summaryrefslogtreecommitdiff
path: root/t/op/magic.t
blob: adbdad60d9522f029913ea36934f478166be14a2 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
#!./perl

BEGIN {
    $| = 1;
    chdir 't' if -d 't';
    @INC = '../lib';
    require './test.pl';
    plan (tests => 150);
}

# Test that defined() returns true for magic variables created on the fly,
# even before they have been created.
# This must come first, even before turning on warnings or setting up
# $SIG{__WARN__}, to avoid invalidating the tests.  warnings.pm currently
# does not mention any special variables, but that could easily change.
BEGIN {
    # not available in miniperl
    my %non_mini = map { $_ => 1 } qw(+ - [);
    for (qw(
	SIG ^OPEN ^TAINT ^UNICODE ^UTF8LOCALE ^WARNING_BITS 1 2 3 4 5 6 7 8
	9 42 & ` ' : ? ! _ - [ ^ ~ = % . ( ) < > \ / $ | + ; ] ^A ^C ^D
	^E ^F ^H ^I ^L ^N ^O ^P ^S ^T ^V ^W ^UTF8CACHE ::12345 main::98732
    )) {
	my $v = $_;
	# avoid using any global vars here:
	if ($v =~ s/^\^(?=.)//) {
	    for(substr $v, 0, 1) {
		$_ = chr ord() - 64;
	    }
	}
	SKIP:
	{
	    skip_if_miniperl("the module for *$_ may not be available in "
			     . "miniperl", 1) if $non_mini{$_};
	    ok defined *$v, "*$_ appears to be defined at the outset";
	}
    }
}

# This must be in a separate BEGIN block, as the mere mention of ${^TAINT}
# will invalidate the test for it.
BEGIN {
    $ENV{PATH} = '/bin' if ${^TAINT};
    $SIG{__WARN__} = sub { die "Dying on warning: ", @_ };
}

use warnings;
use Config;


$Is_MSWin32  = $^O eq 'MSWin32';
$Is_NetWare  = $^O eq 'NetWare';
$Is_VMS      = $^O eq 'VMS';
$Is_Dos      = $^O eq 'dos';
$Is_os2      = $^O eq 'os2';
$Is_Cygwin   = $^O eq 'cygwin';
$Is_MPE      = $^O eq 'mpeix';		
$Is_BeOS     = $^O eq 'beos';

$PERL = $ENV{PERL}
    || ($Is_NetWare           ? 'perl'   :
       $Is_VMS                ? $^X      :
       $Is_MSWin32            ? '.\perl' :
       './perl');

END {
    # On VMS, environment variable changes are peristent after perl exits
    delete $ENV{'FOO'} if $Is_VMS;
}

eval '$ENV{"FOO"} = "hi there";';	# check that ENV is inited inside eval
# cmd.exe will echo 'variable=value' but 4nt will echo just the value
# -- Nikola Knezevic
if ($Is_MSWin32)  { like `set FOO`, qr/^(?:FOO=)?hi there$/; }
elsif ($Is_VMS)   { is `write sys\$output f\$trnlnm("FOO")`, "hi there\n"; }
else              { is `echo \$FOO`, "hi there\n"; }

unlink_all 'ajslkdfpqjsjfk';
$! = 0;
open(FOO,'ajslkdfpqjsjfk');
isnt($!, 0);
close FOO; # just mention it, squelch used-only-once

SKIP: {
    skip('SIGINT not safe on this platform', 5)
	if $Is_MSWin32 || $Is_NetWare || $Is_Dos || $Is_MPE;
  # the next tests are done in a subprocess because sh spits out a
  # newline onto stderr when a child process kills itself with SIGINT.
  # We use a pipe rather than system() because the VMS command buffer
  # would overflow with a command that long.

    # For easy interpolation of test numbers:
    $next_test = curr_test() - 1;
    sub TIEARRAY {bless[]}
    sub FETCH { $next_test + pop }
    tie my @tn, __PACKAGE__;

    open( CMDPIPE, "| $PERL");

    print CMDPIPE "\$t1 = $tn[1]; \$t2 = $tn[2];\n", <<'END';

    $| = 1;		# command buffering

    $SIG{"INT"} = "ok1";     kill "INT",$$; sleep 1;
    $SIG{"INT"} = "IGNORE";  kill "INT",$$; sleep 1; print "ok $t2\n";
    $SIG{"INT"} = "DEFAULT"; kill "INT",$$; sleep 1; print" not ok $t2\n";

    sub ok1 {
	if (($x = pop(@_)) eq "INT") {
	    print "ok $t1\n";
	}
	else {
	    print "not ok $t1 ($x @_)\n";
	}
    }

END

    close CMDPIPE;

    open( CMDPIPE, "| $PERL");
    print CMDPIPE "\$t3 = $tn[3];\n", <<'END';

    { package X;
	sub DESTROY {
	    kill "INT",$$;
	}
    }
    sub x {
	my $x=bless [], 'X';
	return sub { $x };
    }
    $| = 1;		# command buffering
    $SIG{"INT"} = "ok3";
    {
	local $SIG{"INT"}=x();
	print ""; # Needed to expose failure in 5.8.0 (why?)
    }
    sleep 1;
    delete $SIG{"INT"};
    kill "INT",$$; sleep 1;
    sub ok3 {
	print "ok $t3\n";
    }
END
    close CMDPIPE;
    $? >>= 8 if $^O eq 'VMS'; # POSIX status hiding in 2nd byte
    my $todo = ($^O eq 'os2' ? ' # TODO: EMX v0.9d_fix4 bug: wrong nibble? ' : '');
    print $? & 0xFF ? "ok $tn[4]$todo\n" : "not ok $tn[4]$todo\n";

    open(CMDPIPE, "| $PERL");
    print CMDPIPE <<'END';

    sub PVBM () { 'foo' }
    index 'foo', PVBM;
    my $pvbm = PVBM;

    sub foo { exit 0 }

    $SIG{"INT"} = $pvbm;
    kill "INT", $$; sleep 1;
END
    close CMDPIPE;
    $? >>= 8 if $^O eq 'VMS';
    print $? ? "not ok $tn[5]\n" : "ok $tn[5]\n";

    curr_test(curr_test() + 5);
}

# can we slice ENV?
@val1 = @ENV{keys(%ENV)};
@val2 = values(%ENV);
is join(':',@val1), join(':',@val2);
cmp_ok @val1, '>', 1;

# regex vars
'foobarbaz' =~ /b(a)r/;
is $`, 'foo';
is $&, 'bar';
is $', 'baz';
is $+, 'a';

# $"
@a = qw(foo bar baz);
is "@a", "foo bar baz";
{
    local $" = ',';
    is "@a", "foo,bar,baz";
}

# $;
%h = ();
$h{'foo', 'bar'} = 1;
is((keys %h)[0], "foo\034bar");
{
    local $; = 'x';
    %h = ();
    $h{'foo', 'bar'} = 1;
    is((keys %h)[0], 'fooxbar');
}

# $?, $@, $$
system qq[$PERL "-I../lib" -e "use vmsish qw(hushed); exit(0)"];
is $?, 0;
system qq[$PERL "-I../lib" -e "use vmsish qw(hushed); exit(1)"];
isnt $?, 0;

eval { die "foo\n" };
is $@, "foo\n";

cmp_ok($$, '>', 0);
my $pid = $$;
eval { $$ = 42 };
is $$, 42, '$$ can be modified';
SKIP: {
    skip "no fork", 1 unless $Config{d_fork};
    (my $kidpid = open my $fh, "-|") // skip "cannot fork: $!", 1;
    if($kidpid) { # parent
	my $kiddollars = <$fh>;
	close $fh or die "cannot close pipe from kid proc: $!";
	is $kiddollars, $kidpid, '$$ is reset on fork';
    }
    else { # child
	print $$;
	$::NO_ENDING = 1; # silence "Looks like you only ran..."
	exit;
    }
}
$$ = $pid; # Tests below use $$

# $^X and $0
{
    my $is_abs = $Config{d_procselfexe} || $Config{usekernprocpathname}
      || $Config{usensgetexecutablepath};
    if ($^O eq 'qnx') {
	chomp($wd = `/usr/bin/fullpath -t`);
    }
    elsif($Is_Cygwin || $is_abs) {
       # Cygwin turns the symlink into the real file
       chomp($wd = `pwd`);
       $wd =~ s#/t$##;
       $wd =~ /(.*)/; $wd = $1; # untaint
       if ($Is_Cygwin) {
	   $wd = Cygwin::win_to_posix_path(Cygwin::posix_to_win_path($wd, 1));
       }
    }
    elsif($Is_os2) {
       $wd = Cwd::sys_cwd();
    }
    else {
	$wd = '.';
    }
    my $perl = $Is_VMS || $is_abs ? $^X : "$wd/perl";
    my $headmaybe = '';
    my $middlemaybe = '';
    my $tailmaybe = '';
    $script = "$wd/show-shebang";
    if ($Is_MSWin32) {
	chomp($wd = `cd`);
	$wd =~ s|\\|/|g;
	$perl = "$wd/perl.exe";
	$script = "$wd/show-shebang.bat";
	$headmaybe = <<EOH ;
\@rem ='
\@echo off
$perl -x \%0
goto endofperl
\@rem ';
EOH
	$tailmaybe = <<EOT ;

__END__
:endofperl
EOT
    }
    elsif ($Is_os2) {
      $script = "./show-shebang";
    }
    elsif ($Is_VMS) {
      $script = "[]show-shebang";
    }
    elsif ($Is_Cygwin) {
      $middlemaybe = <<'EOX'
$^X = Cygwin::win_to_posix_path(Cygwin::posix_to_win_path($^X, 1));
$0 = Cygwin::win_to_posix_path(Cygwin::posix_to_win_path($0, 1));
EOX
    }
    if ($^O eq 'os390' or $^O eq 'posix-bc' or $^O eq 'vmesa') {  # no shebang
	$headmaybe = <<EOH ;
    eval 'exec ./perl -S \$0 \${1+"\$\@"}'
        if 0;
EOH
    }
    $s1 = "\$^X is $perl, \$0 is $script\n";
    ok open(SCRIPT, ">$script") or diag "Can't write to $script: $!";
    ok print(SCRIPT $headmaybe . <<EOB . $middlemaybe . <<'EOF' . $tailmaybe) or diag $!;
#!$perl
EOB
print "\$^X is $^X, \$0 is $0\n";
EOF
    ok close(SCRIPT) or diag $!;
    ok chmod(0755, $script) or diag $!;
    $_ = $Is_VMS ? `$perl $script` : `$script`;
    s/\.exe//i if $Is_Dos or $Is_Cygwin or $Is_os2;
    s{./$script}{$script} if $Is_BeOS; # revert BeOS execvp() side-effect
    s{is perl}{is $perl}; # for systems where $^X is only a basename
    s{\\}{/}g;
    if ($Is_MSWin32 || $Is_os2) {
	is uc $_, uc $s1;
    } else {
	is $_, $s1;
    }
    $_ = `$perl $script`;
    s/\.exe//i if $Is_Dos or $Is_os2 or $Is_Cygwin;
    s{./$perl}{$perl} if $Is_BeOS; # revert BeOS execvp() side-effect
    s{\\}{/}g;
    if ($Is_MSWin32 || $Is_os2) {
	is uc $_, uc $s1;
    } else {
	is $_, $s1;
    }
    ok unlink($script) or diag $!;
    # CHECK
    # Could this be replaced with:
    # unlink_all($script);
}

# $], $^O, $^T
cmp_ok $], '>=', 5.00319;
ok $^O;
cmp_ok $^T, '>', 850000000;

# Test change 25062 is working
my $orig_osname = $^O;
{
local $^I = '.bak';
is $^O, $orig_osname, 'Assigning $^I does not clobber $^O';
}
$^O = $orig_osname;

{
    #RT #72422
    foreach my $p (0, 1) {
	fresh_perl_is(<<"EOP", '2 4 8', undef, "test \$^P = $p");
\$DB::single = 2;
\$DB::trace = 4;
\$DB::signal = 8;
\$^P = $p;
print "\$DB::single \$DB::trace \$DB::signal";
EOP
    }
}

# Check that assigning to $0 on Linux sets the process name with both
# argv[0] assignment and by calling prctl()
{
  SKIP: {
    skip "We don't have prctl() here", 2 unless $Config{d_prctl_set_name};

    # We don't really need these tests. prctl() is tested in the
    # Kernel, but test it anyway for our sanity. If something doesn't
    # work (like if the system doesn't have a ps(1) for whatever
    # reason) just bail out gracefully.
    my $maybe_ps = sub {
        my ($cmd) = @_;
        local ($?, $!);

        no warnings;
        my $res = `$cmd`;
        skip "Couldn't shell out to '$cmd', returned code $?", 2 if $?;
        return $res;
    };

    my $name = "Good Morning, Dave";
    $0 = $name;

    chomp(my $argv0 = $maybe_ps->("ps h $$"));
    chomp(my $prctl = $maybe_ps->("ps hc $$"));

    like($argv0, $name, "Set process name through argv[0] ($argv0)");
    like($prctl, substr($name, 0, 15), "Set process name through prctl() ($prctl)");
  }
}

{
    my $ok = 1;
    my $warn = '';
    local $SIG{'__WARN__'} = sub { $ok = 0; $warn = join '', @_; $warn =~ s/\n$//; };
    $! = undef;
    local $TODO = $Is_VMS ? "'\$!=undef' does throw a warning" : '';
    ok($ok, $warn);
}

SKIP: {
    skip_if_miniperl("miniperl can't rely on loading %Errno", 2);
   no warnings 'void';

# Make sure Errno hasn't been prematurely autoloaded

   ok !keys %Errno::;

# Test auto-loading of Errno when %! is used

   ok scalar eval q{
      %!;
      scalar %Errno::;
   }, $@;
}

SKIP:  {
    skip_if_miniperl("miniperl can't rely on loading %Errno", 1);
    # Make sure that Errno loading doesn't clobber $!

    undef %Errno::;
    delete $INC{"Errno.pm"};

    open(FOO, "nonesuch"); # Generate ENOENT
    my %errs = %{"!"}; # Cause Errno.pm to be loaded at run-time
    ok ${"!"}{ENOENT};
}

# Check that we don't auto-load packages
SKIP: {
    skip "staticly linked; may be preloaded", 4 unless $Config{usedl};
    foreach (['powie::!', 'Errno'],
	     ['powie::+', 'Tie::Hash::NamedCapture']) {
	my ($symbol, $package) = @$_;
	foreach my $scalar_first ('', '$$symbol;') {
	    my $desc = qq{Referencing %{"$symbol"}};
	    $desc .= qq{ after mentioning \${"$symbol"}} if $scalar_first;
	    $desc .= " doesn't load $package";

	    fresh_perl_is(<<"EOP", 0, {}, $desc);
use strict qw(vars subs);
my \$symbol = '$symbol';
$scalar_first;
1 if %{\$symbol};
print scalar %${package}::;
EOP
	}
    }
}

is $^S, 0;
eval { is $^S,1 };
eval " BEGIN { ok ! defined \$^S } ";
is $^S, 0;

my $taint = ${^TAINT};
is ${^TAINT}, $taint;
eval { ${^TAINT} = 1 };
is ${^TAINT}, $taint;

# 5.6.1 had a bug: @+ and @- were not properly interpolated
# into double-quoted strings
# 20020414 mjd-perl-patch+@plover.com
"I like pie" =~ /(I) (like) (pie)/;
is "@-",  "0 0 2 7";
is "@+", "10 1 6 10";

# Tests for the magic get of $\
{
    my $ok = 0;
    # [perl #19330]
    {
	local $\ = undef;
	$\++; $\++;
	$ok = $\ eq 2;
    }
    ok $ok;
    $ok = 0;
    {
	local $\ = "a\0b";
	$ok = "a$\b" eq "aa\0bb";
    }
    ok $ok;
}

# Test for bug [perl #36434]
# Can not do this test on VMS, EPOC, and SYMBIAN according to comments
# in mg.c/Perl_magic_clear_all_env()
SKIP: {
    skip('Can\'t make assignment to \%ENV on this system', 3) if $Is_VMS;

    local @ISA;
    local %ENV;
    # This used to be __PACKAGE__, but that causes recursive
    #  inheritance, which is detected earlier now and broke
    #  this test
    eval { push @ISA, __FILE__ };
    is $@, '', 'Push a constant on a magic array';
    $@ and print "# $@";
    eval { %ENV = (PATH => __PACKAGE__) };
    is $@, '', 'Assign a constant to a magic hash';
    $@ and print "# $@";
    eval { my %h = qw(A B); %ENV = (PATH => (keys %h)[0]) };
    is $@, '', 'Assign a shared key to a magic hash';
    $@ and print "# $@";
}

# Tests for Perl_magic_clearsig
foreach my $sig (qw(__WARN__ INT)) {
    $SIG{$sig} = lc $sig;
    is $SIG{$sig}, 'main::' . lc $sig, "Can assign to $sig";
    is delete $SIG{$sig}, 'main::' . lc $sig, "Can delete from $sig";
    is $SIG{$sig}, undef, "$sig is now gone";
    is delete $SIG{$sig}, undef, "$sig remains gone";
}

# And now one which doesn't exist;
{
    no warnings 'signal';
    $SIG{HUNGRY} = 'mmm, pie';
}
is $SIG{HUNGRY}, 'mmm, pie', 'Can assign to HUNGRY';
is delete $SIG{HUNGRY}, 'mmm, pie', 'Can delete from HUNGRY';
is $SIG{HUNGRY}, undef, "HUNGRY is now gone";
is delete $SIG{HUNGRY}, undef, "HUNGRY remains gone";

# Test deleting signals that we never set
foreach my $sig (qw(__DIE__ _BOGUS_HOOK KILL THIRSTY)) {
    is $SIG{$sig}, undef, "$sig is not present";
    is delete $SIG{$sig}, undef, "delete of $sig returns undef";
}

{
    $! = 9999;
    is int $!, 9999, q{[perl #72850] Core dump in bleadperl from perl -e '$! = 9999; $a = $!;'};

}

SKIP: {
    skip_if_miniperl("No XS in miniperl", 3);

    for ( [qw( %- Tie::Hash::NamedCapture )], [qw( $[ arybase )],
          [qw( %! Errno )] ) {
	my ($var, $mod) = @$_;
	my $modfile = $mod =~ s|::|/|gr . ".pm";
	fresh_perl_is
	   qq 'sub UNIVERSAL::AUTOLOAD{}
	       $mod\::foo() if 0;
	       $var;
	       print "ok\\n" if \$INC{"$modfile"}',
	  "ok\n",
	   { switches => [ '-X' ] },
	  "$var still loads $mod when stash and UNIVERSAL::AUTOLOAD exist";
    }
}

# ^^^^^^^^^ New tests go here ^^^^^^^^^

SKIP: {
    skip("%ENV manipulations fail or aren't safe on $^O", 4)
	if $Is_VMS || $Is_Dos;

 SKIP: {
	skip("clearing \%ENV is not safe when running under valgrind")
	    if $ENV{PERL_VALGRIND};

	    $PATH = $ENV{PATH};
	    $PDL = $ENV{PERL_DESTRUCT_LEVEL} || 0;
	    $ENV{foo} = "bar";
	    %ENV = ();
	    $ENV{PATH} = $PATH;
	    $ENV{PERL_DESTRUCT_LEVEL} = $PDL || 0;
	    if ($Is_MSWin32) {
		is `set foo 2>NUL`, "";
	    } else {
		is `echo \$foo`, "\n";
	    }
	}

	$ENV{__NoNeSuCh} = "foo";
	$0 = "bar";
# cmd.exe will echo 'variable=value' but 4nt will echo just the value
# -- Nikola Knezevic
    	if ($Is_MSWin32) {
	    like `set __NoNeSuCh`, qr/^(?:__NoNeSuCh=)?foo$/;
	} else {
	    is `echo \$__NoNeSuCh`, "foo\n";
	}
    SKIP: {
	    skip("\$0 check only on Linux and FreeBSD", 2)
		unless $^O =~ /^(linux|freebsd)$/
		    && open CMDLINE, "/proc/$$/cmdline";

	    chomp(my $line = scalar <CMDLINE>);
	    my $me = (split /\0/, $line)[0];
	    is $me, $0, 'altering $0 is effective (testing with /proc/)';
	    close CMDLINE;
            # perlbug #22811
            my $mydollarzero = sub {
              my($arg) = shift;
              $0 = $arg if defined $arg;
	      # In FreeBSD the ps -o command= will cause
	      # an empty header line, grab only the last line.
              my $ps = (`ps -o command= -p $$`)[-1];
              return if $?;
              chomp $ps;
              printf "# 0[%s]ps[%s]\n", $0, $ps;
              $ps;
            };
            my $ps = $mydollarzero->("x");
            ok(!$ps  # we allow that something goes wrong with the ps command
	       # In Linux 2.4 we would get an exact match ($ps eq 'x') but
	       # in Linux 2.2 there seems to be something funny going on:
	       # it seems as if the original length of the argv[] would
	       # be stored in the proc struct and then used by ps(1),
	       # no matter what characters we use to pad the argv[].
	       # (And if we use \0:s, they are shown as spaces.)  Sigh.
               || $ps =~ /^x\s*$/
	       # FreeBSD cannot get rid of both the leading "perl :"
	       # and the trailing " (perl)": some FreeBSD versions
	       # can get rid of the first one.
	       || ($^O eq 'freebsd' && $ps =~ m/^(?:perl: )?x(?: \(perl\))?$/),
		       'altering $0 is effective (testing with `ps`)');
	}
}

# test case-insignificance of %ENV (these tests must be enabled only
# when perl is compiled with -DENV_IS_CASELESS)
SKIP: {
    skip('no caseless %ENV support', 4) unless $Is_MSWin32 || $Is_NetWare;

    %ENV = ();
    $ENV{'Foo'} = 'bar';
    $ENV{'fOo'} = 'baz';
    is scalar(keys(%ENV)), 1;
    ok exists $ENV{'FOo'};
    is delete $ENV{'foO'}, 'baz';
    is scalar(keys(%ENV)), 0;
}

__END__

# Put new tests before the various ENV tests, as they blow %ENV away.