commit 5b8256ce1832cb387bb567143309c4b543d62bd9
Author: Emily <18535642+emilazy@users.noreply.github.com>
Date:   Tue Feb 19 00:11:43 2019 +0100

    hdl.ast: remove unnecessary definition of __hash__.
    
    "A class that overrides __eq__() and does not define __hash__() will
    have its __hash__() implicitly set to None."
      -- https://docs.python.org/3.7/reference/datamodel.html#object.__hash__

diff --git a/nmigen/hdl/ast.py b/nmigen/hdl/ast.py
index 3dd8809..0ebde34 100644
--- a/nmigen/hdl/ast.py
+++ b/nmigen/hdl/ast.py
@@ -207,8 +207,6 @@ class Value(metaclass=ABCMeta):
     def _as_const(self):
         raise TypeError("Value {!r} cannot be evaluated as constant".format(self))
 
-    __hash__ = None
-
 
 class Const(Value):
     """A constant, literal integer value.

commit bfc920e873db38cc8c4f6a314073f337c611969c
Author: Emily <18535642+emilazy@users.noreply.github.com>
Date:   Tue Feb 19 00:25:00 2019 +0100

    test.test_hdl_ast: remove duplicate test_bool definition.

diff --git a/nmigen/test/test_hdl_ast.py b/nmigen/test/test_hdl_ast.py
index 9f20d17..a20c8d7 100644
--- a/nmigen/test/test_hdl_ast.py
+++ b/nmigen/test/test_hdl_ast.py
@@ -238,11 +238,6 @@ class OperatorTestCase(FHDLTestCase):
         v4 = Mux(s, Const(0, (4, False)), Const(0, (4, True)))
         self.assertEqual(v4.shape(), (5, True))
 
-    def test_bool(self):
-        v = Const(0).bool()
-        self.assertEqual(repr(v), "(b (const 1'd0))")
-        self.assertEqual(v.shape(), (1, False))
-
     def test_hash(self):
         with self.assertRaises(TypeError):
             hash(Const(0) + Const(0))