Fix size of histc return on CPU when input is 0-dimensional and bins=1.

gchanan · gchanan · commit bc03f27408aa · 2019-06-06T15:26:10.000-07:00
This triggers the wrong scalar_check unless it is explicitly overridden (because the heuristic uses the shape of the input).
This wasn't an issue on CUDA because it didn't use TH, so doesn't have scalar checks.

gh-metadata: pytorch pytorch 21497 gh/gchanan/26/head
diff --git a/aten/src/ATen/Declarations.cwrap b/aten/src/ATen/Declarations.cwrap
@@ -1758,6 +1758,7 @@
   variants:
     - function
   return: argument 0
+  scalar_check: false
   arguments:
     - arg: THTensor* result
       output: True
diff --git a/test/test_torch.py b/test/test_torch.py
@@ -2646,6 +2646,13 @@ def test_histc(self):
                 torch.tensor([0, 2, 1, 0], dtype=torch.float, device=device),
                 actual)
             self.assertEqual(actual.dtype, torch.float)
+            # scalar input and 1 bin -- should return a 1-dimensional tensor, not a scalar.
+            actual = torch.histc(
+                torch.tensor(0, dtype=torch.float, device=device),
+                bins=1, min=0, max=3)
+            self.assertEqual(
+                torch.tensor([1], dtype=torch.float, device=device),
+                actual)
 
         # test against numpy.histogram()
         def test_against_np(tensor, bins=100, min=0, max=0):
