Merge pull request #32216 from storybookjs/valentin/add-error-handling-to-mock-preview-parsing

valentinpalkovic · web-flow · commit 906ad720e2ca · 2025-08-07T13:19:00.000+02:00
Mock: Catch errors when transforming preview files
diff --git a/code/core/src/core-server/presets/vitePlugins/vite-mock/plugin.ts b/code/core/src/core-server/presets/vitePlugins/vite-mock/plugin.ts
@@ -167,7 +167,12 @@ export function viteMockPlugin(options: MockPluginOptions): Plugin[] {
       name: 'storybook:mock-loader-preview',
       transform(code, id) {
         if (id === normalizedPreviewConfigPath) {
-          return rewriteSbMockImportCalls(code);
+          try {
+            return rewriteSbMockImportCalls(code);
+          } catch (e) {
+            logger.debug(`Could not transform sb.mock(import(...)) calls in ${id}: ${e}`);
+            return null;
+          }
         }
         return null;
       },
diff --git a/code/core/src/core-server/presets/webpack/loaders/storybook-mock-transform-loader.ts b/code/core/src/core-server/presets/webpack/loaders/storybook-mock-transform-loader.ts
@@ -1,15 +1,30 @@
-import type { LoaderContext } from 'webpack';
+import { logger } from 'storybook/internal/node-logger';
+
+import type { LoaderDefinition } from 'webpack';
 
 import { rewriteSbMockImportCalls } from '../../../mocking-utils/extract';
 
 /**
  * A Webpack loader that normalize sb.mock(import(...)) calls to sb.mock(...)
  *
- * @param {string} source The original source code of the preview config file.
- * @this {LoaderContext<{}>} The Webpack loader context.
+ * @param source The original source code of the preview config file.
+ * @this The Webpack loader context.
  */
-export default function storybookMockTransformLoader(this: LoaderContext<{}>, source: string) {
-  const result = rewriteSbMockImportCalls(source);
+const storybookMockTransformLoader: LoaderDefinition = function mockTransformLoaderFn(
+  source,
+  sourceMap,
+  meta
+) {
   const callback = this.async();
-  callback(null, result.code, result.map || undefined);
-}
+
+  try {
+    const result = rewriteSbMockImportCalls(source);
+    callback(null, result.code, result.map || undefined, meta);
+  } catch (error) {
+    const filePath = this.resourcePath;
+    logger.debug(`Could not transform sb.mock(import(...)) calls in ${filePath}: ${error}`);
+    callback(null, source, sourceMap, meta);
+  }
+};
+
+export default storybookMockTransformLoader;
