will set up auto import for both DataFrame and Series, they will both work separately. I removed these from my config as I felt it was cleaner without, but it works with them.
from pandas import DataFrame, Series
Even imports with a comma will be treated separately.
Jupyter note
Both work the same, use what your comfortable with
I only really mention ipython here, but the same all applies to Jupyter as well. I just really like ipython itself, c'mon its right there in the terminal integrating with the rest of your terminal experience so well.
Ipython setup
Automatically import python libraries in ipython with pyflyby
The recommended way to set uppyflybyfrom the docs is to run the following magic command. This works well, but I want even less typing, I want pyflyby automatically installed and importing things without me even thinking about it.
%load_ext pyflyby
Ipython setup next level
automatically import modules in python without %load_ext
I really want pyflyby to just work in every environment without me thinking much about it. I want it to load automatically, and even to attempt to install itself if it's missing.
from IPython import get_ipython import subprocess ipython = get_ipython() try: ipython.magic("load_ext pyflyby") except ModuleNotFoundError: print("installing pyflyby") subprocess.Popen( ["pip", "install", "pyflyby"], stdout=subprocess.DEVNULL, stderr=subprocess.DEVNULL, ).wait() ipython.magic("load_ext pyflyby")
Note: if installation fails you will still make it into ipython, there will just be a traceback to the failed command as you enter.
I've had zero issues with this, but if there ever comes a time when it does not work in certain environments for you. I'd strongly suggest you to add this to a separate profile.
Check out this article for a bit more in depth ipython configuration
ipython auto import examples
pyflyby can import all the various import types just fine.
- import something
- from module import something
- import something as alias
df = pd.read_csv("https://waylonwalker.com/cars.csv") [PYFLYBY] import pandas as pd
Getting Help
Want help on something that you have in your pyflyby config, just give it the
?, ??, or help and pyflyby will import it for you.
Popen?
Autocomplete
This is next level python auto-import
pyflyby even goes as far as helping tab completion. If you try to tab complete
Pop it will complete to Popen without even adding Popen to your local
namespace. If you ask for something inside of a module i.e. requests.<tab>,
then it will import requests.
# does not populate the namespace Pop<tab> # !!does populate the local namespace requests.<tab>
What happens when a module is not installed
ModuleNotFoundError
When you are in an environment where you do not have a module installed that is
in your pyflyby config, it will throw a ModuleNotFoundError when it tries to
import, and it will not import or try to install for you. You will have to
change environments or install that module.
❯ pd? [PYFLYBY] import pandas as pd [PYFLYBY] Error attempting to 'import pandas as pd': ModuleNotFoundError: No module named 'pandas' [PYFLYBY] Traceback (most recent call last): [PYFLYBY] File "/home/u_walkews/.local/lib/python3.8/site-packages/pyflyby/_autoimp.py", line 1610, in _try_import [PYFLYBY] exec_(stmt, scratch_namespace) [PYFLYBY] File "<string>", line 1, in <module> [PYFLYBY] ModuleNotFoundError: No module named 'pandas' Object `pd` not found. ❯ df = pd.read_csv("https://waylonwalker.com/cars.csv") <ipython-input-3-69b040434562>:1 in <module> NameError: name 'pd' is not defined
nvim pyflyby setup
automatically importing python modules in vim, neovim, nvim
This is by far the best part of this article. It makes development so fluid. It's not necessarily all about the speed. It really helps you move at the speed of your thoughts, without needing to worry about imports. Remembering where deeply nested modules are does not need to be a thing.
function! s:PyPreSave() Black endfunction function! s:PyPostSave() execute "silent !tidy-imports --black --quiet --replace-star-imports --action REPLACE " . bufname("%") execute "e" endfunction :command! PyPreSave :call s:PyPreSave() :command! PyPostSave :call s:PyPostSave() augroup waylonwalker autocmd! autocmd bufwritepre *.py execute 'PyPreSave' autocmd bufwritepost *.py execute 'PyPostSave' autocmd bufwritepost .tmux.conf execute ':!tmux source-file %' autocmd bufwritepost .tmux.local.conf execute ':!tmux source-file %' autocmd bufwritepost *.vim execute ':source %' augroup end
refactoring
This is where it really shines
This setup really shines when you are refactoring. You can freely move modules and classes around without worrying about bringing imports with them. Often when refactoring some modules from one file to another the most tedious part is editing the imports. Often you can't even grab whole lines because there are several imports and some are needed in both places but not all. pyflyby handles all this like a champ.
Where to install for vim
just make sure the tidy-imports command is available to vim
pyflyby goes into the environment that you have active at the time that you start neovim. Typically, this is the virtual environment that I am using for the project I am editing.
What gets imported/removed
only give me what I actually use
Anything within the base config of pyflyby or your own config specified in
~/.pyflyby will get automatically imported if it is used within the
file/console. If you are working in a file, and stop using a module, it will
automatically get removed.
- Anything that is used, and found in the config is added
- Anything that is unused gets removed
Where does it put imports
after the last import
pyflyby does not sort imports into paragraphs or by category. When it needs
to add new imports. It will find the last paragraph of imports in your file,
add the new one, and sort that paragraph alphabetically.
from collections import Counter import requests from plugins.custom_seo import post_render # <-- pyflyby will put the import here
What about isort
put those imports where they go
I did not like that I was getting pre-commit issues when using pyflyby, so I added isort to my chain of autocommands to automatically run isort and make my pre-commit happy.
function! s:PyPostSave() execute "silent !tidy-imports --black --quiet --replace-star-imports --action REPLACE " . bufname("%") execute "silent !isort " . bufname("%") execute "e" endfunction
Let's write some code
def get(): """ Get all the posts from waylonwalker.com. Yes theres an rss feed, you should be subscribed if your not already. Oh, and we don't need no stinkin error handing because it's always live """ r = requests.get("https://waylonwalker.com/rss.xml") return r.content
Save it and pyflyby will inject requests into our file automatically, no need to type that out anymore.
import requests def get(): """ Get all the posts from waylonwalker.com. Yes theres an rss feed, you should be subscribed if your not already. Oh, and we don't need no stinkin error handing because it's always live """ r = requests.get("https://waylonwalker.com/rss.xml") return r.content
What about init / api's
careful to fill in the __all__ like you are supposed to
Files such as init.py often import things they do not need, this is simply
there for a convenience of the library user and to make the api cleaner. These
type of modules should implement a __all__ list of all the unused things that
are imported according to pep8. Pyflyby will remove any unused modules unless
they are in the __all__ list.
# snippet from kedro.extras.datasets.pandas __all__ = [ "CSVDataSet", "ExcelDataSet", "FeatherDataSet", "GBQTableDataSet", "ExcelDataSet", "AppendableExcelDataSet", "HDFDataSet", "JSONDataSet", "ParquetDataSet", "SQLQueryDataSet", "SQLTableDataSet", ]
py command
one liners that need imports
pyflyby also comes with a cli command to run one liners. It's pretty genius, I'm sure I will find a use or two for it, but so far it's been more of a novelty for me.
py help pd py help pd.DataFrame py pd.read_csv 'https://waylonwalker.com/cars.csv'
