+#!perl -T
+
+use strict;
+use warnings;
+
+use Test::More tests => 6 * 3 * 240;
+
+sub testcase {
+ my ($var, $init, $code, $exp, $use, $global) = @_;
+ my $decl = $global ? "our $var; local $var;" : "my $var;";
+ my $test = $var =~ /^[@%]/ ? "\\$var" : $var;
+ return <<TESTCASE;
+my \@exp = ($exp);
+$decl
+$init
+my \$res = eval {
+ local \$SIG{__WARN__} = sub { die join '', 'warn:', \@_ };
+ $use
+ $code
+};
+if (ref \$exp[0]) {
+ like \$@, \$exp[0], \$desc . ' [exception]';
+} else {
+ is \$@, \$exp[0], \$desc . ' [exception]';
+}
+is_deeply \$res, \$exp[1], \$desc . ' [return]';
+is_deeply $test, \$exp[2], \$desc . ' [variable]';
+TESTCASE
+}
+
+while (<DATA>) {
+ 1 while chomp;
+ next unless /#/;
+ my @chunks = split /#+/, "$_ ";
+ s/^\s+//, s/\s+$// for @chunks;
+ my ($init, $code, $exp, $opts) = @chunks;
+ (my $var = $init) =~ s/[^\$@%\w].*//;
+ $init = $var eq $init ? '' : "$init;";
+ my $use;
+ if ($opts) {
+ for (split ' ', $opts) {
+ my $no = 1;
+ $no = 0 if s/^([-+])// and $1 eq '-';
+ $use .= ($no ? 'no' : 'use') . " autovivification '$_';"
+ }
+ } elsif (defined $opts) {
+ $opts = 'empty';
+ $use = 'no autovivification;';
+ } else {
+ $opts = 'default';
+ $use = '';
+ }
+ my @testcases = (
+ [ $var, $init, $code, $exp, $use, 0 ],
+ [ $var, "use strict; $init", $code, $exp, $use, 1 ],
+ [ $var, "no strict; $init", $code, $exp, $use, 1 ],
+ );
+ my @extra;
+ for (@testcases) {
+ my $var = $_->[0];
+ if ($var =~ /\$/) {
+ my @new = @$_;
+ $new[0] =~ s/^$/@/;
+ $new[1] =~ s/$var\->/$var/g;
+ $new[2] =~ s/$var\->/$var/g;
+ push @extra, \@new;
+ }
+ }
+ push @testcases, @extra;
+ for (@testcases) {
+ my $testcase = testcase(@$_);
+ my ($var, $init, $code) = @$_;
+ my $desc = do { (my $x = "$var | $init") =~ s,;\s+$,,; $x } . " | $code | $opts";
+ eval $testcase;
+ diag "== This testcase failed to compile ==\n$testcase\n## Reason: $@" if $@;
+ }
+}
+
+__DATA__
+
+--- fetch ---
+
+$x # $x->[0] # '', undef, [ ]
+$x # $x->[0] # '', undef, undef #
+$x # $x->[0] # '', undef, undef # +fetch
+$x # $x->[0] # '', undef, [ ] # +exists
+$x # $x->[0] # '', undef, [ ] # +delete
+$x # $x->[0] # '', undef, [ ] # +store
+
+$x # $x->[0] # qr/^Reference vivification forbidden/, undef, undef # +strict +fetch
+$x # $x->[0] # '', undef, [ ] # +strict +exists
+$x # $x->[0] # '', undef, [ ] # +strict +delete
+$x # $x->[0] # '', undef, [ ] # +strict +store
+
+$x # $x->[0]->[1] # '', undef, [ [ ] ]
+$x # $x->[0]->[1] # '', undef, undef #
+$x # $x->[0]->[1] # '', undef, undef # +fetch
+$x # $x->[0]->[1] # '', undef, [ [ ] ] # +exists
+$x # $x->[0]->[1] # '', undef, [ [ ] ] # +delete
+$x # $x->[0]->[1] # '', undef, [ [ ] ] # +store
+
+$x # $x->[0]->[1] # qr/^Reference vivification forbidden/, undef, undef # +strict +fetch
+$x # $x->[0]->[1] # '', undef, [ [ ] ] # +strict +exists
+$x # $x->[0]->[1] # '', undef, [ [ ] ] # +strict +delete
+$x # $x->[0]->[1] # '', undef, [ [ ] ] # +strict +store
+
+$x->[0] = 1 # $x->[0] # '', 1, [ 1 ] # +fetch
+$x->[0] = 1 # $x->[1] # '', undef, [ 1 ] # +fetch
+$x->[0] = 1 # $x->[0] # '', 1, [ 1 ] # +exists
+$x->[0] = 1 # $x->[1] # '', undef, [ 1 ] # +exists
+$x->[0] = 1 # $x->[0] # '', 1, [ 1 ] # +delete
+$x->[0] = 1 # $x->[1] # '', undef, [ 1 ] # +delete
+$x->[0] = 1 # $x->[0] # '', 1, [ 1 ] # +store
+$x->[0] = 1 # $x->[1] # '', undef, [ 1 ] # +store
+
+$x->[0] = 1 # $x->[0] # '', 1, [ 1 ] # +strict +fetch
+$x->[0] = 1 # $x->[1] # '', undef, [ 1 ] # +strict +fetch
+$x->[0] = 1 # $x->[0] # '', 1, [ 1 ] # +strict +exists
+$x->[0] = 1 # $x->[1] # '', undef, [ 1 ] # +strict +exists
+$x->[0] = 1 # $x->[0] # '', 1, [ 1 ] # +strict +delete
+$x->[0] = 1 # $x->[1] # '', undef, [ 1 ] # +strict +delete
+$x->[0] = 1 # $x->[0] # '', 1, [ 1 ] # +strict +store
+$x->[0] = 1 # $x->[1] # '', undef, [ 1 ] # +strict +store
+
+$x->[0]->[1] = 1 # $x->[0]->[1] # '', 1, [ [ undef, 1 ] ] # +fetch
+$x->[0]->[1] = 1 # $x->[0]->[3] # '', undef, [ [ undef, 1 ] ] # +fetch
+$x->[0]->[1] = 1 # $x->[2]->[3] # '', undef, [ [ undef, 1 ] ] # +fetch
+$x->[0]->[1] = 1 # $x->[0]->[1] # '', 1, [ [ undef, 1 ] ] # +exists
+$x->[0]->[1] = 1 # $x->[0]->[3] # '', undef, [ [ undef, 1 ] ] # +exists
+$x->[0]->[1] = 1 # $x->[2]->[3] # '', undef, [ [ undef, 1 ], undef, [ ] ] # +exists
+$x->[0]->[1] = 1 # $x->[0]->[1] # '', 1, [ [ undef, 1 ] ] # +delete
+$x->[0]->[1] = 1 # $x->[0]->[3] # '', undef, [ [ undef, 1 ] ] # +delete
+$x->[0]->[1] = 1 # $x->[2]->[3] # '', undef, [ [ undef, 1 ], undef, [ ] ] # +delete
+$x->[0]->[1] = 1 # $x->[0]->[1] # '', 1, [ [ undef, 1 ] ] # +store
+$x->[0]->[1] = 1 # $x->[0]->[3] # '', undef, [ [ undef, 1 ] ] # +store
+$x->[0]->[1] = 1 # $x->[2]->[3] # '', undef, [ [ undef, 1 ], undef, [ ] ] # +store
+
+$x->[0]->[1] = 1 # $x->[0]->[1] # '', 1, [ [ undef, 1 ] ] # +strict +fetch
+$x->[0]->[1] = 1 # $x->[0]->[3] # '', undef, [ [ undef, 1 ] ] # +strict +fetch
+$x->[0]->[1] = 1 # $x->[2]->[3] # qr/^Reference vivification forbidden/, undef, [ [ undef, 1 ] ] # +strict +fetch
+$x->[0]->[1] = 1 # $x->[0]->[1] # '', 1, [ [ undef, 1 ] ] # +strict +exists
+$x->[0]->[1] = 1 # $x->[0]->[3] # '', undef, [ [ undef, 1 ] ] # +strict +exists
+$x->[0]->[1] = 1 # $x->[2]->[3] # '', undef, [ [ undef, 1 ], undef, [ ] ] # +strict +exists
+$x->[0]->[1] = 1 # $x->[0]->[1] # '', 1, [ [ undef, 1 ] ] # +strict +delete
+$x->[0]->[1] = 1 # $x->[0]->[3] # '', undef, [ [ undef, 1 ] ] # +strict +delete
+$x->[0]->[1] = 1 # $x->[2]->[3] # '', undef, [ [ undef, 1 ], undef, [ ] ] # +strict +delete
+$x->[0]->[1] = 1 # $x->[0]->[1] # '', 1, [ [ undef, 1 ] ] # +strict +store
+$x->[0]->[1] = 1 # $x->[0]->[3] # '', undef, [ [ undef, 1 ] ] # +strict +store
+$x->[0]->[1] = 1 # $x->[2]->[3] # '', undef, [ [ undef, 1 ], undef, [ ] ] # +strict +store
+
+--- exists ---
+
+$x # exists $x->[0] # '', '', [ ]
+$x # exists $x->[0] # '', '', undef #
+$x # exists $x->[0] # '', '', [ ] # +fetch
+$x # exists $x->[0] # '', '', undef # +exists
+$x # exists $x->[0] # '', '', [ ] # +delete
+$x # exists $x->[0] # '', '', [ ] # +store
+
+$x # exists $x->[0] # '', '', [ ] # +strict +fetch
+$x # exists $x->[0] # qr/^Reference vivification forbidden/, undef, undef # +strict +exists
+$x # exists $x->[0] # '', '', [ ] # +strict +delete
+$x # exists $x->[0] # '', '', [ ] # +strict +store
+
+$x # exists $x->[0]->[1] # '', '', [ [ ] ]
+$x # exists $x->[0]->[1] # '', '', undef #
+$x # exists $x->[0]->[1] # '', '', [ [ ] ] # +fetch
+$x # exists $x->[0]->[1] # '', '', undef # +exists
+$x # exists $x->[0]->[1] # '', '', [ [ ] ] # +delete
+$x # exists $x->[0]->[1] # '', '', [ [ ] ] # +store
+
+$x # exists $x->[0]->[1] # '', '', [ [ ] ] # +strict +fetch
+$x # exists $x->[0]->[1] # qr/^Reference vivification forbidden/, undef, undef # +strict +exists
+$x # exists $x->[0]->[1] # '', '', [ [ ] ] # +strict +delete
+$x # exists $x->[0]->[1] # '', '', [ [ ] ] # +strict +store
+
+$x->[0] = 1 # exists $x->[0] # '', 1, [ 1 ] # +fetch
+$x->[0] = 1 # exists $x->[1] # '', '', [ 1 ] # +fetch
+$x->[0] = 1 # exists $x->[0] # '', 1, [ 1 ] # +exists
+$x->[0] = 1 # exists $x->[1] # '', '', [ 1 ] # +exists
+$x->[0] = 1 # exists $x->[0] # '', 1, [ 1 ] # +delete
+$x->[0] = 1 # exists $x->[1] # '', '', [ 1 ] # +delete
+$x->[0] = 1 # exists $x->[0] # '', 1, [ 1 ] # +store
+$x->[0] = 1 # exists $x->[1] # '', '', [ 1 ] # +store
+
+$x->[0] = 1 # exists $x->[0] # '', 1, [ 1 ] # +strict +fetch
+$x->[0] = 1 # exists $x->[1] # '', '', [ 1 ] # +strict +fetch
+$x->[0] = 1 # exists $x->[0] # '', 1, [ 1 ] # +strict +exists
+$x->[0] = 1 # exists $x->[1] # '', '', [ 1 ] # +strict +exists
+$x->[0] = 1 # exists $x->[0] # '', 1, [ 1 ] # +strict +delete
+$x->[0] = 1 # exists $x->[1] # '', '', [ 1 ] # +strict +delete
+$x->[0] = 1 # exists $x->[0] # '', 1, [ 1 ] # +strict +store
+$x->[0] = 1 # exists $x->[1] # '', '', [ 1 ] # +strict +store
+
+$x->[0]->[1] = 1 # exists $x->[0]->[1] # '', 1, [ [ undef, 1 ] ] # +fetch
+$x->[0]->[1] = 1 # exists $x->[0]->[3] # '', '', [ [ undef, 1 ] ] # +fetch
+$x->[0]->[1] = 1 # exists $x->[2]->[3] # '', '', [ [ undef, 1 ], undef, [ ] ] # +fetch
+$x->[0]->[1] = 1 # exists $x->[0]->[1] # '', 1, [ [ undef, 1 ] ] # +exists
+$x->[0]->[1] = 1 # exists $x->[0]->[3] # '', '', [ [ undef, 1 ] ] # +exists
+$x->[0]->[1] = 1 # exists $x->[2]->[3] # '', '', [ [ undef, 1 ] ] # +exists
+$x->[0]->[1] = 1 # exists $x->[0]->[1] # '', 1, [ [ undef, 1 ] ] # +delete
+$x->[0]->[1] = 1 # exists $x->[0]->[3] # '', '', [ [ undef, 1 ] ] # +delete
+$x->[0]->[1] = 1 # exists $x->[2]->[3] # '', '', [ [ undef, 1 ], undef, [ ] ] # +delete
+$x->[0]->[1] = 1 # exists $x->[0]->[1] # '', 1, [ [ undef, 1 ] ] # +store
+$x->[0]->[1] = 1 # exists $x->[0]->[3] # '', '', [ [ undef, 1 ] ] # +store
+$x->[0]->[1] = 1 # exists $x->[2]->[3] # '', '', [ [ undef, 1 ], undef, [ ] ] # +store
+
+$x->[0]->[1] = 1 # exists $x->[0]->[1] # '', 1, [ [ undef, 1 ] ] # +strict +fetch
+$x->[0]->[1] = 1 # exists $x->[0]->[3] # '', '', [ [ undef, 1 ] ] # +strict +fetch
+$x->[0]->[1] = 1 # exists $x->[2]->[3] # '', '', [ [ undef, 1 ], undef, [ ] ] # +strict +fetch
+$x->[0]->[1] = 1 # exists $x->[0]->[1] # '', 1, [ [ undef, 1 ] ] # +strict +exists
+$x->[0]->[1] = 1 # exists $x->[0]->[3] # '', '', [ [ undef, 1 ] ] # +strict +exists
+$x->[0]->[1] = 1 # exists $x->[2]->[3] # qr/^Reference vivification forbidden/, undef, [ [ undef, 1 ] ] # +strict +exists
+$x->[0]->[1] = 1 # exists $x->[0]->[1] # '', 1, [ [ undef, 1 ] ] # +strict +delete
+$x->[0]->[1] = 1 # exists $x->[0]->[3] # '', '', [ [ undef, 1 ] ] # +strict +delete
+$x->[0]->[1] = 1 # exists $x->[2]->[3] # '', '', [ [ undef, 1 ], undef, [ ] ] # +strict +delete
+$x->[0]->[1] = 1 # exists $x->[0]->[1] # '', 1, [ [ undef, 1 ] ] # +strict +store
+$x->[0]->[1] = 1 # exists $x->[0]->[3] # '', '', [ [ undef, 1 ] ] # +strict +store
+$x->[0]->[1] = 1 # exists $x->[2]->[3] # '', '', [ [ undef, 1 ], undef, [ ] ] # +strict +store
+
+--- delete ---
+
+$x # delete $x->[0] # '', undef, [ ]
+$x # delete $x->[0] # '', undef, undef #
+$x # delete $x->[0] # '', undef, [ ] # +fetch
+$x # delete $x->[0] # '', undef, [ ] # +exists
+$x # delete $x->[0] # '', undef, undef # +delete
+$x # delete $x->[0] # '', undef, [ ] # +store
+
+$x # delete $x->[0] # '', undef, [ ] # +strict +fetch
+$x # delete $x->[0] # '', undef, [ ] # +strict +exists
+$x # delete $x->[0] # qr/^Reference vivification forbidden/, undef, undef # +strict +delete
+$x # delete $x->[0] # '', undef, [ ] # +strict +store
+
+$x # delete $x->[0]->[1] # '', undef, [ [ ] ]
+$x # delete $x->[0]->[1] # '', undef, undef #
+$x # delete $x->[0]->[1] # '', undef, [ [ ] ] # +fetch
+$x # delete $x->[0]->[1] # '', undef, [ [ ] ] # +exists
+$x # delete $x->[0]->[1] # '', undef, undef # +delete
+$x # delete $x->[0]->[1] # '', undef, [ [ ] ] # +store
+
+$x # delete $x->[0]->[1] # '', undef, [ [ ] ] # +strict +fetch
+$x # delete $x->[0]->[1] # '', undef, [ [ ] ] # +strict +exists
+$x # delete $x->[0]->[1] # qr/^Reference vivification forbidden/, undef, undef # +strict +delete
+$x # delete $x->[0]->[1] # '', undef, [ [ ] ] # +strict +store
+
+$x->[0] = 1 # delete $x->[0] # '', 1, [ ] # +fetch
+$x->[0] = 1 # delete $x->[1] # '', undef, [ 1 ] # +fetch
+$x->[0] = 1 # delete $x->[0] # '', 1, [ ] # +exists
+$x->[0] = 1 # delete $x->[1] # '', undef, [ 1 ] # +exists
+$x->[0] = 1 # delete $x->[0] # '', 1, [ ] # +delete
+$x->[0] = 1 # delete $x->[1] # '', undef, [ 1 ] # +delete
+$x->[0] = 1 # delete $x->[0] # '', 1, [ ] # +store
+$x->[0] = 1 # delete $x->[1] # '', undef, [ 1 ] # +store
+
+$x->[0] = 1 # delete $x->[0] # '', 1, [ ] # +strict +fetch
+$x->[0] = 1 # delete $x->[1] # '', undef, [ 1 ] # +strict +fetch
+$x->[0] = 1 # delete $x->[0] # '', 1, [ ] # +strict +exists
+$x->[0] = 1 # delete $x->[1] # '', undef, [ 1 ] # +strict +exists
+$x->[0] = 1 # delete $x->[0] # '', 1, [ ] # +strict +delete
+$x->[0] = 1 # delete $x->[1] # '', undef, [ 1 ] # +strict +delete
+$x->[0] = 1 # delete $x->[0] # '', 1, [ ] # +strict +store
+$x->[0] = 1 # delete $x->[1] # '', undef, [ 1 ] # +strict +store
+
+$x->[0]->[1] = 1 # delete $x->[0]->[1] # '', 1, [ [ ] ] # +fetch
+$x->[0]->[1] = 1 # delete $x->[0]->[3] # '', undef, [ [ undef, 1 ] ]# +fetch
+$x->[0]->[1] = 1 # delete $x->[2]->[3] # '', undef, [ [ undef, 1 ], undef, [ ] ] # +fetch
+$x->[0]->[1] = 1 # delete $x->[0]->[1] # '', 1, [ [ ] ] # +exists
+$x->[0]->[1] = 1 # delete $x->[0]->[3] # '', undef, [ [ undef, 1 ] ]# +exists
+$x->[0]->[1] = 1 # delete $x->[2]->[3] # '', undef, [ [ undef, 1 ], undef, [ ] ] # +exists
+$x->[0]->[1] = 1 # delete $x->[0]->[1] # '', 1, [ [ ] ] # +delete
+$x->[0]->[1] = 1 # delete $x->[0]->[3] # '', undef, [ [ undef, 1 ] ]# +delete
+$x->[0]->[1] = 1 # delete $x->[2]->[3] # '', undef, [ [ undef, 1 ] ]# +delete
+$x->[0]->[1] = 1 # delete $x->[0]->[1] # '', 1, [ [ ] ] # +store
+$x->[0]->[1] = 1 # delete $x->[0]->[3] # '', undef, [ [ undef, 1 ] ]# +store
+$x->[0]->[1] = 1 # delete $x->[2]->[3] # '', undef, [ [ undef, 1 ], undef, [ ] ] # +store
+
+$x->[0]->[1] = 1 # delete $x->[0]->[1] # '', 1, [ [ ] ] # +strict +fetch
+$x->[0]->[1] = 1 # delete $x->[0]->[3] # '', undef, [ [ undef, 1 ] ] # +strict +fetch
+$x->[0]->[1] = 1 # delete $x->[2]->[3] # '', undef, [ [ undef, 1 ], undef, [ ] ]# +strict +fetch
+$x->[0]->[1] = 1 # delete $x->[0]->[1] # '', 1, [ [ ] ] # +strict +exists
+$x->[0]->[1] = 1 # delete $x->[0]->[3] # '', undef, [ [ undef, 1 ] ] # +strict +exists
+$x->[0]->[1] = 1 # delete $x->[2]->[3] # '', undef, [ [ undef, 1 ], undef, [ ] ]# +strict +exists
+$x->[0]->[1] = 1 # delete $x->[0]->[1] # '', 1, [ [ ] ] # +strict +delete
+$x->[0]->[1] = 1 # delete $x->[0]->[3] # '', undef, [ [ undef, 1 ] ] # +strict +delete
+$x->[0]->[1] = 1 # delete $x->[2]->[3] # qr/^Reference vivification forbidden/, undef, [ [ undef, 1 ] ] # +strict +delete
+$x->[0]->[1] = 1 # delete $x->[0]->[1] # '', 1, [ [ ] ] # +strict +store
+$x->[0]->[1] = 1 # delete $x->[0]->[3] # '', undef, [ [ undef, 1 ] ] # +strict +store
+$x->[0]->[1] = 1 # delete $x->[2]->[3] # '', undef, [ [ undef, 1 ], undef, [ ] ]# +strict +store
+
+--- store ---
+
+$x # $x->[0] = 1 # '', 1, [ 1 ]
+$x # $x->[0] = 1 # '', 1, [ 1 ] #
+$x # $x->[0] = 1 # '', 1, [ 1 ] # +fetch
+$x # $x->[0] = 1 # '', 1, [ 1 ] # +exists
+$x # $x->[0] = 1 # '', 1, [ 1 ] # +delete
+$x # $x->[0] = 1 # qr/^Can't vivify reference/, undef, undef # +store
+
+$x # $x->[0] = 1 # '', 1, [ 1 ] # +strict +fetch
+$x # $x->[0] = 1 # '', 1, [ 1 ] # +strict +exists
+$x # $x->[0] = 1 # '', 1, [ 1 ] # +strict +delete
+$x # $x->[0] = 1 # qr/^Reference vivification forbidden/, undef, undef # +strict +store
+
+$x # $x->[0]->[1] = 1 # '', 1, [ [ undef, 1 ] ]
+$x # $x->[0]->[1] = 1 # '', 1, [ [ undef, 1 ] ] #
+$x # $x->[0]->[1] = 1 # '', 1, [ [ undef, 1 ] ] # +fetch
+$x # $x->[0]->[1] = 1 # '', 1, [ [ undef, 1 ] ] # +exists
+$x # $x->[0]->[1] = 1 # '', 1, [ [ undef, 1 ] ] # +delete
+$x # $x->[0]->[1] = 1 # qr/^Can't vivify reference/, undef, undef # +store
+
+$x # $x->[0]->[1] = 1 # '', 1, [ [ undef, 1 ] ] # +strict +fetch
+$x # $x->[0]->[1] = 1 # '', 1, [ [ undef, 1 ] ] # +strict +exists
+$x # $x->[0]->[1] = 1 # '', 1, [ [ undef, 1 ] ] # +strict +delete
+$x # $x->[0]->[1] = 1 # qr/^Reference vivification forbidden/, undef, undef # +strict +store
+
+$x->[0] = 1 # $x->[0] = 2 # '', 2, [ 2 ] # +fetch
+$x->[0] = 1 # $x->[1] = 2 # '', 2, [ 1, 2 ] # +fetch
+$x->[0] = 1 # $x->[0] = 2 # '', 2, [ 2 ] # +exists
+$x->[0] = 1 # $x->[1] = 2 # '', 2, [ 1, 2 ] # +exists
+$x->[0] = 1 # $x->[0] = 2 # '', 2, [ 2 ] # +delete
+$x->[0] = 1 # $x->[1] = 2 # '', 2, [ 1, 2 ] # +delete
+$x->[0] = 1 # $x->[0] = 2 # '', 2, [ 2 ] # +store
+$x->[0] = 1 # $x->[1] = 2 # '', 2, [ 1, 2 ] # +store
+
+$x->[0] = 1 # $x->[0] = 2 # '', 2, [ 2 ] # +strict +fetch
+$x->[0] = 1 # $x->[1] = 2 # '', 2, [ 1, 2 ] # +strict +fetch
+$x->[0] = 1 # $x->[0] = 2 # '', 2, [ 2 ] # +strict +exists
+$x->[0] = 1 # $x->[1] = 2 # '', 2, [ 1, 2 ] # +strict +exists
+$x->[0] = 1 # $x->[0] = 2 # '', 2, [ 2 ] # +strict +delete
+$x->[0] = 1 # $x->[1] = 2 # '', 2, [ 1, 2 ] # +strict +delete
+$x->[0] = 1 # $x->[0] = 2 # '', 2, [ 2 ] # +strict +store
+$x->[0] = 1 # $x->[1] = 2 # '', 2, [ 1, 2 ] # +strict +store
+
+$x->[0]->[1] = 1 # $x->[0]->[1] = 2 # '', 2, [ [ undef, 2 ] ] # +fetch
+$x->[0]->[1] = 1 # $x->[0]->[3] = 2 # '', 2, [ [ undef, 1, undef, 2 ] ] # +fetch
+$x->[0]->[1] = 1 # $x->[2]->[3] = 2 # '', 2, [ [ undef, 1 ], undef, [ undef, undef, undef, 2 ] ] # +fetch
+$x->[0]->[1] = 1 # $x->[0]->[1] = 2 # '', 2, [ [ undef, 2 ] ] # +exists
+$x->[0]->[1] = 1 # $x->[0]->[3] = 2 # '', 2, [ [ undef, 1, undef, 2 ] ] # +exists
+$x->[0]->[1] = 1 # $x->[2]->[3] = 2 # '', 2, [ [ undef, 1 ], undef, [ undef, undef, undef, 2 ] ] # +exists
+$x->[0]->[1] = 1 # $x->[0]->[1] = 2 # '', 2, [ [ undef, 2 ] ] # +delete
+$x->[0]->[1] = 1 # $x->[0]->[3] = 2 # '', 2, [ [ undef, 1, undef, 2 ] ] # +delete
+$x->[0]->[1] = 1 # $x->[2]->[3] = 2 # '', 2, [ [ undef, 1 ], undef, [ undef, undef, undef, 2 ] ] # +delete
+$x->[0]->[1] = 1 # $x->[0]->[1] = 2 # '', 2, [ [ undef, 2 ] ] # +store
+$x->[0]->[1] = 1 # $x->[0]->[3] = 2 # '', 2, [ [ undef, 1, undef, 2 ] ] # +store
+$x->[0]->[1] = 1 # $x->[2]->[3] = 2 # qr/^Can't vivify reference/, undef, [ [ undef, 1 ] ] # +store
+
+$x->[0]->[1] = 1 # $x->[0]->[1] = 2 # '', 2, [ [ undef, 2 ] ] # +strict +fetch
+$x->[0]->[1] = 1 # $x->[0]->[3] = 2 # '', 2, [ [ undef, 1, undef, 2 ] ] # +strict +fetch
+$x->[0]->[1] = 1 # $x->[2]->[3] = 2 # '', 2, [ [ undef, 1 ], undef, [ undef, undef, undef, 2 ] ] # +strict +fetch
+$x->[0]->[1] = 1 # $x->[0]->[1] = 2 # '', 2, [ [ undef, 2 ] ] # +strict +exists
+$x->[0]->[1] = 1 # $x->[0]->[3] = 2 # '', 2, [ [ undef, 1, undef, 2 ] ] # +strict +exists
+$x->[0]->[1] = 1 # $x->[2]->[3] = 2 # '', 2, [ [ undef, 1 ], undef, [ undef, undef, undef, 2 ] ] # +strict +exists
+$x->[0]->[1] = 1 # $x->[0]->[1] = 2 # '', 2, [ [ undef, 2 ] ] # +strict +delete
+$x->[0]->[1] = 1 # $x->[0]->[3] = 2 # '', 2, [ [ undef, 1, undef, 2 ] ] # +strict +delete
+$x->[0]->[1] = 1 # $x->[2]->[3] = 2 # '', 2, [ [ undef, 1 ], undef, [ undef, undef, undef, 2 ] ] # +strict +delete
+$x->[0]->[1] = 1 # $x->[0]->[1] = 2 # '', 2, [ [ undef, 2 ] ] # +strict +store
+$x->[0]->[1] = 1 # $x->[0]->[3] = 2 # '', 2, [ [ undef, 1, undef, 2 ] ] # +strict +store
+$x->[0]->[1] = 1 # $x->[2]->[3] = 2 # qr/^Reference vivification forbidden/, undef, [ [ undef, 1 ] ] # +strict +store