+package Variable::Magic::TestThreads;
+
+use strict;
+use warnings;
+
+use Config qw<%Config>;
+
+use Variable::Magic qw<VMG_THREADSAFE>;
+
+sub skipall {
+ my ($msg) = @_;
+ require Test::More;
+ Test::More::plan(skip_all => $msg);
+}
+
+sub diag {
+ require Test::More;
+ Test::More::diag(@_);
+}
+
+sub import {
+ shift;
+
+ skipall 'This Variable::Magic isn\'t thread safe' unless VMG_THREADSAFE;
+
+ my $force = $ENV{PERL_VARIABLE_MAGIC_TEST_THREADS} ? 1 : !1;
+ skipall 'This perl wasn\'t built to support threads'
+ unless $Config{useithreads};
+ skipall 'perl 5.13.4 required to test thread safety'
+ unless $force or "$]" >= 5.013004;
+
+ my $t_v = $force ? '0' : '1.67';
+ my $has_threads = do {
+ local $@;
+ eval "use threads $t_v; 1";
+ };
+ skipall "threads $t_v required to test thread safety" unless $has_threads;
+
+ my $ts_v = $force ? '0' : '1.14';
+ my $has_threads_shared = do {
+ local $@;
+ eval "use threads::shared $ts_v; 1";
+ };
+ skipall "threads::shared $ts_v required to test thread safety"
+ unless $has_threads_shared;
+
+ defined and diag "Using threads $_" for $threads::VERSION;
+ defined and diag "Using threads::shared $_" for $threads::shared::VERSION;
+
+ my %exports = (
+ spawn => \&spawn,
+ );
+
+ my $pkg = caller;
+ while (my ($name, $code) = each %exports) {
+ no strict 'refs';
+ *{$pkg.'::'.$name} = $code;
+ }
+}
+
+sub spawn {
+ local $@;
+ my @diag;
+ my $thread = eval {
+ local $SIG{__WARN__} = sub { push @diag, "Thread creation warning: @_" };
+ threads->create(@_);
+ };
+ push @diag, "Thread creation error: $@" if $@;
+ if (@diag) {
+ require Test::More;
+ Test::More::diag($_) for @diag;
+ }
+ return $thread ? $thread : ();
+}
+
+1;