1 files changed, 59 insertions, 0 deletions
diff --git a/t/06_invocant.t b/t/06_invocant.t
new file mode 100644
index 0000000..2722c63
--- /dev/null
+++ b/t/06_invocant.t
@@ -0,0 +1,59 @@
+#!/usr/bin/perl
+
+use strict;
+BEGIN {
+	$|  = 1;
+	$^W = 1;
+	$ENV{PERL_PARAMS_UTIL_PP} ||= 0;
+}
+
+use Test::More tests => 11;
+use File::Spec::Functions ':ALL';
+BEGIN {
+	use_ok('Params::Util', qw(_INVOCANT));
+}
+
+my $object = bless \do { my $i } => 'Params::Util::Test::Bogus::Whatever';
+my $false_obj1 = bless \do { my $i } => 0;
+my $false_obj2 = bless \do { my $i } => "\0";
+my $tied   = tie my $x, 'Params::Util::Test::_INVOCANT::Tied';
+my $unpkg  = 'Params::Util::Test::_INVOCANT::Fake';
+my $pkg    = 'Params::Util::Test::_INVOCANT::Real'; eval "package $pkg;"; ## no critic
+
+my @data = (# I
+  [ undef        , 0, 'undef' ],
+  [ 1000        => 0, '1000' ],
+  [ $unpkg      => 1, qq("$unpkg") ],
+  [ $pkg        => 1, qq("$pkg") ],
+  [ []          => 0, '[]' ],
+  [ {}          => 0, '{}' ],
+  [ $object     => 1, 'blessed reference' ],
+  [ $false_obj1 => 1, 'blessed reference' ],
+  [ $tied       => 1, 'tied value' ],
+);
+
+for my $datum (@data) {
+  is(
+    _INVOCANT($datum->[0]) ? 1 : 0,
+    $datum->[1],
+    "$datum->[2] " . ($datum->[1] ? 'is' : "isn't") . " _IN"
+  );
+}
+
+# Skip the most evil test except on automated testing, because it
+# fails on at least one common production OS (RedHat Enterprise Linux 4)
+# and the test case should be practically impossible to encounter
+# in real life. The damage the bug could cause users in production is
+# far lower than the damage caused by Params::Util failing to install.
+SKIP: {
+	unless ( $ENV{AUTOMATED_TESTING} ) {
+		skip("Skipping nasty test unless AUTOMATED_TESTING", 1);
+	}
+	ok( !! _INVOCANT($false_obj2), 'Testing null class as an invocant' );
+}
+
+package Params::Util::Test::_INVOCANT::Tied;
+sub TIESCALAR {
+  my ($class, $value) = @_;
+  return bless \$value => $class;
+}