Vue: Improve types for array, union and intersection when using vue-docgen-api

code/frameworks/vue3-vite/src/types.ts

@@ -1,9 +1,16 @@
 import type { BuilderOptions, StorybookConfigVite } from '@storybook/builder-vite';
 import type { StorybookConfig as StorybookConfigBase } from '@storybook/types';
+import type { ComponentMeta } from 'vue-component-meta';
+import type { ComponentDoc } from 'vue-docgen-api';
 
 type FrameworkName = '@storybook/vue3-vite';
 type BuilderName = '@storybook/builder-vite';
 
+/**
+ * Available docgen plugins for vue.
+ */
+export type VueDocgenPlugin = 'vue-docgen-api' | 'vue-component-meta';
+
 export type FrameworkOptions = {
   builder?: BuilderOptions;
   /**
@@ -14,7 +21,7 @@ export type FrameworkOptions = {
    * "vue-component-meta" will become the new default in the future and "vue-docgen-api" will be removed.
    * @default "vue-docgen-api"
    */
-  docgen?: 'vue-docgen-api' | 'vue-component-meta';
+  docgen?: VueDocgenPlugin;
 };
 
 type StorybookConfigFramework = {
@@ -43,3 +50,37 @@ export type StorybookConfig = Omit<
 > &
   StorybookConfigVite &
   StorybookConfigFramework;
+
+/**
+ * Gets the type of a single array element.
+ */
+type ArrayElement<T> = T extends readonly (infer A)[] ? A : never;
+
+/**
+ * Type of "__docgenInfo" depending on the used docgenPlugin.
+ */
+export type VueDocgenInfo<T extends VueDocgenPlugin> = T extends 'vue-component-meta'
+  ? ComponentMeta
+  : ComponentDoc;
+
+/**
+ * Single prop/event/slot/exposed entry of "__docgenInfo" depending on the used docgenPlugin.
+ *
+ * @example
+ * ```ts
+ * type PropInfo = VueDocgenInfoEntry<"vue-component-meta", "props">;
+ * ```
+ */
+export type VueDocgenInfoEntry<
+  T extends VueDocgenPlugin,
+  TKey extends 'props' | 'events' | 'slots' | 'exposed' | 'expose' =
+    | 'props'
+    | 'events'
+    | 'slots'
+    | 'exposed'
+    | 'expose',
+> = ArrayElement<
+  T extends 'vue-component-meta'
+    ? VueDocgenInfo<'vue-component-meta'>[Exclude<TKey, 'expose'>]
+    : VueDocgenInfo<'vue-docgen-api'>[Exclude<TKey, 'exposed'>]
+>;

code/lib/docs-tools/src/argTypes/docgen/utils/docgenInfo.ts

@@ -3,7 +3,9 @@
 import type { Component } from '../../types';
 import { str } from './string';
 
-export function hasDocgen(component: Component): boolean {
+export function hasDocgen<T = any>(
+  component: Component
+): component is object & { __docgenInfo: T } {
   return !!component.__docgenInfo;
 }