diff --git a/test/null/test_schedule.py b/test/null/test_schedule.py
index 1a14c1d646..f5f63e19da 100644
--- a/test/null/test_schedule.py
+++ b/test/null/test_schedule.py
@@ -234,6 +234,18 @@ class TestSchedule(unittest.TestCase):
     d = Tensor.empty(1).assign(c)
     check_schedule(d, 1)
 
+  def test_detach_assign(self):
+    a = Tensor.ones(4, 4).contiguous().realize()
+    buf1, buf2 = Tensor.empty(4, 4).contiguous(), Tensor.empty(4, 4).contiguous()
+    r = buf2.assign(buf1.assign(a + 1.0) * 2.0)
+    check_schedule(r.detach().contiguous(), 2)
+
+  def test_contiguous_backward_assign(self):
+    a = Tensor.ones(4, 4).contiguous().realize()
+    buf1, buf2 = Tensor.empty(4, 4).contiguous(), Tensor.empty(4, 4).contiguous()
+    r = buf2.assign(buf1.assign(a + 1.0) * 2.0)
+    check_schedule(r.contiguous_backward().contiguous(), 2)
+
   def test_mulacc_relu_fusion(self):
     a = Tensor.empty(10)
     b = Tensor.empty(10)
diff --git a/test/unit/test_function.py b/test/unit/test_function.py
index e3cf7335de..216c5763fc 100644
--- a/test/unit/test_function.py
+++ b/test/unit/test_function.py
@@ -70,6 +70,14 @@ class TestFunction(unittest.TestCase):
     b = Tensor([4,5,6])
     np.testing.assert_equal(f(a, b).numpy(), [5,7,9])
 
+  def test_contiguous_backward(self):
+    @function
+    def f(a:Tensor, b:Tensor) -> Tensor: return (a + b).contiguous_backward()
+
+    a = Tensor([1,2,3])
+    b = Tensor([4,5,6])
+    np.testing.assert_equal(f(a, b).numpy(), [5,7,9])
+
   def test_method(self):
     class Foo:
       def __init__(self): self.w = Tensor([10,20,30])