MatchSpec parses incorrectly when channel is passes as a URL

[travishathaway]

What happened?

While using the py-rattler library, I discovered a possible problem with how MatchSpecs are parsed when passing the channel name as a URL

>>> from rattler import MatchSpec
>>> m = MatchSpec("https://conda.anaconda.org/conda-forge::python[version=3.9]")
>>> m
MatchSpec("*")
>>> print(m.channel)
None

The following happens when specifying the channel as a MatchSpec key:

>>> from rattler import MatchSpec
>>> m = MatchSpec("python[channel=https://conda.anaconda.org/conda-forge,version=3.9]")
InvalidMatchSpecException                 Traceback (most recent call last)
Cell In[21], line 1
----> 1 m = MatchSpec("python[channel=https://conda.anaconda.org/python/conda,version=3.9]")

File ~/opt/testminiconda/envs/pyrattler/lib/python3.12/site-packages/rattler/match_spec/match_spec.py:85, in MatchSpec.__init__(self, spec, strict)
     83 def __init__(self, spec: str, strict: bool = False) -> None:
     84     if isinstance(spec, str):
---> 85         self._match_spec = PyMatchSpec(spec, strict)
     86     else:
     87         raise TypeError(
     88             "MatchSpec constructor received unsupported type" f" {type(spec).__name__!r} for the 'spec' parameter"
     89         )

InvalidMatchSpecException: invalid bracket key: channel

What should happen?

I would expect rattler to be able to parse full URLs properly. This is currently also a bug in conda as reported here:

• channel_alias is incorrectly applied to URL conda#14074

But, micromamba appears to be parsing this correctly.

[ruben-arts]

Just to verify. The channel name of https://software.repos.intel.com/python/conda should be conda right? Not python/conda.

EDIT: That was wrong it needs to be python/conda

[baszalmstra]

We just merged #792 which fixes:

>>> from rattler import MatchSpec
>>> m = MatchSpec("https://conda.anaconda.org/conda-forge::python[version=3.9]")
>>> m
MatchSpec("conda-forge::python ==3.9")
>>> m.channel
Channel(name="conda-forge", base_url="https://conda.anaconda.org/conda-forge/")

Parsing python[channel=https://conda.anaconda.org/python/conda,version=3.9] still fails because we dont recognize the channel key yet. That will be next.