fix: no content issues on error or pointer to Empty (#125)

Author: abemedia

handler.go

@@ -41,9 +41,10 @@ func H[T, O any](handle Handle[T, O]) httprouter.Handle {
 		var (
 			req = new(T)
 			res any
+			err error
 		)
 
-		err := decodeRequest(req, ctx, p)
+		err = decodeRequest(req, ctx, p)
 		if err != nil {
 			res = Error(err, getStatusCode(err, http.StatusBadRequest))
 		} else {
@@ -65,7 +66,7 @@ func H[T, O any](handle Handle[T, O]) httprouter.Handle {
 			ctx.SetStatusCode(sc.StatusCode())
 		}
 
-		if isNil(res) {
+		if err == nil && isNil(res) {
 			res = nil
 			ctx.Response.Header.SetContentLength(-3)
 		}

nilcheck.go

@@ -15,6 +15,9 @@ func makeNilCheck(zero any) func(v any) bool {
 	if _, ok := zero.(Empty); ok {
 		return func(v any) bool { return true }
 	}
+	if _, ok := zero.(*Empty); ok {
+		return func(v any) bool { return true }
+	}
 
 	switch reflect.TypeOf(zero).Kind() {
 	case reflect.String, reflect.Ptr:
@@ -26,7 +29,7 @@ func makeNilCheck(zero any) func(v any) bool {
 			return (*emptyInterface)(unsafe.Pointer(&v)).ptr == nil
 		}
 	case reflect.Slice:
-		// Return true for and nil slice.
+		// Return true for nil slice.
 		return func(v any) bool {
 			header := (*reflect.SliceHeader)((*emptyInterface)(unsafe.Pointer(&v)).ptr)
 			return header.Data == 0