Add another test of CSE and feeds. (#87)

As a follow-up to #86, check that our CSE isn't too aggressive to prevent feeds
of pure ops with distinct names.

tensorflow-ops/tests/OpsTest.hs

@@ -79,10 +79,24 @@ testPlaceholderCse = testCase "testPlaceholderCse" $ TF.runSession $ do
     result <- TF.runWithFeeds [TF.feed p1 (enc 2), TF.feed p2 (enc 3)] $ p1 + p2
     liftIO $ result @=? TF.Scalar 5
 
+-- | Test that regular tensors can also be used for feeds, as long as they each
+-- have a different name.
+testScalarFeedCse :: Test
+testScalarFeedCse = testCase "testScalarFeedCse" $ TF.runSession $ do
+    p1 <- TF.render $ TF.scalar' (TF.opName .~ "A") 0
+    -- The second op is identical to the first other than its name; make sure
+    -- we don't aggressively CSE them together and prevent feeding them
+    -- separately.
+    p2 <- TF.render $ TF.scalar' (TF.opName .~ "B") 0
+    let enc :: Float -> TF.TensorData Float
+        enc n = TF.encodeTensorData [] (V.fromList [n])
+    result <- TF.runWithFeeds [TF.feed p1 (enc 2), TF.feed p2 (enc 3)] $ p1 + p2
+    liftIO $ result @=? TF.Scalar 5
 
 main :: IO ()
 main = googleTest [ testSaveRestore
                   , testSize
                   , testReducedShape
                   , testPlaceholderCse
+                  , testScalarFeedCse
                   ]