xref: /openbsd/gnu/usr.bin/perl/t/op/goto.t (revision 8529ddd3)
1#!./perl
2
3# "This IS structured code.  It's just randomly structured."
4
5BEGIN {
6    chdir 't' if -d 't';
7    @INC = qw(. ../lib);
8    require "test.pl";
9}
10
11use warnings;
12use strict;
13plan tests => 94;
14our $TODO;
15
16my $deprecated = 0;
17local $SIG{__WARN__} = sub { if ($_[0] =~ m/jump into a construct/) { $deprecated++; } else { warn $_[0] } };
18
19our $foo;
20while ($?) {
21    $foo = 1;
22  label1:
23    is($deprecated, 1, "following label1");
24    $deprecated = 0;
25    $foo = 2;
26    goto label2;
27} continue {
28    $foo = 0;
29    goto label4;
30  label3:
31    is($deprecated, 1, "following label3");
32    $deprecated = 0;
33    $foo = 4;
34    goto label4;
35}
36is($deprecated, 0, "after 'while' loop");
37goto label1;
38
39$foo = 3;
40
41label2:
42is($foo, 2, 'escape while loop');
43is($deprecated, 0, "following label2");
44goto label3;
45
46label4:
47is($foo, 4, 'second escape while loop');
48
49my $r = run_perl(prog => 'goto foo;', stderr => 1);
50like($r, qr/label/, 'cant find label');
51
52my $ok = 0;
53sub foo {
54    goto bar;
55    return;
56bar:
57    $ok = 1;
58}
59
60&foo;
61ok($ok, 'goto in sub');
62
63sub bar {
64    my $x = 'bypass';
65    eval "goto $x";
66}
67
68&bar;
69exit;
70
71FINALE:
72is(curr_test(), 20, 'FINALE');
73
74# does goto LABEL handle block contexts correctly?
75# note that this scope-hopping differs from last & next,
76# which always go up-scope strictly.
77my $count = 0;
78my $cond = 1;
79for (1) {
80    if ($cond == 1) {
81	$cond = 0;
82	goto OTHER;
83    }
84    elsif ($cond == 0) {
85      OTHER:
86	$cond = 2;
87	is($count, 0, 'OTHER');
88	$count++;
89	goto THIRD;
90    }
91    else {
92      THIRD:
93	is($count, 1, 'THIRD');
94	$count++;
95    }
96}
97is($count, 2, 'end of loop');
98
99# Does goto work correctly within a for(;;) loop?
100#  (BUG ID 20010309.004)
101
102for(my $i=0;!$i++;) {
103  my $x=1;
104  goto label;
105  label: is($x, 1, 'goto inside a for(;;) loop body from inside the body');
106}
107
108# Does goto work correctly going *to* a for(;;) loop?
109#  (make sure it doesn't skip the initializer)
110
111my ($z, $y) = (0);
112FORL1: for ($y=1; $z;) {
113    ok($y, 'goto a for(;;) loop, from outside (does initializer)');
114    goto TEST19}
115($y,$z) = (0, 1);
116goto FORL1;
117
118# Even from within the loop?
119TEST19: $z = 0;
120FORL2: for($y=1; 1;) {
121  if ($z) {
122    ok($y, 'goto a for(;;) loop, from inside (does initializer)');
123    last;
124  }
125  ($y, $z) = (0, 1);
126  goto FORL2;
127}
128
129# Does goto work correctly within a try block?
130#  (BUG ID 20000313.004) - [perl #2359]
131$ok = 0;
132eval {
133  my $variable = 1;
134  goto LABEL20;
135  LABEL20: $ok = 1 if $variable;
136};
137ok($ok, 'works correctly within a try block');
138is($@, "", '...and $@ not set');
139
140# And within an eval-string?
141$ok = 0;
142eval q{
143  my $variable = 1;
144  goto LABEL21;
145  LABEL21: $ok = 1 if $variable;
146};
147ok($ok, 'works correctly within an eval string');
148is($@, "", '...and $@ still not set');
149
150
151# Test that goto works in nested eval-string
152$ok = 0;
153{eval q{
154  eval q{
155    goto LABEL22;
156  };
157  $ok = 0;
158  last;
159
160  LABEL22: $ok = 1;
161};
162$ok = 0 if $@;
163}
164ok($ok, 'works correctly in a nested eval string');
165
166{
167    my $false = 0;
168    my $count;
169
170    $ok = 0;
171    { goto A; A: $ok = 1 } continue { }
172    ok($ok, '#20357 goto inside /{ } continue { }/ loop');
173
174    $ok = 0;
175    { do { goto A; A: $ok = 1 } while $false }
176    ok($ok, '#20154 goto inside /do { } while ()/ loop');
177    $ok = 0;
178    foreach(1) { goto A; A: $ok = 1 } continue { };
179    ok($ok, 'goto inside /foreach () { } continue { }/ loop');
180
181    $ok = 0;
182    sub a {
183	A: { if ($false) { redo A; B: $ok = 1; redo A; } }
184	goto B unless $count++;
185    }
186    is($deprecated, 0, "before calling sub a()");
187    a();
188    ok($ok, '#19061 loop label wiped away by goto');
189    is($deprecated, 1, "after calling sub a()");
190    $deprecated = 0;
191
192    $ok = 0;
193    my $p;
194    for ($p=1;$p && goto A;$p=0) { A: $ok = 1 }
195    ok($ok, 'weird case of goto and for(;;) loop');
196    is($deprecated, 1, "following goto and for(;;) loop");
197    $deprecated = 0;
198}
199
200# bug #9990 - don't prematurely free the CV we're &going to.
201
202sub f1 {
203    my $x;
204    goto sub { $x=0; ok(1,"don't prematurely free CV\n") }
205}
206f1();
207
208# bug #99850, which is similar - freeing the subroutine we are about to
209# go(in)to during a FREETMPS call should not crash perl.
210
211package _99850 {
212    sub reftype{}
213    DESTROY { undef &reftype }
214    eval { sub { my $guard = bless []; goto &reftype }->() };
215}
216like $@, qr/^Goto undefined subroutine &_99850::reftype at /,
217   'goto &foo undefining &foo on sub cleanup';
218
219# bug #22181 - this used to coredump or make $x undefined, due to
220# erroneous popping of the inner BLOCK context
221
222undef $ok;
223for ($count=0; $count<2; $count++) {
224    my $x = 1;
225    goto LABEL29;
226    LABEL29:
227    $ok = $x;
228}
229is($ok, 1, 'goto in for(;;) with continuation');
230
231# bug #22299 - goto in require doesn't find label
232
233open my $f, ">Op_goto01.pm" or die;
234print $f <<'EOT';
235package goto01;
236goto YYY;
237die;
238YYY: print "OK\n";
2391;
240EOT
241close $f;
242
243$r = runperl(prog => 'use Op_goto01; print qq[DONE\n]');
244is($r, "OK\nDONE\n", "goto within use-d file");
245unlink_all "Op_goto01.pm";
246
247# test for [perl #24108]
248$ok = 1;
249$count = 0;
250sub i_return_a_label {
251    $count++;
252    return "returned_label";
253}
254eval { goto +i_return_a_label; };
255$ok = 0;
256
257returned_label:
258is($count, 1, 'called i_return_a_label');
259ok($ok, 'skipped to returned_label');
260
261# [perl #29708] - goto &foo could leave foo() at depth two with
262# @_ == PL_sv_undef, causing a coredump
263
264
265$r = runperl(
266    prog =>
267	'sub f { return if $d; $d=1; my $a=sub {goto &f}; &$a; f() } f(); print qq(ok\n)',
268    stderr => 1
269    );
270is($r, "ok\n", 'avoid pad without an @_');
271
272goto moretests;
273fail('goto moretests');
274exit;
275
276bypass:
277
278is(curr_test(), 9, 'eval "goto $x"');
279
280# Test autoloading mechanism.
281
282sub two {
283    my ($pack, $file, $line) = caller;	# Should indicate original call stats.
284    is("@_ $pack $file $line", "1 2 3 main $::FILE $::LINE",
285	'autoloading mechanism.');
286}
287
288sub one {
289    eval <<'END';
290    no warnings 'redefine';
291    sub one { pass('sub one'); goto &two; fail('sub one tail'); }
292END
293    goto &one;
294}
295
296$::FILE = __FILE__;
297$::LINE = __LINE__ + 1;
298&one(1,2,3);
299
300{
301    my $wherever = 'NOWHERE';
302    eval { goto $wherever };
303    like($@, qr/Can't find label NOWHERE/, 'goto NOWHERE sets $@');
304}
305
306# see if a modified @_ propagates
307{
308  my $i;
309  package Foo;
310  sub DESTROY	{ my $s = shift; ::is($s->[0], $i, "destroy $i"); }
311  sub show	{ ::is(+@_, 5, "show $i",); }
312  sub start	{ push @_, 1, "foo", {}; goto &show; }
313  for (1..3)	{ $i = $_; start(bless([$_]), 'bar'); }
314}
315
316sub auto {
317    goto &loadit;
318}
319
320sub AUTOLOAD { $ok = 1 if "@_" eq "foo" }
321
322$ok = 0;
323auto("foo");
324ok($ok, 'autoload');
325
326{
327    my $wherever = 'FINALE';
328    goto $wherever;
329}
330fail('goto $wherever');
331
332moretests:
333# test goto duplicated labels.
334{
335    my $z = 0;
336    eval {
337	$z = 0;
338	for (0..1) {
339	  L4: # not outer scope
340	    $z += 10;
341	    last;
342	}
343	goto L4 if $z == 10;
344	last;
345    };
346    like($@, qr/Can't "goto" into the middle of a foreach loop/,
347	    'catch goto middle of foreach');
348
349    $z = 0;
350    # ambiguous label resolution (outer scope means endless loop!)
351  L1:
352    for my $x (0..1) {
353	$z += 10;
354	is($z, 10, 'prefer same scope (loop body) to outer scope (loop entry)');
355	goto L1 unless $x;
356	$z += 10;
357      L1:
358	is($z, 10, 'prefer same scope: second');
359	last;
360    }
361
362    $z = 0;
363  L2:
364    {
365	$z += 10;
366	is($z, 10, 'prefer this scope (block body) to outer scope (block entry)');
367	goto L2 if $z == 10;
368	$z += 10;
369      L2:
370	is($z, 10, 'prefer this scope: second');
371    }
372
373
374    {
375	$z = 0;
376	while (1) {
377	  L3: # not inner scope
378	    $z += 10;
379	    last;
380	}
381	is($z, 10, 'prefer this scope to inner scope');
382	goto L3 if $z == 10;
383	$z += 10;
384      L3: # this scope !
385	is($z, 10, 'prefer this scope to inner scope: second');
386    }
387
388  L4: # not outer scope
389    {
390	$z = 0;
391	while (1) {
392	  L4: # not inner scope
393	    $z += 1;
394	    last;
395	}
396	is($z, 1, 'prefer this scope to inner,outer scopes');
397	goto L4 if $z == 1;
398	$z += 10;
399      L4: # this scope !
400	is($z, 1, 'prefer this scope to inner,outer scopes: second');
401    }
402
403    {
404	my $loop = 0;
405	for my $x (0..1) {
406	  L2: # without this, fails 1 (middle) out of 3 iterations
407	    $z = 0;
408	  L2:
409	    $z += 10;
410	    is($z, 10,
411		"same label, multiple times in same scope (choose 1st) $loop");
412	    goto L2 if $z == 10 and not $loop++;
413	}
414    }
415}
416
417# deep recursion with gotos eventually caused a stack reallocation
418# which messed up buggy internals that didn't expect the stack to move
419
420sub recurse1 {
421    unshift @_, "x";
422    no warnings 'recursion';
423    goto &recurse2;
424}
425sub recurse2 {
426    my $x = shift;
427    $_[0] ? +1 + recurse1($_[0] - 1) : 0
428}
429my $w = 0;
430$SIG{__WARN__} = sub { ++$w };
431is(recurse1(500), 500, 'recursive goto &foo');
432is $w, 0, 'no recursion warnings for "no warnings; goto &sub"';
433delete $SIG{__WARN__};
434
435# [perl #32039] Chained goto &sub drops data too early.
436
437sub a32039 { @_=("foo"); goto &b32039; }
438sub b32039 { goto &c32039; }
439sub c32039 { is($_[0], 'foo', 'chained &goto') }
440a32039();
441
442# [perl #35214] next and redo re-entered the loop with the wrong cop,
443# causing a subsequent goto to crash
444
445{
446    my $r = runperl(
447		stderr => 1,
448		prog =>
449'for ($_=0;$_<3;$_++){A: if($_==1){next} if($_==2){$_++;goto A}}print qq(ok\n)'
450    );
451    is($r, "ok\n", 'next and goto');
452
453    $r = runperl(
454		stderr => 1,
455		prog =>
456'for ($_=0;$_<3;$_++){A: if($_==1){$_++;redo} if($_==2){$_++;goto A}}print qq(ok\n)'
457    );
458    is($r, "ok\n", 'redo and goto');
459}
460
461# goto &foo not allowed in evals
462
463sub null { 1 };
464eval 'goto &null';
465like($@, qr/Can't goto subroutine from an eval-string/, 'eval string');
466eval { goto &null };
467like($@, qr/Can't goto subroutine from an eval-block/, 'eval block');
468
469# goto &foo leaves @_ alone when called from a sub
470sub returnarg { $_[0] };
471is sub {
472    local *_ = ["ick and queasy"];
473    goto &returnarg;
474}->("quick and easy"), "ick and queasy",
475  'goto &foo with *_{ARRAY} replaced';
476my @__ = "\xc4\x80";
477sub { local *_ = \@__; goto &utf8::decode }->("no thinking aloud");
478is "@__", chr 256, 'goto &xsub with replaced *_{ARRAY}';
479
480# And goto &foo should leave reified @_ alone
481sub { *__ = \@_;  goto &null } -> ("rough and tubbery");
482is ${*__}[0], 'rough and tubbery', 'goto &foo leaves reified @_ alone';
483
484# goto &xsub when @_ has nonexistent elements
485{
486    no warnings "uninitialized";
487    local @_ = ();
488    $#_++;
489    & {sub { goto &utf8::encode }};
490    is @_, 1, 'num of elems in @_ after goto &xsub with nonexistent $_[0]';
491    is $_[0], "", 'content of nonexistent $_[0] is modified by goto &xsub';
492}
493
494# goto &xsub when @_ itself does not exist
495undef *_;
496eval { & { sub { goto &utf8::encode } } };
497# The main thing we are testing is that it did not crash.  But make sure
498# *_{ARRAY} was untouched, too.
499is *_{ARRAY}, undef, 'goto &xsub when @_ does not exist';
500
501# goto &perlsub when @_ itself does not exist [perl #119949]
502# This was only crashing when the replaced sub call had an argument list.
503# (I.e., &{ sub { goto ... } } did not crash.)
504sub {
505    undef *_;
506    goto sub {
507	is *_{ARRAY}, undef, 'goto &perlsub when @_ does not exist';
508    }
509}->();
510sub {
511    local *_;
512    goto sub {
513	is *_{ARRAY}, undef, 'goto &sub when @_ does not exist (local *_)';
514    }
515}->();
516
517
518# [perl #36521] goto &foo in warn handler could defeat recursion avoider
519
520{
521    my $r = runperl(
522		stderr => 1,
523		prog => 'my $d; my $w = sub { return if $d++; warn q(bar)}; local $SIG{__WARN__} = sub { goto &$w; }; warn q(foo);'
524    );
525    like($r, qr/bar/, "goto &foo in warn");
526}
527
528TODO: {
529    local $TODO = "[perl #43403] goto() from an if to an else doesn't undo local () changes";
530    our $global = "unmodified";
531    if ($global) { # true but not constant-folded
532         local $global = "modified";
533         goto ELSE;
534    } else {
535         ELSE: is($global, "unmodified");
536    }
537}
538
539is($deprecated, 0, "following TODOed test for #43403");
540
541#74290
542{
543    my $x;
544    my $y;
545    F1:++$x and eval 'return if ++$y == 10; goto F1;';
546    is($x, 10,
547       'labels outside evals can be distinguished from the start of the eval');
548}
549
550goto wham_eth;
551die "You can't get here";
552
553wham_eth: 1 if 0;
554ouch_eth: pass('labels persist even if their statement is optimised away');
555
556$foo = "(0)";
557if($foo eq $foo) {
558    goto bungo;
559}
560$foo .= "(9)";
561bungo:
562format CHOLET =
563wellington
564.
565$foo .= "(1)";
566SKIP: {
567    skip_if_miniperl("no dynamic loading on miniperl, so can't load PerlIO::scalar", 1);
568    my $cholet;
569    open(CHOLET, ">", \$cholet);
570    write CHOLET;
571    close CHOLET;
572    $foo .= "(".$cholet.")";
573    is($foo, "(0)(1)(wellington\n)", "label before format decl");
574}
575
576$foo = "(A)";
577if($foo eq $foo) {
578    goto orinoco;
579}
580$foo .= "(X)";
581orinoco:
582sub alderney { return "tobermory"; }
583$foo .= "(B)";
584$foo .= "(".alderney().")";
585is($foo, "(A)(B)(tobermory)", "label before sub decl");
586
587$foo = "[0:".__PACKAGE__."]";
588if($foo eq $foo) {
589    goto bulgaria;
590}
591$foo .= "[9]";
592bulgaria:
593package Tomsk;
594$foo .= "[1:".__PACKAGE__."]";
595$foo .= "[2:".__PACKAGE__."]";
596package main;
597$foo .= "[3:".__PACKAGE__."]";
598is($foo, "[0:main][1:Tomsk][2:Tomsk][3:main]", "label before package decl");
599
600$foo = "[A:".__PACKAGE__."]";
601if($foo eq $foo) {
602    goto adelaide;
603}
604$foo .= "[Z]";
605adelaide:
606package Cairngorm {
607    $foo .= "[B:".__PACKAGE__."]";
608}
609$foo .= "[C:".__PACKAGE__."]";
610is($foo, "[A:main][B:Cairngorm][C:main]", "label before package block");
611
612our $obidos;
613$foo = "{0}";
614if($foo eq $foo) {
615    goto shansi;
616}
617$foo .= "{9}";
618shansi:
619BEGIN { $obidos = "x"; }
620$foo .= "{1$obidos}";
621is($foo, "{0}{1x}", "label before BEGIN block");
622
623$foo = "{A:".(1.5+1.5)."}";
624if($foo eq $foo) {
625    goto stepney;
626}
627$foo .= "{Z}";
628stepney:
629use integer;
630$foo .= "{B:".(1.5+1.5)."}";
631is($foo, "{A:3}{B:2}", "label before use decl");
632
633$foo = "<0>";
634if($foo eq $foo) {
635    goto tom;
636}
637$foo .= "<9>";
638tom: dick: harry:
639$foo .= "<1>";
640$foo .= "<2>";
641is($foo, "<0><1><2>", "first of three stacked labels");
642
643$foo = "<A>";
644if($foo eq $foo) {
645    goto beta;
646}
647$foo .= "<Z>";
648alpha: beta: gamma:
649$foo .= "<B>";
650$foo .= "<C>";
651is($foo, "<A><B><C>", "second of three stacked labels");
652
653$foo = ",0.";
654if($foo eq $foo) {
655    goto gimel;
656}
657$foo .= ",9.";
658alef: bet: gimel:
659$foo .= ",1.";
660$foo .= ",2.";
661is($foo, ",0.,1.,2.", "third of three stacked labels");
662
663# [perl #112316] Wrong behavior regarding labels with same prefix
664sub same_prefix_labels {
665    my $pass;
666    my $first_time = 1;
667    CATCH: {
668        if ( $first_time ) {
669            CATCHLOOP: {
670                if ( !$first_time ) {
671                  return 0;
672                }
673                $first_time--;
674                goto CATCH;
675            }
676        }
677        else {
678            return 1;
679        }
680    }
681}
682
683ok(
684   same_prefix_labels(),
685   "perl 112316: goto and labels with the same prefix doesn't get mixed up"
686);
687
688eval { my $x = ""; goto $x };
689like $@, qr/^goto must have label at /, 'goto $x where $x is empty string';
690eval { goto "" };
691like $@, qr/^goto must have label at /, 'goto ""';
692eval { goto };
693like $@, qr/^goto must have label at /, 'argless goto';
694
695eval { my $x = "\0"; goto $x };
696like $@, qr/^Can't find label \0 at /, 'goto $x where $x begins with \0';
697eval { goto "\0" };
698like $@, qr/^Can't find label \0 at /, 'goto "\0"';
699
700sub TIESCALAR { bless [pop] }
701sub FETCH     { $_[0][0] }
702tie my $t, "", sub { "cluck up porridge" };
703is eval { sub { goto $t }->() }//$@, 'cluck up porridge',
704  'tied arg returning sub ref';
705