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[perl #72724] explicit return doesn’t work with lvalue subs
[perl5.git] / t / op / sub_lval.t
CommitLineData
cd06dffe
GS
1BEGIN {
2 chdir 't' if -d 't';
20822f61 3 @INC = '../lib';
cb949c37 4 require './test.pl';
cd06dffe 5}
07fd1c9c 6plan tests=>90;
cd06dffe 7
78f9721b
SM
8sub a : lvalue { my $a = 34; ${\(bless \$a)} } # Return a temporary
9sub b : lvalue { ${\shift} }
cd06dffe
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10
11my $out = a(b()); # Check that temporaries are allowed.
cb949c37 12is(ref $out, 'main'); # Not reached if error.
cd06dffe
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13
14my @out = grep /main/, a(b()); # Check that temporaries are allowed.
cb949c37 15cmp_ok(scalar @out, '==', 1); # Not reached if error.
cd06dffe
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16
17my $in;
18
19# Check that we can return localized values from subroutines:
20
a98df962
GS
21sub in : lvalue { $in = shift; }
22sub neg : lvalue { #(num_str) return num_str
cd06dffe
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23 local $_ = shift;
24 s/^\+/-/;
25 $_;
26}
27in(neg("+2"));
28
29
cb949c37 30is($in, '-2');
cd06dffe 31
a98df962
GS
32sub get_lex : lvalue { $in }
33sub get_st : lvalue { $blah }
78f9721b 34sub id : lvalue { ${\shift} }
a98df962 35sub id1 : lvalue { $_[0] }
78f9721b 36sub inc : lvalue { ${\++$_[0]} }
cd06dffe
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37
38$in = 5;
39$blah = 3;
40
41get_st = 7;
42
cb949c37 43cmp_ok($blah, '==', 7);
cd06dffe
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44
45get_lex = 7;
46
cb949c37 47cmp_ok($in, '==', 7);
cd06dffe
GS
48
49++get_st;
50
cb949c37 51cmp_ok($blah, '==', 8);
cd06dffe
GS
52
53++get_lex;
54
cb949c37 55cmp_ok($in, '==', 8);
cd06dffe
GS
56
57id(get_st) = 10;
58
cb949c37 59cmp_ok($blah, '==', 10);
cd06dffe
GS
60
61id(get_lex) = 10;
62
cb949c37 63cmp_ok($in, '==', 10);
cd06dffe
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64
65++id(get_st);
66
cb949c37 67cmp_ok($blah, '==', 11);
cd06dffe
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68
69++id(get_lex);
70
cb949c37 71cmp_ok($in, '==', 11);
cd06dffe
GS
72
73id1(get_st) = 20;
74
cb949c37 75cmp_ok($blah, '==', 20);
cd06dffe
GS
76
77id1(get_lex) = 20;
78
cb949c37 79cmp_ok($in, '==', 20);
cd06dffe
GS
80
81++id1(get_st);
82
cb949c37 83cmp_ok($blah, '==', 21);
cd06dffe
GS
84
85++id1(get_lex);
86
cb949c37 87cmp_ok($in, '==', 21);
cd06dffe
GS
88
89inc(get_st);
90
cb949c37 91cmp_ok($blah, '==', 22);
cd06dffe
GS
92
93inc(get_lex);
94
cb949c37 95cmp_ok($in, '==', 22);
cd06dffe
GS
96
97inc(id(get_st));
98
cb949c37 99cmp_ok($blah, '==', 23);
cd06dffe
GS
100
101inc(id(get_lex));
102
cb949c37 103cmp_ok($in, '==', 23);
cd06dffe
GS
104
105++inc(id1(id(get_st)));
106
cb949c37 107cmp_ok($blah, '==', 25);
cd06dffe
GS
108
109++inc(id1(id(get_lex)));
110
cb949c37 111cmp_ok($in, '==', 25);
cd06dffe
GS
112
113@a = (1) x 3;
114@b = (undef) x 2;
115$#c = 3; # These slots are not fillable.
116
117# Explanation: empty slots contain &sv_undef.
118
119=for disabled constructs
120
a98df962
GS
121sub a3 :lvalue {@a}
122sub b2 : lvalue {@b}
123sub c4: lvalue {@c}
cd06dffe
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124
125$_ = '';
126
127eval <<'EOE' or $_ = $@;
128 ($x, a3, $y, b2, $z, c4, $t) = (34 .. 78);
129 1;
130EOE
131
132#@out = ($x, a3, $y, b2, $z, c4, $t);
133#@in = (34 .. 41, (undef) x 4, 46);
134#print "# `@out' ne `@in'\nnot " unless "@out" eq "@in";
135
cb949c37
NC
136like($_, qr/Can\'t return an uninitialized value from lvalue subroutine/);
137print "ok 22\n";
138
cd06dffe
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139=cut
140
cd06dffe
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141
142my $var;
143
a98df962 144sub a::var : lvalue { $var }
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145
146"a"->var = 45;
147
cb949c37 148cmp_ok($var, '==', 45);
cd06dffe
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149
150my $oo;
151$o = bless \$oo, "a";
152
153$o->var = 47;
154
cb949c37 155cmp_ok($var, '==', 47);
cd06dffe 156
a98df962 157sub o : lvalue { $o }
cd06dffe
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158
159o->var = 49;
160
cb949c37 161cmp_ok($var, '==', 49);
cd06dffe
GS
162
163sub nolv () { $x0, $x1 } # Not lvalue
164
165$_ = '';
166
167eval <<'EOE' or $_ = $@;
168 nolv = (2,3);
169 1;
170EOE
171
cb949c37 172like($_, qr/Can\'t modify non-lvalue subroutine call in scalar assignment/);
cd06dffe
GS
173
174$_ = '';
175
176eval <<'EOE' or $_ = $@;
177 nolv = (2,3) if $_;
178 1;
179EOE
180
cb949c37 181like($_, qr/Can\'t modify non-lvalue subroutine call in scalar assignment/);
cd06dffe
GS
182
183$_ = '';
184
185eval <<'EOE' or $_ = $@;
186 &nolv = (2,3) if $_;
187 1;
188EOE
189
cb949c37 190like($_, qr/Can\'t modify non-lvalue subroutine call in scalar assignment/);
cd06dffe
GS
191
192$x0 = $x1 = $_ = undef;
193$nolv = \&nolv;
194
195eval <<'EOE' or $_ = $@;
196 $nolv->() = (2,3) if $_;
197 1;
198EOE
199
cb949c37 200ok(!defined $_) or diag "'$_', '$x0', '$x1'";
cd06dffe
GS
201
202$x0 = $x1 = $_ = undef;
203$nolv = \&nolv;
204
205eval <<'EOE' or $_ = $@;
206 $nolv->() = (2,3);
207 1;
208EOE
209
cb949c37
NC
210like($_, qr/Can\'t modify non-lvalue subroutine call/)
211 or diag "'$_', '$x0', '$x1'";
cd06dffe 212
a98df962 213sub lv0 : lvalue { } # Converted to lv10 in scalar context
cd06dffe
GS
214
215$_ = undef;
216eval <<'EOE' or $_ = $@;
217 lv0 = (2,3);
218 1;
219EOE
220
cb949c37 221like($_, qr/Can't return undef from lvalue subroutine/);
cd06dffe 222
a98df962 223sub lv10 : lvalue {}
cd06dffe
GS
224
225$_ = undef;
226eval <<'EOE' or $_ = $@;
227 (lv0) = (2,3);
228 1;
229EOE
230
cb949c37 231ok(!defined $_) or diag $_;
cd06dffe 232
a98df962 233sub lv1u :lvalue { undef }
cd06dffe
GS
234
235$_ = undef;
236eval <<'EOE' or $_ = $@;
237 lv1u = (2,3);
238 1;
239EOE
240
cb949c37 241like($_, qr/Can't return undef from lvalue subroutine/);
cd06dffe
GS
242
243$_ = undef;
244eval <<'EOE' or $_ = $@;
245 (lv1u) = (2,3);
246 1;
247EOE
248
4c8a4e58
JH
249# Fixed by change @10777
250#print "# '$_'.\nnot "
251# unless /Can\'t return an uninitialized value from lvalue subroutine/;
cb949c37 252# print "ok 34 # Skip: removed test\n";
cd06dffe
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253
254$x = '1234567';
cd06dffe
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255
256$_ = undef;
257eval <<'EOE' or $_ = $@;
78f9721b 258 sub lv1t : lvalue { index $x, 2 }
cd06dffe
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259 lv1t = (2,3);
260 1;
261EOE
262
cb949c37 263like($_, qr/Can\'t modify index in lvalue subroutine return/);
cd06dffe
GS
264
265$_ = undef;
266eval <<'EOE' or $_ = $@;
78f9721b
SM
267 sub lv2t : lvalue { shift }
268 (lv2t) = (2,3);
cd06dffe
GS
269 1;
270EOE
271
cb949c37 272like($_, qr/Can\'t modify shift in lvalue subroutine return/);
cd06dffe
GS
273
274$xxx = 'xxx';
275sub xxx () { $xxx } # Not lvalue
cd06dffe
GS
276
277$_ = undef;
278eval <<'EOE' or $_ = $@;
78f9721b 279 sub lv1tmp : lvalue { xxx } # is it a TEMP?
cd06dffe
GS
280 lv1tmp = (2,3);
281 1;
282EOE
283
cb949c37 284like($_, qr/Can\'t modify non-lvalue subroutine call in lvalue subroutine return/);
cd06dffe
GS
285
286$_ = undef;
287eval <<'EOE' or $_ = $@;
288 (lv1tmp) = (2,3);
289 1;
290EOE
291
cb949c37 292like($_, qr/Can\'t return a temporary from lvalue subroutine/);
cd06dffe 293
9a049f1c 294sub yyy () { 'yyy' } # Const, not lvalue
cd06dffe
GS
295
296$_ = undef;
297eval <<'EOE' or $_ = $@;
78f9721b 298 sub lv1tmpr : lvalue { yyy } # is it read-only?
cd06dffe
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299 lv1tmpr = (2,3);
300 1;
301EOE
302
cb949c37 303like($_, qr/Can\'t modify constant item in lvalue subroutine return/);
cd06dffe
GS
304
305$_ = undef;
306eval <<'EOE' or $_ = $@;
307 (lv1tmpr) = (2,3);
308 1;
309EOE
310
cb949c37 311like($_, qr/Can\'t return a readonly value from lvalue subroutine/);
cd06dffe 312
a98df962 313sub lva : lvalue {@a}
cd06dffe
GS
314
315$_ = undef;
316@a = ();
317$a[1] = 12;
318eval <<'EOE' or $_ = $@;
319 (lva) = (2,3);
320 1;
321EOE
322
cb949c37 323is("'@a' $_", "'2 3' ");
cd06dffe
GS
324
325$_ = undef;
326@a = ();
327$a[0] = undef;
328$a[1] = 12;
329eval <<'EOE' or $_ = $@;
330 (lva) = (2,3);
331 1;
332EOE
333
cb949c37 334is("'@a' $_", "'2 3' ");
cd06dffe
GS
335
336$_ = undef;
337@a = ();
338$a[0] = undef;
339$a[1] = 12;
340eval <<'EOE' or $_ = $@;
341 (lva) = (2,3);
342 1;
343EOE
344
cb949c37 345is("'@a' $_", "'2 3' ");
cd06dffe 346
a98df962 347sub lv1n : lvalue { $newvar }
cd06dffe
GS
348
349$_ = undef;
350eval <<'EOE' or $_ = $@;
351 lv1n = (3,4);
352 1;
353EOE
354
cb949c37 355is("'$newvar' $_", "'4' ");
cd06dffe 356
a98df962 357sub lv1nn : lvalue { $nnewvar }
cd06dffe
GS
358
359$_ = undef;
360eval <<'EOE' or $_ = $@;
361 (lv1nn) = (3,4);
362 1;
363EOE
364
cb949c37 365is("'$nnewvar' $_", "'3' ");
cd06dffe
GS
366
367$a = \&lv1nn;
368$a->() = 8;
cb949c37 369is($nnewvar, '8');
d32f2495 370
84251760 371eval 'sub AUTOLOAD : lvalue { $newvar }';
d32f2495 372foobar() = 12;
cb949c37 373is($newvar, "12");
26191e78 374
78f9721b
SM
375{
376my %hash; my @array;
377sub alv : lvalue { $array[1] }
378sub alv2 : lvalue { $array[$_[0]] }
379sub hlv : lvalue { $hash{"foo"} }
380sub hlv2 : lvalue { $hash{$_[0]} }
381$array[1] = "not ok 51\n";
382alv() = "ok 50\n";
cb949c37 383is(alv(), "ok 50\n");
78f9721b
SM
384
385alv2(20) = "ok 51\n";
cb949c37 386is($array[20], "ok 51\n");
78f9721b
SM
387
388$hash{"foo"} = "not ok 52\n";
389hlv() = "ok 52\n";
cb949c37 390is($hash{foo}, "ok 52\n");
78f9721b
SM
391
392$hash{bar} = "not ok 53\n";
393hlv("bar") = "ok 53\n";
cb949c37 394is(hlv("bar"), "ok 53\n");
78f9721b
SM
395
396sub array : lvalue { @array }
397sub array2 : lvalue { @array2 } # This is a global.
398sub hash : lvalue { %hash }
399sub hash2 : lvalue { %hash2 } # So's this.
400@array2 = qw(foo bar);
401%hash2 = qw(foo bar);
402
403(array()) = qw(ok 54);
cb949c37 404is("@array", "ok 54");
78f9721b
SM
405
406(array2()) = qw(ok 55);
cb949c37 407is("@array2", "ok 55");
78f9721b
SM
408
409(hash()) = qw(ok 56);
cb949c37 410cmp_ok($hash{ok}, '==', 56);
78f9721b
SM
411
412(hash2()) = qw(ok 57);
cb949c37 413cmp_ok($hash2{ok}, '==', 57);
78f9721b
SM
414
415@array = qw(a b c d);
416sub aslice1 : lvalue { @array[0,2] };
417(aslice1()) = ("ok", "already");
cb949c37 418is("@array", "ok b already d");
78f9721b
SM
419
420@array2 = qw(a B c d);
421sub aslice2 : lvalue { @array2[0,2] };
422(aslice2()) = ("ok", "already");
cb949c37 423is("@array2", "ok B already d");
78f9721b
SM
424
425%hash = qw(a Alpha b Beta c Gamma);
426sub hslice : lvalue { @hash{"c", "b"} }
427(hslice()) = ("CISC", "BogoMIPS");
cb949c37 428is(join("/",@hash{"c","a","b"}), "CISC/Alpha/BogoMIPS");
78f9721b
SM
429}
430
431$str = "Hello, world!";
432sub sstr : lvalue { substr($str, 1, 4) }
433sstr() = "i";
cb949c37 434is($str, "Hi, world!");
78f9721b
SM
435
436$str = "Made w/ JavaScript";
437sub veclv : lvalue { vec($str, 2, 32) }
e6b8b224
PP
438if (ord('A') != 193) {
439 veclv() = 0x5065726C;
440}
441else { # EBCDIC?
442 veclv() = 0xD7859993;
443}
cb949c37 444is($str, "Made w/ PerlScript");
78f9721b
SM
445
446sub position : lvalue { pos }
447@p = ();
448$_ = "fee fi fo fum";
449while (/f/g) {
450 push @p, position;
451 position() += 6;
452}
cb949c37 453is("@p", "1 8");
7c8af4ef
RG
454
455# Bug 20001223.002: split thought that the list had only one element
456@ary = qw(4 5 6);
457sub lval1 : lvalue { $ary[0]; }
458sub lval2 : lvalue { $ary[1]; }
459(lval1(), lval2()) = split ' ', "1 2 3 4";
cb949c37
NC
460
461is(join(':', @ary), "1:2:6");
1c4274f4 462
f9bc45ef
TP
463# check that an element of a tied hash/array can be assigned to via lvalueness
464
465package Tie_Hash;
466
467our ($key, $val);
468sub TIEHASH { bless \my $v => __PACKAGE__ }
469sub STORE { ($key, $val) = @_[1,2] }
470
471package main;
472sub lval_tie_hash : lvalue {
473 tie my %t => 'Tie_Hash';
474 $t{key};
475}
476
477eval { lval_tie_hash() = "value"; };
478
cb949c37 479is($@, "", "element of tied hash");
f9bc45ef 480
cb949c37 481is("$Tie_Hash::key-$Tie_Hash::val", "key-value");
f9bc45ef
TP
482
483
484package Tie_Array;
485
486our @val;
487sub TIEARRAY { bless \my $v => __PACKAGE__ }
488sub STORE { $val[ $_[1] ] = $_[2] }
489
490package main;
491sub lval_tie_array : lvalue {
492 tie my @t => 'Tie_Array';
493 $t[0];
494}
495
496eval { lval_tie_array() = "value"; };
497
f9bc45ef 498
cb949c37 499is($@, "", "element of tied array");
f9bc45ef 500
cb949c37 501is ($Tie_Array::val[0], "value");
1c4274f4 502
1c4274f4 503
fa1e92c4
FC
504# Test explicit return of lvalue expression
505{
506 # subs are copies from tests 1-~18 with an explicit return added.
507 # They used not to work, which is why they are ‘badly’ named.
1c4274f4
MS
508 sub bad_get_lex : lvalue { return $in };
509 sub bad_get_st : lvalue { return $blah }
510
511 sub bad_id : lvalue { return ${\shift} }
512 sub bad_id1 : lvalue { return $_[0] }
513 sub bad_inc : lvalue { return ${\++$_[0]} }
514
515 $in = 5;
516 $blah = 3;
517
518 bad_get_st = 7;
519
520 is( $blah, 7 );
521
522 bad_get_lex = 7;
523
524 is($in, 7, "yada");
525
526 ++bad_get_st;
527
528 is($blah, 8, "yada");
07fd1c9c
FC
529
530 ++bad_get_lex;
531 cmp_ok($in, '==', 8);
532
533 bad_id(bad_get_st) = 10;
534 cmp_ok($blah, '==', 10);
535
536 bad_id(bad_get_lex) = 10;
537 cmp_ok($in, '==', 10);
538
539 ++bad_id(bad_get_st);
540 cmp_ok($blah, '==', 11);
541
542 ++bad_id(bad_get_lex);
543 cmp_ok($in, '==', 11);
544
545 bad_id1(bad_get_st) = 20;
546 cmp_ok($blah, '==', 20);
547
548 bad_id1(bad_get_lex) = 20;
549 cmp_ok($in, '==', 20);
550
551 ++bad_id1(bad_get_st);
552 cmp_ok($blah, '==', 21);
553
554 ++bad_id1(bad_get_lex);
555 cmp_ok($in, '==', 21);
556
557 bad_inc(bad_get_st);
558 cmp_ok($blah, '==', 22);
559
560 bad_inc(bad_get_lex);
561 cmp_ok($in, '==', 22);
562
563 bad_inc(bad_id(bad_get_st));
564 cmp_ok($blah, '==', 23);
565
566 bad_inc(bad_id(bad_get_lex));
567 cmp_ok($in, '==', 23);
568
569 ++bad_inc(bad_id1(bad_id(bad_get_st)));
570 cmp_ok($blah, '==', 25);
571
572 ++bad_inc(bad_id1(bad_id(bad_get_lex)));
573 cmp_ok($in, '==', 25);
1c4274f4
MS
574}
575
91e34d82 576{ # bug #23790
4546bcba
RGS
577 my @arr = qw /one two three/;
578 my $line = "zero";
579 sub lval_array () : lvalue {@arr}
580
581 for (lval_array) {
582 $line .= $_;
583 }
584
585 is($line, "zeroonetwothree");
91e34d82
MP
586
587 sub trythislval { scalar(@_)."x".join "", @_ }
588 is(trythislval(lval_array()), "3xonetwothree");
589
590 sub changeme { $_[2] = "free" }
591 changeme(lval_array);
592 is("@arr", "one two free");
4546bcba 593}
cb0d96b9
NC
594
595{
596 package Foo;
597 sub AUTOLOAD :lvalue { *{$AUTOLOAD} };
598 package main;
599 my $foo = bless {},"Foo";
600 my $result;
601 $foo->bar = sub { $result = "bar" };
602 $foo->bar;
603 is ($result, 'bar', "RT #41550");
604}
885ef6f5
GG
605
606fresh_perl_is(<<'----', <<'====', "lvalue can not be set after definition. [perl #68758]");
607use warnings;
608our $x;
609sub foo { $x }
610sub foo : lvalue;
611foo = 3;
612----
613lvalue attribute ignored after the subroutine has been defined at - line 4.
614Can't modify non-lvalue subroutine call in scalar assignment at - line 5, near "3;"
615Execution of - aborted due to compilation errors.
616====
eac910c8
GG
617
618{
619 my $x;
620 sub lval_decl : lvalue;
621 sub lval_decl { $x }
622 lval_decl = 5;
623 is($x, 5, "subroutine declared with lvalue before definition retains lvalue. [perl #68758]");
624}
f71f472f
FC
625
626sub fleen : lvalue { $pnare }
627$pnare = __PACKAGE__;
628ok eval { fleen = 1 }, "lvalues can return COWs (CATTLE?) [perl #75656]";\
629is $pnare, 1, 'and returning CATTLE actually works';