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#!./perl -T
#
# All the tests in this file are ones that run exceptionally slowly
# (each test taking seconds or even minutes) in the absence of particular
# optimisations. Thus it is a sort of canary for optimisations being
# broken.
#
# Although it includes a watchdog timeout, this is set to a generous limit
# to allow for running on slow systems; therefore a broken optimisation
# might be indicated merely by this test file taking unusually long to
# run, rather than actually timing out.
#
# This is similar to t/perf/speed.t but tests performance regressions specific
# to taint.
#
BEGIN {
chdir 't' if -d 't';
@INC = ('../lib');
require Config; import Config;
require './test.pl';
skip_all_if_miniperl("No Scalar::Util under miniperl");
if (exists($Config{taint_support}) && !$Config{taint_support}) {
skip_all("built without taint support");
}
}
use strict;
use Scalar::Util qw(tainted);
$| = 1;
plan tests => 4;
watchdog(60);
my $taint = substr($ENV{PATH}, 0, 0); # and empty tainted string
{
my $in = $taint . ( "ab" x 200_000 );
utf8::upgrade($in);
ok(tainted($in), "performance issue only when tainted");
while ($in =~ /\Ga+b/g) { }
pass("\\G on tainted string");
}
# RT #130584
# tainted string caused the utf8 pos cache to be cleared each time
{
my $repeat = 30_000;
my $in = $taint . ("abcdefghijklmnopqrstuvwxyz" x $repeat);
utf8::upgrade($in);
ok(tainted($in), "performance issue only when tainted");
local ${^UTF8CACHE} = 1; # defeat debugging
for my $i (1..$repeat) {
$in =~ /abcdefghijklmnopqrstuvwxyz/g or die;
my $p = pos($in); # this was slow
}
pass("RT #130584 pos on tainted utf8 string");
}
1;