error when trying to init a stash slot with a value of the wrong type

2 files changed, 41 insertions, 0 deletions

diff --git a/lib/Stash/Manip.pm b/lib/Stash/Manip.pm
index 944eab3..40e9567 100644
--- a/lib/Stash/Manip.pm
+++ b/lib/Stash/Manip.pm
@@ -110,6 +110,19 @@ will create C<%Foo::foo>.
 
 =cut
 
+sub _valid_for_type {
+    my $self = shift;
+    my ($value, $type) = @_;
+    if ($type eq 'HASH' || $type eq 'ARRAY'
+     || $type eq 'IO'   || $type eq 'CODE') {
+        return reftype($value) eq $type;
+    }
+    else {
+        my $ref = reftype($value);
+        return !defined($ref) || $ref eq 'SCALAR' || $ref eq 'REF' || $ref eq 'LVALUE';
+    }
+}
+
 sub add_package_symbol {
     my ($self, $variable, $initial_value) = @_;
 
@@ -117,6 +130,11 @@ sub add_package_symbol {
         ? @{$variable}{qw[name sigil type]}
         : $self->_deconstruct_variable_name($variable);
 
+    if (@_ > 2) {
+        $self->_valid_for_type($initial_value, $type)
+            || confess "$initial_value is not of type $type";
+    }
+
     my $pkg = $self->name;
 
     no strict 'refs';
diff --git a/t/001-basic.t b/t/001-basic.t
index 52ddfaa..ef95bf1 100644
--- a/t/001-basic.t
+++ b/t/001-basic.t
@@ -225,4 +225,27 @@ is($foo_stash->get_package_symbol('@foo'), $ARRAY, '... got the right values for
     ok(defined(*{"Foo::foo"}{ARRAY}), '... the @foo slot has NOT been removed');
 }
 
+# check some errors
+
+dies_ok {
+    $foo_stash->add_package_symbol('@bar', {})
+} "can't initialize a slot with the wrong type of value";
+
+dies_ok {
+    $foo_stash->add_package_symbol('bar', [])
+} "can't initialize a slot with the wrong type of value";
+
+dies_ok {
+    $foo_stash->add_package_symbol('$bar', sub { })
+} "can't initialize a slot with the wrong type of value";
+
+{
+    package Bar;
+    open *foo, '<', $0;
+}
+
+dies_ok {
+    $foo_stash->add_package_symbol('$bar', *Bar::foo{IO})
+} "can't initialize a slot with the wrong type of value";
+
 done_testing;