xref: /openbsd-src/gnu/usr.bin/perl/t/op/goto.t (revision a28daedfc357b214be5c701aa8ba8adb29a7f1c2)
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 => 58;
14our $TODO;
15
16our $foo;
17while ($?) {
18    $foo = 1;
19  label1:
20    $foo = 2;
21    goto label2;
22} continue {
23    $foo = 0;
24    goto label4;
25  label3:
26    $foo = 4;
27    goto label4;
28}
29goto label1;
30
31$foo = 3;
32
33label2:
34is($foo, 2, 'escape while loop');
35goto label3;
36
37label4:
38is($foo, 4, 'second escape while loop');
39
40my $r = run_perl(prog => 'goto foo;', stderr => 1);
41like($r, qr/label/, 'cant find label');
42
43my $ok = 0;
44sub foo {
45    goto bar;
46    return;
47bar:
48    $ok = 1;
49}
50
51&foo;
52ok($ok, 'goto in sub');
53
54sub bar {
55    my $x = 'bypass';
56    eval "goto $x";
57}
58
59&bar;
60exit;
61
62FINALE:
63is(curr_test(), 16, 'FINALE');
64
65# does goto LABEL handle block contexts correctly?
66# note that this scope-hopping differs from last & next,
67# which always go up-scope strictly.
68my $count = 0;
69my $cond = 1;
70for (1) {
71    if ($cond == 1) {
72	$cond = 0;
73	goto OTHER;
74    }
75    elsif ($cond == 0) {
76      OTHER:
77	$cond = 2;
78	is($count, 0, 'OTHER');
79	$count++;
80	goto THIRD;
81    }
82    else {
83      THIRD:
84	is($count, 1, 'THIRD');
85	$count++;
86    }
87}
88is($count, 2, 'end of loop');
89
90# Does goto work correctly within a for(;;) loop?
91#  (BUG ID 20010309.004)
92
93for(my $i=0;!$i++;) {
94  my $x=1;
95  goto label;
96  label: is($x, 1, 'goto inside a for(;;) loop body from inside the body');
97}
98
99# Does goto work correctly going *to* a for(;;) loop?
100#  (make sure it doesn't skip the initializer)
101
102my ($z, $y) = (0);
103FORL1: for ($y=1; $z;) {
104    ok($y, 'goto a for(;;) loop, from outside (does initializer)');
105    goto TEST19}
106($y,$z) = (0, 1);
107goto FORL1;
108
109# Even from within the loop?
110TEST19: $z = 0;
111FORL2: for($y=1; 1;) {
112  if ($z) {
113    ok($y, 'goto a for(;;) loop, from inside (does initializer)');
114    last;
115  }
116  ($y, $z) = (0, 1);
117  goto FORL2;
118}
119
120# Does goto work correctly within a try block?
121#  (BUG ID 20000313.004) - [perl #2359]
122$ok = 0;
123eval {
124  my $variable = 1;
125  goto LABEL20;
126  LABEL20: $ok = 1 if $variable;
127};
128ok($ok, 'works correctly within a try block');
129is($@, "", '...and $@ not set');
130
131# And within an eval-string?
132$ok = 0;
133eval q{
134  my $variable = 1;
135  goto LABEL21;
136  LABEL21: $ok = 1 if $variable;
137};
138ok($ok, 'works correctly within an eval string');
139is($@, "", '...and $@ still not set');
140
141
142# Test that goto works in nested eval-string
143$ok = 0;
144{eval q{
145  eval q{
146    goto LABEL22;
147  };
148  $ok = 0;
149  last;
150
151  LABEL22: $ok = 1;
152};
153$ok = 0 if $@;
154}
155ok($ok, 'works correctly in a nested eval string');
156
157{
158    my $false = 0;
159    my $count;
160
161    $ok = 0;
162    { goto A; A: $ok = 1 } continue { }
163    ok($ok, '#20357 goto inside /{ } continue { }/ loop');
164
165    $ok = 0;
166    { do { goto A; A: $ok = 1 } while $false }
167    ok($ok, '#20154 goto inside /do { } while ()/ loop');
168    $ok = 0;
169    foreach(1) { goto A; A: $ok = 1 } continue { };
170    ok($ok, 'goto inside /foreach () { } continue { }/ loop');
171
172    $ok = 0;
173    sub a {
174	A: { if ($false) { redo A; B: $ok = 1; redo A; } }
175	goto B unless $count++;
176    }
177    a();
178    ok($ok, '#19061 loop label wiped away by goto');
179
180    $ok = 0;
181    my $p;
182    for ($p=1;$p && goto A;$p=0) { A: $ok = 1 }
183    ok($ok, 'weird case of goto and for(;;) loop');
184}
185
186# bug #9990 - don't prematurely free the CV we're &going to.
187
188sub f1 {
189    my $x;
190    goto sub { $x=0; ok(1,"don't prematurely free CV\n") }
191}
192f1();
193
194# bug #22181 - this used to coredump or make $x undefined, due to
195# erroneous popping of the inner BLOCK context
196
197undef $ok;
198for ($count=0; $count<2; $count++) {
199    my $x = 1;
200    goto LABEL29;
201    LABEL29:
202    $ok = $x;
203}
204is($ok, 1, 'goto in for(;;) with continuation');
205
206# bug #22299 - goto in require doesn't find label
207
208open my $f, ">goto01.pm" or die;
209print $f <<'EOT';
210package goto01;
211goto YYY;
212die;
213YYY: print "OK\n";
2141;
215EOT
216close $f;
217
218$r = runperl(prog => 'use goto01; print qq[DONE\n]');
219is($r, "OK\nDONE\n", "goto within use-d file");
220unlink "goto01.pm";
221
222# test for [perl #24108]
223$ok = 1;
224$count = 0;
225sub i_return_a_label {
226    $count++;
227    return "returned_label";
228}
229eval { goto +i_return_a_label; };
230$ok = 0;
231
232returned_label:
233is($count, 1, 'called i_return_a_label');
234ok($ok, 'skipped to returned_label');
235
236# [perl #29708] - goto &foo could leave foo() at depth two with
237# @_ == PL_sv_undef, causing a coredump
238
239
240$r = runperl(
241    prog =>
242	'sub f { return if $d; $d=1; my $a=sub {goto &f}; &$a; f() } f(); print qq(ok\n)',
243    stderr => 1
244    );
245is($r, "ok\n", 'avoid pad without an @_');
246
247goto moretests;
248fail('goto moretests');
249exit;
250
251bypass:
252
253is(curr_test(), 5, 'eval "goto $x"');
254
255# Test autoloading mechanism.
256
257sub two {
258    my ($pack, $file, $line) = caller;	# Should indicate original call stats.
259    is("@_ $pack $file $line", "1 2 3 main $::FILE $::LINE",
260	'autoloading mechanism.');
261}
262
263sub one {
264    eval <<'END';
265    no warnings 'redefine';
266    sub one { pass('sub one'); goto &two; fail('sub one tail'); }
267END
268    goto &one;
269}
270
271$::FILE = __FILE__;
272$::LINE = __LINE__ + 1;
273&one(1,2,3);
274
275{
276    my $wherever = 'NOWHERE';
277    eval { goto $wherever };
278    like($@, qr/Can't find label NOWHERE/, 'goto NOWHERE sets $@');
279}
280
281# see if a modified @_ propagates
282{
283  my $i;
284  package Foo;
285  sub DESTROY	{ my $s = shift; ::is($s->[0], $i, "destroy $i"); }
286  sub show	{ ::is(+@_, 5, "show $i",); }
287  sub start	{ push @_, 1, "foo", {}; goto &show; }
288  for (1..3)	{ $i = $_; start(bless([$_]), 'bar'); }
289}
290
291sub auto {
292    goto &loadit;
293}
294
295sub AUTOLOAD { $ok = 1 if "@_" eq "foo" }
296
297$ok = 0;
298auto("foo");
299ok($ok, 'autoload');
300
301{
302    my $wherever = 'FINALE';
303    goto $wherever;
304}
305fail('goto $wherever');
306
307moretests:
308# test goto duplicated labels.
309{
310    my $z = 0;
311    eval {
312	$z = 0;
313	for (0..1) {
314	  L4: # not outer scope
315	    $z += 10;
316	    last;
317	}
318	goto L4 if $z == 10;
319	last;
320    };
321    like($@, qr/Can't "goto" into the middle of a foreach loop/,
322	    'catch goto middle of foreach');
323
324    $z = 0;
325    # ambiguous label resolution (outer scope means endless loop!)
326  L1:
327    for my $x (0..1) {
328	$z += 10;
329	is($z, 10, 'prefer same scope (loop body) to outer scope (loop entry)');
330	goto L1 unless $x;
331	$z += 10;
332      L1:
333	is($z, 10, 'prefer same scope: second');
334	last;
335    }
336
337    $z = 0;
338  L2:
339    {
340	$z += 10;
341	is($z, 10, 'prefer this scope (block body) to outer scope (block entry)');
342	goto L2 if $z == 10;
343	$z += 10;
344      L2:
345	is($z, 10, 'prefer this scope: second');
346    }
347
348
349    {
350	$z = 0;
351	while (1) {
352	  L3: # not inner scope
353	    $z += 10;
354	    last;
355	}
356	is($z, 10, 'prefer this scope to inner scope');
357	goto L3 if $z == 10;
358	$z += 10;
359      L3: # this scope !
360	is($z, 10, 'prefer this scope to inner scope: second');
361    }
362
363  L4: # not outer scope
364    {
365	$z = 0;
366	while (1) {
367	  L4: # not inner scope
368	    $z += 1;
369	    last;
370	}
371	is($z, 1, 'prefer this scope to inner,outer scopes');
372	goto L4 if $z == 1;
373	$z += 10;
374      L4: # this scope !
375	is($z, 1, 'prefer this scope to inner,outer scopes: second');
376    }
377
378    {
379	my $loop = 0;
380	for my $x (0..1) {
381	  L2: # without this, fails 1 (middle) out of 3 iterations
382	    $z = 0;
383	  L2:
384	    $z += 10;
385	    is($z, 10,
386		"same label, multiple times in same scope (choose 1st) $loop");
387	    goto L2 if $z == 10 and not $loop++;
388	}
389    }
390}
391
392# deep recursion with gotos eventually caused a stack reallocation
393# which messed up buggy internals that didn't expect the stack to move
394
395sub recurse1 {
396    unshift @_, "x";
397    no warnings 'recursion';
398    goto &recurse2;
399}
400sub recurse2 {
401    my $x = shift;
402    $_[0] ? +1 + recurse1($_[0] - 1) : 0
403}
404is(recurse1(500), 500, 'recursive goto &foo');
405
406# [perl #32039] Chained goto &sub drops data too early.
407
408sub a32039 { @_=("foo"); goto &b32039; }
409sub b32039 { goto &c32039; }
410sub c32039 { is($_[0], 'foo', 'chained &goto') }
411a32039();
412
413# [perl #35214] next and redo re-entered the loop with the wrong cop,
414# causing a subsequent goto to crash
415
416{
417    my $r = runperl(
418		stderr => 1,
419		prog =>
420'for ($_=0;$_<3;$_++){A: if($_==1){next} if($_==2){$_++;goto A}}print qq(ok\n)'
421    );
422    is($r, "ok\n", 'next and goto');
423
424    $r = runperl(
425		stderr => 1,
426		prog =>
427'for ($_=0;$_<3;$_++){A: if($_==1){$_++;redo} if($_==2){$_++;goto A}}print qq(ok\n)'
428    );
429    is($r, "ok\n", 'redo and goto');
430}
431
432# goto &foo not allowed in evals
433
434
435sub null { 1 };
436eval 'goto &null';
437like($@, qr/Can't goto subroutine from an eval-string/, 'eval string');
438eval { goto &null };
439like($@, qr/Can't goto subroutine from an eval-block/, 'eval block');
440
441# [perl #36521] goto &foo in warn handler could defeat recursion avoider
442
443{
444    my $r = runperl(
445		stderr => 1,
446		prog => 'my $d; my $w = sub { return if $d++; warn q(bar)}; local $SIG{__WARN__} = sub { goto &$w; }; warn q(foo);'
447    );
448    like($r, qr/bar/, "goto &foo in warn");
449}
450
451TODO: {
452    local $TODO = "[perl #43403] goto() from an if to an else doesn't undo local () changes";
453    our $global = "unmodified";
454    if ($global) { # true but not constant-folded
455         local $global = "modified";
456         goto ELSE;
457    } else {
458         ELSE: is($global, "unmodified");
459    }
460}
461
462