Fix wheel-based installations to include variety_build_settings

Fixes varietywalls#795

This could also move the cleanup to a custom cmdclass,
but it is not necessary.

Co-Authored-By: Miro Hrončok <miro@hroncok.cz>

Author: Martin Gansser

setup.py

@@ -20,6 +20,7 @@
 
 import os
 import sys
+from setuptools.command.build_py import build_py as _build_py
 
 from variety_lib.varietyconfig import get_version
 
@@ -41,14 +42,15 @@
 BUILD_SETTINGS_PATH = "variety_lib/variety_build_settings.py"
 
 
-class InstallWithDataDirectory(DistUtilsExtra.auto.install_auto):
+
+class BuildWithDataDirectory(_build_py):
     def run(self):
-        data_path = os.path.join(self.prefix, "share/variety/")
+        data_path = os.path.join(sys.prefix, "share/variety/")
         with open(BUILD_SETTINGS_PATH, "w") as f:
             f.write("### Autogenerated by setup.py - do not edit!\n")
             f.write("__variety_data_directory__ = %r\n" % data_path)
-        print("This build will look for Variety's data in %r." % data_path)
-        DistUtilsExtra.auto.install_auto.run(self)
+        print(f"[build_py] This build will look for Variety's data in {data_path!r}.")
+        super().run()
 
 
 DistUtilsExtra.auto.setup(
@@ -69,7 +71,7 @@ def run(self):
 Variety also includes a range of image effects, such as oil painting and blur,
 as well as options to layer quotes and a clock onto the background.""",
     url="https://github.com/varietywalls/variety",
-    cmdclass={"install": InstallWithDataDirectory},
+    cmdclass={"build_py": BuildWithDataDirectory},
     data_files=[("share/metainfo", ["variety.appdata.xml"])],
 )