move set logic to PackageBase initializer (otherwise, users could instantiate package_class() in other locations and bypass the config)

lib/spack/spack/package_base.py

@@ -694,6 +694,13 @@ def __init__(self, spec):
 
         super(PackageBase, self).__init__()
 
+        # packages.yaml config can override package attributes. This is set
+        # on the instance rather than the class since the configuration can
+        # change between calls to repo.get for the same package.
+        settings = spack.config.get("packages").get(spec.name, {}).get("set", {})
+        for key, val in settings.items():
+            setattr(self, key, val)
+
     @classmethod
     def possible_dependencies(
         cls,

lib/spack/spack/repo.py

@@ -1169,7 +1169,7 @@ def get(self, spec):
 
         package_class = self.get_pkg_class(spec.name)
         try:
-            package_instance = package_class(spec)
+            return package_class(spec)
         except spack.error.SpackError:
             # pass these through as their error messages will be fine.
             raise
@@ -1182,15 +1182,6 @@ def get(self, spec):
                 sys.excepthook(*sys.exc_info())
             raise FailedConstructorError(spec.fullname, *sys.exc_info())
 
-        # packages.yaml config can override package attributes. This is set
-        # on the instance rather than the class since the configuration can
-        # change between calls to repo.get for the same package.
-        settings = spack.config.get("packages").get(spec.name, {}).get("set", {})
-        for key, val in settings.items():
-            setattr(package_instance, key, val)
-
-        return package_instance
-
     @autospec
     def dump_provenance(self, spec, path):
         """Dump provenance information for a spec to a particular path.