Document which environment variables are passed through by default

[jugmac00]

Documentation for tox3 had https://tox.wiki/en/3.27.0/config.html#conf-passenv

Documentation for tox4 does not show the list any more

Also see

tox/src/tox/tox_env/api.py

Lines 179 to 204 in 6b1cc14

	def _default_pass_env(self) -> list[str]:
	env = [
	"https_proxy", # HTTP proxy configuration
	"http_proxy", # HTTP proxy configuration
	"no_proxy", # HTTP proxy configuration
	"LANG", # localization
	"LANGUAGE", # localization
	"CURL_CA_BUNDLE", # curl certificates
	"SSL_CERT_FILE", # https certificates
	"LD_LIBRARY_PATH", # location of libs
	]
	if sys.stdout.isatty(): # if we're on a interactive shell pass on the TERM
	env.append("TERM")
	if sys.platform == "win32": # pragma: win32 cover
	env.extend(
	[
	"TEMP", # temporary file location
	"TMP", # temporary file location
	"USERPROFILE", # needed for `os.path.expanduser()`
	"PATHEXT", # needed for discovering executables
	"MSYSTEM", # controls paths printed format
	],
	)
	else: # pragma: win32 no cover
	env.append("TMPDIR") # temporary file location
	return env

[gaborbernat]

Also:

• https://github.com/tox-dev/tox/blob/main/src/tox/tox_env/python/api.py#L105-L120
• https://github.com/tox-dev/tox/blob/main/src/tox/tox_env/python/virtual_env/api.py#L93-L94

[gaborbernat]

For what's the best documentation is:

tox c -e py -k pass_env 

🤷 rather than some hard-coded list in a webpage that's quickly stale or can be overwritten by your config.

[gaborbernat]

@seyidaniels will try to tackle this :)