> Spamlib-0.1.dist-info is in a directory on sys.path, so the error makes no sense to me.  Can you inspect the content of that directory?  (i.e os.listdir and file contents)  Also, if you can interrupt the test to get a Python or pdb shell, could you try this:
> 
>   >>> from packaging.database import Distribution
>   >>> d = Distribution('path/to/Spamlib-0.1.dist-info')
>   >>> d.metadata
>   >>> d.list_distinfo_files()
>   >>> d.list_installed_files()

(Pdb) p install_dir
'c:\\users\\nadeem\\appdata\\local\\temp\\tmpe96yhv\\tmp9ga04b'

(Pdb) from packaging.database import Distribution
(Pdb) _d = Distribution(os.path.join(install_dir, "Spamlib-0.1.dist-info"))
(Pdb) p _d
<Distribution 'Spamlib' 0.1 at 'c:\\users\\nadeem\\appdata\\local\\temp\\tmpe96yhv\\tmp9ga04b\\Spamlib-0.1.dist-info'>

(Pdb) p _d.metadata
<packaging.metadata.Metadata object at 0x0351C118>

(Pdb) p dict(_d.metadata.items())
{'Name': 'Spamlib', 'License': 'UNKNOWN', 'Author': 'UNKNOWN', 'Metadata-Version': '1.0',
 'Home-page': 'UNKNOWN', 'Summary': 'UNKNOWN', 'Platform': [], 'Version': '0.1',
 'Keywords': [''], 'Author-email': 'UNKNOWN', 'Description': 'UNKNOWN'}

(Pdb) p list(_d.list_distinfo_files())
['c:\\users\\nadeem\\appdata\\local\\temp\\tmpe96yhv\\tmp9ga04b\\Spamlib-0.1.dist-info\\METADATA',
 'c:\\users\\nadeem\\appdata\\local\\temp\\tmpe96yhv\\tmp9ga04b\\Spamlib-0.1.dist-info\\INSTALLER',
 'c:\\users\\nadeem\\appdata\\local\\temp\\tmpe96yhv\\tmp9ga04b\\Spamlib-0.1.dist-info\\REQUESTED',
 'c:\\users\\nadeem\\appdata\\local\\temp\\tmpe96yhv\\tmp9ga04b\\Spamlib-0.1.dist-info\\RESOURCES',
 'c:\\users\\nadeem\\appdata\\local\\temp\\tmpe96yhv\\tmp9ga04b\\Spamlib-0.1.dist-info\\RECORD']

(Pdb) p list(_d.list_installed_files())
[('c:\\users\\nadeem\\appdata\\local\\temp\\tmpe96yhv\\tmpo8yw3_\\spamd', 'd13e6156ce78919a981e424b2fdcd974', '15'),
 ('c:\\users\\nadeem\\appdata\\local\\temp\\tmpe96yhv\\tmp9ga04b\\Spamlib-0.1.dist-info\\METADATA', '8c9f474663f774563ded42983eb22447', '182'),
 ('c:\\users\\nadeem\\appdata\\local\\temp\\tmpe96yhv\\tmp9ga04b\\Spamlib-0.1.dist-info\\INSTALLER', '44e3fde05f3f537ed85831969acf396d', '9'),
 ('c:\\users\\nadeem\\appdata\\local\\temp\\tmpe96yhv\\tmp9ga04b\\Spamlib-0.1.dist-info\\REQUESTED', 'd41d8cd98f00b204e9800998ecf8427e', '0'),
 ('c:\\users\\nadeem\\appdata\\local\\temp\\tmpe96yhv\\tmp9ga04b\\Spamlib-0.1.dist-info\\RESOURCES', '1c5aec043865966e17b1044e20087b9d', '68'),
 ('c:\\users\\nadeem\\appdata\\local\\temp\\tmpe96yhv\\tmp9ga04b\\Spamlib-0.1.dist-info\\RECORD', '', '')]

==== File contents:

spamd [no EOL]:
    # Python script

METADATA:
    Metadata-Version: 1.0
    Name: Spamlib
    Version: 0.1
    Summary: UNKNOWN
    Description: UNKNOWN
    Keywords: 
    Home-page: UNKNOWN
    Author: UNKNOWN
    Author-email: UNKNOWN
    License: UNKNOWN

INSTALLER [no EOL]:
    distutils

REQUESTED is empty

RESOURCES:
    spamd,c:\users\nadeem\appdata\local\temp\tmpe96yhv\tmpo8yw3_\spamd

RECORD:
    c:\users\nadeem\appdata\local\temp\tmpe96yhv\tmpo8yw3_\spamd,d13e6156ce78919a981e424b2fdcd974,15
    c:\users\nadeem\appdata\local\temp\tmpe96yhv\tmp9ga04b\Spamlib-0.1.dist-info\METADATA,8c9f474663f774563ded42983eb22447,182
    c:\users\nadeem\appdata\local\temp\tmpe96yhv\tmp9ga04b\Spamlib-0.1.dist-info\INSTALLER,44e3fde05f3f537ed85831969acf396d,9
    c:\users\nadeem\appdata\local\temp\tmpe96yhv\tmp9ga04b\Spamlib-0.1.dist-info\REQUESTED,d41d8cd98f00b204e9800998ecf8427e,0
    c:\users\nadeem\appdata\local\temp\tmpe96yhv\tmp9ga04b\Spamlib-0.1.dist-info\RESOURCES,1c5aec043865966e17b1044e20087b9d,68
    c:\users\nadeem\appdata\local\temp\tmpe96yhv\tmp9ga04b\Spamlib-0.1.dist-info\RECORD,,

====

> Where should be the distro?

You won't find it in the hg repository - it gets created by the test, and
then deleted afterwards.

> The changeset was:
> $ hg tip
> changeset:   73075:d4839fea4a5a
> [...]

That's not possible - these failures have been around for over a week now,
and that changeset was only committed yesterday.

From running the tests locally, it looks like test_resources was failing on
Windows since it was first introduced in 1f3459b08298. This didn't show up so
clearly on the buildbots because the build was broken at the time.