working unit test currently fails as expected

test/topological_sort.cpp

@@ -21,9 +21,13 @@
 
 #include "ngraph/log.hpp"
 #include "ngraph/ngraph.hpp"
+#include "ngraph/pass/assign_tensors.hpp"
 #include "ngraph/pass/collect_functions.hpp"
+#include "ngraph/pass/dump_sorted.hpp"
 #include "ngraph/pass/manager.hpp"
+#include "ngraph/pass/propagate_types.hpp"
 #include "ngraph/pass/topological_sort.hpp"
+#include "ngraph/pass/visualize_tree.hpp"
 #include "ngraph/util.hpp"
 #include "test_tools.hpp"
 
@@ -184,3 +188,26 @@ TEST(topological_sort, collect_functions)
     EXPECT_TRUE(contains(fnames, "g"));
     EXPECT_TRUE(contains(fnames, "h"));
 }
+
+TEST(topological_sort, unused_function_arg)
+{
+    // Create a function with an unused argument
+    // B is unused in the function but must be in the graph
+    auto shape = Shape{2, 2};
+    auto A = make_shared<op::Parameter>(element::Float32::element_type(), shape);
+    auto B = make_shared<op::Parameter>(element::Float32::element_type(), shape);
+    auto C = make_shared<op::Parameter>(element::Float32::element_type(), shape);
+    auto rt_f = make_shared<TensorViewType>(element::Float32::element_type(), shape);
+    auto result = A + C + C;
+    auto f = make_shared<Function>(result, rt_f, op::Parameters{A, B, C}, "f");
+
+    pass::Manager pass_manager;
+    pass_manager.register_pass<pass::TopologicalSort>();
+    pass_manager.register_pass<pass::PropagateTypes>();
+    pass_manager.register_pass<pass::AssignTensors>();
+    // pass_manager.register_pass<pass::DumpSorted>("sorted.txt");
+    pass_manager.run_passes(f);
+    list<shared_ptr<Node>> ops = f->get_ordered_ops();
+
+    EXPECT_EQ(5, ops.size());
+}