1739177 - create-mach-environment fails when it cannot form a relative path to site-packages

Status: RESOLVED FIXED

(Firefox Build System :: Mach Core, defect)

Description

[Molly Howell (she/her) (mostly inactive)]

create-mach-environment is failing for me with the following error:

ValueError: path is on mount 'h:', start on mount 'c:'

  File "h:\mozilla\mozilla-central\python/mozbuild/mozbuild/mach_commands.py", line 2481, in create_mach_environment
    manager.build()
  File "h:\mozilla\mozilla-central\python\mach\mach\virtualenv.py", line 325, in build
    f.write("{}\n".format(os.path.relpath(path, site_packages_dir)))
  File "g:\mozilla-build\python3\lib\ntpath.py", line 562, in relpath
    path_drive, start_drive))

virtualenv.py:325 appears to be trying to form a relative path from within the source tree to the virtualenv's site-packages directory, but I have those things on separate drives, so a relative path between them does not exist. This has made me effectively unable to use mach at all.

Comment 1

[Mitchell Hentges [:mhentges] 🦀]

Attachment: Bug 1739177: Add `requirements.pths_as_absolute()`

There were a bunch of locations where we were doing path shenanigans
with requirements.pth/.vendored items.

There was a bit of complexity because we were specifically making each
pthfile line be a relative path to support moving the Firefox
topsrcdir without causing issues.

However, now that we're more intelligent about checking if pthfile
lines are up-to-date (and since moving your topsrcdir will still require
re-generating the Mach virtualenv), this behaviour became less useful.

So, generalize MachEnvRequirements -> "sys.path lines" logic and
reuse it everywhere.

Comment 2

[Mitchell Hentges [:mhentges] 🦀]

Molly can you try moz-phab patch --apply-to=here D129693 and see if it resolves the issue for you?

Comment 3

[Molly Howell (she/her) (mostly inactive)]

That does seem to have done the trick, yeah; everything seems to be working normally now. Thanks for jumping on this so quick!

Comment 4

[Pulsebot]

Pushed by [e-mail]:
https://hg.mozilla.org/integration/autoland/rev/59d1baf2a83f
Add `requirements.pths_as_absolute()` r=ahal

Comment 5

[Cristian Tuns]

https://hg.mozilla.org/mozilla-central/rev/59d1baf2a83f