KeyboardInterrupt tests

KeyboardInterrupt tests now cover both scipy optimization and tf
optimization.

GPflow/model.py

@@ -291,7 +291,7 @@ def _optimize_np(self, method='L-BFGS-B', callback=None, max_iters=1000, **kw):
                         tol=None, # TODO: tol??
                         callback=callback,
                         options=options)
-        except (KeyboardInterrupt): # pragma: no cover
+        except (KeyboardInterrupt):
             print("Caught KeyboardInterrupt, setting model with most recent state.")
             self.set_state(obj._previous_x)
             return None 

testing/test_model.py

@@ -45,14 +45,22 @@ def setUp(self):
         Z = np.random.randn(100, 3)
         self.m = GPflow.sgpr.SGPR(X, Y, Z=Z, kern=GPflow.kernels.RBF(3))
 
-    def test(self):
+    def test_optimize_np(self):
         x0 = self.m.get_free_state()
         self.m._compile()
         self.m._objective = KeyboardRaiser(15, self.m._objective)
         self.m.optimize(display=0, max_iters=10000, ftol=0, gtol=0)
         x1 = self.m.get_free_state()
         self.failIf(np.allclose(x0, x1))
 
+    def test_optimize_tf(self):
+        x0 = self.m.get_free_state()
+        callback = KeyboardRaiser(5, lambda x: None)
+        o = tf.train.AdamOptimizer()
+        self.m.optimize(o, max_iters=15, callback=callback)
+        x1 = self.m.get_free_state()
+        self.failIf(np.allclose(x0, x1))
+
 
 if __name__ == "__main__":
     unittest.main()