xref: /openbsd-src/gnu/usr.bin/perl/t/op/substr.t (revision 788b9c460cc4af6e96f4595b2d4a4e7fe88e4df0)
1#!./perl -w
2
3#P = start of string  Q = start of substr  R = end of substr  S = end of string
4
5BEGIN {
6    chdir 't' if -d 't';
7    @INC = '../lib';
8}
9use warnings ;
10
11$a = 'abcdefxyz';
12$SIG{__WARN__} = sub {
13     if ($_[0] =~ /^substr outside of string/) {
14          $w++;
15     } elsif ($_[0] =~ /^Attempt to use reference as lvalue in substr/) {
16          $w += 2;
17     } elsif ($_[0] =~ /^Use of uninitialized value/) {
18          $w += 3;
19     } else {
20          warn $_[0];
21     }
22};
23
24require './test.pl';
25
26plan(334);
27
28run_tests() unless caller;
29
30my $krunch = "a";
31
32sub run_tests {
33
34$FATAL_MSG = qr/^substr outside of string/;
35
36is(substr($a,0,3), 'abc');   # P=Q R S
37is(substr($a,3,3), 'def');   # P Q R S
38is(substr($a,6,999), 'xyz'); # P Q S R
39$b = substr($a,999,999) ; # warn # P R Q S
40is ($w--, 1);
41eval{substr($a,999,999) = "" ; };# P R Q S
42like ($@, $FATAL_MSG);
43is(substr($a,0,-6), 'abc');  # P=Q R S
44is(substr($a,-3,1), 'x');    # P Q R S
45
46$[ = 1;
47
48is(substr($a,1,3), 'abc' );  # P=Q R S
49is(substr($a,4,3), 'def' );  # P Q R S
50is(substr($a,7,999), 'xyz');# P Q S R
51$b = substr($a,999,999) ; # warn # P R Q S
52is($w--, 1);
53eval{substr($a,999,999) = "" ; } ; # P R Q S
54like ($@, $FATAL_MSG);
55is(substr($a,1,-6), 'abc' );# P=Q R S
56is(substr($a,-3,1), 'x' );  # P Q R S
57
58$[ = 0;
59
60substr($a,3,3) = 'XYZ';
61is($a, 'abcXYZxyz' );
62substr($a,0,2) = '';
63is($a, 'cXYZxyz' );
64substr($a,0,0) = 'ab';
65is($a, 'abcXYZxyz' );
66substr($a,0,0) = '12345678';
67is($a, '12345678abcXYZxyz' );
68substr($a,-3,3) = 'def';
69is($a, '12345678abcXYZdef');
70substr($a,-3,3) = '<';
71is($a, '12345678abcXYZ<' );
72substr($a,-1,1) = '12345678';
73is($a, '12345678abcXYZ12345678' );
74
75$a = 'abcdefxyz';
76
77is(substr($a,6), 'xyz' );        # P Q R=S
78is(substr($a,-3), 'xyz' );       # P Q R=S
79$b = substr($a,999,999) ; # warning   # P R=S Q
80is($w--, 1);
81eval{substr($a,999,999) = "" ; } ;    # P R=S Q
82like($@, $FATAL_MSG);
83is(substr($a,0), 'abcdefxyz');  # P=Q R=S
84is(substr($a,9), '');           # P Q=R=S
85is(substr($a,-11), 'abcdefxyz'); # Q P R=S
86is(substr($a,-9), 'abcdefxyz');  # P=Q R=S
87
88$a = '54321';
89
90$b = substr($a,-7, 1) ; # warn  # Q R P S
91is($w--, 1);
92eval{substr($a,-7, 1) = "" ; }; # Q R P S
93like($@, $FATAL_MSG);
94$b = substr($a,-7,-6) ; # warn  # Q R P S
95is($w--, 1);
96eval{substr($a,-7,-6) = "" ; }; # Q R P S
97like($@, $FATAL_MSG);
98is(substr($a,-5,-7), '');  # R P=Q S
99is(substr($a, 2,-7), '');  # R P Q S
100is(substr($a,-3,-7), '');  # R P Q S
101is(substr($a, 2,-5), '');  # P=R Q S
102is(substr($a,-3,-5), '');  # P=R Q S
103is(substr($a, 2,-4), '');  # P R Q S
104is(substr($a,-3,-4), '');  # P R Q S
105is(substr($a, 5,-6), '');  # R P Q=S
106is(substr($a, 5,-5), '');  # P=R Q S
107is(substr($a, 5,-3), '');  # P R Q=S
108$b = substr($a, 7,-7) ; # warn  # R P S Q
109is($w--, 1);
110eval{substr($a, 7,-7) = "" ; }; # R P S Q
111like($@, $FATAL_MSG);
112$b = substr($a, 7,-5) ; # warn  # P=R S Q
113is($w--, 1);
114eval{substr($a, 7,-5) = "" ; }; # P=R S Q
115like($@, $FATAL_MSG);
116$b = substr($a, 7,-3) ; # warn  # P Q S Q
117is($w--, 1);
118eval{substr($a, 7,-3) = "" ; }; # P Q S Q
119like($@, $FATAL_MSG);
120$b = substr($a, 7, 0) ; # warn  # P S Q=R
121is($w--, 1);
122eval{substr($a, 7, 0) = "" ; }; # P S Q=R
123like($@, $FATAL_MSG);
124
125is(substr($a,-7,2), '');   # Q P=R S
126is(substr($a,-7,4), '54'); # Q P R S
127is(substr($a,-7,7), '54321');# Q P R=S
128is(substr($a,-7,9), '54321');# Q P S R
129is(substr($a,-5,0), '');   # P=Q=R S
130is(substr($a,-5,3), '543');# P=Q R S
131is(substr($a,-5,5), '54321');# P=Q R=S
132is(substr($a,-5,7), '54321');# P=Q S R
133is(substr($a,-3,0), '');   # P Q=R S
134is(substr($a,-3,3), '321');# P Q R=S
135is(substr($a,-2,3), '21'); # P Q S R
136is(substr($a,0,-5), '');   # P=Q=R S
137is(substr($a,2,-3), '');   # P Q=R S
138is(substr($a,0,0), '');    # P=Q=R S
139is(substr($a,0,5), '54321');# P=Q R=S
140is(substr($a,0,7), '54321');# P=Q S R
141is(substr($a,2,0), '');    # P Q=R S
142is(substr($a,2,3), '321'); # P Q R=S
143is(substr($a,5,0), '');    # P Q=R=S
144is(substr($a,5,2), '');    # P Q=S R
145is(substr($a,-7,-5), '');  # Q P=R S
146is(substr($a,-7,-2), '543');# Q P R S
147is(substr($a,-5,-5), '');  # P=Q=R S
148is(substr($a,-5,-2), '543');# P=Q R S
149is(substr($a,-3,-3), '');  # P Q=R S
150is(substr($a,-3,-1), '32');# P Q R S
151
152$a = '';
153
154is(substr($a,-2,2), '');   # Q P=R=S
155is(substr($a,0,0), '');    # P=Q=R=S
156is(substr($a,0,1), '');    # P=Q=S R
157is(substr($a,-2,3), '');   # Q P=S R
158is(substr($a,-2), '');     # Q P=R=S
159is(substr($a,0), '');      # P=Q=R=S
160
161
162is(substr($a,0,-1), '');   # R P=Q=S
163$b = substr($a,-2, 0) ; # warn  # Q=R P=S
164is($w--, 1);
165eval{substr($a,-2, 0) = "" ; }; # Q=R P=S
166like($@, $FATAL_MSG);
167
168$b = substr($a,-2, 1) ; # warn  # Q R P=S
169is($w--, 1);
170eval{substr($a,-2, 1) = "" ; }; # Q R P=S
171like($@, $FATAL_MSG);
172
173$b = substr($a,-2,-1) ; # warn  # Q R P=S
174is($w--, 1);
175eval{substr($a,-2,-1) = "" ; }; # Q R P=S
176like($@, $FATAL_MSG);
177
178$b = substr($a,-2,-2) ; # warn  # Q=R P=S
179is($w--, 1);
180eval{substr($a,-2,-2) = "" ; }; # Q=R P=S
181like($@, $FATAL_MSG);
182
183$b = substr($a, 1,-2) ; # warn  # R P=S Q
184is($w--, 1);
185eval{substr($a, 1,-2) = "" ; }; # R P=S Q
186like($@, $FATAL_MSG);
187
188$b = substr($a, 1, 1) ; # warn  # P=S Q R
189is($w--, 1);
190eval{substr($a, 1, 1) = "" ; }; # P=S Q R
191like($@, $FATAL_MSG);
192
193$b = substr($a, 1, 0) ;# warn   # P=S Q=R
194is($w--, 1);
195eval{substr($a, 1, 0) = "" ; }; # P=S Q=R
196like($@, $FATAL_MSG);
197
198$b = substr($a,1) ; # warning   # P=R=S Q
199is($w--, 1);
200eval{substr($a,1) = "" ; };     # P=R=S Q
201like($@, $FATAL_MSG);
202
203my $a = 'zxcvbnm';
204substr($a,2,0) = '';
205is($a, 'zxcvbnm');
206substr($a,7,0) = '';
207is($a, 'zxcvbnm');
208substr($a,5,0) = '';
209is($a, 'zxcvbnm');
210substr($a,0,2) = 'pq';
211is($a, 'pqcvbnm');
212substr($a,2,0) = 'r';
213is($a, 'pqrcvbnm');
214substr($a,8,0) = 'asd';
215is($a, 'pqrcvbnmasd');
216substr($a,0,2) = 'iop';
217is($a, 'ioprcvbnmasd');
218substr($a,0,5) = 'fgh';
219is($a, 'fghvbnmasd');
220substr($a,3,5) = 'jkl';
221is($a, 'fghjklsd');
222substr($a,3,2) = '1234';
223is($a, 'fgh1234lsd');
224
225
226# with lexicals (and in re-entered scopes)
227for (0,1) {
228  my $txt;
229  unless ($_) {
230    $txt = "Foo";
231    substr($txt, -1) = "X";
232    is($txt, "FoX");
233  }
234  else {
235    substr($txt, 0, 1) = "X";
236    is($txt, "X");
237  }
238}
239
240$w = 0 ;
241# coercion of references
242{
243  my $s = [];
244  substr($s, 0, 1) = 'Foo';
245  is (substr($s,0,7), "FooRRAY");
246  is ($w,2);
247  $w = 0;
248}
249
250# check no spurious warnings
251is($w, 0);
252
253# check new 4 arg replacement syntax
254$a = "abcxyz";
255$w = 0;
256is(substr($a, 0, 3, ""), "abc");
257is($a, "xyz");
258is(substr($a, 0, 0, "abc"), "");
259is($a, "abcxyz");
260is(substr($a, 3, -1, ""), "xy");
261is($a, "abcz");
262
263is(substr($a, 3, undef, "xy"), "");
264is($a, "abcxyz");
265is($w, 3);
266
267$w = 0;
268
269is(substr($a, 3, 9999999, ""), "xyz");
270is($a, "abc");
271eval{substr($a, -99, 0, "") };
272like($@, $FATAL_MSG);
273eval{substr($a, 99, 3, "") };
274like($@, $FATAL_MSG);
275
276substr($a, 0, length($a), "foo");
277is ($a, "foo");
278is ($w, 0);
279
280# using 4 arg substr as lvalue is a compile time error
281eval 'substr($a,0,0,"") = "abc"';
282like ($@, qr/Can't modify substr/);
283is ($a, "foo");
284
285$a = "abcdefgh";
286is(sub { shift }->(substr($a, 0, 4, "xxxx")), 'abcd');
287is($a, 'xxxxefgh');
288
289{
290    my $y = 10;
291    $y = "2" . $y;
292    is ($y, 210);
293}
294
295# utf8 sanity
296{
297    my $x = substr("a\x{263a}b",0);
298    is(length($x), 3);
299    $x = substr($x,1,1);
300    is($x, "\x{263a}");
301    $x = $x x 2;
302    is(length($x), 2);
303    substr($x,0,1) = "abcd";
304    is($x, "abcd\x{263a}");
305    is(length($x), 5);
306    $x = reverse $x;
307    is(length($x), 5);
308    is($x, "\x{263a}dcba");
309
310    my $z = 10;
311    $z = "21\x{263a}" . $z;
312    is(length($z), 5);
313    is($z, "21\x{263a}10");
314}
315
316# replacement should work on magical values
317require Tie::Scalar;
318my %data;
319tie $data{'a'}, 'Tie::StdScalar';  # makes $data{'a'} magical
320$data{a} = "firstlast";
321is(substr($data{'a'}, 0, 5, ""), "first");
322is($data{'a'}, "last");
323
324# more utf8
325
326# The following two originally from Ignasi Roca.
327
328$x = "\xF1\xF2\xF3";
329substr($x, 0, 1) = "\x{100}"; # Ignasi had \x{FF}
330is(length($x), 3);
331is($x, "\x{100}\xF2\xF3");
332is(substr($x, 0, 1), "\x{100}");
333is(substr($x, 1, 1), "\x{F2}");
334is(substr($x, 2, 1), "\x{F3}");
335
336$x = "\xF1\xF2\xF3";
337substr($x, 0, 1) = "\x{100}\x{FF}"; # Ignasi had \x{FF}
338is(length($x), 4);
339is($x, "\x{100}\x{FF}\xF2\xF3");
340is(substr($x, 0, 1), "\x{100}");
341is(substr($x, 1, 1), "\x{FF}");
342is(substr($x, 2, 1), "\x{F2}");
343is(substr($x, 3, 1), "\x{F3}");
344
345# more utf8 lval exercise
346
347$x = "\xF1\xF2\xF3";
348substr($x, 0, 2) = "\x{100}\xFF";
349is(length($x), 3);
350is($x, "\x{100}\xFF\xF3");
351is(substr($x, 0, 1), "\x{100}");
352is(substr($x, 1, 1), "\x{FF}");
353is(substr($x, 2, 1), "\x{F3}");
354
355$x = "\xF1\xF2\xF3";
356substr($x, 1, 1) = "\x{100}\xFF";
357is(length($x), 4);
358is($x, "\xF1\x{100}\xFF\xF3");
359is(substr($x, 0, 1), "\x{F1}");
360is(substr($x, 1, 1), "\x{100}");
361is(substr($x, 2, 1), "\x{FF}");
362is(substr($x, 3, 1), "\x{F3}");
363
364$x = "\xF1\xF2\xF3";
365substr($x, 2, 1) = "\x{100}\xFF";
366is(length($x), 4);
367is($x, "\xF1\xF2\x{100}\xFF");
368is(substr($x, 0, 1), "\x{F1}");
369is(substr($x, 1, 1), "\x{F2}");
370is(substr($x, 2, 1), "\x{100}");
371is(substr($x, 3, 1), "\x{FF}");
372
373$x = "\xF1\xF2\xF3";
374substr($x, 3, 1) = "\x{100}\xFF";
375is(length($x), 5);
376is($x, "\xF1\xF2\xF3\x{100}\xFF");
377is(substr($x, 0, 1), "\x{F1}");
378is(substr($x, 1, 1), "\x{F2}");
379is(substr($x, 2, 1), "\x{F3}");
380is(substr($x, 3, 1), "\x{100}");
381is(substr($x, 4, 1), "\x{FF}");
382
383$x = "\xF1\xF2\xF3";
384substr($x, -1, 1) = "\x{100}\xFF";
385is(length($x), 4);
386is($x, "\xF1\xF2\x{100}\xFF");
387is(substr($x, 0, 1), "\x{F1}");
388is(substr($x, 1, 1), "\x{F2}");
389is(substr($x, 2, 1), "\x{100}");
390is(substr($x, 3, 1), "\x{FF}");
391
392$x = "\xF1\xF2\xF3";
393substr($x, -1, 0) = "\x{100}\xFF";
394is(length($x), 5);
395is($x, "\xF1\xF2\x{100}\xFF\xF3");
396is(substr($x, 0, 1), "\x{F1}");
397is(substr($x, 1, 1), "\x{F2}");
398is(substr($x, 2, 1), "\x{100}");
399is(substr($x, 3, 1), "\x{FF}");
400is(substr($x, 4, 1), "\x{F3}");
401
402$x = "\xF1\xF2\xF3";
403substr($x, 0, -1) = "\x{100}\xFF";
404is(length($x), 3);
405is($x, "\x{100}\xFF\xF3");
406is(substr($x, 0, 1), "\x{100}");
407is(substr($x, 1, 1), "\x{FF}");
408is(substr($x, 2, 1), "\x{F3}");
409
410$x = "\xF1\xF2\xF3";
411substr($x, 0, -2) = "\x{100}\xFF";
412is(length($x), 4);
413is($x, "\x{100}\xFF\xF2\xF3");
414is(substr($x, 0, 1), "\x{100}");
415is(substr($x, 1, 1), "\x{FF}");
416is(substr($x, 2, 1), "\x{F2}");
417is(substr($x, 3, 1), "\x{F3}");
418
419$x = "\xF1\xF2\xF3";
420substr($x, 0, -3) = "\x{100}\xFF";
421is(length($x), 5);
422is($x, "\x{100}\xFF\xF1\xF2\xF3");
423is(substr($x, 0, 1), "\x{100}");
424is(substr($x, 1, 1), "\x{FF}");
425is(substr($x, 2, 1), "\x{F1}");
426is(substr($x, 3, 1), "\x{F2}");
427is(substr($x, 4, 1), "\x{F3}");
428
429$x = "\xF1\xF2\xF3";
430substr($x, 1, -1) = "\x{100}\xFF";
431is(length($x), 4);
432is($x, "\xF1\x{100}\xFF\xF3");
433is(substr($x, 0, 1), "\x{F1}");
434is(substr($x, 1, 1), "\x{100}");
435is(substr($x, 2, 1), "\x{FF}");
436is(substr($x, 3, 1), "\x{F3}");
437
438$x = "\xF1\xF2\xF3";
439substr($x, -1, -1) = "\x{100}\xFF";
440is(length($x), 5);
441is($x, "\xF1\xF2\x{100}\xFF\xF3");
442is(substr($x, 0, 1), "\x{F1}");
443is(substr($x, 1, 1), "\x{F2}");
444is(substr($x, 2, 1), "\x{100}");
445is(substr($x, 3, 1), "\x{FF}");
446is(substr($x, 4, 1), "\x{F3}");
447
448# And tests for already-UTF8 one
449
450$x = "\x{101}\x{F2}\x{F3}";
451substr($x, 0, 1) = "\x{100}";
452is(length($x), 3);
453is($x, "\x{100}\xF2\xF3");
454is(substr($x, 0, 1), "\x{100}");
455is(substr($x, 1, 1), "\x{F2}");
456is(substr($x, 2, 1), "\x{F3}");
457
458$x = "\x{101}\x{F2}\x{F3}";
459substr($x, 0, 1) = "\x{100}\x{FF}";
460is(length($x), 4);
461is($x, "\x{100}\x{FF}\xF2\xF3");
462is(substr($x, 0, 1), "\x{100}");
463is(substr($x, 1, 1), "\x{FF}");
464is(substr($x, 2, 1), "\x{F2}");
465is(substr($x, 3, 1), "\x{F3}");
466
467$x = "\x{101}\x{F2}\x{F3}";
468substr($x, 0, 2) = "\x{100}\xFF";
469is(length($x), 3);
470is($x, "\x{100}\xFF\xF3");
471is(substr($x, 0, 1), "\x{100}");
472is(substr($x, 1, 1), "\x{FF}");
473is(substr($x, 2, 1), "\x{F3}");
474
475$x = "\x{101}\x{F2}\x{F3}";
476substr($x, 1, 1) = "\x{100}\xFF";
477is(length($x), 4);
478is($x, "\x{101}\x{100}\xFF\xF3");
479is(substr($x, 0, 1), "\x{101}");
480is(substr($x, 1, 1), "\x{100}");
481is(substr($x, 2, 1), "\x{FF}");
482is(substr($x, 3, 1), "\x{F3}");
483
484$x = "\x{101}\x{F2}\x{F3}";
485substr($x, 2, 1) = "\x{100}\xFF";
486is(length($x), 4);
487is($x, "\x{101}\xF2\x{100}\xFF");
488is(substr($x, 0, 1), "\x{101}");
489is(substr($x, 1, 1), "\x{F2}");
490is(substr($x, 2, 1), "\x{100}");
491is(substr($x, 3, 1), "\x{FF}");
492
493$x = "\x{101}\x{F2}\x{F3}";
494substr($x, 3, 1) = "\x{100}\xFF";
495is(length($x), 5);
496is($x, "\x{101}\x{F2}\x{F3}\x{100}\xFF");
497is(substr($x, 0, 1), "\x{101}");
498is(substr($x, 1, 1), "\x{F2}");
499is(substr($x, 2, 1), "\x{F3}");
500is(substr($x, 3, 1), "\x{100}");
501is(substr($x, 4, 1), "\x{FF}");
502
503$x = "\x{101}\x{F2}\x{F3}";
504substr($x, -1, 1) = "\x{100}\xFF";
505is(length($x), 4);
506is($x, "\x{101}\xF2\x{100}\xFF");
507is(substr($x, 0, 1), "\x{101}");
508is(substr($x, 1, 1), "\x{F2}");
509is(substr($x, 2, 1), "\x{100}");
510is(substr($x, 3, 1), "\x{FF}");
511
512$x = "\x{101}\x{F2}\x{F3}";
513substr($x, -1, 0) = "\x{100}\xFF";
514is(length($x), 5);
515is($x, "\x{101}\xF2\x{100}\xFF\xF3");
516is(substr($x, 0, 1), "\x{101}");
517is(substr($x, 1, 1), "\x{F2}");
518is(substr($x, 2, 1), "\x{100}");
519is(substr($x, 3, 1), "\x{FF}");
520is(substr($x, 4, 1), "\x{F3}");
521
522$x = "\x{101}\x{F2}\x{F3}";
523substr($x, 0, -1) = "\x{100}\xFF";
524is(length($x), 3);
525is($x, "\x{100}\xFF\xF3");
526is(substr($x, 0, 1), "\x{100}");
527is(substr($x, 1, 1), "\x{FF}");
528is(substr($x, 2, 1), "\x{F3}");
529
530$x = "\x{101}\x{F2}\x{F3}";
531substr($x, 0, -2) = "\x{100}\xFF";
532is(length($x), 4);
533is($x, "\x{100}\xFF\xF2\xF3");
534is(substr($x, 0, 1), "\x{100}");
535is(substr($x, 1, 1), "\x{FF}");
536is(substr($x, 2, 1), "\x{F2}");
537is(substr($x, 3, 1), "\x{F3}");
538
539$x = "\x{101}\x{F2}\x{F3}";
540substr($x, 0, -3) = "\x{100}\xFF";
541is(length($x), 5);
542is($x, "\x{100}\xFF\x{101}\x{F2}\x{F3}");
543is(substr($x, 0, 1), "\x{100}");
544is(substr($x, 1, 1), "\x{FF}");
545is(substr($x, 2, 1), "\x{101}");
546is(substr($x, 3, 1), "\x{F2}");
547is(substr($x, 4, 1), "\x{F3}");
548
549$x = "\x{101}\x{F2}\x{F3}";
550substr($x, 1, -1) = "\x{100}\xFF";
551is(length($x), 4);
552is($x, "\x{101}\x{100}\xFF\xF3");
553is(substr($x, 0, 1), "\x{101}");
554is(substr($x, 1, 1), "\x{100}");
555is(substr($x, 2, 1), "\x{FF}");
556is(substr($x, 3, 1), "\x{F3}");
557
558$x = "\x{101}\x{F2}\x{F3}";
559substr($x, -1, -1) = "\x{100}\xFF";
560is(length($x), 5);
561is($x, "\x{101}\xF2\x{100}\xFF\xF3");
562is(substr($x, 0, 1), "\x{101}");
563is(substr($x, 1, 1), "\x{F2}");
564is(substr($x, 2, 1), "\x{100}");
565is(substr($x, 3, 1), "\x{FF}");
566is(substr($x, 4, 1), "\x{F3}");
567
568substr($x = "ab", 0, 0, "\x{100}\x{200}");
569is($x, "\x{100}\x{200}ab");
570
571substr($x = "\x{100}\x{200}", 0, 0, "ab");
572is($x, "ab\x{100}\x{200}");
573
574substr($x = "ab", 1, 0, "\x{100}\x{200}");
575is($x, "a\x{100}\x{200}b");
576
577substr($x = "\x{100}\x{200}", 1, 0, "ab");
578is($x, "\x{100}ab\x{200}");
579
580substr($x = "ab", 2, 0, "\x{100}\x{200}");
581is($x, "ab\x{100}\x{200}");
582
583substr($x = "\x{100}\x{200}", 2, 0, "ab");
584is($x, "\x{100}\x{200}ab");
585
586substr($x = "\xFFb", 0, 0, "\x{100}\x{200}");
587is($x, "\x{100}\x{200}\xFFb");
588
589substr($x = "\x{100}\x{200}", 0, 0, "\xFFb");
590is($x, "\xFFb\x{100}\x{200}");
591
592substr($x = "\xFFb", 1, 0, "\x{100}\x{200}");
593is($x, "\xFF\x{100}\x{200}b");
594
595substr($x = "\x{100}\x{200}", 1, 0, "\xFFb");
596is($x, "\x{100}\xFFb\x{200}");
597
598substr($x = "\xFFb", 2, 0, "\x{100}\x{200}");
599is($x, "\xFFb\x{100}\x{200}");
600
601substr($x = "\x{100}\x{200}", 2, 0, "\xFFb");
602is($x, "\x{100}\x{200}\xFFb");
603
604# [perl #20933]
605{
606    my $s = "ab";
607    my @r;
608    $r[$_] = \ substr $s, $_, 1 for (0, 1);
609    is(join("", map { $$_ } @r), "ab");
610}
611
612# [perl #23207]
613{
614    sub ss {
615	substr($_[0],0,1) ^= substr($_[0],1,1) ^=
616	substr($_[0],0,1) ^= substr($_[0],1,1);
617    }
618    my $x = my $y = 'AB'; ss $x; ss $y;
619    is($x, $y);
620}
621
622# [perl #24605]
623{
624    my $x = "0123456789\x{500}";
625    my $y = substr $x, 4;
626    is(substr($x, 7, 1), "7");
627}
628
629# multiple assignments to lvalue [perl #24346]
630{
631    my $x = "abcdef";
632    for (substr($x,1,3)) {
633	is($_, 'bcd');
634	$_ = 'XX';
635	is($_, 'XX');
636	is($x, 'aXXef');
637	$_ = "\xFF";
638	is($_, "\xFF");
639	is($x, "a\xFFef");
640	$_ = "\xF1\xF2\xF3\xF4\xF5\xF6";
641	is($_, "\xF1\xF2\xF3\xF4\xF5\xF6");
642	is($x, "a\xF1\xF2\xF3\xF4\xF5\xF6ef");
643	$_ = 'YYYY';
644	is($_, 'YYYY');
645	is($x, 'aYYYYef');
646    }
647}
648
649# [perl #24200] string corruption with lvalue sub
650
651{
652    sub bar: lvalue { substr $krunch, 0 }
653    bar = "XXX";
654    is(bar, 'XXX');
655    $krunch = '123456789';
656    is(bar, '123456789');
657}
658
659# [perl #29149]
660{
661    my $text  = "0123456789\xED ";
662    utf8::upgrade($text);
663    my $pos = 5;
664    pos($text) = $pos;
665    my $a = substr($text, $pos, $pos);
666    is(substr($text,$pos,1), $pos);
667
668}
669
670# [perl #23765]
671{
672    my $a = pack("C", 0xbf);
673    substr($a, -1) &= chr(0xfeff);
674    is($a, "\xbf");
675}
676
677# [perl #34976] incorrect caching of utf8 substr length
678{
679    my  $a = "abcd\x{100}";
680    is(substr($a,1,2), 'bc');
681    is(substr($a,1,1), 'b');
682}
683
684}
685