Tox 4.0.x does not support --no-deps dependency spec

[Zac-HD]

With tox 4.0.3 and tox 4.0.5, on WSL locally and on Ubuntu in GitHub Actions, I've noticed that passing --no-deps is now an error:

[tox]
[testenv]
deps =
    # Really useful to check that a requirements file is complete in each environment
    # (e.g. to check pip-compile hasn't left any deps unpinned on some versions or OSes)
    --no-deps  # works if you comment out this line
    urllib3    # just a common dep, for simplicity
commands =
    python -c 'print("Hello World!")'

$ tox  # 4.0.5, on Python 3.8, WSL

py: internal error
Traceback (most recent call last):
  File "tox/tox_env/python/pip/pip_install.py", line 93, in _install_requirement_file
    new_options, new_reqs = arguments.unroll()
  File "tox/tox_env/python/pip/req_file.py", line 84, in unroll   
    opts_dict = vars(self.options)
  File "tox/tox_env/python/pip/req/file.py", line 153, in options 
    self._ensure_requirements_parsed()
  File "tox/tox_env/python/pip/req/file.py", line 169, in _ensure_requirements_parsed
    self._requirements = self._parse_requirements(opt=self._opt, recurse=True)
  File "tox/tox_env/python/pip/req_file.py", line 71, in _parse_requirements
    requirements = super()._parse_requirements(opt, recurse)
  File "tox/tox_env/python/pip/req/file.py", line 173, in _parse_requirements
    for parsed_line in self._parse_and_recurse(str(self._path), self.is_constraint, recurse):
  File "tox/tox_env/python/pip/req/file.py", line 195, in _parse_and_recurse
    for line in self._parse_file(filename, constraint):
  File "tox/tox_env/python/pip/req/file.py", line 217, in _parse_file
    args_str, opts = self._parse_line(line)
  File "tox/tox_env/python/pip/req/file.py", line 264, in _parse_line
    opts = self._parser.parse_args(args)
  File "/usr/lib/python3.8/argparse.py", line 1783, in parse_args
    self.error(msg % ' '.join(argv))
  File "/usr/lib/python3.8/argparse.py", line 2533, in error
    self.exit(2, _('%(prog)s: error: %(message)s\n') % args)
  File "tox/tox_env/python/pip/req/args.py", line 18, in exit     
    raise ValueError(msg)
ValueError: unrecognized arguments: --no-deps

During handling of the above exception, another exception occurred:

Traceback (most recent call last):
  File "tox/session/cmd/run/single.py", line 45, in _evaluate     
    tox_env.setup()
  File "tox/tox_env/api.py", line 226, in setup
    self._setup_env()
  File "tox/tox_env/python/runner.py", line 99, in _setup_env     
    self._install_deps()
  File "tox/tox_env/python/runner.py", line 103, in _install_deps 
    self.installer.install(requirements_file, PythonRun.__name__, "deps")
  File "tox/tox_env/python/pip/pip_install.py", line 84, in install
    self._install_requirement_file(arguments, section, of_type)
  File "tox/tox_env/python/pip/pip_install.py", line 95, in _install_requirement_file
    raise HandledError(f"{exception} for tox env py within deps")
tox.report.HandledError: unrecognized arguments: --no-deps for tox env py within deps
  py: FAIL code 2 (4.17 seconds)
  evaluation failed :( (19.80 seconds)

[gaborbernat]

What's the use case for this flag? Do you have a reproducible on a demo project? Pull requests welcome.

[Zac-HD]

I use this on every project where I use pip-tools to compile my requirements files, to ensure that I've correctly specified any version- or platform-specific requirements. It's also very useful in restricted corporate environments, to ensure that dependency resolution doesn't pull in a package which isn't explicitly allowlisted.

I constructed the above example based on this failing build in shed, but most of my other projects use the same pattern and I'm pretty sure I got the idea from someone else, though I don't remember where.

[gaborbernat]

Seems this is not supported as part of the requirements.txt, so really the only use of it part of the CLI 🤔

❯ venv/bin/pip install -r requirements.txt
Usage: pip [options]

ERROR: Invalid requirement: --no-deps
pip: error: no such option: --no-deps

~/git/github/tox/magic on  main [!]
❯ virtualenv venv^C
~/git/github/tox/magic on  main [!]
❯ cat requirements.txt
--no-deps
urllib3⏎  

The question then is if this should be supported via a separate configuration argument or if it should be only part of deps as was in v3. Note this was not supported in v3, just happened to work 🤔

[gaborbernat]

@Zac-HD this now is out via 4.0.7

[nsoranzo]

@gaborbernat This seems to have introduced a regression, see https://github.com/galaxyproject/galaxy/actions/runs/3670306804/jobs/6204749384

lint: internal error
Traceback (most recent call last):
  File "/opt/hostedtoolcache/Python/3.9.15/x64/lib/python3.9/site-packages/tox/session/cmd/run/single.py", line 45, in _evaluate
    tox_env.setup()
  File "/opt/hostedtoolcache/Python/3.9.15/x64/lib/python3.9/site-packages/tox/tox_env/api.py", line 236, in setup
    self._setup_env()
  File "/opt/hostedtoolcache/Python/3.9.15/x64/lib/python3.9/site-packages/tox/tox_env/python/runner.py", line 99, in _setup_env
    self._install_deps()
  File "/opt/hostedtoolcache/Python/3.9.15/x64/lib/python3.9/site-packages/tox/tox_env/python/runner.py", line 103, in _install_deps
    self.installer.install(requirements_file, PythonRun.__name__, "deps")
  File "/opt/hostedtoolcache/Python/3.9.15/x64/lib/python3.9/site-packages/tox/tox_env/python/pip/pip_install.py", line 83, in install
    self._install_requirement_file(arguments, section, of_type)
  File "/opt/hostedtoolcache/Python/3.9.15/x64/lib/python3.9/site-packages/tox/tox_env/python/pip/pip_install.py", line 92, in _install_requirement_file
    new_options, new_reqs = arguments.unroll()
  File "/opt/hostedtoolcache/Python/3.9.15/x64/lib/python3.9/site-packages/tox/tox_env/python/pip/req_file.py", line 104, in unroll
    opts_dict = vars(self.options)
  File "/opt/hostedtoolcache/Python/3.9.15/x64/lib/python3.9/site-packages/tox/tox_env/python/pip/req/file.py", line 157, in options
    self._ensure_requirements_parsed()
  File "/opt/hostedtoolcache/Python/3.9.15/x64/lib/python3.9/site-packages/tox/tox_env/python/pip/req/file.py", line 177, in _ensure_requirements_parsed
    self._requirements = self._parse_requirements(opt=self._opt, recurse=True)
  File "/opt/hostedtoolcache/Python/3.9.15/x64/lib/python3.9/site-packages/tox/tox_env/python/pip/req_file.py", line 92, in _parse_requirements
    requirements = super()._parse_requirements(opt, recurse)
  File "/opt/hostedtoolcache/Python/3.9.15/x64/lib/python3.9/site-packages/tox/tox_env/python/pip/req/file.py", line 189, in _parse_requirements
    self._merge_option_line(opt, parsed_line.opts, parsed_line.filename)
  File "/opt/hostedtoolcache/Python/3.9.15/x64/lib/python3.9/site-packages/tox/tox_env/python/pip/req_file.py", line 26, in _merge_option_line
    if opt.no_deps:
AttributeError: 'Namespace' object has no attribute 'no_deps'
  lint: FAIL code 2 (0.28 seconds)
  evaluation failed :( (0.41 seconds)

[gaborbernat]

@nsoranzo https://github.com/tox-dev/tox/releases/tag/4.0.8

[nsoranzo]

@gaborbernat Great, thanks, that was super-fast. Tested and looks fixed!