Implement $ua->is_online test

Inspired by LWP::Online

MANIFEST

@@ -39,6 +39,7 @@ t/TEST				Run tests
 t/base/protocols.t		Test protocol methods of LWP::UserAgent
 t/base/ua.t			Basic LWP::UserAgent tests
 t/live/apache-http10.t
+t/live/online.t
 t/live/jigsaw-auth-b.t
 t/live/jigsaw-auth-d.t
 t/live/jigsaw-chunk.t

lib/LWP/UserAgent.pm

@@ -476,6 +476,15 @@ sub _process_colonic_headers {
     return $arg;
 }
 
+
+sub is_online {
+    my $self = shift;
+    return 1 if $self->get("http://www.msftncsi.com/ncsi.txt")->content eq "Microsoft NCSI";
+    return 1 if $self->get("http://www.apple.com")->content =~ m,<title>Apple</title>,;
+    return 0;
+}
+
+
 my @ANI = qw(- \ | /);
 
 sub progress {
@@ -1700,6 +1709,12 @@ The difference from request() is that simple_request() will not try to
 handle redirects or authentication responses.  The request() method
 will in fact invoke this method for each simple request it sends.
 
+=item $ua->is_online
+
+Tries to determine if you have access to the Internet.  Returns
+TRUE if the built-in heuristics determine that the user agent is
+able to access the Internet (over HTTP).  See also L<LWP::Online>.
+
 =item $ua->is_protocol_supported( $scheme )
 
 You can use this method to test whether this user agent object supports the

t/live/online.t

@@ -0,0 +1,13 @@
+#!perl -w
+
+use strict;
+use Test;
+plan tests => 2;
+
+use LWP::UserAgent;
+my $ua = LWP::UserAgent->new;
+
+ok $ua->is_online;
+
+$ua->protocols_allowed([]);
+ok !$ua->is_online;