API.pm: undef query parameters should not be considered "extra"

GitLab/API.pm

@@ -162,7 +162,7 @@ sub create_uri {
 
     # add query parameters
     foreach my $param (@{$tmpl->{query} // []}) {
-        if (defined $args->{$param}) {
+        if (exists $args->{$param}) {
             $uri->query_param($param => $args->{$param});
             delete $args->{$param};
         }
@@ -201,10 +201,18 @@ sub exec_request {
     delete @{$args}{@rtkeys};
 
     if ($log->is_debug) {
-        my $argstr = join ", ", map { "$_ => " . ($_ eq "password" ? "<redacted>" : "\"$args->{$_}\"") } (keys %$args);
-        my $rtstr  = join ", ", map { "$_ => $rtargs->{$_}" } (@rtkeys);
-        $log->debug("called GitLab::API::$tmpl->{name}($argstr)");
-        $log->debug("request options: [$rtstr]");
+        my @bits;
+
+        for my $key (keys %$args) {
+            my $value = $key eq "password"      ? "<redacted>"
+                      : !defined $args->{$key}  ? "<undef>"
+                      : "\"$args->{$key}\"";
+
+            push @bits, "$key => $value";
+        }
+
+        push @bits, "[$_ => $rtargs->{$_}]" foreach @rtkeys;
+        $log->debug("called GitLab::API::$tmpl->{name}(" . (join ", ", @bits) . ")");
     }
 
     my $uri = $self->create_uri($tmpl, $args);