12 is( join(':',@x), '1:2:3', 'join an array with character');
14 is( join('',1,2,3), '123', 'join list with no separator');
16 is( join(':',split(/ /,"1 2 3")), '1:2:3', 'join implicit array with character');
19 $f = join ',', 'b', $f, 'e';
20 is( $f, 'b,a,e', 'join list back to self, middle of list');
23 $f = join ',', $f, 'b', 'e';
24 is( $f, 'a,b,e', 'join list back to self, beginning of list');
27 $f = join $f, 'b', 'e', 'k';
28 is( $f, 'baeak', 'join back to self, self is join character');
30 # 7,8 check for multiple read of tied objects
32 sub TIESCALAR { my $x = 7; bless \$x };
33 sub FETCH { my $y = shift; $$y += 5 };
35 my $r = join ':', $t, 99, $t, 99;
36 main::is($r, '12:99:17:99', 'check for multiple read of tied objects, with separator');
37 $r = join '', $t, 99, $t, 99;
38 main::is($r, '22992799', 'check for multiple read of tied objects, w/o separator, and magic');
41 # 9,10 and for multiple read of undef
43 local ($^W, $SIG{__WARN__}) = ( 1, sub { $s+=4 } );
44 my $r = join ':', 'a', undef, $s, 'b', undef, $s, 'c';
45 is( $r, 'a::9:b::13:c', 'multiple read of undef, with separator');
46 my $r = join '', 'a', undef, $s, 'b', undef, $s, 'c';
47 is( $r, 'a17b21c', '... and without separator');
50 { my $s = join("", chr(0x1234), chr(0xff));
51 is( $s, "\x{1234}\x{ff}", 'join two characters with multiple bytes, get two characters');
54 { my $s = join(chr(0xff), chr(0x1234), "");
55 is( $s, "\x{1234}\x{ff}", 'high byte character as separator, 1 multi-byte character in front');
58 { my $s = join(chr(0x1234), chr(0xff), chr(0x2345));
59 is( $s, "\x{ff}\x{1234}\x{2345}", 'multibyte character as separator');
62 { my $s = join(chr(0xff), chr(0x1234), chr(0xfe));
63 is( $s, "\x{1234}\x{ff}\x{fe}", 'high byte as separator, multi-byte and high byte list');
66 { my $s = join('x', ());
67 is( $s, '', 'join should return empty string for empty list');
70 { my $s = join('', ());
71 is( $s, '', 'join should return empty string for empty list and empty separator as well');
75 local $SIG{__WARN__} = sub { $w = shift };
76 use warnings "uninitialized";
77 my $s = join(undef, ());
78 is( $s, '', 'join should return empty string for empty list, when separator is undef');
79 # this warning isn't normative, the implementation may choose to
80 # not evaluate the separator as a string if the list has fewer than
82 like $w, qr/^Use of uninitialized value in join/, "should warn if separator is undef";
86 { # [perl #24846] $jb2 should be in bytes, not in utf8.
88 my $u = "abc\x{0100}";
90 sub join_into_my_variable {
97 return $_[0] eq $_[1] ? pass($_[2]) : fail($_[2]);
100 my $jb1 = join_into_my_variable("", $b);
101 my $ju1 = join_into_my_variable("", $u);
102 my $jb2 = join_into_my_variable("", $b);
103 my $ju2 = join_into_my_variable("", $u);
105 note( 'utf8 and byte checks, perl #24846' );
120 package o { use overload q|""| => sub { ${$_[0]}++ } }
122 my $o = bless \(my $dummy = "a"), o::;
124 is $_, "1a2a3a4a5a6a7a8a9a10", 'join, $overloaded, LIST';
125 is $$o, "b", 'overloading was called once on overloaded separator';
128 for(1,2) { push @_, \join "x", 1 }
130 'join(const, const) still returns a new scalar each time';