Use the Postgres way to get the version number

Unsurprisingly, there was one.

lib/pg_repack.sql.in

@@ -16,30 +16,6 @@ CREATE FUNCTION repack.version_sql() RETURNS text AS
 $$SELECT 'pg_repack REPACK_VERSION'::text$$
 LANGUAGE SQL IMMUTABLE STRICT;
 
-CREATE FUNCTION repack.pg_version(version_str text DEFAULT NULL) RETURNS integer
-AS $$
-    -- Return the server version number in a format similar to PG_VERSION_NUM.
-    -- Call with no argument for the server version, pass an argument for testing
-    select (case
-        when array_length(tokens, 1) = 2 then
-            to_char(tokens[1], 'FM00') ||
-            '00' || to_char(tokens[2], 'FM00')
-        when array_length(tokens, 1) = 3 then
-            to_char(tokens[1], 'FM00') ||
-            to_char(tokens[2], 'FM00') ||
-            to_char(tokens[3], 'FM00')
-        else
-            -- This will raise an error which we can read
-            'unexpected version string: ' || coalesce($1, version())
-    end)::int
-    from (
-        select string_to_array(substring(
-            split_part(coalesce($1, version()), ' ', 2)
-            from '\d+\.\d+(?:\.\d+)?'), '.')::int[]
-    ) as x (tokens);
-$$
-LANGUAGE SQL IMMUTABLE;
-
 CREATE AGGREGATE repack.array_accum (
     sfunc = array_append,
     basetype = anyelement,

regress/expected/repack.out

@@ -12,7 +12,7 @@ select filename from (values
     (100000, 100003, 'repack_2.out'),
     (100003, 110000, 'repack_3.out')
 ) as x (min, max, filename)
-where min <= repack.pg_version() and repack.pg_version() < max;
+where current_setting('server_version_num')::int between min and max - 1;
   filename  
 ------------
  repack.out

regress/expected/repack_1.out

@@ -12,7 +12,7 @@ select filename from (values
     (100000, 100003, 'repack_2.out'),
     (100003, 110000, 'repack_3.out')
 ) as x (min, max, filename)
-where min <= repack.pg_version() and repack.pg_version() < max;
+where current_setting('server_version_num')::int between min and max - 1;
    filename   
 --------------
  repack_1.out

regress/expected/repack_2.out

@@ -12,7 +12,7 @@ select filename from (values
     (100000, 100003, 'repack_2.out'),
     (100003, 110000, 'repack_3.out')
 ) as x (min, max, filename)
-where min <= repack.pg_version() and repack.pg_version() < max;
+where current_setting('server_version_num')::int between min and max - 1;
    filename   
 --------------
  repack_2.out

regress/expected/repack_3.out

@@ -12,7 +12,7 @@ select filename from (values
     (100000, 100003, 'repack_2.out'),
     (100003, 110000, 'repack_3.out')
 ) as x (min, max, filename)
-where min <= repack.pg_version() and repack.pg_version() < max;
+where current_setting('server_version_num')::int between min and max - 1;
    filename   
 --------------
  repack_3.out

regress/expected/repack_4.out

@@ -12,7 +12,7 @@ select filename from (values
     (100000, 100003, 'repack_2.out'),
     (100003, 110000, 'repack_3.out')
 ) as x (min, max, filename)
-where min <= repack.pg_version() and repack.pg_version() < max;
+where current_setting('server_version_num')::int between min and max - 1;
    filename   
 --------------
  repack_4.out

regress/expected/repack_5.out

@@ -12,7 +12,7 @@ select filename from (values
     (100000, 100003, 'repack_2.out'),
     (100003, 110000, 'repack_3.out')
 ) as x (min, max, filename)
-where min <= repack.pg_version() and repack.pg_version() < max;
+where current_setting('server_version_num')::int between min and max - 1;
    filename   
 --------------
  repack_5.out

regress/expected/repack_6.out

@@ -12,7 +12,7 @@ select filename from (values
     (100000, 100003, 'repack_2.out'),
     (100003, 110000, 'repack_3.out')
 ) as x (min, max, filename)
-where min <= repack.pg_version() and repack.pg_version() < max;
+where current_setting('server_version_num')::int between min and max - 1;
    filename   
 --------------
  repack_6.out

regress/sql/repack.sql

@@ -12,7 +12,7 @@ select filename from (values
     (100000, 100003, 'repack_2.out'),
     (100003, 110000, 'repack_3.out')
 ) as x (min, max, filename)
-where min <= repack.pg_version() and repack.pg_version() < max;
+where current_setting('server_version_num')::int between min and max - 1;
 
 SET client_min_messages = warning;
 --