refactor: remove deprecated docs homePageId option (#6065)

packages/docusaurus-plugin-content-docs/src/options.ts

@@ -30,7 +30,6 @@ export const DEFAULT_OPTIONS: Omit<PluginOptions, 'id' | 'sidebarPath'> = {
   path: 'docs', // Path to data on filesystem, relative to site dir.
   routeBasePath: 'docs', // URL Route.
   tagsBasePath: 'tags', // URL Tags Route.
-  homePageId: undefined, // TODO remove soon, deprecated
   include: ['**/*.{md,mdx}'], // Extensions to include.
   exclude: GlobExcludeDefault,
   sidebarItemsGenerator: DefaultSidebarItemsGenerator,
@@ -79,7 +78,11 @@ export const OptionsSchema = Joi.object({
     // .allow('') ""
     .default(DEFAULT_OPTIONS.routeBasePath),
   tagsBasePath: Joi.string().default(DEFAULT_OPTIONS.tagsBasePath),
-  homePageId: Joi.string().optional(),
+  homePageId: Joi.any().forbidden().messages({
+    'any.unknown':
+      'The docs plugin option homePageId is not supported anymore. To make a doc the "home", please add "slug: /" in its front matter. See: https://docusaurus.io/docs/next/docs-introduction#home-page-docs',
+  }),
+
   include: Joi.array().items(Joi.string()).default(DEFAULT_OPTIONS.include),
   exclude: Joi.array().items(Joi.string()).default(DEFAULT_OPTIONS.exclude),
   sidebarPath: Joi.alternatives().try(
@@ -165,16 +168,6 @@ export function validateOptions({
     }
   }
 
-  // TODO remove homePageId before end of 2020
-  // "slug: /" is better because the home doc can be different across versions
-  if (options.homePageId) {
-    console.log(
-      chalk.red(
-        `The docs plugin option homePageId=${options.homePageId} is deprecated. To make a doc the "home", prefer frontmatter: "slug: /"`,
-      ),
-    );
-  }
-
   const normalizedOptions = validate(OptionsSchema, options);
 
   if (normalizedOptions.admonitions) {