Browse message value properties by record with bounded pages

crates/oa-desktop/src/data_values.rs

@@ -97,6 +97,7 @@ fn sorted_choices(mut choices: Vec<FieldPathChoice>) -> Vec<FieldPathChoice> {
     choices
 }
 
+#[cfg(test)]
 pub fn choices(
     project: &Project,
     exchange: &Relation,
@@ -142,6 +143,19 @@ pub fn roots(project: &Project, exchange: &Relation, phase: &MessageKind) -> Vec
     )
 }
 
+/// Browse one record at a time, including explicitly chosen recursive hops.
+pub fn at_scope(
+    project: &Project,
+    exchange: &Relation,
+    phase: &MessageKind,
+    scope: Option<&FieldPathKey>,
+) -> Result<Vec<FieldPathChoice>, String> {
+    match scope {
+        Some(key) => children(project, exchange, phase, key),
+        None => Ok(roots(project, exchange, phase)),
+    }
+}
+
 /// Resolve authored finite paths as well as the finite representative picker list.
 /// In particular, optional recursive Value records may be traversed repeatedly.
 pub fn resolve(