Skip unsupported extensions

- Always skip unsupported extensions (like .egg) even when
  passing `ignore_compatibility=True`

pipenv/patched/notpip/index.py

@@ -653,7 +653,8 @@ class PackageFinder(object):
             if not ext:
                 self._log_skipped_link(link, 'not a file')
                 return
-            if ext not in SUPPORTED_EXTENSIONS and not ignore_compatibility:
+            # Always ignore unsupported extensions even when we ignore compatibility
+            if ext not in SUPPORTED_EXTENSIONS:
                 self._log_skipped_link(
                     link, 'unsupported archive format: %s' % ext)
                 return

pipenv/patched/notpip/req/req_set.py

@@ -97,11 +97,8 @@ def make_abstract_dist(req_to_install):
     """
     if req_to_install.editable:
         return IsSDist(req_to_install)
-    elif req_to_install.link:
-        if req_to_install.link.is_wheel:
-            return IsWheel(req_to_install)
-        elif req_to_install.link.ext == '.egg':
-            return IsEgg(req_to_install)
+    elif req_to_install.link and req_to_install.link.is_wheel:
+        return IsWheel(req_to_install)
     else:
         return IsSDist(req_to_install)
 
@@ -117,17 +114,6 @@ class IsWheel(DistAbstraction):
         pass
 
 
-# XXX: I don't know what I'm doing HALP. - uranusjr
-class IsEgg(DistAbstraction):
-
-    def dist(self, finder):
-        return pkg_resources.Distribution.from_filename(
-            self.req_to_install.source_dir)
-
-    def prep_for_dist(self):
-        pass
-
-
 class IsSDist(DistAbstraction):
 
     def dist(self, finder):