Bug 263589 – [AutoInstall] Handle namespaces packages

• Status: NEW
• Component: Tools / Tests

[Jonathan Bedard]

Currently, AutoInstall does not handle namespace packages (as documented by Python here https://packaging.python.org/en/latest/guides/packaging-namespace-packages/) well. This is because AutoInstall expects the package name to be a folder, and deletes the entire folder when uninstalling a package. This means that AutoInstall can't handle using two namespace packages which share a common parent package. Although we've been able to work around this issue with `aliases` so far, we should have autoinstall correctly handle this situation.

[Radar WebKit Bug Importer]

<rdar://problem/117742039>

[Sam Sneddon [:gsnedders]]

https://commits.webkit.org/230559@main added aliases in the form of:

AutoInstall.register(Package('logilab.common', Version(0, 58, 1), pypi_name='logilab-common', aliases=['logilab']))
AutoInstall.register(Package('logilab.astng', Version(0, 24, 1), pypi_name='logilab-astng', aliases=['logilab']))
AutoInstall.register(Package('zope.interface', Version(5, 1, 0), aliases=['zope'], pypi_name='zope-interface'))

Looking at the first two, given they are the two with the same alias, they both install:

logilab/__init__.py,sha256=BoTPhN0fnF0LnrjGUZovSHBQUocVZx9TupGxudXvSvg,155

…which will, of course, work fine, even if we overwrite it.

We do also delete the directory we believe we're installing into, which for logilab.common is autoinstalled_dir/logilab/common, but we don't actually verify that we only install into that directory.

However, https://commits.webkit.org/228060@main added support for wheels in a way that is significantly more broken with namespace packages:

When we install a wheel, we look at what top-level directories we find within the wheel, and if they already exist, we delete them. This means that if logilab.common had installed logilab/common, and then logilab.astng got installed, we'd delete logilab/ before proceeding to install it.

Really what we should do better at is uninstalling old versions of packages before installing new ones, but maybe in the short-term we should hack around this by making the behaviour the same regardless of whether we're using the legacy dist/setuptools install or installing from a wheel?

[Sam Sneddon [:gsnedders]]

Bug 263392 is about deleting things, which is probably the majority of the problem here?