Apply as_variable to no-cast result

chainer · Aug 28, 2017 · 2abe136 · 2abe136
1 parent 9f7e13e
commit 2abe136
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Showing 2 changed files with 10 additions and 4 deletions.
diff --git a/chainer/functions/array/cast.py b/chainer/functions/array/cast.py
@@ -1,3 +1,4 @@
+import chainer
 from chainer import function_node
 from chainer.utils import type_check
 
@@ -51,5 +52,5 @@ def cast(x, typ):
 
     """
     if x.dtype == typ:
-        return x
+        return chainer.as_variable(x)
     return Cast(typ).apply((x,))[0]
diff --git a/tests/chainer_tests/functions_tests/array_tests/test_cast.py b/tests/chainer_tests/functions_tests/array_tests/test_cast.py
@@ -65,13 +65,18 @@ def setUp(self):
 
     def check_forward_no_cast(self, x_data):
         y = functions.cast(x_data, self.dtype)
-        self.assertIs(y, x_data)
+        self.assertIsInstance(y, chainer.Variable)
+        self.assertIs(y.data, x_data)
 
     def test_forward_no_cast_array(self):
-        self.check_forward_no_cast(self.x)
+        y = functions.cast(self.x, self.dtype)
+        self.assertIsInstance(y, chainer.Variable)
+        self.assertIs(y.data, self.x)
 
     def test_forward_no_cast_variable(self):
-        self.check_forward_no_cast(chainer.Variable(self.x))
+        x = chainer.Variable(self.x)
+        y = functions.cast(x, self.dtype)
+        self.assertIs(y, x)
 
 
 testing.run_module(__name__, __file__)