Fix eq none bug (#7938)

* fix reduce_sum scalar check bug

* fix equal none bug

* refine

* auto format by CI

Co-authored-by: oneflow-ci-bot <ci-bot@oneflow.org>
Co-authored-by: mergify[bot] <37929162+mergify[bot]@users.noreply.github.com>

python/oneflow/framework/tensor.py

@@ -118,7 +118,12 @@ def _meta_repr(self):
 
 
 def _eq(self, other):
-    return flow._C.equal(self, other)
+    if self is None and other is None:
+        return True
+    elif self is None or other is None:
+        return False
+    else:
+        return flow._C.equal(self, other)
 
 
 def _ne(self, other):

python/oneflow/test/tensor/test_tensor_part_1.py

@@ -1015,6 +1015,15 @@ def test_tensor_int(test_case):
         y = int(x)
         test_case.assertTrue(np.array_equal(y, 2))
 
+    def test_none_equal(test_case):
+        xt = flow.randn(10)
+        yt = flow.randn(10)
+        z = None in [xt, yt]
+        test_case.assertTrue(np.array_equal(z, False))
+        zt = None
+        z = None in [xt, yt, zt]
+        test_case.assertTrue(np.array_equal(z, True))
+
 
 if __name__ == "__main__":
     unittest.main()