addEdge(N1, N1, E11);
    addEdge(N1, N2, E12);
    assertThat(network.adjacentEdges(E11)).containsExactly(E12);
  }

  @Test
  public void edgesConnecting_selfLoop() {
    assume().that(network.allowsSelfLoops()).isTrue();

    addEdge(N1, N1, E11);
    assertThat(network.edgesConnecting(N1, N1)).containsExactly(E11);
    addEdge(N1, N2, E12);

                if (vertex != null) {
                    addEdge(projectVertex, vertex, project, projectMap, force, safe);
                }
            } else {
                for (Vertex vertex : vertices.values()) {
                    addEdge(projectVertex, vertex, project, projectMap, force, safe);
                }
            }
        }
    }

    private void addEdge(
            Vertex fromVertex,

  TF_CHECK_OK(scope.DoShapeInference(launch));
  scope.graph()->AddEdge(a.node(), 0, launch, 0);
  scope.graph()->AddEdge(b.node(), 0, launch, 1);
  scope.graph()->AddEdge(c.node(), 0, launch, 2);
  scope.graph()->AddEdge(d.node(), 0, launch, 3);
  scope.graph()->AddEdge(u.node(), 0, launch, 4);
  scope.graph()->AddEdge(v.node(), 0, launch, 5);
  scope.graph()->AddEdge(w.node(), 0, launch, 6);

  auto out0 =

        {
            ArtifactMetadata md = node.getMd();
            MetadataGraphEdge e =
                    new MetadataGraphEdge(md.version, md.resolved, md.artifactScope, md.artifactUri, depth, pomOrder);
            addEdge(parentVertex, vertex, e);
        } else {
            entry = vertex;
        }

        MetadataTreeNode[] kids = node.getChildren();
        if (kids == null || kids.length < 1) {
            return;

    auto sink = ops::Identity(scope.WithOpName("sink"), exit);

    // Remove the dummy node and add the loop backedge.
    scope.graph()->RemoveNode(dummy.node());
    scope.graph()->AddEdge(next_iteration.node(), 0, merge.output.node(), 1);

    TF_EXPECT_OK(scope.ToGraph(&graph));
  }

  GraphShapeInfo shape_info;
  TF_ASSERT_OK(InferShapes(&graph, /*arg_shapes=*/{}, /*fnlib_def=*/nullptr,

      << "Use of BlockArgument encounted before def!";
  // For argument, there is only one result output, so the index is always 0.
  graph_->AddEdge(input_node_it->second, 0, dst_node, dst_index);
  return absl::OkStatus();
}

Status Exporter::AddEdge(Operation* inst) {
  // For tf_executor.fetch, add only its data edges. Control edges are captured
  // later.

      << "Use of BlockArgument encounted before def!";
  // For argument, there is only one result output, so the index is always 0.
  graph_->AddEdge(input_node_it->second, 0, dst_node, dst_index);
  return absl::OkStatus();
}

Status Exporter::AddEdge(Operation* inst) {
  // For tf_executor.fetch, add only its data edges. Control edges are captured
  // later.

      TF_ASSIGN_OR_RETURN(placeholder_node, g->AddNode(placeholder_def));
      placeholders[placeholder_index] = placeholder_node;
    } else {
      placeholder_node = iter->second;
    }
    g->AddEdge(placeholder_node, 0, dst, dst_input);

    // Replace `e->dst()` because its input node changed.
    NodeDef new_def = dst->def();
    *new_def.mutable_input(dst_input) = placeholder_node->name();

    // TODO(sanjoy): This does not update NodeDef inputs.  To be able to update
    // NodeDef inputs we first need to fix encapsulate_subgraphs_pass to fix up
    // the NodeDef inputs to the function call nodes.
    g->AddEdge(new_node, edge->src_output(), edge->dst(), edge->dst_input());
    g->RemoveEdge(edge);
  }
}

// Returns a data value that is dead iff `control` is dead.
Output ControlToData(const Scope& scope, Node* control) {

      graph->AddEdge(data_inputs[i].first, data_inputs[i].second, xla_launch,
                     i);
    }
    for (Node* n : control_inputs) {
      graph->AddControlEdge(n, xla_launch);
    }
    for (int i = 0, end = data_outputs.size(); i < end; ++i) {
      for (const auto& successor : data_outputs[i]) {
        graph->AddEdge(xla_launch, i, successor.first, successor.second);
      }