Some errors for auto_deref

[gitmo/Mouse.git] / lib / Mouse.pm

diff --git a/lib/Mouse.pm b/lib/Mouse.pm
index dae207d..58637af 100644 (file)
--- a/lib/Mouse.pm
+++ b/lib/Mouse.pm
@@ -83,6 +83,11 @@ do {
 sub load_class {
     my $class = shift;
 
+    if (ref($class) || !defined($class) || !length($class)) {
+        my $display = defined($class) ? $class : 'undef';
+        confess "Invalid class name ($display)";
+    }
+
     return 1 if is_class_loaded($class);
 
     (my $file = "$class.pm") =~ s{::}{/}g;
@@ -96,12 +101,30 @@ sub load_class {
 sub is_class_loaded {
     my $class = shift;
 
-    no strict 'refs';
-    return 1 if defined ${"${class}::VERSION"} || defined @{"${class}::ISA"};
-    foreach my $symbol (keys %{"${class}::"}) {
-            next if substr($symbol, -2, 2) eq '::';
-            return 1 if defined &{"${class}::${symbol}"};
+    return 0 if ref($class) || !defined($class) || !length($class);
+
+    # walk the symbol table tree to avoid autovififying
+    # \*{${main::}{"Foo::"}} == \*main::Foo::
+
+    my $pack = \*::;
+    foreach my $part (split('::', $class)) {
+        return 0 unless exists ${$$pack}{"${part}::"};
+        $pack = \*{${$$pack}{"${part}::"}};
+    }
+
+    # check for $VERSION or @ISA
+    return 1 if exists ${$$pack}{VERSION}
+             && defined *{${$$pack}{VERSION}}{SCALAR};
+    return 1 if exists ${$$pack}{ISA}
+             && defined *{${$$pack}{ISA}}{ARRAY};
+
+    # check for any method
+    foreach ( keys %{$$pack} ) {
+        next if substr($_, -2, 2) eq '::';
+        return 1 if defined *{${$$pack}{$_}}{CODE};
     }
+
+    # fail
     return 0;
 }
 
@@ -190,6 +213,12 @@ This will load a given C<Class::Name> (or die if it's not loadable).
 This function can be used in place of tricks like
 C<eval "use $module"> or using C<require>.
 
+=head2 is_class_loaded Class::Name -> Bool
+
+Returns whether this class is actually loaded or not. It uses a heuristic which
+involves checking for the existence of C<$VERSION>, C<@ISA>, and any
+locally-defined method.
+
 =head1 AUTHOR
 
 Shawn M Moore, C<< <sartak at gmail.com> >>