34185 / 35668: fixes according to review

Author: soehms

src/bin/sage-runtests

@@ -54,7 +54,7 @@ if __name__ == "__main__":
              'Note that "!" needs to be quoted or escaped in the shell.')
     parser.add_argument("--hide", metavar="FEATURES", default="",
         help='run tests pretending that the software listed in FEATURES (separated by commas) is not installed; '
-             'if "all" is listed, will also hide features corresponding to all non standard packages; '
+             'if "all" is listed, will also hide features corresponding to all optional or experimental packages; '
              'if "optional" is listed, will also hide features corresponding to optional packages.')
     parser.add_argument("--randorder", type=int, metavar="SEED", help="randomize order of tests")
     parser.add_argument("--random-seed", dest="random_seed", type=int, metavar="SEED", help="random seed (integer) for fuzzing doctests",

src/sage/features/__init__.py

@@ -295,7 +295,7 @@ def resolution(self):
 
     def joined_features(self):
         r"""
-        Return a list of features joined with ``self``.
+        Return a list of features that ``self`` is the join of.
 
         OUTPUT:
 
@@ -306,14 +306,22 @@ def joined_features(self):
             sage: from sage.features.graphviz import Graphviz
             sage: Graphviz().joined_features()
             [Feature('dot'), Feature('neato'), Feature('twopi')]
+            sage: from sage.features.sagemath import sage__rings__function_field
+            sage: sage__rings__function_field().joined_features()
+            [Feature('sage.rings.function_field.function_field_polymod'),
+            Feature('sage.libs.singular'),
+            Feature('sage.libs.singular.singular'),
+            Feature('sage.interfaces.singular')]
             sage: from sage.features.interfaces import Mathematica
             sage: Mathematica().joined_features()
             []
         """
         from sage.features.join_feature import JoinFeature
+        res = []
         if isinstance(self, JoinFeature):
-            return self._features
-        return []
+            for f in self._features:
+                res += [f] + f.joined_features()
+        return res
 
     def is_standard(self):
         r"""