FOR PORTION OF gram.y target_location seems wrong

Hi.

| FOR PORTION OF ColId FROM a_expr TO a_expr
{
ForPortionOfClause *n = makeNode(ForPortionOfClause);
n->range_name = $4;
n->location = @4;
n->target_start = $6;
n->target_end = $8;
n->target_location = @5;
$$ = (Node *) n;
}

n->target_location = @5;

Should be

n->target_location = @6;

It's not reachable because of queries like:

UPDATE for_portion_of_test
FOR PORTION OF valid_at FROM NULL TO NULL
SET name = 'NULL to NULL';

won't reach
ereport(ERROR,
(errmsg("FOR PORTION OF target was null")),
executor_errposition(estate, forPortionOf->targetLocation));

typedef struct ForPortionOfClause
{
NodeTag type;
char *range_name; /* column name of the range/multirange */
ParseLoc location; /* token location, or -1 if unknown */
ParseLoc target_location; /* token location, or -1 if unknown */
Node *target; /* Expr from FOR PORTION OF col
(...) syntax */
Node *target_start; /* Expr from FROM ... TO ... syntax */
Node *target_end; /* Expr from FROM ... TO ... syntax */
} ForPortionOfClause;

Generally, we place ParseLoc at the end of the node, putting it
elsewhere should be fine.
But here, we have two comments, ``/* token location, or -1 if unknown */``.
The "token" is ambiguous, perhaps it's worth the trouble to enhance it?

--
jian
https://www.enterprisedb.com/