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#!./perl -w
# tests state variables
BEGIN {
chdir 't' if -d 't';
require './test.pl';
set_up_inc('../lib');
}
use strict;
plan tests => 170;
# Before loading feature.pm, test it with CORE::
ok eval 'CORE::state $x = 1;', 'CORE::state outside of feature.pm scope';
use feature ":5.10";
ok( ! defined state $uninit, q(state vars are undef by default) );
# basic functionality
sub stateful {
state $x;
state $y = 1;
my $z = 2;
state ($t) //= 3;
return ($x++, $y++, $z++, $t++);
}
my ($x, $y, $z, $t) = stateful();
is( $x, 0, 'uninitialized state var' );
is( $y, 1, 'initialized state var' );
is( $z, 2, 'lexical' );
is( $t, 3, 'initialized state var, list syntax' );
($x, $y, $z, $t) = stateful();
is( $x, 1, 'incremented state var' );
is( $y, 2, 'incremented state var' );
is( $z, 2, 'reinitialized lexical' );
is( $t, 4, 'incremented state var, list syntax' );
($x, $y, $z, $t) = stateful();
is( $x, 2, 'incremented state var' );
is( $y, 3, 'incremented state var' );
is( $z, 2, 'reinitialized lexical' );
is( $t, 5, 'incremented state var, list syntax' );
# in a nested block
sub nesting {
state $foo = 10;
my $t;
{ state $bar = 12; $t = ++$bar }
++$foo;
return ($foo, $t);
}
($x, $y) = nesting();
is( $x, 11, 'outer state var' );
is( $y, 13, 'inner state var' );
($x, $y) = nesting();
is( $x, 12, 'outer state var' );
is( $y, 14, 'inner state var' );
# in a closure
sub generator {
my $outer;
# we use $outer to generate a closure
sub { ++$outer; ++state $x }
}
my $f1 = generator();
is( $f1->(), 1, 'generator 1' );
is( $f1->(), 2, 'generator 1' );
my $f2 = generator();
is( $f2->(), 1, 'generator 2' );
is( $f1->(), 3, 'generator 1 again' );
is( $f2->(), 2, 'generator 2 once more' );
# with ties
{
package countfetches;
our $fetchcount = 0;
sub TIESCALAR {bless {}};
sub FETCH { ++$fetchcount; 18 };
tie my $y, "countfetches";
sub foo { state $x = $y; $x++ }
::is( foo(), 18, "initialisation with tied variable" );
::is( foo(), 19, "increments correctly" );
::is( foo(), 20, "increments correctly, twice" );
::is( $fetchcount, 1, "fetch only called once" );
}
# state variables are shared among closures
sub gen_cashier {
my $amount = shift;
state $cash_in_store = 0;
return {
add => sub { $cash_in_store += $amount },
del => sub { $cash_in_store -= $amount },
bal => sub { $cash_in_store },
};
}
gen_cashier(59)->{add}->();
gen_cashier(17)->{del}->();
is( gen_cashier()->{bal}->(), 42, '$42 in my drawer' );
# stateless assignment to a state variable
sub stateless {
state $reinitme = 42;
++$reinitme;
}
is( stateless(), 43, 'stateless function, first time' );
is( stateless(), 44, 'stateless function, second time' );
# array state vars
sub stateful_array {
state @x;
push @x, 'x';
return $#x;
}
my $xsize = stateful_array();
is( $xsize, 0, 'uninitialized state array' );
$xsize = stateful_array();
is( $xsize, 1, 'uninitialized state array after one iteration' );
sub stateful_init_array {
state @x = qw(a b c);
push @x, "x";
return join(",", @x);
}
is stateful_init_array(), "a,b,c,x";
is stateful_init_array(), "a,b,c,x,x";
is stateful_init_array(), "a,b,c,x,x,x";
# hash state vars
sub stateful_hash {
state %hx;
return $hx{foo}++;
}
my $xhval = stateful_hash();
is( $xhval, 0, 'uninitialized state hash' );
$xhval = stateful_hash();
is( $xhval, 1, 'uninitialized state hash after one iteration' );
sub stateful_init_hash {
state %x = qw(a b c d);
$x{foo}++;
return join(",", map { ($_, $x{$_}) } sort keys %x);
}
is stateful_init_hash(), "a,b,c,d,foo,1";
is stateful_init_hash(), "a,b,c,d,foo,2";
is stateful_init_hash(), "a,b,c,d,foo,3";
# declarations with attributes
SKIP: {
skip "no attributes in miniperl", 3, if is_miniperl;
eval q{
sub stateful_attr {
state $a :shared;
state $b :shared = 3;
state @c :shared;
state @d :shared = qw(a b c);
state %e :shared;
state %f :shared = qw(a b c d);
$a++;
$b++;
push @c, "x";
push @d, "x";
$e{e}++;
$f{e}++;
return join(",", $a, $b, join(":", @c), join(":", @d), join(":", %e),
join(":", map { ($_, $f{$_}) } sort keys %f));
}
};
is stateful_attr(), "1,4,x,a:b:c:x,e:1,a:b:c:d:e:1";
is stateful_attr(), "2,5,x:x,a:b:c:x:x,e:2,a:b:c:d:e:2";
is stateful_attr(), "3,6,x:x:x,a:b:c:x:x:x,e:3,a:b:c:d:e:3";
}
# Recursion
sub noseworth {
my $level = shift;
state $recursed_state = 123;
is($recursed_state, 123, "state kept through recursion ($level)");
noseworth($level - 1) if $level;
}
noseworth(2);
# Assignment return value
sub pugnax { my $x = state $y = 42; $y++; $x; }
is( pugnax(), 42, 'scalar state assignment return value' );
is( pugnax(), 43, 'scalar state assignment return value' );
#
# Test various blocks.
#
foreach my $x (1 .. 3) {
state $y = $x;
is ($y, 1, "foreach $x");
}
for (my $x = 1; $x < 4; $x ++) {
state $y = $x;
is ($y, 1, "for $x");
}
while ($x < 4) {
state $y = $x;
is ($y, 1, "while $x");
$x ++;
}
$x = 1;
until ($x >= 4) {
state $y = $x;
is ($y, 1, "until $x");
$x ++;
}
$x = 0;
$y = 0;
{
state $z = $x;
$z ++;
$y ++;
is ($z, $y, "bare block $y");
redo if $y < 3
}
#
# Goto.
#
my @simpsons = qw [Homer Marge Bart Lisa Maggie];
again:
my $next = shift @simpsons;
state $simpson = $next;
is $simpson, 'Homer', 'goto 1';
goto again if @simpsons;
my $vi;
{
goto Elvis unless $vi;
state $calvin = ++ $vi;
Elvis: state $vile = ++ $vi;
redo unless defined $calvin;
is $calvin, 2, "goto 2";
is $vile, 1, "goto 3";
is $vi, 2, "goto 4";
}
my @presidents = qw [Taylor Garfield Ford Arthur Monroe];
sub president {
my $next = shift @presidents;
state $president = $next;
goto &president if @presidents;
$president;
}
my $president_answer = $presidents [0];
is president, $president_answer, '&goto';
my @flowers = qw [Bluebonnet Goldenrod Hawthorn Peony];
foreach my $f (@flowers) {
goto state $flower = $f;
ok 0, 'computed goto 0'; next;
Bluebonnet: ok 1, 'computed goto 1'; next;
Goldenrod: ok 0, 'computed goto 2'; next;
Hawthorn: ok 0, 'computed goto 3'; next;
Peony: ok 0, 'computed goto 4'; next;
ok 0, 'computed goto 5'; next;
}
#
# map/grep
#
my @apollo = qw [Eagle Antares Odyssey Aquarius];
my @result1 = map {state $x = $_;} @apollo;
my @result2 = grep {state $x = /Eagle/} @apollo;
{
local $" = "";
is "@result1", $apollo [0] x @apollo, "map";
is "@result2", "@apollo", "grep";
}
#
# Reference to state variable.
#
sub reference {\state $x}
my $ref1 = reference;
my $ref2 = reference;
is $ref1, $ref2, "Reference to state variable";
#
# Pre/post increment.
#
foreach my $x (1 .. 3) {
++ state $y;
state $z ++;
is $y, $x, "state pre increment";
is $z, $x, "state post increment";
}
#
# Substr
#
my $tintin = "Tin-Tin";
my @thunderbirds = qw [Scott Virgel Alan Gordon John];
my @thunderbirds2 = qw [xcott xxott xxxtt xxxxt xxxxx];
foreach my $x (0 .. 4) {
state $c = \substr $tintin, $x, 1;
my $d = \substr ((state $tb = $thunderbirds [$x]), $x, 1);
$$c = "x";
$$d = "x";
is $tintin, "xin-Tin", "substr";
is $tb, $thunderbirds2 [$x], "substr";
}
#
# Use with given.
#
my @spam = qw [spam ham bacon beans];
foreach my $spam (@spam) {
no warnings 'deprecated';
given (state $spam = $spam) {
when ($spam [0]) {ok 1, "given"}
default {ok 0, "given"}
}
}
#
# Redefine.
#
{
state $x = "one";
no warnings;
state $x = "two";
is $x, "two", "masked"
}
# normally closureless anon subs share a CV and pad. If the anon sub has a
# state var, this would mean that it is shared. Check that this doesn't
# happen
{
my @f;
push @f, sub { state $x; ++$x } for 1..2;
$f[0]->() for 1..10;
is $f[0]->(), 11;
is $f[1]->(), 1;
}
# each copy of an anon sub should get its own 'once block'
{
my $x; # used to force a closure
my @f;
push @f, sub { $x=0; state $s = $_[0]; $s } for 1..2;
is $f[0]->(1), 1;
is $f[0]->(2), 1;
is $f[1]->(3), 3;
is $f[1]->(4), 3;
}
foreach my $forbidden (<DATA>) {
SKIP: {
skip_if_miniperl("miniperl can't load attributes.pm", 1)
if $forbidden =~ /:shared/;
chomp $forbidden;
no strict 'vars';
eval $forbidden;
like $@,
qr/Initialization of state variables in list currently forbidden/,
"Currently forbidden: $forbidden";
}
}
# [perl #49522] state variable not available
{
my @warnings;
local $SIG{__WARN__} = sub { push @warnings, $_[0] };
eval q{
use warnings;
sub f_49522 {
state $s = 88;
sub g_49522 { $s }
sub { $s };
}
sub h_49522 {
state $t = 99;
sub i_49522 {
sub { $t };
}
}
};
is $@, '', "eval f_49522";
# shouldn't be any 'not available' or 'not stay shared' warnings
ok !@warnings, "suppress warnings part 1 [@warnings]";
@warnings = ();
my $f = f_49522();
is $f->(), 88, "state var closure 1";
is g_49522(), 88, "state var closure 2";
ok !@warnings, "suppress warnings part 2 [@warnings]";
@warnings = ();
$f = i_49522();
h_49522(); # initialise $t
is $f->(), 99, "state var closure 3";
ok !@warnings, "suppress warnings part 3 [@warnings]";
}
# [perl #117095] state var initialisation getting skipped
# the 'if 0' code below causes a call to op_free at compile-time,
# which used to inadvertently mark the state var as initialised.
{
state $f = 1;
foo($f) if 0; # this calls op_free on padmy($f)
ok(defined $f, 'state init not skipped');
}
# [perl #121134] Make sure padrange doesn't mess with these
{
sub thing {
my $expect = shift;
my ($x, $y);
state $z;
is($z, $expect, "State variable is correct");
$z = 5;
}
thing(undef);
thing(5);
sub thing2 {
my $expect = shift;
my $x;
my $y;
state $z;
is($z, $expect, "State variable is correct");
$z = 6;
}
thing2(undef);
thing2(6);
}
# [perl #123029] regression in "state" under PERL_NO_COW
sub rt_123029 {
state $s;
$s = 'foo'x500;
my $c = $s;
return defined $s;
}
ok(rt_123029(), "state variables don't surprisingly disappear when accessed");
# make sure multiconcat doesn't break state
for (1,2) {
state $s = "-$_-";
is($s, "-1-", "state with multiconcat pass $_");
}
# This caused 'Attempt to free unreferenced scalar' because the SV holding
# the value of the const state sub wasn't having its ref count incremented
# when the sub was cloned.
{
my @warnings;
local $SIG{__WARN__} = sub { push @warnings, @_ };
my $e = eval 'my $s = sub { state sub FOO () { 42 } }; 1;';
is($e, 1, "const state sub ran ok");
ok(!@warnings, "no 'Attempt to free unreferenced scalar'")
or diag "got these warnings:\n@warnings";
}
# [GH #18630] Returning state hash-assign risks "Bizarre copy of HASH in subroutine exit"
{
sub gh_18630H {state %h=(a=>1)}
my $res = join '', gh_18630H, gh_18630H;
is($res, "a1a1", 'HASH copied successfully in subroutine exit');
is(scalar gh_18630H, 1, 'gh_18630H scalar call returns key count');
sub gh_18630A {state @a = qw(b 2)}
$res = join '', gh_18630A , gh_18630A;
is($res, "b2b2", 'ARRAY copied successfully in subroutine exit');
is(scalar gh_18630A, 2, 'gh_18630A scalar call returns element count');
}
__DATA__
(state $a) = 1;
(state @a) = 1;
(state @a :shared) = 1;
(state %a) = ();
(state %a :shared) = ();
state ($a) = 1;
(state ($a)) = 1;
state (@a) = 1;
(state (@a)) = 1;
state (@a) :shared = 1;
(state (@a) :shared) = 1;
state (%a) = ();
(state (%a)) = ();
state (%a) :shared = ();
(state (%a) :shared) = ();
state (undef, $a) = ();
(state (undef, $a)) = ();
state (undef, @a) = ();
(state (undef, @a)) = ();
state ($a, undef) = ();
(state ($a, undef)) = ();
state ($a, $b) = ();
(state ($a, $b)) = ();
state ($a, $b) :shared = ();
(state ($a, $b) :shared) = ();
state ($a, @b) = ();
(state ($a, @b)) = ();
state ($a, @b) :shared = ();
(state ($a, @b) :shared) = ();
state (@a, undef) = ();
(state (@a, undef)) = ();
state (@a, $b) = ();
(state (@a, $b)) = ();
state (@a, $b) :shared = ();
(state (@a, $b) :shared) = ();
state (@a, @b) = ();
(state (@a, @b)) = ();
state (@a, @b) :shared = ();
(state (@a, @b) :shared) = ();
(state $a, state $b) = ();
(state $a, $b) = ();
(state $a, my $b) = ();
(state $a, state @b) = ();
(state $a, local @b) = ();
(state $a, undef, state $b) = ();
state ($a, undef, $b) = ();