Fix handling of strict non-set functions with NULLs in set-valued inputs.

In a construct like "select plain_function(set_returning_function(...))",
the plain function is applied to each output row of the SRF successively.
If some of the SRF outputs are NULL, and the plain function is strict,
you'd expect to get NULL results for such rows ... but what actually
happened was that such rows were omitted entirely from the result set.
This was due to confusion of this case with what should happen for nested
set-returning functions; a strict SRF is indeed supposed to yield an empty
set for null input.  Per bug #8150 from Erwin Brandstetter.

Although this has been broken forever, we're not back-patching because
of the possibility that some apps out there expect the incorrect behavior.
This change should be listed as a possible incompatibility in the 9.3
release notes.

2 files changed, 10 insertions, 0 deletions

diff --git a/src/test/regress/expected/arrays.out b/src/test/regress/expected/arrays.out
index 051bac9234..76a8c56a76 100644
--- a/src/test/regress/expected/arrays.out
+++ b/src/test/regress/expected/arrays.out
@@ -1542,6 +1542,15 @@ select unnest(array[1,2,3,null,4,null,null,5,6]::text[]);
  6
 (9 rows)
 
+select abs(unnest(array[1,2,null,-3]));
+ abs 
+-----
+   1
+   2
+    
+   3
+(4 rows)
+
 select array_remove(array[1,2,2,3], 2);
  array_remove 
 --------------
diff --git a/src/test/regress/sql/arrays.sql b/src/test/regress/sql/arrays.sql
index 04e97254e1..e6df37216b 100644
--- a/src/test/regress/sql/arrays.sql
+++ b/src/test/regress/sql/arrays.sql
@@ -432,6 +432,7 @@ select unnest(array[1,2,3,4.5]::float8[]);
 select unnest(array[1,2,3,4.5]::numeric[]);
 select unnest(array[1,2,3,null,4,null,null,5,6]);
 select unnest(array[1,2,3,null,4,null,null,5,6]::text[]);
+select abs(unnest(array[1,2,null,-3]));
 select array_remove(array[1,2,2,3], 2);
 select array_remove(array[1,2,2,3], 5);
 select array_remove(array[1,NULL,NULL,3], NULL);