missing dependency on `bs4`

$ pip install soupsieve
Collecting soupsieve
  Downloading soupsieve-2.3.2.post1-py3-none-any.whl (37 kB)
Installing collected packages: soupsieve
Successfully installed soupsieve-2.3.2.post1
$ python3 -c 'import soupsieve'
Traceback (most recent call last):
  File "<string>", line 1, in <module>
  File "/tmp/y/venv/lib/python3.10/site-packages/soupsieve/__init__.py", line 29, in <module>
    from . import css_parser as cp
  File "/tmp/y/venv/lib/python3.10/site-packages/soupsieve/css_parser.py", line 5, in <module>
    from . import css_match as cm
  File "/tmp/y/venv/lib/python3.10/site-packages/soupsieve/css_match.py", line 7, in <module>
    import bs4  # type: ignore[import]

I understand soupsieve is intended to be used with beautifulsoup but it isn’t even importable without it installed – soupsieve should probably have an install_requires (or whatever the hatch-equivalent is) that include beautifulsoup4

[facelessuser]

As the conversation on this has died out, I will close this with the following comment:

Soup Sieve was originally created to accept BS4 objects/elements and to apply selectors, but the hope was always to replace the official CSS selectors in BS4. Since it has been accepted as the new official CSS selector support in BS4 and is a required dependency of BS4., Soup Sieve can really be viewed as a sub-module of Beautiful Soup as it is not optional and is not useful by itself.

Soup Sieve does offer some optional ways to apply selectors that are not built into Beautiful Soup such as closest, etc. These require you to explicitly import those methods, but Soup Sieve is still considered a part of Beautiful Soup at this point. If BS4 made CSS selectors optional, then, and only then, would we add the BS4 requirement to this package.

[facelessuser]

Just as an FYI, some of the issues related to circular dependencies were installing packages manually: https://github.com/squidfunk/mkdocs-material/discussions/2591. Additionally, there are tools like Pyodide which have to install packages manually. SoupSieve is supported there as well: https://github.com/pyodide/pyodide/tree/main/packages/soupsieve. They would have to add special exceptions to handle this odd, two-way dependency.

I didn’t find the specific example of other package managers, I’m not sure where the original conversation was, but I’m still fairly certain it was an issue at some time in at least one of them.