feat: dataflow_ports_only function to filter node-ports

src/hugr/views.rs

@@ -590,6 +590,19 @@ impl<T: AsRef<Hugr>> HugrView for T {
     }
 }
 
+/// Filter an iterator of node-ports to only dataflow dependency specifying
+/// ports (Value and StateOrder)
+pub fn dataflow_ports_only<'i, 'a: 'i, P: Into<Port> + Copy>(
+    hugr: &'a impl HugrView,
+    it: impl Iterator<Item = (Node, P)> + 'i,
+) -> impl Iterator<Item = (Node, P)> + 'i {
+    it.filter(move |(n, p)| {
+        matches!(
+            hugr.get_optype(*n).port_kind(*p),
+            Some(EdgeKind::Value(_) | EdgeKind::StateOrder)
+        )
+    })
+}
 pub(crate) mod sealed {
     use super::*;
 

src/hugr/views/tests.rs

@@ -1,4 +1,3 @@
-use itertools::Itertools;
 use portgraph::PortOffset;
 use rstest::{fixture, rstest};
 
@@ -153,6 +152,8 @@ fn value_types() {
 #[test]
 fn static_targets() {
     use crate::extension::prelude::{ConstUsize, USIZE_T};
+    use itertools::Itertools;
+
     let mut dfg = DFGBuilder::new(FunctionType::new(type_row![], type_row![USIZE_T])).unwrap();
 
     let c = dfg.add_constant(ConstUsize::new(1).into(), None).unwrap();
@@ -170,3 +171,44 @@ fn static_targets() {
         &[(load.node(), 0.into())]
     )
 }
+
+#[rustversion::since(1.75)] // uses impl in return position
+#[test]
+fn test_dataflow_ports_only() {
+    use crate::builder::DataflowSubContainer;
+    use crate::extension::prelude::BOOL_T;
+    use crate::hugr::views::dataflow_ports_only;
+    use crate::std_extensions::logic::test::not_op;
+    use itertools::Itertools;
+    let mut dfg = DFGBuilder::new(FunctionType::new(type_row![BOOL_T], type_row![BOOL_T])).unwrap();
+    let local_and = {
+        let local_and = dfg
+            .define_function(
+                "and",
+                FunctionType::new(type_row![BOOL_T; 2], type_row![BOOL_T]).pure(),
+            )
+            .unwrap();
+        let first_input = local_and.input().out_wire(0);
+        local_and.finish_with_outputs([first_input]).unwrap()
+    };
+    let [in_bool] = dfg.input_wires_arr();
+
+    let not = dfg.add_dataflow_op(not_op(), [in_bool]).unwrap();
+    let call = dfg.call(local_and.handle(), [not.out_wire(0); 2]).unwrap();
+    dfg.add_other_wire(not.node(), call.node()).unwrap();
+    let h = dfg
+        .finish_hugr_with_outputs(not.outputs(), &crate::extension::PRELUDE_REGISTRY)
+        .unwrap();
+    let filtered_ports = dataflow_ports_only(&h, h.all_linked_outputs(call.node())).collect_vec();
+
+    // should ignore the static input in to call, but report the two value ports
+    // and the order port.
+    assert_eq!(
+        &filtered_ports[..],
+        &[
+            (not.node(), 0.into()),
+            (not.node(), 0.into()),
+            (not.node(), 1.into())
+        ]
+    )
+}