Add `fawltydeps` (dependency checker) as a linter.

[samcunliffe]

Is Your Feature Request Related to a Problem? Please Describe

In FOSDEM I saw a talk by the developers of fawltydeps which was quite compelling: they argue that software reproducibility is in "crisis". I.e. dependencies are missing or unneeded in many codebases. They angled it to data science software, but I guess that == research software for these purposes.

Describe the Solution You'd Like

I propse to add this as a 🟢 tool to linters table and the template's linters.

Describe Alternatives You've Considered

AFAIK there are no other tools that do this (yet...?) 👀 .

Additional Context

• Talk at FOSDEM
• Getting started docs

Publicity terminal-cast:

[paddyroddy]

Running on this repo:

ERROR:fawltydeps.extract_deps.pyproject_toml_parser:Failed to parse {{cookiecutter.project_slug}}/pyproject.toml: Invalid initial character for a key part (at line 16, column 6)

These imports appear to be undeclared dependencies:
- 'pytest_venv'

These dependencies appear to be unused (i.e. not imported):
- 'build'
- 'mkdocs'
- 'mkdocs-include-markdown-plugin'
- 'mkdocs-material'
- 'mkdocstrings'
- 'mkdocstrings-python'
- 'pytest-cov'

For a more verbose report re-run with the `--detailed` option.

Running on a generated project from the cookiecutter

These dependencies appear to be unused (i.e. not imported):
- 'build'
- 'mkdocs'
- 'mkdocs-include-markdown-plugin'
- 'mkdocs-material'
- 'mkdocstrings'
- 'mkdocstrings-python'
- 'pytest-cov'

For a more verbose report re-run with the `--detailed` option.

Can it be configured? Like the mkdocs stuff is being used...

[samcunliffe]

Oh interesting. Yes, we can configure it, plus they are responsive to feature requests. pytest-cov will be fixed in version 1 (+ pytest_venv at a guess) and we'll also be able to add a mkdocks-* wildcard to the ignore lists.