Keep nested data field names visible in compact pickers

crates/oa-desktop/src/data_values.rs

@@ -11,10 +11,11 @@ pub struct FieldPathKey {
 pub struct FieldPathChoice {
     pub key: FieldPathKey,
     pub label: String,
+    pub picker_label: String,
 }
 impl std::fmt::Display for FieldPathChoice {
     fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
-        f.write_str(&self.label)
+        f.write_str(&self.picker_label)
     }
 }
 
@@ -49,8 +50,7 @@ fn named_choice(project: &Project, entry: data::CarriedFieldPath) -> FieldPathCh
                 .map(|e| format!("{} (@{})", e.name, e.alias))
                 .unwrap_or_else(|| id.to_string())
         })
-        .collect::<Vec<_>>()
-        .join(" → ");
+        .collect::<Vec<_>>();
     let direction =
         if data::item_mechanism(project, entry.item) == Some(ExchangeMechanism::Operation) {
             match entry.direction {
@@ -63,54 +63,83 @@ fn named_choice(project: &Project, entry: data::CarriedFieldPath) -> FieldPathCh
         } else {
             ""
         };
+    let terminal = qualified
+        .last()
+        .expect("A field path always has a terminal");
+    let owner_path = qualified[..qualified.len() - 1].join(" → ");
+    let picker_label = format!(
+        "{terminal}{direction} — {}{}",
+        project.named(entry.item),
+        if owner_path.is_empty() {
+            String::new()
+        } else {
+            format!(" / {owner_path}")
+        },
+    );
     FieldPathChoice {
         key: FieldPathKey {
             path: entry.path,
             field: entry.field,
         },
-        label: format!("{} / {qualified}{direction}", project.named(entry.item)),
+        label: format!(
+            "{} / {}{direction}",
+            project.named(entry.item),
+            qualified.join(" → ")
+        ),
+        picker_label,
     }
 }
 
+// A bounded picker must expose its distinguishing field before a long path.
+// Keep the full address separately for the wrapping detail text.
+fn sorted_choices(mut choices: Vec<FieldPathChoice>) -> Vec<FieldPathChoice> {
+    choices.sort_by_cached_key(|choice| choice.picker_label.to_lowercase());
+    choices
+}
+
 pub fn choices(
     project: &Project,
     exchange: &Relation,
     phase: &MessageKind,
 ) -> Result<Vec<FieldPathChoice>, String> {
-    Ok(data::try_carried_field_paths(project, exchange)?
-        .into_iter()
-        .filter(|entry| phase_allows(project, entry, phase))
-        .map(|entry| named_choice(project, entry))
-        .collect())
+    Ok(sorted_choices(
+        data::try_carried_field_paths(project, exchange)?
+            .into_iter()
+            .filter(|entry| phase_allows(project, entry, phase))
+            .map(|entry| named_choice(project, entry))
+            .collect(),
+    ))
 }
 
 /// Direct carried fields only: an unrelated deep branch must not prevent
 /// browsing a root field. Preserve the core resolver's first carried owner.
 pub fn roots(project: &Project, exchange: &Relation, phase: &MessageKind) -> Vec<FieldPathChoice> {
     let mut seen = std::collections::BTreeSet::new();
-    exchange
-        .body
-        .items()
-        .iter()
-        .flat_map(|item| {
-            data::effective_fields(project, *item)
-                .into_iter()
-                .filter_map(|field| {
-                    let SharedBody::DataField { direction, .. } = field.shared()? else {
-                        return None;
-                    };
-                    Some(data::CarriedFieldPath {
-                        item: *item,
-                        path: vec![],
-                        field: field.id,
-                        direction: *direction,
+    sorted_choices(
+        exchange
+            .body
+            .items()
+            .iter()
+            .flat_map(|item| {
+                data::effective_fields(project, *item)
+                    .into_iter()
+                    .filter_map(|field| {
+                        let SharedBody::DataField { direction, .. } = field.shared()? else {
+                            return None;
+                        };
+                        Some(data::CarriedFieldPath {
+                            item: *item,
+                            path: vec![],
+                            field: field.id,
+                            direction: *direction,
+                        })
                     })
-                })
-        })
-        .filter(|entry| seen.insert(entry.field))
-        .filter(|entry| phase_allows(project, entry, phase))
-        .map(|entry| named_choice(project, entry))
-        .collect()
+            })
+            .filter(|entry| seen.insert(entry.field))
+            .filter(|entry| phase_allows(project, entry, phase))
+            .map(|entry| named_choice(project, entry))
+            .collect(),
+    )
 }
 
 /// Resolve authored finite paths as well as the finite representative picker list.
@@ -166,20 +195,22 @@ pub fn children(
     }
     let mut path = key.path.clone();
     path.push(key.field);
-    Ok(data::effective_fields(project, *record)
-        .into_iter()
-        .map(|field| {
-            named_choice(
-                project,
-                data::CarriedFieldPath {
-                    item: entry.item,
-                    path: path.clone(),
-                    field: field.id,
-                    direction: entry.direction,
-                },
-            )
-        })
-        .collect())
+    Ok(sorted_choices(
+        data::effective_fields(project, *record)
+            .into_iter()
+            .map(|field| {
+                named_choice(
+                    project,
+                    data::CarriedFieldPath {
+                        item: entry.item,
+                        path: path.clone(),
+                        field: field.id,
+                        direction: entry.direction,
+                    },
+                )
+            })
+            .collect(),
+    ))
 }
 
 #[cfg(test)]
@@ -482,4 +513,33 @@ pub(crate) mod tests {
                 .contains("128")
         );
     }
+    #[test]
+    fn recursive_picker_starts_with_distinct_leaf_names_and_sorts_them() {
+        let (f, next) = recursive_payload();
+        let exchange = &f.project.relations[&f.exchange];
+        let context = FieldPathKey {
+            path: vec![f.origin, next, next],
+            field: next,
+        };
+        let visible = children(&f.project, exchange, &MessageKind::Call, &context).unwrap();
+        let leaf = visible
+            .iter()
+            .find(|choice| choice.key.field == f.leaf)
+            .unwrap();
+        assert!(leaf.to_string().starts_with("latitude (@latitude)"));
+        assert!(leaf.label.contains("origin (@origin) → next (@next)"));
+        assert!(
+            visible.windows(2).all(
+                |pair| pair[0].to_string().to_lowercase() <= pair[1].to_string().to_lowercase()
+            )
+        );
+        assert_ne!(
+            visible[0].to_string().chars().take(24).collect::<String>(),
+            visible[1].to_string().chars().take(24).collect::<String>()
+        );
+        assert_eq!(
+            resolve(&f.project, exchange, &MessageKind::Call, &leaf.key),
+            Some(leaf.clone())
+        );
+    }
 }

crates/oa-desktop/src/forms/data_fields.rs

@@ -363,6 +363,10 @@ fn message_value<'a>(
             {
                 out = out.push(text("Current address needs review. Choose an explicit path to resolve a legacy, ambiguous or incompatible value.").size(11).color(style::MUTED));
                 let retained = crate::data_values::FieldPathChoice {
+                    picker_label: format!(
+                        "{} · current address needs review",
+                        project.named(key.field)
+                    ),
                     label: format!(
                         "Current address · {} / {}",
                         key.path
@@ -377,6 +381,9 @@ fn message_value<'a>(
                 selected = Some(retained.clone());
                 choices.push(retained);
             }
+            if let Some(choice) = &selected {
+                out = out.push(text(choice.label.clone()).size(11).color(style::MUTED));
+            }
             let owned = path.to_owned();
             out = out.push(
                 pick_list(choices, selected, move |choice| {