Support External Classes' __rtruediv__ (#831)

return NotImplemented when __truediv__ is called with a non-string.

CHANGES/832.feature.rst

@@ -0,0 +1 @@
+Made :py:meth:`URL.__truediv__` return ``NotImplemented`` if called with an unsupported type — by :user:`michaeljpeters`.

tests/test_url.py

@@ -715,6 +715,12 @@ def test_div_path_starting_from_slash_is_forbidden():
         url / "/to/others"
 
 
+def test_div_bad_type():
+    url = URL("http://example.com/path/")
+    with pytest.raises(TypeError):
+        url / 3
+
+
 def test_div_cleanup_query_and_fragment():
     url = URL("http://example.com/path?a=1#frag")
     assert str(url / "to") == "http://example.com/path/to"

yarl/_url.py

@@ -341,6 +341,8 @@ def __gt__(self, other):
         return self._val > other._val
 
     def __truediv__(self, name):
+        if not type(name) is str:
+            return NotImplemented
         return self._make_child((name,))
 
     def __mod__(self, query):