Make contrib/tablefunc crosstab() also check typmod

contrib/tablefunc connectby() checks both type OID and typmod for
its output columns while crosstab() only checks type OID. Fix that
by makeing the crosstab() check look more like the connectby() check.

Reported-by: Tom Lane
Reviewed-by: Tom Lane
Discussion: https://postgr.es/m/flat/18937.1709676295%40sss.pgh.pa.us

contrib/tablefunc/tablefunc.c

@@ -1527,10 +1527,10 @@ static void
 compatCrosstabTupleDescs(TupleDesc ret_tupdesc, TupleDesc sql_tupdesc)
 {
 	int			i;
-	Form_pg_attribute ret_attr;
 	Oid			ret_atttypid;
-	Form_pg_attribute sql_attr;
 	Oid			sql_atttypid;
+	int32		ret_atttypmod;
+	int32		sql_atttypmod;
 
 	if (ret_tupdesc->natts < 2)
 		ereport(ERROR,
@@ -1539,34 +1539,40 @@ compatCrosstabTupleDescs(TupleDesc ret_tupdesc, TupleDesc sql_tupdesc)
 				 errdetail("Return row must have at least two columns.")));
 	Assert(sql_tupdesc->natts == 3);	/* already checked by caller */
 
-	/* check the rowid types match */
+	/* check the row_name types match */
 	ret_atttypid = TupleDescAttr(ret_tupdesc, 0)->atttypid;
 	sql_atttypid = TupleDescAttr(sql_tupdesc, 0)->atttypid;
-	if (ret_atttypid != sql_atttypid)
+	ret_atttypmod = TupleDescAttr(ret_tupdesc, 0)->atttypmod;
+	sql_atttypmod = TupleDescAttr(sql_tupdesc, 0)->atttypmod;
+	if (ret_atttypid != sql_atttypid ||
+		(ret_atttypmod >= 0 && ret_atttypmod != sql_atttypmod))
 		ereport(ERROR,
 				(errcode(ERRCODE_DATATYPE_MISMATCH),
 				 errmsg("invalid crosstab return type"),
 				 errdetail("Source row_name datatype %s does not match return row_name datatype %s.",
-						   format_type_be(sql_atttypid),
-						   format_type_be(ret_atttypid))));
+						   format_type_with_typemod(sql_atttypid, sql_atttypmod),
+						   format_type_with_typemod(ret_atttypid, ret_atttypmod))));
 
 	/*
-	 * - attribute [1] of the sql tuple is the category; no need to check it -
-	 * attribute [2] of the sql tuple should match attributes [1] to [natts]
+	 * attribute [1] of sql tuple is the category; no need to check it
+	 * attribute [2] of sql tuple should match attributes [1] to [natts - 1]
 	 * of the return tuple
 	 */
-	sql_attr = TupleDescAttr(sql_tupdesc, 2);
+	sql_atttypid = TupleDescAttr(sql_tupdesc, 2)->atttypid;
+	sql_atttypmod = TupleDescAttr(sql_tupdesc, 2)->atttypmod;
 	for (i = 1; i < ret_tupdesc->natts; i++)
 	{
-		ret_attr = TupleDescAttr(ret_tupdesc, i);
+		ret_atttypid = TupleDescAttr(ret_tupdesc, i)->atttypid;
+		ret_atttypmod = TupleDescAttr(ret_tupdesc, i)->atttypmod;
 
-		if (ret_attr->atttypid != sql_attr->atttypid)
+		if (ret_atttypid != sql_atttypid ||
+			(ret_atttypmod >= 0 && ret_atttypmod != sql_atttypmod))
 			ereport(ERROR,
 					(errcode(ERRCODE_DATATYPE_MISMATCH),
 					 errmsg("invalid crosstab return type"),
 					 errdetail("Source value datatype %s does not match return value datatype %s in column %d.",
-							   format_type_be(sql_attr->atttypid),
-							   format_type_be(ret_attr->atttypid),
+							   format_type_with_typemod(sql_atttypid, sql_atttypmod),
+							   format_type_with_typemod(ret_atttypid, ret_atttypmod),
 							   i + 1)));
 	}