Fix: do not allow base and constant sets to have children

rsconcept/backend/apps/rsform/models/api_RSForm.py

@@ -506,7 +506,12 @@ class SemanticInfo:
         sources = self._extract_sources(target)
         if len(sources) != 1:
             return target.id
-        return next(iter(sources))
+
+        parent_id = next(iter(sources))
+        parent = self._cst_by_ID[parent_id]
+        if is_base_set(parent.cst_type):
+            return target.id
+        return parent_id
 
     def _extract_sources(self, target: Constituenta) -> set[int]:
         sources: set[int] = set()

rsconcept/backend/apps/rsform/tests/s_models/t_RSForm.py

@@ -259,6 +259,10 @@ class TestRSForm(TestCase):
             alias='D4',
             definition_formal=r'Pr2(D3)',
         )
+        f2 = self.schema.insert_new(
+            alias='F2',
+            definition_formal=r'[α∈ℬ(X1)] X1\α',
+        )
         
         self.schema.restore_order()
         x1.refresh_from_db()
@@ -271,6 +275,7 @@ class TestRSForm(TestCase):
         d3.refresh_from_db()
         d4.refresh_from_db()
         f1.refresh_from_db()
+        f2.refresh_from_db()
         a1.refresh_from_db()
 
         self.assertEqual(x1.order, 1)
@@ -284,6 +289,7 @@ class TestRSForm(TestCase):
         self.assertEqual(d4.order, 9)
         self.assertEqual(d2.order, 10)
         self.assertEqual(f1.order, 11)
+        self.assertEqual(f2.order, 12)
 
 
     def test_reset_aliases(self):

rsconcept/frontend/src/models/RSFormLoader.ts

@@ -103,7 +103,12 @@ export class RSFormLoader {
     if (sources.size !== 1 || sources.has(target.id)) {
       return undefined;
     }
-    return sources.values().next().value as ConstituentaID;
+    const parent_id = sources.values().next().value as ConstituentaID;
+    const parent = this.cstByID.get(parent_id);
+    if (parent && isBaseSet(parent.cst_type)) {
+      return undefined;
+    }
+    return parent_id;
   }
 
   private extractSources(target: IConstituenta): Set<ConstituentaID> {