fix(agtype): coerce item to agtype in IN operator to support edge/vertex membership

regress/expected/expr.out

@@ -319,6 +319,50 @@ $$RETURN 1 IN [[null]]$$) AS r(c boolean);
  f
 (1 row)
 
+-- edge/vertex IN relationships()/nodes() (issue #2542 regression)
+SELECT * FROM create_graph('expr_in_op');
+NOTICE:  graph "expr_in_op" has been created
+ create_graph 
+--------------
+
+(1 row)
+
+SELECT * FROM cypher('expr_in_op',
+$$CREATE (a:L)-[:R]->(b)$$) AS r(c agtype);
+ c 
+---
+(0 rows)
+
+SELECT * FROM cypher('expr_in_op',
+$$MATCH ()-[r0]->()
+MATCH p0 = (:L)-[:R]->()
+RETURN r0 IN relationships(p0)$$) AS r(c boolean);
+ c 
+---
+ t
+(1 row)
+
+SELECT * FROM cypher('expr_in_op',
+$$MATCH (a:L)
+MATCH p0 = (:L)-[:R]->()
+RETURN a IN nodes(p0)$$) AS r(c boolean);
+ c 
+---
+ t
+(1 row)
+
+SELECT * FROM drop_graph('expr_in_op', true);
+NOTICE:  drop cascades to 4 other objects
+DETAIL:  drop cascades to table expr_in_op._ag_label_vertex
+drop cascades to table expr_in_op._ag_label_edge
+drop cascades to table expr_in_op."L"
+drop cascades to table expr_in_op."R"
+NOTICE:  graph "expr_in_op" has been dropped
+ drop_graph 
+------------
+
+(1 row)
+
 -- empty list: x IN [] should always return false
 SELECT * FROM cypher('expr',
 $$RETURN 1 IN []$$) AS r(c boolean);

regress/sql/expr.sql

@@ -157,6 +157,19 @@ SELECT * FROM cypher('expr',
 $$RETURN 1 in [[1]]$$) AS r(c boolean);
 SELECT * FROM cypher('expr',
 $$RETURN 1 IN [[null]]$$) AS r(c boolean);
+-- edge/vertex IN relationships()/nodes() (issue #2542 regression)
+SELECT * FROM create_graph('expr_in_op');
+SELECT * FROM cypher('expr_in_op',
+$$CREATE (a:L)-[:R]->(b)$$) AS r(c agtype);
+SELECT * FROM cypher('expr_in_op',
+$$MATCH ()-[r0]->()
+MATCH p0 = (:L)-[:R]->()
+RETURN r0 IN relationships(p0)$$) AS r(c boolean);
+SELECT * FROM cypher('expr_in_op',
+$$MATCH (a:L)
+MATCH p0 = (:L)-[:R]->()
+RETURN a IN nodes(p0)$$) AS r(c boolean);
+SELECT * FROM drop_graph('expr_in_op', true);
 -- empty list: x IN [] should always return false
 SELECT * FROM cypher('expr',
 $$RETURN 1 IN []$$) AS r(c boolean);

src/backend/utils/adt/agtype.c

@@ -4976,13 +4976,14 @@ Datum agtype_in_operator(PG_FUNCTION_ARGS)
         agtv_arg = agtv_materialize_vle_edges(agt_arg);
         array_size = agtv_arg->val.array.num_elems;
 
-        /* return null if the item to find is null */
-        if (PG_ARGISNULL(1))
+        /* get the item to search for, with proper edge/vertex coercion */
+        agt_item = get_one_agtype_from_variadic_args(fcinfo, 1, 1);
+
+        /* return null if the item is null or an agtype null */
+        if (agt_item == NULL)
         {
             PG_RETURN_NULL();
         }
-        /* get the item to search for */
-        agt_item = AG_GET_ARG_AGTYPE_P(1);
 
         /* init item iterator */
         it_item = agtype_iterator_init(&agt_item->root);
@@ -5043,13 +5044,14 @@ Datum agtype_in_operator(PG_FUNCTION_ARGS)
 
         array_size = AGT_ROOT_COUNT(agt_arg);
 
-        /* return null if the item to find is null */
-        if (PG_ARGISNULL(1))
+        /* get the item to search for, with proper edge/vertex coercion */
+        agt_item = get_one_agtype_from_variadic_args(fcinfo, 1, 1);
+
+        /* return null if the item is null or an agtype null */
+        if (agt_item == NULL)
         {
             PG_RETURN_NULL();
         }
-        /* get the item to search for */
-        agt_item = AG_GET_ARG_AGTYPE_P(1);
 
         /* init item iterator */
         it_item = agtype_iterator_init(&agt_item->root);