When there is a pyproject.toml, metadata preparation must be
done in the isolated build environment for legacy editable installs too
(fixes a regression).
Also detect earlier if an editable install must go through the
legacy install path, to be sure to run it in an environment
with the correct build requirements.
InstallRequirement.satisfied_by is an old-style distribution object
(pkg_resources) for now, so we need to provide a shim for its access in
InstalledDistribution.get_metadata_distribution(). Not sure why this was
not picked up by the type checker :/
The typing module has been available since Python 3.5. Guarding the
import has been unnecessary since dropping Python 2.
Some guards remain to either:
- Avoid circular imports
- Importing objects that are also guarded by typing.TYPE_CHECKING
- Avoid mypy_extensions dependency
The stdlib module has been available since Python 3.5 and the
TYPE_CHECKING constant has been available since 3.5.2.
By using stdlib, this removes the need for pip to maintain its own
Python 2 typing compatibility shim.
Use pyupgrade to convert simple string formatting to use f-string
syntax. pyupgrade is intentionally timid and will not create an f-string
if it would make the expression longer or if the substitution parameters
are anything but simple names or dotted names.
Certain environments seem to be leaving behind empty folders in this
directory -- There was an older pip release that included a source/
folder here which isn't getting deleted for some reason. I have not
figured out the root cause why this happens yet. This is resulting in
ImportErrors since Python imports have a higher precedence for packages
compared to modules.
This commit changes the name we're trying to import from, which should
help prevent this mode of failure.
We now extract all metadata files from the wheel directly into memory
and make them available to the wrapping pkg_resources.Distribution via
the DictMetadata introduced earlier.
Why: Based on some more experience from refactoring metadata generation,
it became clear to me that the separation of legacy vs modern codepaths
should happen at lower level than this abstraction.
Also, create a new utility function for showing a spinner when running
a subprocess.
Why: The subprocess_runner API was specifically added to make it
possible for pip to stop monkey-patching Pep517HookCaller, while still
maintaining its output style. The relevant monkeypatch will be removed
in a follow up commit.
This moves the DistAbstraction logic into a dedicated 'distributions'
sub-package, with separated modules for the concrete implementations of
various distribution handling logic.
