This trivial patch adds a regression test for CASE expressions that use

an untyped literal in the CASE's test expression. This adds test
coverage for a bug that was fixed by Tom on January 12.

src/test/regress/expected/case.out

@@ -72,6 +72,13 @@ SELECT '6' AS "One",
  6   |                     6
 (1 row)
 
+-- Test for cases involving untyped literals in test expression
+SELECT CASE 'a' WHEN 'a' THEN 1 ELSE 2 END;
+ case 
+------
+    1
+(1 row)
+
 --
 -- Examples of targets involving tables
 --

src/test/regress/sql/case.sql

@@ -58,6 +58,9 @@ SELECT '6' AS "One",
     ELSE 7
   END AS "Two WHEN with default";
 
+-- Test for cases involving untyped literals in test expression
+SELECT CASE 'a' WHEN 'a' THEN 1 ELSE 2 END;
+
 --
 -- Examples of targets involving tables
 --