Module format load: Move story decorators out of parameters

examples/official-storybook/stories/addon-info/options.stories.js

@@ -140,9 +140,7 @@ export const useInfoAsStoryDecorator = () => <BaseButton label="Button" />;
 
 useInfoAsStoryDecorator.story = {
   name: 'Use Info as story decorator',
-  parameters: {
+  decorators: [withInfo('Info can take options via the global or local decorator as well.')],
-    decorators: [withInfo('Info can take options via the global or local decorator as well.')],
-  },
 };
 
 export const usingParamatersAcrossAllStories = () => <BaseButton label="Button" />;

examples/official-storybook/stories/core/decorators.stories.js

@@ -28,11 +28,23 @@ export default {
 
 export const all = () => <p>Story</p>;
 all.story = {
+  decorators: [
+    s => (
+      <>
+        <p>Local Decorator</p>
+        {s()}
+      </>
+    ),
+  ],
+};
+
+export const deprecated = () => <p>Story</p>;
+deprecated.story = {
   parameters: {
     decorators: [
       s => (
         <>
-          <p>Local Decorator</p>
+          <p>Deprecated Local Decorator</p>
           {s()}
         </>
       ),

lib/core/src/client/preview/start.js

@@ -349,8 +349,13 @@ export default function start(render, { decorateStory } = {}) {
       Object.keys(exports).forEach(key => {
         if (isExportStory(key, meta)) {
           const storyFn = exports[key];
-          const { name, parameters } = storyFn.story || {};
+          const { name, parameters, decorators } = storyFn.story || {};
-          kind.add(name || key, storyFn, parameters);
+          if (parameters && parameters.decorators) {
+            deprecate(() => {},
+            `${kindName} => ${name || key}: story.parameters.decorators is deprecated; use story.decorators instead.`)();
+          }
+          const decoratorParams = decorators ? { decorators } : null;
+          kind.add(name || key, storyFn, { ...parameters, ...decoratorParams });
         }
       });