nix-env silently collides propagated-user-env-packages

[cleverca22]

collisions that occur while trying to obey nix-support/propagated-user-env-packages are silently ignored

as an example:

[clever@laptop:~]$ cat /nix/store/xi66kayy945y4ycc6fim4bffap935d6x-wpa_gui-2.6/nix-support/propagated-user-env-packages 
 /nix/store/fhsiyhrssrzwdhx2dgy1ghadpmwq0lks-qtbase-5.9.0-bin
[clever@laptop:~]$ cat /nix/store/k60z1dnzw2vrp6hv3y79bbzd8w1zv218-wireshark-qt-2.4.1/nix-support/propagated-user-env-packages
/nix/store/w24yh0wxh1s4d8bq7qkgd65fmv4zmlbq-qtbase-5.9.1-bin ...

wpa-gui depends on 5.9.0
wireshark depends on 5.9.1

[clever@laptop:~]$ nix-store -qR .nix-profile | grep qt

[clever@laptop:~]$ 

nothing in my profile depends on anything QT related

[clever@laptop:~]$ nix-env -i /nix/store/xi66kayy945y4ycc6fim4bffap935d6x-wpa_gui-2.6
installing ‘wpa_gui-2.6’
[clever@laptop:~]$ ls -l .nix-profile/lib/qt-5.9
lrwxrwxrwx 1 root root 71 Dec 31  1969 .nix-profile/lib/qt-5.9 -> /nix/store/fhsiyhrssrzwdhx2dgy1ghadpmwq0lks-qtbase-5.9.0-bin/lib/qt-5.9

the 5.9.0 libraries are now in my profile

[clever@laptop:~]$ nix-env -i /nix/store/k60z1dnzw2vrp6hv3y79bbzd8w1zv218-wireshark-qt-2.4.1
installing ‘wireshark-qt-2.4.1’
[clever@laptop:~]$ ls -l .nix-profile/lib/qt-5.9
total 17
dr-xr-xr-x 11 root root 16 Dec 31  1969 plugins
[clever@laptop:~]$ ls -l .nix-profile/lib/qt-5.9/plugins/platforms/
total 2
lrwxrwxrwx 1 root root 104 Dec 31  1969 libqminimal.so -> /nix/store/fhsiyhrssrzwdhx2dgy1ghadpmwq0lks-qtbase-5.9.0-bin/lib/qt-5.9/plugins/platforms/libqminimal.so

the 5.9.0 libraries are still in my profile

[clever@laptop:~]$ wireshark 
Cannot mix incompatible Qt library (version 0x50900) with this library (version 0x50901)

and they break wireshark

[clever@laptop:~]$ nix-env -e wpa_gui
uninstalling ‘wpa_gui-2.6’
building path(s) ‘/nix/store/dxns08cqfyacwm5dahhzyb97f0kz9ggb-user-environment’
created 514 symlinks in user environment

[clever@laptop:~]$ wireshark 

removing wpa_gui restores the ability to run wireshark

[ghost]

This explodes my plasmashell. :P :(

Fixed by removing things depending on another qt version from the user env, as advised. Not a very nice fix.

[dtzWill]

Is this a nix (nix-env) bug?
Should this result in an error? (assuming no simple way resolve conflict such that both work?)

[ghost]

Presumably the fix would be fixing/isolating qt version more granularly if I recall what clever said correctly. In my case the collision was between 5.9.1 and 5.9.2, both residing in the same qt-5.9 directory. No doubt he will have better info.

[dtzWill]

While improving/changing the handling of qt deps solves the immediate concern, if I'm understanding correctly there is still the issue of conflicts in propagated-user-env-packages being silently ignored.

As my questions above hint, I think this is a bug and attempts to install packages with such conflicts should be an error. Especially if the result is (likely) broken anyway.

[ghost]

Ah you're right, my mind was elsewhere and missed the point. :)

[stale]

Thank you for your contributions.

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