Functional tests fail in WSL Ubuntu

[nathanjcollins]

Describe the bug

Using home-manager switch and flakes, the nix functional tests fail with:

Steps To Reproduce

Run home-manager switch --flake .#x86_64-linux --extra-experimental-features 'nix-command flakes' --impure (I'm using impure to allow nonfree) and the tests fail as so:

error: builder for '/nix/store/7sf9wzlhvpfvplm733layngqaq5xrcc0-nix-functional-tests-2.30pre20250521_76a4d4c2.drv' failed with exit code 2;
       last 25 log lines:
       > 180/193 nix-functional-tests:git-hashing / simple                                    OK              0.91s
       > 181/193 nix-functional-tests:local-overlay-store / check-post-init                   OK              0.97s
       > 182/193 nix-functional-tests:main / binary-cache-build-remote                        OK             12.76s
       > 183/193 nix-functional-tests:local-overlay-store / delete-duplicate                  OK              0.57s
       > 184/193 nix-functional-tests:local-overlay-store / optimise                          OK              0.55s
       > 185/193 nix-functional-tests:local-overlay-store / delete-refs                       OK              1.08s
       > 186/193 nix-functional-tests:local-overlay-store / verify                            OK              0.69s
       > 187/193 nix-functional-tests:flakes / non-flake-inputs                               OK              2.06s
       > 188/193 nix-functional-tests:local-overlay-store / gc                                OK              0.90s
       > 189/193 nix-functional-tests:ca / nix-copy                                           OK              6.99s
       > 190/193 nix-functional-tests:git-hashing / fixed                                     OK              2.28s
       > 191/193 nix-functional-tests:local-overlay-store / stale-file-handle                 OK              1.30s
       > 192/193 nix-functional-tests:ca / signatures                                         OK              6.80s
       > 193/193 nix-functional-tests:flakes / mercurial                                      OK              7.56s
       >
       > Summary of Failures:
       >
       > 164/193 nix-functional-tests:flakes / flakes                                FAIL            2.37s   exit status 1
       > 172/193 nix-functional-tests:flakes / relative-paths                        FAIL            0.45s   exit status 1
       >
       > Ok:                184
       > Fail:              2
       > Skipped:           7
       >
       > Full log written to /build/source/tests/functional/build/meson-logs/testlog.txt
       For full logs, run:
         nix-store -l /nix/store/7sf9wzlhvpfvplm733layngqaq5xrcc0-nix-functional-tests-2.30pre20250521_76a4d4c2.drv
error: 1 dependencies of derivation '/nix/store/l1amy5kf72ql5a79v82n3sjra0bf8ihb-nix-2.30pre20250521_76a4d4c2.drv' failed to build
error: 1 dependencies of derivation '/nix/store/4rqvynrwi73shj3xc9kbscy6n0q31hs4-activation-script.drv' failed to build
error: 1 dependencies of derivation '/nix/store/9xfny8ndaq2mcsrzijg0022j2nlafcgf-nix.conf.drv' failed to build
error: 1 dependencies of derivation '/nix/store/nmaxx2kxyfa9x9a1w1mqb05l6a26hrgm-home-manager-generation.drv' failed to build

fail.log

Expected behavior

The build to succeed

Metadata

nix-env (Nix) 2.26.2

Additional context

Checklist

• checked latest Nix manual (source)
• checked open bug issues and pull requests for possible duplicates

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