fixed data race condition with loader options

loaders.go

@@ -4,6 +4,7 @@ import (
 	"encoding/json"
 	"errors"
 	"net/url"
+	"slices"
 
 	"github.com/go-openapi/spec"
 	"github.com/go-openapi/swag/loading"
@@ -107,6 +108,18 @@ func (l *loader) Load(path string) (json.RawMessage, error) {
 	return nil, errors.Join(lastErr, ErrLoads)
 }
 
+func (l *loader) clone() *loader {
+	if l == nil {
+		return nil
+	}
+
+	return &loader{
+		DocLoaderWithMatch: l.DocLoaderWithMatch,
+		loadingOptions:     slices.Clone(l.loadingOptions),
+		Next:               l.Next.clone(),
+	}
+}
+
 // JSONDoc loads a json document from either a file or a remote url.
 //
 // See [loading.Option] for available options (e.g. configuring authentifaction,

loaders_test.go

@@ -16,4 +16,8 @@ func TestLoader_EdgeCases(t *testing.T) {
 
 	_, err := ldr.Load(`d\::invalid uri\`)
 	require.Error(t, err)
+
+	clone := ldr.clone()
+	cnext := clone.WithHead(nil)
+	require.Equal(t, clone, cnext)
 }

options.go

@@ -19,7 +19,7 @@ func loaderFromOptions(options []LoaderOption) *loader {
 		apply(opts)
 	}
 
-	l := opts.loader
+	l := opts.loader.clone()
 	l.loadingOptions = opts.loadingOptions
 
 	return l