Fix a number of places that produced XX000 errors in the regression tests.

It's against project policy to use elog() for user-facing errors, or to
omit an errcode() selection for errors that aren't supposed to be "can't
happen" cases.  Fix all the violations of this policy that result in
ERRCODE_INTERNAL_ERROR log entries during the standard regression tests,
as errors that can reliably be triggered from SQL surely should be
considered user-facing.

I also looked through all the files touched by this commit and fixed
other nearby problems of the same ilk.  I do not claim to have fixed
all violations of the policy, just the ones in these files.

In a few places I also changed existing ERRCODE choices that didn't
seem particularly appropriate; mainly replacing ERRCODE_SYNTAX_ERROR
by something more specific.

Back-patch to 9.5, but no further; changing ERRCODE assignments in
stable branches doesn't seem like a good idea.

1 files changed, 6 insertions, 2 deletions

diff --git a/src/backend/access/heap/heapam.c b/src/backend/access/heap/heapam.c
index 050efdc4806..3701d8e59d5 100644
--- a/src/backend/access/heap/heapam.c
+++ b/src/backend/access/heap/heapam.c
@@ -2801,7 +2801,9 @@ l1:
 	if (result == HeapTupleInvisible)
 	{
 		UnlockReleaseBuffer(buffer);
-		elog(ERROR, "attempted to delete invisible tuple");
+		ereport(ERROR,
+				(errcode(ERRCODE_OBJECT_NOT_IN_PREREQUISITE_STATE),
+				 errmsg("attempted to delete invisible tuple")));
 	}
 	else if (result == HeapTupleBeingUpdated && wait)
 	{
@@ -3343,7 +3345,9 @@ l2:
 	if (result == HeapTupleInvisible)
 	{
 		UnlockReleaseBuffer(buffer);
-		elog(ERROR, "attempted to update invisible tuple");
+		ereport(ERROR,
+				(errcode(ERRCODE_OBJECT_NOT_IN_PREREQUISITE_STATE),
+				 errmsg("attempted to update invisible tuple")));
 	}
 	else if (result == HeapTupleBeingUpdated && wait)
 	{