contrib/xml2: Use SQL-standard function bodies.

In the same spirit as 969bbd0fa, 13e3796c9, 3f323eba8.

Tom Lane and Ronan Dunklau

Discussion: https://postgr.es/m/3316564.aeNJFYEL58@aivenlaptop

contrib/xml2/Makefile

@@ -7,7 +7,9 @@ OBJS = \
 	xslt_proc.o
 
 EXTENSION = xml2
-DATA = xml2--1.1.sql xml2--1.0--1.1.sql
+DATA = xml2--1.1.sql \
+	xml2--1.1--1.2.sql \
+	xml2--1.0--1.1.sql
 PGFILEDESC = "xml2 - XPath querying and XSLT"
 
 REGRESS = xml2

contrib/xml2/meson.build

@@ -27,6 +27,7 @@ contrib_targets += xml2
 install_data(
   'xml2--1.0--1.1.sql',
   'xml2--1.1.sql',
+  'xml2--1.1--1.2.sql',
   'xml2.control',
   kwargs: contrib_data_args,
 )

contrib/xml2/xml2--1.1--1.2.sql

@@ -0,0 +1,18 @@
+/* contrib/xml2/xml2--1.1--1.2.sql */
+
+-- complain if script is sourced in psql, rather than via ALTER EXTENSION
+\echo Use "ALTER EXTENSION xml2 UPDATE TO '1.2'" to load this file. \quit
+
+CREATE OR REPLACE FUNCTION xpath_list(text,text) RETURNS text
+LANGUAGE SQL STRICT IMMUTABLE PARALLEL SAFE
+RETURN xpath_list($1, $2, ','::text);
+
+CREATE OR REPLACE FUNCTION xpath_nodeset(text,text)
+RETURNS text
+LANGUAGE SQL STRICT IMMUTABLE PARALLEL SAFE
+RETURN xpath_nodeset($1, $2, ''::text, ''::text);
+
+CREATE OR REPLACE FUNCTION xpath_nodeset(text,text,text)
+RETURNS text
+LANGUAGE SQL STRICT IMMUTABLE PARALLEL SAFE
+RETURN xpath_nodeset($1, $2, ''::text, $3);

contrib/xml2/xml2.control

@@ -1,6 +1,6 @@
 # xml2 extension
 comment = 'XPath querying and XSLT'
-default_version = '1.1'
+default_version = '1.2'
 module_pathname = '$libdir/pgxml'
 # XXX do we still need this to be non-relocatable?
 relocatable = false