Fix utf8 JSON configuration affecting tests

Changes

@@ -4,6 +4,7 @@ Revision history for Kelp
             [Changes]
             - Kelp::Exception->throw now also works on objects (rethrows an exception)
             - Fixed installed config method not returning the default value
+            - Fixed Kelp::Test being sensitive to utf8 configuration of the JSON encoder
             - Config module now allows overriding of the config merging routine
 
 2.11 - 2024-06-25

lib/Kelp/Test.pm

@@ -246,7 +246,9 @@ sub json_content
     fail "No JSON decoder" unless $self->app->can('json');
     my $result;
     try {
-        $result = $self->app->json->decode($self->res->content);
+        $result = $self->app->get_encoder(json => 'internal')->decode(
+            $self->_decode($self->res->content)
+        );
     }
     catch {
         fail("Poorly formatted JSON");

t/charset.t

@@ -84,5 +84,21 @@ subtest 'should set but not not override charset' => sub {
         ->content_is($text);
 };
 
+subtest 'should json_cmp UTF16 without problems with disabled utf8' => sub {
+    $t->charset('UTF-8');    # set charset for tests
+
+    $app->json->utf8(0);
+    $app->add_route(
+        '/false' => sub {
+            my $self = shift;
+            $self->res->charset('UTF-8');
+            return {false => 'fałsz'};
+        }
+    );
+
+    $t->request(GET '/false')
+        ->json_cmp({false => 'fałsz'});
+};
+
 done_testing;