This warning just needs to be traced in one place for all commands,
there's no need for the resolver to know about it. Moving the warning
out of the Resolver will make it easier to change how we provide the
option.
Since wheels can't be editable, we can move this into LinkCandidate,
closer to `RequirementPreparer.prepare_linked_requirement` into which we
want to integrate `_fetch_metadata`.
Instead of an early return, we fall through to the existing check at the
end of this function. This aligns our treatment of `_fetch_metadata` and
`_prepare_distribution`.
Since `_prepare` is called in two places, we preserve the
`if self._dist is not None` protection above the new call to
`_fetch_metadata`. The second `if` in `_prepare` handles the early
return required when processing a lazy wheel.
Now that `_dist` is only set on success, we can use it to guard against
repeated execution instead of `_prepared`. As a result there are now only
two possible outcomes for calling `dist`:
1. `_dist` set and returned - lazy and non-lazy req
2. `_dist` not set and exception raised - bad lazy or bad non-lazy req
Previously a call to `_fetch_metadata` could result in several possible
outcomes:
1. `_dist` set, `_provided` not set, dist returned - for lazy wheels
2. `_dist` set, `_provided` not set, exception - for bad lazy wheels
3. `_dist` not set, `_provided` not set, exception - for non-lazy req
exceptions
4. `_dist` set, `_provided` not set, exception - for bad non-lazy reqs
5. `_dist` set, `_provided` set, dist returned - for non-lazy reqs
and probably more.
Our intent is to use `_dist` being set as the indicator of "this
requirement has been fully processed successfully" and discard
`_prepared`, since we don't actually rely on any of the other states
(they simply lead to a failure or in the future a retry).
This makes it more consistent with how error "summary" lines look.
eg:
IndexError: list index out of range
ModuleNotFoundError: No module named 'notamodule'
Previously:
- the example wildcard version string was being rendered with a stray
space (`== 3.1. *` instead of `== 3.1.*`) due to the markup being
split over two lines
- the "Dependency Hell" Wikipedia URL 404ed due to the trailing `>`
SVN has multiple distributions on Windows, e.g. SlikSVN, CollabNet. Some
of them suffix the version with a "-{distro}" part, which causes the
previous implementation to fail.
This patch removes that final part and make the version logic work.
The previous implementation uses pkg_resources.get_distribution(), which
does not canonicalize the package name correctly, and fails when
combined with pip's own get_distribution(), which does canonicalize
names. This makes InstallRequirement.check_if_exists() only use pip's
own canonicalization logic so different package name forms are matched
as expected.
Originally we would throw an `AttributeError` if a bad scheme key was
used. After refactoring we would throw a `KeyError`, which isn't much
better. Now we call out the wheel being processed, scheme key we didn't
recognize, and provide a list of the valid scheme keys. This would
likely be useful for people developing/testing the wheel.
Previously our wheel installation process allowed wheels which contained
non-conforming contents in a contained .data directory.
After the refactoring to enable direct-from-wheel installation, pip
throws an exception when encountering these wheels, but does not include
any helpful information to pinpoint the cause.
Now if we encounter such a wheel, we trace an error that includes the
name of the requirement we're trying to install, the path to the wheel
file, the path we didn't understand, and a hint about what we expect.
