PyPy cannot do Gaviota

README.rst

@@ -290,19 +290,6 @@ Features
 * Probe Gaviota endgame tablebases (DTM, WDL).
   `Docs <https://python-chess.readthedocs.io/en/latest/gaviota.html>`__.
 
-  .. code:: python
-
-      >>> import chess.gaviota
-
-      >>> tablebases = chess.gaviota.open_tablebases("data/gaviota")
-
-      >>> # White to move mates in 31 half moves in this KRvK endgame.
-      >>> board = chess.Board("8/8/8/8/4k3/8/6R1/7K w - - 0 1")
-      >>> tablebases.probe_dtm(board)
-      31
-
-      >>> tablebases.close()
-
 * Probe Syzygy endgame tablebases (DTZ, WDL).
   `Docs <https://python-chess.readthedocs.io/en/latest/syzygy.html>`__.
 

setup.py

@@ -59,14 +59,17 @@ def dependencies():
 
 def extra_dependencies():
     extras = {}
-    extras["uci"] = []
-    extras["gaviota"] = []
 
     if sys.version_info < (3, 2):
         extras["uci"] = ["futures"]
+    else:
+        extras["uci"] = []
 
-    if sys.version_info < (3, 3):
-        extras["gaviota"] = ["backports.lzma"]
+    if platform.python_implementation() == "CPython":
+        if sys.version_info < (3, 3):
+            extras["gaviota"] = ["backports.lzma"]
+        else:
+            extras["gaviota"] = []
 
     return extras
 

test.py

@@ -2642,6 +2642,9 @@ def test_issue_93(self):
 class NativeGaviotaTestCase(unittest.TestCase):
 
     def setUp(self):
+        if platform.python_implementation() != "CPython":
+            self.skipTest("need CPython for native Gaviota")
+
         try:
             self.tablebases = chess.gaviota.open_tablebases_native("data/gaviota")
         except (OSError, RuntimeError):