deduplicate outputs of perlbrew list when PATH contain duplicated i…

…tems.

lib/App/perlbrew.pm

@@ -223,8 +223,7 @@ sub uniq(@) {
             if $command[0] eq 'wget' # Exit code is 8 on 404s etc
             and $? >> 8 == 8;
 
-        $cb ||= sub { return $_[0] };
-        return $cb->($body);
+        return $cb ? $cb->($body) : $body;
     }
 }
 
@@ -839,7 +838,7 @@ sub installed_perls {
     $current_perl_executable =~ s/\n$//;
 
     my $current_perl_executable_version;
-    for ( uniq grep { -f $_ && -x $_ } map { "$_/perl" } split(":", $self->env('PATH')) ) {
+    for ( grep { -f $_ && -x $_ } uniq map { s/\/+$//; "$_/perl" } split(":", $self->env('PATH')) ) {
         $current_perl_executable_version =
           $self->format_perl_version(`$_ -e 'print \$]'`);
         push @result, {

perlbrew

@@ -585,9 +585,13 @@ sub do_install_blead {
     print "Fetching $dist_git_describe as $dist_tarball_path\n";
     http_get(
         "http://perl5.git.perl.org/perl.git/snapshot/$dist_tarball",
-        undef,
         sub {
             my ($body) = @_;
+
+            unless ($body) {
+                die "\nERROR: Failed to download perl-blead tarball.\n\n";
+            }
+
             open my $BALL, "> $dist_tarball_path" or die "Couldn't open $dist_tarball_path: $!";
             print $BALL $body;
             close $BALL;
@@ -623,6 +627,10 @@ sub do_install_release {
     my $header = $mirror ? { 'Cookie' => "cpan=$mirror->{url}" } : undef;
     my $html = http_get("http://search.cpan.org/dist/$dist", $header);
 
+    unless ($html) {
+        die "ERROR: Failed to download $dist tarball.";
+    }
+
     my ($dist_path, $dist_tarball) =
         $html =~ m[<a href="(/CPAN/authors/id/.+/(${dist}.tar.(gz|bz2)))">Download</a>];
     die "ERROR: Cannot find the tarball for $dist\n"
@@ -832,7 +840,7 @@ sub installed_perls {
     $current_perl_executable =~ s/\n$//;
 
     my $current_perl_executable_version;
-    for ( uniq grep { -f $_ && -x $_ } map { "$_/perl" } split(":", $self->env('PATH')) ) {
+    for ( grep { -f $_ && -x $_ } uniq map { s/\/+$//; "$_/perl" } split(":", $self->env('PATH')) ) {
         $current_perl_executable_version =
           $self->format_perl_version(`$_ -e 'print \$]'`);
         push @result, {