Add shortest_path / all_shortest_paths SRFs

Makefile

@@ -166,6 +166,7 @@ REGRESS = scan \
           cypher_delete \
           cypher_with \
           cypher_vle \
+          age_shortest_path \
           cypher_union \
           cypher_call \
           cypher_merge \

age--1.7.0--y.y.y.sql

@@ -537,6 +537,37 @@ CALLED ON NULL INPUT
 PARALLEL UNSAFE
 AS 'MODULE_PATHNAME';
 
+-- Unweighted (hop-count) shortest path between two vertices, computed over the
+-- cached global graph adjacency via BFS. Returns a single path (0 or 1 rows).
+-- Argument order mirrors the Cypher shortestPath() pattern
+-- (a)-[:type*min_hops..max_hops]->(b):
+--   (graph_name, start, end, edge_types, direction, min_hops, max_hops)
+CREATE FUNCTION ag_catalog.age_shortest_path(IN agtype, IN agtype, IN agtype,
+                                             IN agtype DEFAULT NULL,
+                                             IN agtype DEFAULT NULL,
+                                             IN agtype DEFAULT NULL,
+                                             IN agtype DEFAULT NULL)
+    RETURNS SETOF agtype
+LANGUAGE C
+STABLE
+CALLED ON NULL INPUT
+PARALLEL UNSAFE
+AS 'MODULE_PATHNAME';
+
+-- All unweighted shortest paths between two vertices (one path per row).
+-- Same argument order as age_shortest_path.
+CREATE FUNCTION ag_catalog.age_all_shortest_paths(IN agtype, IN agtype, IN agtype,
+                                                  IN agtype DEFAULT NULL,
+                                                  IN agtype DEFAULT NULL,
+                                                  IN agtype DEFAULT NULL,
+                                                  IN agtype DEFAULT NULL)
+    RETURNS SETOF agtype
+LANGUAGE C
+STABLE
+CALLED ON NULL INPUT
+PARALLEL UNSAFE
+AS 'MODULE_PATHNAME';
+
 --
 -- Composite types for vertex and edge
 --