fix undef warning in Mojo::JSON::Pointer when fragment is undef

Use of uninitialized value $pointer in substitution (s///) at .../Mojo/JSON/Pointer.pm line 15.

Author: karenetheridge

Changes

@@ -1,6 +1,7 @@
 Revision history for JSON-Schema-Tiny
 
 {{$NEXT}}
+         - fix warning when using a $ref to a URI with no fragment
 
 0.018     2022-08-06 22:02:20Z
          - update test skip list for latest release of the test suite

lib/JSON/Schema/Tiny.pm

@@ -259,7 +259,7 @@ sub _eval_keyword_ref ($data, $schema, $state) {
   abort($state, 'only same-document, same-base JSON pointers are supported in %s', $state->{keyword})
     if $uri->clone->fragment(undef) ne Mojo::URL->new($state->{root_schema}{'$id'}//'');
 
-  my $subschema = Mojo::JSON::Pointer->new($state->{root_schema})->get($uri->fragment);
+  my $subschema = Mojo::JSON::Pointer->new($state->{root_schema})->get($uri->fragment//'');
   abort($state, 'EXCEPTION: unable to find resource %s', $uri) if not defined $subschema;
 
   return _eval_subschema($data, $subschema,

t/ref.t

@@ -71,4 +71,34 @@ subtest 'local anchor' => sub {
   fail;
 };
 
+subtest '$ref using the local $id' => sub {
+  cmp_deeply(
+    evaluate(
+      1,
+      {
+        '$id' => 'https://localhost:1234/blah',
+        '$defs' => { 'my-definition' => true },
+        '$ref' => 'https://localhost:1234/blah#/$defs/my-definition',
+      },
+    ),
+    { valid => true },
+    'can follow $ref using a base URI that matches our document',
+  );
+
+  cmp_deeply(
+    evaluate(
+      [ 'foo', [ 'bar' ] ],
+      {
+        '$id' => 'https://localhost:1234/blah',
+        anyOf => [
+          { type => 'string' },
+          { type => 'array', items => { '$ref' => 'https://localhost:1234/blah' } },
+        ],
+      },
+    ),
+    { valid => true },
+    'can follow $ref using a base URI that matches our document',
+  );
+};
+
 done_testing;