Fix issue #945 unaliased match clause giving incorrect results in count

regress/expected/cypher_match.out

@@ -2119,6 +2119,43 @@ SELECT * FROM cypher('cypher_match', $$MATCH ({n0:0}) MATCH ()-[]->() MATCH ({n1
 ---
 (0 rows)
 
+--
+-- issue#945 : un-aliased match clauses should be included in output node
+--
+SELECT * from cypher('cypher_match', $$ CREATE (a:label1 {id: '1'}), (b:label1 {id: '2'})$$) as (a agtype);
+ a 
+---
+(0 rows)
+
+SELECT * from cypher('cypher_match', $$ CREATE (a:label2 {id: '1'}), (b:label2 {id: '2'})$$) as (a agtype);
+ a 
+---
+(0 rows)
+
+SELECT * from cypher('cypher_match', $$ MATCH (:label1) RETURN count(*) $$) as (result agtype);
+ result 
+--------
+ 2
+(1 row)
+
+SELECT * from cypher('cypher_match', $$ MATCH (:label1),(:label2) RETURN count(*) $$) as (result agtype);
+ result 
+--------
+ 4
+(1 row)
+
+SELECT * from cypher('cypher_match', $$ MATCH (a:label1),(:label2) RETURN count(*) $$) as (result agtype);
+ result 
+--------
+ 4
+(1 row)
+
+SELECT * from cypher('cypher_match', $$ MATCH (:label1),(a:label2) RETURN count(*) $$) as (result agtype);
+ result 
+--------
+ 4
+(1 row)
+
 --
 -- self referencing property constraints (issue #898)
 --
@@ -2178,7 +2215,7 @@ SELECT * FROM cypher('cypher_match', $$ CREATE () WITH * MATCH (x{n0:x.n1}) RETU
 -- Clean up
 --
 SELECT drop_graph('cypher_match', true);
-NOTICE:  drop cascades to 17 other objects
+NOTICE:  drop cascades to 19 other objects
 DETAIL:  drop cascades to table cypher_match._ag_label_vertex
 drop cascades to table cypher_match._ag_label_edge
 drop cascades to table cypher_match.v
@@ -2196,6 +2233,8 @@ drop cascades to table cypher_match.other_v
 drop cascades to table cypher_match.opt_match_v
 drop cascades to table cypher_match.opt_match_e
 drop cascades to table cypher_match.knows
+drop cascades to table cypher_match.label1
+drop cascades to table cypher_match.label2
 NOTICE:  graph "cypher_match" has been dropped
  drop_graph 
 ------------

regress/sql/cypher_match.sql

@@ -964,6 +964,17 @@ SELECT * FROM cypher('cypher_match', $$ MATCH (_age_default_whatever) RETURN 0 $
 SELECT * FROM cypher('cypher_match', $$ MATCH ({name: "Dave"}) MATCH ({name: "Dave"}) MATCH ({name: "Dave"}) RETURN 0 $$) as (a agtype);
 SELECT * FROM cypher('cypher_match', $$MATCH ({n0:0}) MATCH ()-[]->() MATCH ({n1:0})-[]-() RETURN 0 AS n2$$) as (a agtype);
 
+--
+-- issue#945 : un-aliased match clauses should be included in output node
+--
+SELECT * from cypher('cypher_match', $$ CREATE (a:label1 {id: '1'}), (b:label1 {id: '2'})$$) as (a agtype);
+SELECT * from cypher('cypher_match', $$ CREATE (a:label2 {id: '1'}), (b:label2 {id: '2'})$$) as (a agtype);
+SELECT * from cypher('cypher_match', $$ MATCH (:label1) RETURN count(*) $$) as (result agtype);
+SELECT * from cypher('cypher_match', $$ MATCH (:label1),(:label2) RETURN count(*) $$) as (result agtype);
+SELECT * from cypher('cypher_match', $$ MATCH (a:label1),(:label2) RETURN count(*) $$) as (result agtype);
+SELECT * from cypher('cypher_match', $$ MATCH (:label1),(a:label2) RETURN count(*) $$) as (result agtype);
+
+
 --
 -- self referencing property constraints (issue #898)
 --

src/backend/parser/cypher_clause.c

@@ -91,9 +91,10 @@
  *      1. the node is in a path variable
  *      2. the node is a variable
  *      3. the node contains filter properties
+ *      4. the node has a valid label
  */
 #define INCLUDE_NODE_IN_JOIN_TREE(path, node) \
-    (path->var_name || node->name || node->props)
+    (path->var_name || node->name || node->props || node->label )
 
 typedef Query *(*transform_method)(cypher_parsestate *cpstate,
                                    cypher_clause *clause);
@@ -3805,7 +3806,7 @@ static List *transform_match_entities(cypher_parsestate *cpstate, Query *query,
             }
 
             /* should we make the node available */
-            output_node = (special_VLE_case && !node->name && !node->props) ?
+            output_node = (special_VLE_case && !node->name && !node->props && !valid_label) ?
                           false :
                           INCLUDE_NODE_IN_JOIN_TREE(path, node);