Vue3 ( fix ) implement reactive args + fix many vue app creation issue

code/renderers/vue3/src/render.ts

@@ -1,5 +1,6 @@
 import { dedent } from 'ts-dedent';
-import { createApp, h } from 'vue';
+import type { App } from 'vue';
+import { createApp, h, reactive } from 'vue';
 import type { RenderContext, ArgsStoryFn } from '@storybook/types';
 
 import type { Args, StoryContext } from '@storybook/csf';
@@ -21,26 +22,24 @@ export const setup = (fn: (app: any) => void) => {
   setupFunction = fn;
 };
 
-const map = new Map<VueRenderer['canvasElement'], ReturnType<typeof createApp>>();
+const map = new Map<string, { vueApp: ReturnType<typeof createApp>; reactiveArgs: any }>();
 
 export function renderToCanvas(
-  { title, name, storyFn, showMain, showError, showException }: RenderContext<VueRenderer>,
+  {
+    storyFn,
+    name,
+    showMain,
+    showError,
+    showException,
+    id,
+    title,
+    forceRemount,
+    storyContext,
+  }: RenderContext<VueRenderer>,
   canvasElement: VueRenderer['canvasElement']
 ) {
   // TODO: explain cyclical nature of these app => story => mount
-  let element: StoryFnVueReturnType;
-  const storybookApp = createApp({
-    unmounted() {
-      map.delete(canvasElement);
-    },
-    render() {
-      map.set(canvasElement, storybookApp);
-      setupFunction(storybookApp);
-      return h(element);
-    },
-  });
-  storybookApp.config.errorHandler = (e: unknown) => showException(e as Error);
-  element = storyFn();
+  const element: StoryFnVueReturnType = storyFn();
 
   if (!element) {
     showError({
@@ -50,15 +49,39 @@ export function renderToCanvas(
       Use "() => ({ template: '<my-comp></my-comp>' })" or "() => ({ components: MyComp, template: '<my-comp></my-comp>' })" when defining the story.
       `,
     });
-    return;
+    return () => {};
   }
+  const { args: storyArgs, viewMode } = storyContext;
 
-  showMain();
+  const storyID = `${id}--${viewMode}`;
+  const existingApp = map.get(storyID);
+
+  if (existingApp && !forceRemount) {
+    updateArgs(existingApp.reactiveArgs, storyArgs);
+    return () => {
+      teardown(existingApp.vueApp, storyID);
+    };
+  }
 
-  map.get(canvasElement)?.unmount();
+  const reactiveArgs = storyArgs ? reactive(storyArgs) : storyArgs;
+
+  const storybookApp = createApp({
+    render() {
+      map.set(storyID, { vueApp: storybookApp, reactiveArgs });
+      return h(element, reactiveArgs);
+    },
+  });
 
+  storybookApp.config.errorHandler = (e: unknown) => showException(e as Error);
+  setupFunction(storybookApp);
   storybookApp.mount(canvasElement);
+
+  showMain();
+  return () => {
+    teardown(storybookApp, storyID);
+  };
 }
+
 /**
  * get the slots as functions to be rendered
  * @param props
@@ -73,3 +96,20 @@ function getSlots(props: Args, context: StoryContext<VueRenderer, Args>) {
 
   return Object.fromEntries(slots);
 }
+
+/**
+ *  update the reactive args
+ * @param reactiveArgs
+ * @param nextArgs
+ * @returns
+ */
+function updateArgs(reactiveArgs: Args, nextArgs: Args) {
+  if (!nextArgs) return;
+  // use spread operator to merge new args with the existing args
+  Object.assign(reactiveArgs, nextArgs);
+}
+
+function teardown(storybookApp: App<Element>, storyID: string) {
+  storybookApp?.unmount();
+  if (map.has(storyID)) map.delete(storyID);
+}