PVM

The seamless Python Version Manager for Windows!

by viki

Notes:

Checkout this repo into any path which does not contain a python.exe
Open a Powershell session, run this command to change your Powershell execution policy so that local .ps1 file can be executed:

Set-ExecutionPolicy RemoteSigned
Make sure the .ps1 file is associated with Powershell.exe. Use "Open with ..." menu to change it if it isn't.
Add .ps1 into your System Environment Variable PATHEXT. So we can execute python.ps1 file after initialization, without typing extension ".ps1".

$ echo %PATHEXT%

.COM;.EXE;.BAT;.CMD;.VBS;.VBE;.JS;.JSE;.WSF;.WSH;.MSC;.PS1

Double-click on this python.ps1 to run the automatic configuration initialization. If you get a python REPL, it's done.

Remove the 'python' alias in user's Env:Path
This script is not in Env:Path. Initialize the configuration.
Scan for existing python ...
Try to execute 'python', please ignore the error messages below this line ...
Found existing Python path: D:\Python37-64\python.exe
Found existing Python version:  3.7.6
Python root is D:\Python37-64
Remove this python from Machine Env:Path
Remove this python from User Env:Path
Try to execute 'python', please ignore the error messages below this line ...
Found existing Python path: D:\Python383-64\python.exe
Found existing Python version:  3.8.3
Python root is D:\Python383-64
Remove this python from Machine Env:Path
Remove this python from User Env:Path
Try to execute 'python', please ignore the error messages below this line ...
无法将“python”项识别为 cmdlet、函数、脚本文件或可运行程序的名称。请检查名称的拼写，如果包括路径，请确保路径正确，然后
再试一次。
   + CategoryInfo          : ObjectNotFound: (python:String) [], CommandNotFoundException
   + FullyQualifiedErrorId : CommandNotFoundException
   + PSComputerName        : localhost

无法将“python”项识别为 cmdlet、函数、脚本文件或可运行程序的名称。请检查名称的拼写，如果包括路径，请确保路径正确，然后
再试一次。
   + CategoryInfo          : ObjectNotFound: (python:String) [], CommandNotFoundException
   + FullyQualifiedErrorId : CommandNotFoundException
   + PSComputerName        : localhost

OK. No python in Env:Path any more. Just ignore error messages above this line.
All found python have been configurated.
Load configuration ...
Merge found python and configurated python ...
$PVM_REQUIRED_VER is
Manipulated arguments:
Selected version = 3
Try use python in D:\Python383-64 to execute: python
Python 3.8.3 (tags/v3.8.3:6f8c832, May 13 2020, 22:37:02) [MSC v.1924 64 bit (AMD64)] on win32
Type "help", "copyright", "credits" or "license" for more information.
>>>

All of your python versions found in Env::Path are configurated now. You can found the configuration file in

C:\Users\<UserName>\pvm.json

{
   "timestamp":  "2020-06-23 14:25:35Z",
   "last_version":  "3",
   "versions": {
      "3.8.3":  {
         "virtual":  0,
         "path":  "D:\\Python383-64",
         "home":  "D:\\Python383-644"
      },
      "383":  {
         "virtual":  0,
         "path":  "D:\\Python383-64",
         "home":  "D:\\Python383-64"
      },
      "3.7.6":  {
         "virtual":  0,
         "path":  "D:\\Python37-64",
         "home":  "D:\\python37-64"
      },
      "376":  {
         "virtual":  0,
         "path":  "D:\\Python37-64",
         "home":  "D:\\python37-64"
      },
      "3":  {
         "virtual":  0,
         "path":  "D:\\Python383-64",
         "home":  "D:\\Python383-64"
      },
      "swiftnet37":  {
         "virtual":  1,
         "path":  "D:\\pyenvs\\swiftnet37",
         "home":  "D:\\python37-64"
      },
      "dbdev":  {
         "virtual":  1,
         "path":  "D:\\pyenvs\\dbdev",
         "home":  "D:\\Python37-64"
      }
   }
}

Feel free to edit this file to add/remove/rename python versions. Key of version can be any string. e.g. "old", "conda", etc.

{
   "timestamp":  "2020-06-23 14:25:35Z",
   "last_version":  "3",
   "versions": {
      "old":  {
         "virtual":  0,
         "path":  "D:\\Python2718",
         "home":  "D:\\Python2718"
      },
      "2.7.18":  {
         "virtual":  0,
         "path":  "D:\\Python2718",
         "home":  "D:\\Python2718"
      },
      "conda":  {
         "virtual":  0,
         "path":  "D:\\Python3",
         "home":  "D:\\Python3"
      },
      "3.8.3":  {
         "virtual":  0,
         "path":  "D:\\Python383-64",
         "home":  "D:\\Python383-644"
      },
      "383":  {
         "virtual":  0,
         "path":  "D:\\Python383-64",
         "home":  "D:\\Python383-64"
      },
      "3.7.6":  {
         "virtual":  0,
         "path":  "D:\\Python37-64",
         "home":  "D:\\python37-64"
      },
      "376":  {
         "virtual":  0,
         "path":  "D:\\Python37-64",
         "home":  "D:\\python37-64"
      },
      "3":  {
         "virtual":  0,
         "path":  "D:\\Python383-64",
         "home":  "D:\\Python383-64"
      },
      "swiftnet37":  {
         "virtual":  1,
         "path":  "D:\\pyenvs\\swiftnet37",
         "home":  "D:\\python37-64"
      },
      "dbdev":  {
         "virtual":  1,
         "path":  "D:\\pyenvs\\dbdev",
         "home":  "D:\\Python37-64"
      }
   }
}

From now on, you can specify version to the python commands like (-<version_number> or :<version_name>):

python -3.8.3 example.py

python -2.7.18 example.py

python :374 example.py

python :old example.py

And you can use it without version hint so that it will use the last (or the default) vesion automatically.
Now pvm scans virtual environments (Env:WORKON_HOME). The version_name can be virtualenv name.

python -mynlpenv example.py

workon mynlpenv

'workon' will keep the activated python env in console just like how virtualenv workon works.

But virtual envs created after the initialization will not be added into PVM configuration automatically (We don't want to scan the venv dirs every time). So you can add your virtual envs into configuration by hand.

windviki/pvm

PVM

Notes: