Error '[defx] defx requires Python3 support("+python3")' on Windows10, Vim8

Warning: I will close the issue without the minimal init.vim and the reproduction instructions.

Problems summary

I’m getting this error on :Defx command run:

[defx] defx requires Python3 support("+python3").

Vim is compiled with Python3, pynvim is installed. It works fine on NeoVim.

Expected

Vim8 should be able to run :Defx.

Environment Information

• defx version(SHA1): commit SHA-1: 0a42be58745b2b0a19f6d59ca6238d1dfc96a07b

• OS: Win10 x64

• neovim/Vim version: VIM - Vi IMproved 8.1 (2018 May 18, compiled Oct 29 2019 23:02:14)

• :checkhealth or :CheckHealth result(neovim only):

Provide a minimal init.vim/vimrc with less than 50 lines (Required!)

let g:python3_host_prog = '~\AppData\Local\Programs\Python\Python38\python.exe'

call plug#begin('~/.vim-plug')
	Plug 'Shougo/defx.nvim'
	Plug 'roxma/nvim-yarp'
	Plug 'roxma/vim-hug-neovim-rpc'
call plug#end()

The reproduce ways from neovim/Vim starting (Required!)

1. Start Vim8
2. Run :Defx
3. Get error

Screen shot (if possible)

Upload the log file

vimLog.txt

[Shougo]

OK. The problem is fixed.

[EtiamNullam]

You’re right, thanks for clarification. I’ve misinterpreted +python3/dyn assumed it was as good as +python3.

I guess I was fooled a bit by this (https://github.com/roxma/nvim-yarp#requirements):

g:python3_host_prog pointed to your python3 executable [...]

When it seems like g:python3_host_prog is mainly used in nvim. On Vim8 I had to use these two:

set pythonthreehome=~\AppData\Local\Programs\Python\Python38
set pythonthreedll=~\AppData\Local\Programs\Python\Python38\python38.dll

Actually I still had to set g:python3_host_prog for https://github.com/roxma/nvim-yarp.

I’ve ran into two minor issues after that, but that’s my final, working, minimal rc (Vim8):

set encoding=utf-8

let g:python3_host_prog = expand('~\AppData\Local\Programs\Python\Python38\python.exe')

set pythonthreehome=~\AppData\Local\Programs\Python\Python38
set pythonthreedll=~\AppData\Local\Programs\Python\Python38\python38.dll

call plug#begin('~/.vim-plug')
	Plug 'Shougo/defx.nvim'
	Plug 'roxma/nvim-yarp'
	Plug 'roxma/vim-hug-neovim-rpc'
call plug#end()

Sorry for taking your time.