Fix oversight in new code for printing rangetable aliases.

In commit 11e131854f8231a21613f834c40fe9d046926387, I missed the case of
a CTE RTE that doesn't have a user-defined alias, but does have an
alias assigned by set_rtable_names().  Per report from Peter Eisentraut.

While at it, refactor slightly to reduce code duplication.

2 files changed, 35 insertions, 0 deletions

diff --git a/src/test/regress/expected/with.out b/src/test/regress/expected/with.out
index 671f293b68d..b98ca630ee9 100644
--- a/src/test/regress/expected/with.out
+++ b/src/test/regress/expected/with.out
@@ -292,6 +292,30 @@ SELECT pg_get_viewdef('vsubdepartment'::regclass, true);
     FROM subdepartment;
 (1 row)
 
+-- Another reverse-listing example
+CREATE VIEW sums_1_100 AS
+WITH RECURSIVE t(n) AS (
+    VALUES (1)
+UNION ALL
+    SELECT n+1 FROM t WHERE n < 100
+)
+SELECT sum(n) FROM t;
+\d+ sums_1_100
+              View "public.sums_1_100"
+ Column |  Type  | Modifiers | Storage | Description 
+--------+--------+-----------+---------+-------------
+ sum    | bigint |           | plain   | 
+View definition:
+ WITH RECURSIVE t(n) AS (
+                 VALUES (1)
+        UNION ALL 
+                 SELECT t_1.n + 1
+                   FROM t t_1
+                  WHERE t_1.n < 100
+        )
+ SELECT sum(t.n) AS sum
+   FROM t;
+
 -- corner case in which sub-WITH gets initialized first
 with recursive q as (
       select * from department
diff --git a/src/test/regress/sql/with.sql b/src/test/regress/sql/with.sql
index 609f51b0c95..4ff852736bc 100644
--- a/src/test/regress/sql/with.sql
+++ b/src/test/regress/sql/with.sql
@@ -178,6 +178,17 @@ SELECT * FROM vsubdepartment ORDER BY name;
 SELECT pg_get_viewdef('vsubdepartment'::regclass);
 SELECT pg_get_viewdef('vsubdepartment'::regclass, true);
 
+-- Another reverse-listing example
+CREATE VIEW sums_1_100 AS
+WITH RECURSIVE t(n) AS (
+    VALUES (1)
+UNION ALL
+    SELECT n+1 FROM t WHERE n < 100
+)
+SELECT sum(n) FROM t;
+
+\d+ sums_1_100
+
 -- corner case in which sub-WITH gets initialized first
 with recursive q as (
       select * from department