Rename an op to BadSub to make it clear that it behave incorrectly.

theano/gof/tests/test_cc.py

@@ -129,7 +129,7 @@ class Add(Binary):
 add = Add()
 
 
-class Sub(Binary):
+class BadSub(Binary):
     def c_code(self, node, name, inp, out, sub):
         x, y = inp
         z, = out
@@ -137,7 +137,7 @@ class Sub(Binary):
 
     def impl(self, x, y):
         return -10  # erroneous (most of the time)
-sub = Sub()
+bad_sub = BadSub()
 
 
 class Mul(Binary):
@@ -180,7 +180,7 @@ def Env(inputs, outputs):
 
 def test_clinker_straightforward():
     x, y, z = inputs()
-    e = add(mul(add(x, y), div(x, y)), sub(sub(x, y), z))
+    e = add(mul(add(x, y), div(x, y)), bad_sub(bad_sub(x, y), z))
     lnk = CLinker().accept(Env([x, y, z], [e]))
     fn = lnk.make_function()
     assert fn(2.0, 2.0, 2.0) == 2.0
@@ -189,7 +189,7 @@ def test_clinker_straightforward():
 def test_clinker_literal_inlining():
     x, y, z = inputs()
     z = Constant(tdouble, 4.12345678)
-    e = add(mul(add(x, y), div(x, y)), sub(sub(x, y), z))
+    e = add(mul(add(x, y), div(x, y)), bad_sub(bad_sub(x, y), z))
     lnk = CLinker().accept(Env([x, y], [e]))
     fn = lnk.make_function()
     assert abs(fn(2.0, 2.0) + 0.12345678) < 1e-9
@@ -232,7 +232,7 @@ def test_clinker_dups_inner():
 
 def test_opwiseclinker_straightforward():
     x, y, z = inputs()
-    e = add(mul(add(x, y), div(x, y)), sub(sub(x, y), z))
+    e = add(mul(add(x, y), div(x, y)), bad_sub(bad_sub(x, y), z))
     lnk = OpWiseCLinker().accept(Env([x, y, z], [e]))
     fn = lnk.make_function()
     assert fn(2.0, 2.0, 2.0) == 2.0
@@ -273,8 +273,8 @@ def test_duallinker_straightforward():
 
 def test_duallinker_mismatch():
     x, y, z = inputs()
-    # sub is correct in C but erroneous in Python
-    e = sub(mul(x, y), mul(y, z))
+    # bad_sub is correct in C but erroneous in Python
+    e = bad_sub(mul(x, y), mul(y, z))
     g = Env([x, y, z], [e])
     lnk = DualLinker(checker=_my_checker).accept(g)
     fn = lnk.make_function()
@@ -283,6 +283,7 @@ def test_duallinker_mismatch():
     assert CLinker().accept(g).make_function()(1.0, 2.0, 3.0) == -4.0
     # good
     assert OpWiseCLinker().accept(g).make_function()(1.0, 2.0, 3.0) == -4.0
+
     # (purposely) wrong
     assert PerformLinker().accept(g).make_function()(1.0, 2.0, 3.0) == -10.0