bug#35597: GNOME Tweak Tool does not start

[sirgazil]

Hi,

I installed the GNU system in a real machine using Guix 1.0 ISO installer 
(https://ftp.gnu.org/gnu/guix/guix-system-install-1.0.0.x86_64-linux.iso.xz).

After installing "gnome-tweak-tool", I cannot launch it.


## Steps to reproduce

1. guix install gnome-tweak-tool
2. Press Alt+F2
3. Type gnome-tweak-tool and press Enter


## Unexpected result

The application never starts.


## Expected result.

The application starts


## Additional information

Almost every time I run "gnome-tweak-tool" in a terminal nothing happens. I 
immediately get another prompt.

Just one time I got the following warnings and errors:

##############################
$ gnome-tweak-tool 

** (..gnome-tweak-tool-real-real:879): WARNING **: 19:05:05.203: Failed to load 
shared library 'libsoup-2.4.so.1' referenced by the typelib: libsoup-2.4.so.1: 
no se puede abrir el fichero del objeto compartido: No existe el fichero o el 
directorio
WARNING : Error detecting shell
Traceback (most recent call last):
  File 
"/gnu/store/ir0chxqf6319hgzigqcn8wjrc61ywvbs-gnome-tweak-tool-3.26.4/lib/python3.7/site-packages/gtweak/tweaks/tweak_group_shell_extensions.py",
 line 216, in __init__
    ego = ExtensionsDotGnomeDotOrg(version)
  File 
"/gnu/store/ir0chxqf6319hgzigqcn8wjrc61ywvbs-gnome-tweak-tool-3.26.4/lib/python3.7/site-packages/gtweak/egowrapper.py",
 line 38, in __init__
    self._session = Soup.Session.new()
GLib.GError: g-invoke-error-quark: Could not locate soup_session_new: 
libsoup-2.4.so.1: no se puede abrir el fichero del objeto compartido: No existe 
el fichero o el directorio (1)
WARNING : Error detecting shell
Traceback (most recent call last):
  File 
"/gnu/store/ir0chxqf6319hgzigqcn8wjrc61ywvbs-gnome-tweak-tool-3.26.4/lib/python3.7/site-packages/gtweak/tweaks/tweak_group_shell_extensions.py",
 line 50, in __init__
    self._swInfo = Gio.DesktopAppInfo.new("org.gnome.Software.desktop")
TypeError: constructor returned NULL
Traceback (most recent call last):
  File 
"/gnu/store/ir0chxqf6319hgzigqcn8wjrc61ywvbs-gnome-tweak-tool-3.26.4/lib/python3.7/site-packages/gtweak/widgets.py",
 line 164, in __init__
    self.settings = GSettingsSetting(schema_name, **options)
  File 
"/gnu/store/ir0chxqf6319hgzigqcn8wjrc61ywvbs-gnome-tweak-tool-3.26.4/lib/python3.7/site-packages/gtweak/gsettings.py",
 line 137, in __init__
    raise GSettingsMissingError(schema_name)
gtweak.gsettings.GSettingsMissingError: org.gnome.mutter

During handling of the above exception, another exception occurred:

Traceback (most recent call last):
  File 
"/gnu/store/ir0chxqf6319hgzigqcn8wjrc61ywvbs-gnome-tweak-tool-3.26.4/lib/python3.7/site-packages/gtweak/app.py",
 line 43, in do_activate
    self.win = Window(self, model)
  File 
"/gnu/store/ir0chxqf6319hgzigqcn8wjrc61ywvbs-gnome-tweak-tool-3.26.4/lib/python3.7/site-packages/gtweak/tweakview.py",
 line 59, in __init__
    self._model.load_tweaks(self)
  File 
"/gnu/store/ir0chxqf6319hgzigqcn8wjrc61ywvbs-gnome-tweak-tool-3.26.4/lib/python3.7/site-packages/gtweak/tweakmodel.py",
 line 117, in load_tweaks
    mods = __import__("gtweak.tweaks", globals(), locals(), tweak_files, 0)
  File 
"/gnu/store/ir0chxqf6319hgzigqcn8wjrc61ywvbs-gnome-tweak-tool-3.26.4/lib/python3.7/site-packages/gtweak/tweaks/tweak_group_keymouse.py",
 line 274, in <module>
    OverviewShortcutTweak(),
  File 
"/gnu/store/ir0chxqf6319hgzigqcn8wjrc61ywvbs-gnome-tweak-tool-3.26.4/lib/python3.7/site-packages/gtweak/tweaks/tweak_group_keymouse.py",
 line 205, in __init__
    _GSettingsTweak.__init__(self, name, "org.gnome.mutter", "overlay-key", 
loaded=_shell_loaded, **options)
  File 
"/gnu/store/ir0chxqf6319hgzigqcn8wjrc61ywvbs-gnome-tweak-tool-3.26.4/lib/python3.7/site-packages/gtweak/widgets.py",
 line 173, in __init__
    logging.info("GSetting missing %s" % (e.message))
AttributeError: 'GSettingsMissingError' object has no attribute 'message'
##############################

The application didn't exit, I had to press Ctrl+C to get a prompt again.

Also, after running

    strace -f -o tweak-tool-trace.out gnome-tweak-tool

I can see many lines with "No such file or directory". For instance:

##############################
2694  
readlink("/gnu/store/zm3188ipzi262s0m8bxm24br77yh9pd8-python-3.7.0/bin/python3.7",
 0x7ffefe14afb0, 4096) = -1 EINVAL (Argumento inválido)
2694  openat(AT_FDCWD, 
"/gnu/store/zm3188ipzi262s0m8bxm24br77yh9pd8-python-3.7.0/bin/pyvenv.cfg", 
O_RDONLY) = -1 ENOENT (No existe el fichero o el directorio)
2694  openat(AT_FDCWD, 
"/gnu/store/zm3188ipzi262s0m8bxm24br77yh9pd8-python-3.7.0/pyvenv.cfg", 
O_RDONLY) = -1 ENOENT (No existe el fichero o el directorio)
2694  
stat("/gnu/store/zm3188ipzi262s0m8bxm24br77yh9pd8-python-3.7.0/bin/Modules/Setup",
 0x7ffefe151020) = -1 ENOENT (No existe el fichero o el directorio)
##############################

But I wouldn't know what to look for in that output.


---
https://sirgazil.bitbucket.io/