Fix serialization of holds_over_chain clauses with fastobo

Author: althonos

pronto/serializers/_fastobo.py

@@ -205,7 +205,8 @@ def _to_typedef_frame(self, relationship: Relationship):
         if r.builtin:
             frame.append(fastobo.typedef.BuiltinClause(True))
         for chain in sorted(r.holds_over_chain):
-            frame.append(fastobo.typedef.HoldsOverChainClause(*chain))
+            c1, c2 = map(fastobo.id.parse, chain)
+            frame.append(fastobo.typedef.HoldsOverChainClause(c1, c2))
         if r.antisymmetric:
             frame.append(fastobo.typedef.IsAntiSymmetricClause(True))
         if r.cyclic:

tests/test_issues.py

@@ -136,3 +136,12 @@ def test_metadata_tag_serialization(self):
             is_metadata_tag: true
             """).strip()
         )
+
+    def test_relationship_chains(self):
+        ont = pronto.Ontology()
+        r1 = ont.create_relationship("r1")
+        r2 = ont.create_relationship("r2")
+        r3 = ont.create_relationship("r3")
+        r3.holds_over_chain = { (r1, r2) }
+        r3.equivalent_to_chain = { (r1, r2) }
+        ont.dumps()