Environments created by pypa/virtualenv >=20 can pass both real_prefix
and base_prefix checks, but are only able to use the pyvenv.cfg values,
not the legacy `no-global-site-packages.txt`. So we need to check for
venv (PEP 405) first.
This makes the resolver interface simpler by returning a brand new
RequirementSet vs mutating the one that was input to the function, and
will let us specialize RequirementSet for the different use cases.
Since all directories are now globally-managed, we don't need to be
concerned with resetting the member values.
This will also let us remove several responsibilities from
RequirementSet, which will make integrating the new resolver easier.
Previously we were writing a delete marker file which is checked in
InstallRequirement.remove_temporary_source which is only invoked if the
user did not pass --no-clean (and a PreviousBuildDirError was not
raised). Since our TempDirectory machinery now respects these conditions
we can just wrap our source directory in that instead of using this
ad-hoc mechanism for tracking our delete preference.
This will let us clean up a lot of dead code that only existed for this
use case.
We want to use this value to determine whether a globally-managed
source_dir should delegate choosing deletion to the global tempdir
manager, so it needs to be above our call to
InstallRequirement.ensure_has_source_dir.
Since we need both the file path and content type to unpack, and we want
to move unpacking out of the lower-level functions, return all the
information needed so it's easier to move the unpacking out.
InstallRequirement.remove_temporary_source was already being called at
the end of processing (as part of RequirementSet.cleanup()), so this
doesn't change behavior - cleanup still happens right after the command
finishes.
Now we can refactor this to be globally managed, and it will have the
same behavior as it does currently (if there is any
PreviousBuildDirError it will not be cleaned up).
This mirrors the current logic within the individual requirement-related
commands (install, wheel) for setting options.no_clean, which is used to
determine whether we need to delete directories.
Next, we'll add the actual directories to track and remove them from
being managed by other objects.
InstallRequirement only checks for a delete marker file in source_dir.
Since the result of ensure_build_location is set to source_dir (in
ensure_has_source_dir), and ensure_build_location returns a subdirectory
of the build_directory to which we write the delete marker file, then
this delete marker file is never used.
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.
_should_cache is only called by _get_cache_dir.
In pip install mode, _get_cache_dir is never called when
check_binary_allowed returns False because in that case
should_build_for_install_command has returned False before
and the build was skipped.
In pip wheel mode, check_binary_allowed always returns True
(because it is not passed to the build function).
So _should_cache can use _always_true for check_binary_allowed.
*Alternative*
Alternatively, we could have passed check_binary_allowed
to build in pip wheel mode. The only difference is that wheels built
locally from *legacy* packages would then not be cached,
when pip wheel is used with --no-binary.
This gives us a global toggle that we can use to control whether
temporary directories get deleted from one place (ideally, in the
commands taking --no-clean).
This untested function was only used in one place. Inlining it makes it
easier to see the symmetry between the writing of the delete marker file
in `ensure_build_location` and checking for it in
`remove_temporary_source`.
