[Content collections] Remove experimental flag (#5825)

* refactor: remove experimental.cc from core

* chore: remove experimental flag from tests

* fix: mock contentDir in remark tests

* fix: check vfile.path in rel-image-error plugin

* fix: move .astro/ excludes to all test/fixtures

* fix: include test/**/fixtures in ignore

* chore: changeset

27 files changed, 58 insertions, 103 deletions

diff --git a/.changeset/thin-beers-drive.md b/.changeset/thin-beers-drive.md
new file mode 100644
index 000000000..d006e95fa
--- /dev/null
+++ b/.changeset/thin-beers-drive.md
@@ -0,0 +1,14 @@
+---
+'astro': major
+'@astrojs/mdx': major
+'@astrojs/markdown-remark': major
+---
+
+Baseline the experimental `contentCollections` flag. You're free to remove this from your astro config!
+
+```diff
+import { defineConfig } from 'astro/config';
+
+export default defineConfig({
+- experimental: { contentCollections: true }
+})
diff --git a/.gitignore b/.gitignore
index 0f5c68284..df661ac83 100644
--- a/.gitignore
+++ b/.gitignore
@@ -24,3 +24,7 @@ packages/integrations/**/.netlify/
 
 # exclude IntelliJ/WebStorm stuff
 .idea
+
+# ignore content collection generated files
+packages/**/test/**/fixtures/**/.astro/
+packages/**/test/**/fixtures/**/env.d.ts
diff --git a/examples/with-content/astro.config.mjs b/examples/with-content/astro.config.mjs
index e27ea0285..3b2f75c84 100644
--- a/examples/with-content/astro.config.mjs
+++ b/examples/with-content/astro.config.mjs
@@ -7,7 +7,4 @@ import sitemap from '@astrojs/sitemap';
 export default defineConfig({
 	site: 'https://example.com',
 	integrations: [mdx(), sitemap()],
-	experimental: {
-		contentCollections: true,
-	},
 });
diff --git a/packages/astro/src/@types/astro.ts b/packages/astro/src/@types/astro.ts
index 2f62409d3..75e75f6a3 100644
--- a/packages/astro/src/@types/astro.ts
+++ b/packages/astro/src/@types/astro.ts
@@ -83,7 +83,6 @@ export interface CLIFlags {
 	port?: number;
 	config?: string;
 	drafts?: boolean;
-	experimentalContentCollections?: boolean;
 }
 
 export interface BuildConfig {
@@ -911,34 +910,13 @@ export interface AstroUserConfig {
 	legacy?: object;
 
 	/**
-	 * @docs
 	 * @kind heading
 	 * @name Experimental Flags
 	 * @description
 	 * Astro offers experimental flags to give users early access to new features.
 	 * These flags are not guaranteed to be stable.
 	 */
-	experimental?: {
-		/**
-		 * @docs
-		 * @name experimental.contentCollections
-		 * @type {boolean}
-		 * @default `false`
-		 * @version 1.7.0
-		 * @description
-		 * Enable experimental support for [Content Collections](https://docs.astro.build/en/guides/content-collections/). This makes the `src/content/` directory a reserved directory for Astro to manage, and introduces the `astro:content` module for querying this content.
-		 *
-		 * To enable this feature, set `experimental.contentCollections` to `true` in your Astro config:
-		 *
-		 * ```js
-		 * {
-		 * 	experimental: {
-		 *		contentCollections: true,
-		 * 	},
-		 * }
-		 */
-		contentCollections?: boolean;
-	};
+	experimental?: object;
 
 	// Legacy options to be removed
 
diff --git a/packages/astro/src/core/build/generate.ts b/packages/astro/src/core/build/generate.ts
index 047831860..1a708aab3 100644
--- a/packages/astro/src/core/build/generate.ts
+++ b/packages/astro/src/core/build/generate.ts
@@ -349,7 +349,6 @@ async function generatePath(
 		logging,
 		markdown: {
 			...settings.config.markdown,
-			isExperimentalContentCollections: settings.config.experimental.contentCollections,
 			contentDir: getContentPaths(settings.config).contentDir,
 		},
 		mode: opts.mode,
diff --git a/packages/astro/src/core/build/static-build.ts b/packages/astro/src/core/build/static-build.ts
index 747ef360f..deb8a0b05 100644
--- a/packages/astro/src/core/build/static-build.ts
+++ b/packages/astro/src/core/build/static-build.ts
@@ -157,8 +157,7 @@ async function ssrBuild(opts: StaticBuildOptions, internals: BuildInternals, inp
 			}),
 			vitePluginPrerender(opts, internals),
 			...(viteConfig.plugins || []),
-			settings.config.experimental.contentCollections &&
-				astroBundleDelayedAssetPlugin({ internals }),
+			astroBundleDelayedAssetPlugin({ internals }),
 			// SSR needs to be last
 			ssr && vitePluginSSR(internals, settings.adapter!),
 		],
diff --git a/packages/astro/src/core/build/vite-plugin-css.ts b/packages/astro/src/core/build/vite-plugin-css.ts
index 68012948a..9398cf60a 100644
--- a/packages/astro/src/core/build/vite-plugin-css.ts
+++ b/packages/astro/src/core/build/vite-plugin-css.ts
@@ -76,15 +76,13 @@ export function rollupPluginAstroBuildCSS(options: PluginOptions): VitePlugin[]
 					// For CSS, create a hash of all of the pages that use it.
 					// This causes CSS to be built into shared chunks when used by multiple pages.
 					if (isCSSRequest(id)) {
-						if (settings.config.experimental.contentCollections) {
-							for (const [pageInfo] of walkParentInfos(id, {
-								getModuleInfo: args[0].getModuleInfo,
-							})) {
-								if (new URL(pageInfo.id, 'file://').searchParams.has(DELAYED_ASSET_FLAG)) {
-									// Split delayed assets to separate modules
-									// so they can be injected where needed
-									return createNameHash(id, [id]);
-								}
+						for (const [pageInfo] of walkParentInfos(id, {
+							getModuleInfo: args[0].getModuleInfo,
+						})) {
+							if (new URL(pageInfo.id, 'file://').searchParams.has(DELAYED_ASSET_FLAG)) {
+								// Split delayed assets to separate modules
+								// so they can be injected where needed
+								return createNameHash(id, [id]);
 							}
 						}
 						return createNameForParentPages(id, args[0]);
@@ -174,17 +172,10 @@ export function rollupPluginAstroBuildCSS(options: PluginOptions): VitePlugin[]
 										id,
 										this,
 										function until(importer) {
-											if (settings.config.experimental.contentCollections) {
-												// Short circuit when `contentCollections` is enabled.
-												return new URL(importer, 'file://').searchParams.has(DELAYED_ASSET_FLAG);
-											}
-											return false;
+											return new URL(importer, 'file://').searchParams.has(DELAYED_ASSET_FLAG);
 										}
 									)) {
-										if (
-											settings.config.experimental.contentCollections &&
-											new URL(pageInfo.id, 'file://').searchParams.has(DELAYED_ASSET_FLAG)
-										) {
+										if (new URL(pageInfo.id, 'file://').searchParams.has(DELAYED_ASSET_FLAG)) {
 											for (const parent of walkParentInfos(id, this)) {
 												const parentInfo = parent[0];
 												if (moduleIsTopLevelPage(parentInfo)) {
diff --git a/packages/astro/src/core/build/vite-plugin-ssr.ts b/packages/astro/src/core/build/vite-plugin-ssr.ts
index d9df28af2..817881c36 100644
--- a/packages/astro/src/core/build/vite-plugin-ssr.ts
+++ b/packages/astro/src/core/build/vite-plugin-ssr.ts
@@ -210,7 +210,6 @@ function buildManifest(
 		base: settings.config.base,
 		markdown: {
 			...settings.config.markdown,
-			isExperimentalContentCollections: settings.config.experimental.contentCollections,
 			contentDir: getContentPaths(settings.config).contentDir,
 		},
 		pageMap: null as any,
diff --git a/packages/astro/src/core/config/config.ts b/packages/astro/src/core/config/config.ts
index 5be492b40..394a968db 100644
--- a/packages/astro/src/core/config/config.ts
+++ b/packages/astro/src/core/config/config.ts
@@ -100,10 +100,6 @@ export function resolveFlags(flags: Partial<Flags>): CLIFlags {
 		host:
 			typeof flags.host === 'string' || typeof flags.host === 'boolean' ? flags.host : undefined,
 		drafts: typeof flags.drafts === 'boolean' ? flags.drafts : undefined,
-		experimentalContentCollections:
-			typeof flags.experimentalContentCollections === 'boolean'
-				? flags.experimentalContentCollections
-				: undefined,
 	};
 }
 
@@ -132,7 +128,6 @@ function mergeCLIFlags(astroConfig: AstroUserConfig, flags: CLIFlags) {
 		// TODO: Come back here and refactor to remove this expected error.
 		astroConfig.server.host = flags.host;
 	}
-	if (flags.experimentalContentCollections) astroConfig.experimental.contentCollections = true;
 	return astroConfig;
 }
 
diff --git a/packages/astro/src/core/config/schema.ts b/packages/astro/src/core/config/schema.ts
index bdf7d4e5d..eff69ca4a 100644
--- a/packages/astro/src/core/config/schema.ts
+++ b/packages/astro/src/core/config/schema.ts
@@ -34,9 +34,6 @@ const ASTRO_CONFIG_DEFAULTS: AstroUserConfig & any = {
 	},
 	vite: {},
 	legacy: {},
-	experimental: {
-		contentCollections: false,
-	},
 };
 
 export const AstroConfigSchema = z.object({
@@ -167,15 +164,7 @@ export const AstroConfigSchema = z.object({
 	vite: z
 		.custom<ViteUserConfig>((data) => data instanceof Object && !Array.isArray(data))
 		.default(ASTRO_CONFIG_DEFAULTS.vite),
-	experimental: z
-		.object({
-			contentCollections: z
-				.boolean()
-				.optional()
-				.default(ASTRO_CONFIG_DEFAULTS.experimental.contentCollections),
-		})
-		.optional()
-		.default({}),
+	experimental: z.object({}).optional().default({}),
 	legacy: z.object({}).optional().default({}),
 });
 
diff --git a/packages/astro/src/core/create-vite.ts b/packages/astro/src/core/create-vite.ts
index 05d591f42..1d33ba28f 100644
--- a/packages/astro/src/core/create-vite.ts
+++ b/packages/astro/src/core/create-vite.ts
@@ -104,13 +104,9 @@ export async function createVite(
 			astroHeadPropagationPlugin({ settings }),
 			astroScannerPlugin({ settings, logging }),
 			astroInjectEnvTsPlugin({ settings, logging, fs }),
-			...(settings.config.experimental.contentCollections
-				? [
-						astroContentVirtualModPlugin({ settings }),
-						astroContentServerPlugin({ fs, settings, logging, mode }),
-						astroDelayedAssetPlugin({ mode }),
-				  ]
-				: []),
+			astroContentVirtualModPlugin({ settings }),
+			astroContentServerPlugin({ fs, settings, logging, mode }),
+			astroDelayedAssetPlugin({ mode }),
 		],
 		publicDir: fileURLToPath(settings.config.publicDir),
 		root: fileURLToPath(settings.config.root),
diff --git a/packages/astro/src/core/render/dev/environment.ts b/packages/astro/src/core/render/dev/environment.ts
index c12495bf5..1704c6f29 100644
--- a/packages/astro/src/core/render/dev/environment.ts
+++ b/packages/astro/src/core/render/dev/environment.ts
@@ -24,7 +24,6 @@ export function createDevelopmentEnvironment(
 		logging,
 		markdown: {
 			...settings.config.markdown,
-			isExperimentalContentCollections: settings.config.experimental.contentCollections,
 			contentDir: getContentPaths(settings.config).contentDir,
 		},
 		mode,
diff --git a/packages/astro/src/vite-plugin-markdown/index.ts b/packages/astro/src/vite-plugin-markdown/index.ts
index 34ed3647b..6891bc0d5 100644
--- a/packages/astro/src/vite-plugin-markdown/index.ts
+++ b/packages/astro/src/vite-plugin-markdown/index.ts
@@ -71,7 +71,6 @@ export default function markdown({ settings, logging }: AstroPluginOptions): Plu
 				const renderResult = await renderMarkdown(raw.content, {
 					...settings.config.markdown,
 					fileURL: new URL(`file://${fileId}`),
-					isExperimentalContentCollections: settings.config.experimental.contentCollections,
 					contentDir: getContentPaths(settings.config).contentDir,
 					frontmatter: raw.data,
 				});
diff --git a/packages/astro/test/fixtures/.gitignore b/packages/astro/test/fixtures/.gitignore
deleted file mode 100644
index 7f0fa55b0..000000000
--- a/packages/astro/test/fixtures/.gitignore
+++ /dev/null
@@ -1,2 +0,0 @@
-.astro/
-env.d.ts
diff --git a/packages/astro/test/fixtures/content-collections/astro.config.mjs b/packages/astro/test/fixtures/content-collections/astro.config.mjs
index 6f20dd805..3f7b88523 100644
--- a/packages/astro/test/fixtures/content-collections/astro.config.mjs
+++ b/packages/astro/test/fixtures/content-collections/astro.config.mjs
@@ -4,7 +4,4 @@ import mdx from '@astrojs/mdx';
 // https://astro.build/config
 export default defineConfig({
 	integrations: [mdx()],
-	experimental: {
-		contentCollections: true,
-	},
 });
diff --git a/packages/astro/test/fixtures/content-ssr-integration/astro.config.mjs b/packages/astro/test/fixtures/content-ssr-integration/astro.config.mjs
index 6f20dd805..3f7b88523 100644
--- a/packages/astro/test/fixtures/content-ssr-integration/astro.config.mjs
+++ b/packages/astro/test/fixtures/content-ssr-integration/astro.config.mjs
@@ -4,7 +4,4 @@ import mdx from '@astrojs/mdx';
 // https://astro.build/config
 export default defineConfig({
 	integrations: [mdx()],
-	experimental: {
-		contentCollections: true,
-	},
 });
diff --git a/packages/astro/test/fixtures/content-static-paths-integration/astro.config.mjs b/packages/astro/test/fixtures/content-static-paths-integration/astro.config.mjs
index 6f20dd805..3f7b88523 100644
--- a/packages/astro/test/fixtures/content-static-paths-integration/astro.config.mjs
+++ b/packages/astro/test/fixtures/content-static-paths-integration/astro.config.mjs
@@ -4,7 +4,4 @@ import mdx from '@astrojs/mdx';
 // https://astro.build/config
 export default defineConfig({
 	integrations: [mdx()],
-	experimental: {
-		contentCollections: true,
-	},
 });
diff --git a/packages/astro/test/fixtures/content/astro.config.mjs b/packages/astro/test/fixtures/content/astro.config.mjs
index b331e201a..f6e805117 100644
--- a/packages/astro/test/fixtures/content/astro.config.mjs
+++ b/packages/astro/test/fixtures/content/astro.config.mjs
@@ -3,5 +3,4 @@ import mdx from '@astrojs/mdx';
 
 export default defineConfig({
   integrations: [mdx()],
-	experimental: { contentCollections: true },
 });
diff --git a/packages/astro/test/units/dev/collections-renderentry.test.js b/packages/astro/test/units/dev/collections-renderentry.test.js
index 072d004fa..fa720f97b 100644
--- a/packages/astro/test/units/dev/collections-renderentry.test.js
+++ b/packages/astro/test/units/dev/collections-renderentry.test.js
@@ -47,7 +47,6 @@ describe('Content Collections - render()', () => {
 				userConfig: {
 					integrations: [mdx()],
 					vite: { server: { middlewareMode: true } },
-					experimental: { contentCollections: true },
 				},
 			},
 			async (container) => {
@@ -121,7 +120,6 @@ describe('Content Collections - render()', () => {
 				userConfig: {
 					integrations: [mdx()],
 					vite: { server: { middlewareMode: true } },
-					experimental: { contentCollections: true },
 				},
 			},
 			async (container) => {
@@ -193,7 +191,6 @@ describe('Content Collections - render()', () => {
 				userConfig: {
 					integrations: [mdx()],
 					vite: { server: { middlewareMode: true } },
-					experimental: { contentCollections: true },
 				},
 			},
 			async (container) => {
@@ -259,7 +256,6 @@ describe('Content Collections - render()', () => {
 				userConfig: {
 					integrations: [mdx()],
 					vite: { server: { middlewareMode: true } },
-					experimental: { contentCollections: true },
 				},
 			},
 			async (container) => {
diff --git a/packages/integrations/mdx/src/plugins.ts b/packages/integrations/mdx/src/plugins.ts
index 6637b57d7..6b97bc77c 100644
--- a/packages/integrations/mdx/src/plugins.ts
+++ b/packages/integrations/mdx/src/plugins.ts
@@ -161,9 +161,8 @@ export async function getRemarkPlugins(
 	remarkPlugins = [...remarkPlugins, ...ignoreStringPlugins(mdxOptions.remarkPlugins)];
 
 	// Apply last in case user plugins resolve relative image paths
-	if (config.experimental.contentCollections) {
-		remarkPlugins.push(toRemarkContentRelImageError(config));
-	}
+	remarkPlugins.push(toRemarkContentRelImageError(config));
+
 	return remarkPlugins;
 }
 
diff --git a/packages/markdown/remark/src/index.ts b/packages/markdown/remark/src/index.ts
index 91680f3fd..fdd669280 100644
--- a/packages/markdown/remark/src/index.ts
+++ b/packages/markdown/remark/src/index.ts
@@ -53,7 +53,6 @@ export async function renderMarkdown(
 		remarkRehype = markdownConfigDefaults.remarkRehype,
 		gfm = markdownConfigDefaults.gfm,
 		smartypants = markdownConfigDefaults.smartypants,
-		isExperimentalContentCollections = false,
 		contentDir,
 		frontmatter: userFrontmatter = {},
 	} = opts;
@@ -91,9 +90,7 @@ export async function renderMarkdown(
 	}
 
 	// Apply later in case user plugins resolve relative image paths
-	if (isExperimentalContentCollections) {
-		parser.use([toRemarkContentRelImageError({ contentDir })]);
-	}
+	parser.use([toRemarkContentRelImageError({ contentDir })]);
 
 	parser.use([
 		[
diff --git a/packages/markdown/remark/src/remark-content-rel-image-error.ts b/packages/markdown/remark/src/remark-content-rel-image-error.ts
index 1a0870c22..3e3664b20 100644
--- a/packages/markdown/remark/src/remark-content-rel-image-error.ts
+++ b/packages/markdown/remark/src/remark-content-rel-image-error.ts
@@ -10,6 +10,8 @@ import type { VFile } from 'vfile';
 export default function toRemarkContentRelImageError({ contentDir }: { contentDir: URL }) {
 	return function remarkContentRelImageError() {
 		return (tree: any, vfile: VFile) => {
+			if (typeof vfile?.path !== 'string') return;
+
 			const isContentFile = pathToFileURL(vfile.path).href.startsWith(contentDir.href);
 			if (!isContentFile) return;
 
diff --git a/packages/markdown/remark/src/types.ts b/packages/markdown/remark/src/types.ts
index 40b2ac841..ff3060704 100644
--- a/packages/markdown/remark/src/types.ts
+++ b/packages/markdown/remark/src/types.ts
@@ -59,8 +59,6 @@ export interface MarkdownRenderingOptions extends AstroMarkdownOptions {
 		scopedClassName: string | null;
 	};
 	/** Used to prevent relative image imports from `src/content/` */
-	isExperimentalContentCollections?: boolean;
-	/** Used to prevent relative image imports from `src/content/` */
 	contentDir: URL;
 	/** Used for frontmatter injection plugins */
 	frontmatter?: Record<string, any>;
diff --git a/packages/markdown/remark/test/autolinking.test.js b/packages/markdown/remark/test/autolinking.test.js
index 48bf894be..b1e567bb4 100644
--- a/packages/markdown/remark/test/autolinking.test.js
+++ b/packages/markdown/remark/test/autolinking.test.js
@@ -1,10 +1,14 @@
 import { renderMarkdown } from '../dist/index.js';
 import chai from 'chai';
+import { mockRenderMarkdownParams } from './test-utils.js';
 
 describe('autolinking', () => {
 	describe('plain md', () => {
 		it('autolinks URLs starting with a protocol in plain text', async () => {
-			const { code } = await renderMarkdown(`See https://example.com for more.`, {});
+			const { code } = await renderMarkdown(
+				`See https://example.com for more.`,
+				mockRenderMarkdownParams
+			);
 
 			chai
 				.expect(code.replace(/\n/g, ''))
@@ -12,7 +16,10 @@ describe('autolinking', () => {
 		});
 
 		it('autolinks URLs starting with "www." in plain text', async () => {
-			const { code } = await renderMarkdown(`See www.example.com for more.`, {});
+			const { code } = await renderMarkdown(
+				`See www.example.com for more.`,
+				mockRenderMarkdownParams
+			);
 
 			chai
 				.expect(code.trim())
@@ -22,7 +29,7 @@ describe('autolinking', () => {
 		it('does not autolink URLs in code blocks', async () => {
 			const { code } = await renderMarkdown(
 				'See `https://example.com` or `www.example.com` for more.',
-				{}
+				mockRenderMarkdownParams
 			);
 
 			chai
diff --git a/packages/markdown/remark/test/entities.test.js b/packages/markdown/remark/test/entities.test.js
index d35ed3a89..acaf71be1 100644
--- a/packages/markdown/remark/test/entities.test.js
+++ b/packages/markdown/remark/test/entities.test.js
@@ -1,9 +1,13 @@
 import { renderMarkdown } from '../dist/index.js';
 import { expect } from 'chai';
+import { mockRenderMarkdownParams } from './test-utils.js';
 
 describe('entities', () => {
 	it('should not unescape entities in regular Markdown', async () => {
-		const { code } = await renderMarkdown(`&lt;i&gt;This should NOT be italic&lt;/i&gt;`, {});
+		const { code } = await renderMarkdown(
+			`&lt;i&gt;This should NOT be italic&lt;/i&gt;`,
+			mockRenderMarkdownParams
+		);
 
 		expect(code).to.equal(`<p>&#x3C;i>This should NOT be italic&#x3C;/i></p>`);
 	});
diff --git a/packages/markdown/remark/test/plugins.test.js b/packages/markdown/remark/test/plugins.test.js
index a1abeb2ed..35e5dcaf8 100644
--- a/packages/markdown/remark/test/plugins.test.js
+++ b/packages/markdown/remark/test/plugins.test.js
@@ -1,4 +1,5 @@
 import { renderMarkdown } from '../dist/index.js';
+import { mockRenderMarkdownParams } from './test-utils.js';
 import chai from 'chai';
 
 import { fileURLToPath } from 'node:url';
@@ -8,6 +9,7 @@ describe('plugins', () => {
 	it('should be able to get file path when passing fileURL', async () => {
 		let context;
 		await renderMarkdown(`test`, {
+			...mockRenderMarkdownParams,
 			fileURL: new URL('virtual.md', import.meta.url),
 			remarkPlugins: [
 				function () {
diff --git a/packages/markdown/remark/test/test-utils.js b/packages/markdown/remark/test/test-utils.js
new file mode 100644
index 000000000..10b779a7d
--- /dev/null
+++ b/packages/markdown/remark/test/test-utils.js
@@ -0,0 +1,3 @@
+export const mockRenderMarkdownParams = {
+	contentDir: new URL('file:///src/content/'),
+};