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diff --git a/src/test/perl/PostgresVersion.pm b/src/test/perl/PostgresVersion.pm
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+############################################################################
+#
+# PostgresVersion.pm
+#
+# Module encapsulating Postgres Version numbers
+#
+# Copyright (c) 2021, PostgreSQL Global Development Group
+#
+############################################################################
+
+=pod
+
+=head1 NAME
+
+PostgresVersion - class representing PostgreSQL version numbers
+
+=head1 SYNOPSIS
+
+  use PostgresVersion;
+
+  my $version = PostgresVersion->new($version_arg);
+
+  # compare two versions
+  my $bool = $version1 <= $version2;
+
+  # or compare with a number
+  $bool = $version < 12;
+
+  # or with a string
+  $bool = $version lt "13.1";
+
+  # interpolate in a string
+  my $stringyval = "version: $version";
+
+=head1 DESCRIPTION
+
+PostgresVersion encapsulates Postgres version numbers, providing parsing
+of common version formats and comparison operations.
+
+=cut
+
+package PostgresVersion;
+
+use strict;
+use warnings;
+
+use Scalar::Util qw(blessed);
+
+use overload
+  '<=>' => \&_version_cmp,
+  'cmp' => \&_version_cmp,
+  '""'  => \&_stringify;
+
+=pod
+
+=head1 METHODS
+
+=over
+
+=item PostgresVersion->new($version)
+
+Create a new PostgresVersion instance.
+
+The argument can be a number like 12, or a string like '12.2' or the output
+of a Postgres command like `psql --version` or `pg_config --version`;
+
+=back
+
+=cut
+
+sub new
+{
+	my $class = shift;
+	my $arg   = shift;
+
+	chomp $arg;
+
+	# Accept standard formats, in case caller has handed us the output of a
+	# postgres command line tool
+	my $devel;
+	($arg, $devel) = ($1, $2)
+	  if (
+		$arg =~ m!^                             # beginning of line
+          (?:\(?PostgreSQL\)?\s)?         # ignore PostgreSQL marker
+          (\d+(?:\.\d+)*)                 # version number, dotted notation
+          (devel|(?:alpha|beta|rc)\d+)?   # dev marker - see version_stamp.pl
+		 !x);
+
+	# Split into an array
+	my @numbers = split(/\./, $arg);
+
+	# Treat development versions as having a minor/micro version one less than
+	# the first released version of that branch.
+	push @numbers, -1 if ($devel);
+
+	$devel ||= "";
+
+	return bless { str => "$arg$devel", num => \@numbers }, $class;
+}
+
+# Routine which compares the _pg_version_array obtained for the two
+# arguments and returns -1, 0, or 1, allowing comparison between two
+# PostgresVersion objects or a PostgresVersion and a version string or number.
+#
+# If the second argument is not a blessed object we call the constructor
+# to make one.
+#
+# Because we're overloading '<=>' and 'cmp' this function supplies us with
+# all the comparison operators ('<' and friends, 'gt' and friends)
+#
+sub _version_cmp
+{
+	my ($a, $b, $swapped) = @_;
+
+	$b = __PACKAGE__->new($b) unless blessed($b);
+
+	($a, $b) = ($b, $a) if $swapped;
+
+	my ($an, $bn) = ($a->{num}, $b->{num});
+
+	for (my $idx = 0;; $idx++)
+	{
+		return 0 unless (defined $an->[$idx] && defined $bn->[$idx]);
+		return $an->[$idx] <=> $bn->[$idx]
+		  if ($an->[$idx] <=> $bn->[$idx]);
+	}
+}
+
+# Render the version number using the saved string.
+sub _stringify
+{
+	my $self = shift;
+	return $self->{str};
+}
+
+1;