upd

Author: danylo-safonov-solid

tools/add_imports/bin/add_imports.dart

@@ -27,10 +27,7 @@ void main(List<String> arguments) {
 
     final imports = classes.map(
       (classname) {
-        final filename = config.classesMap.entries
-            .firstWhere((e) => e.value.contains(classname))
-            .key;
-
+        final filename = config.filenameForClass(classname);
         final url = '${config.fileUrlPrefix}$filename';
 
         return 'import { $classname } from "$url";';

tools/add_imports/lib/src/config.dart

@@ -21,4 +21,7 @@ class Config {
       fileUrlPrefix: parsedYaml['file_url_prefix'] as String,
     );
   }
+
+  String filenameForClass(String classname) =>
+      classesMap.entries.firstWhere((e) => e.value.contains(classname)).key;
 }