When using python's built-in venv activaton script
warnings are printed when hashing is disabled in
bash or zsh, like;
`bash: hash: hashing disabled`
This output is not really useful to the end-user and has
been disabled in `virtualenv` for long.
This commit is based on:
28e85bcd80
Before, running deactivate from a bash shell configured to treat undefined variables as errors (`set -u`) would produce a warning:
```
$ python3 -m venv test
$ source test/bin/activate
(test) $ deactivate
-bash: $1: unbound variable
```
The activation scripts generated by venv were inconsistent in how they changed the shell's prompt. Some used `__VENV_PROMPT__` exclusively, some used `__VENV_PROMPT__` if it was set even though by default `__VENV_PROMPT__` is always set and the fallback matched the default, and one ignored `__VENV_PROMPT__` and used `__VENV_NAME__` instead (and even used a differing format to the default prompt). This change now has all activation scripts use `__VENV_PROMPT__` only and relies on the fact that venv sets that value by default.
The color of the customization is also now set in fish to the blue from the Python logo for as hex color support is built into that shell (much like PowerShell where the built-in green color is used).
- Remove use of replacement text in the script
- Make use of the pyvenv.cfg file for prompt value.
- Add parameters to allow more flexibility
- Make use of the current path, and assumptions about where env puts things, to compensate
- Make the script a bit more 'idiomatic' Powershell
- Add script documentation (Get-Help .\.venv\Scripts\Activate.ps1 shows PS help page now
Handle Unicode contents on localised Windows systems when activating a
venv. activate.bat currently breaks on German Windows systems, as chcp.com does
not return a plain number as on English systems, but (arbitrarily) appends a dot at the end
(for example "Aktive Codepage: 850." instead of "Active Codepage: 850"). The
dependency to chcp.com is removed and ctypes is used to get, set and restore the
console output code page. The code page for console input is not changed.
We can't use __VENV_PYTHON__ to find python.exe, since it's UTF-8. cmd.exe decodes
the script using the console output code page.
PowerShell Core 6.1 is the cross-platform port of Windows PowerShell. This change updates Activate.ps1 to not make Windows assumptions as well as installing it into the bin/Scripts directory on all operating systems.
Requires PowerShell Core 6.1 for proper readline support once the shell has been activated for the virtual environment.
