From a1ff4a3604fd4f3d85701bdf8b6e5b3d3a35f45a Mon Sep 17 00:00:00 2001
From: Florian Lefebvre <contact@florian-lefebvre.dev>
Date: Tue, 15 Oct 2024 17:06:55 +0200
Subject: [PATCH 01/17] feat(next): make defineConfig generic

---
 packages/astro/config.d.ts | 17 ++++++++++++++++-
 1 file changed, 16 insertions(+), 1 deletion(-)

diff --git a/packages/astro/config.d.ts b/packages/astro/config.d.ts
index de2a500c25b2..abb31c015827 100644
--- a/packages/astro/config.d.ts
+++ b/packages/astro/config.d.ts
@@ -11,7 +11,22 @@ type EnvField = typeof import('./dist/env/config.js').envField;
  * See the full Astro Configuration API Documentation
  * https://astro.build/config
  */
-export function defineConfig(config: AstroUserConfig): AstroUserConfig;
+// TODO: jsdoc for overridden properties
+export function defineConfig<
+	TDefaultLocale extends string,
+	const TLocales extends [TDefaultLocale, ...Array<string>],
+>(
+	config: Omit<AstroUserConfig, 'i18n'> & {
+		i18n?: {
+			defaultLocale: TDefaultLocale;
+			locales: TLocales;
+			fallback?: {
+				[Locale in TLocales[number]]?: Exclude<TLocales[number], Locale>;
+			};
+			domains?: Partial<Record<TLocales[number], string>>;
+		} & Pick<NonNullable<AstroUserConfig['i18n']>, 'routing'>;
+	},
+): AstroUserConfig;
 
 /**
  * Use Astro to generate a fully resolved Vite config

From b627d82cec45d21516f70e7a0431c6d2841c4396 Mon Sep 17 00:00:00 2001
From: Florian Lefebvre <contact@florian-lefebvre.dev>
Date: Wed, 16 Oct 2024 16:37:22 +0200
Subject: [PATCH 02/17] feat: work on generic type

---
 packages/astro/config.d.ts                | 18 +++---------------
 packages/astro/src/config/index.ts        | 12 +++++++++++-
 packages/astro/src/types/public/config.ts | 20 +++++++++++++++-----
 3 files changed, 29 insertions(+), 21 deletions(-)

diff --git a/packages/astro/config.d.ts b/packages/astro/config.d.ts
index abb31c015827..256a1c82ffc8 100644
--- a/packages/astro/config.d.ts
+++ b/packages/astro/config.d.ts
@@ -11,22 +11,10 @@ type EnvField = typeof import('./dist/env/config.js').envField;
  * See the full Astro Configuration API Documentation
  * https://astro.build/config
  */
-// TODO: jsdoc for overridden properties
 export function defineConfig<
-	TDefaultLocale extends string,
-	const TLocales extends [TDefaultLocale, ...Array<string>],
->(
-	config: Omit<AstroUserConfig, 'i18n'> & {
-		i18n?: {
-			defaultLocale: TDefaultLocale;
-			locales: TLocales;
-			fallback?: {
-				[Locale in TLocales[number]]?: Exclude<TLocales[number], Locale>;
-			};
-			domains?: Partial<Record<TLocales[number], string>>;
-		} & Pick<NonNullable<AstroUserConfig['i18n']>, 'routing'>;
-	},
-): AstroUserConfig;
+		TDefaultLocale extends string,
+		const TLocales extends [TDefaultLocale, ...Array<string>],
+	>(config: AstroUserConfig<TDefaultLocale, TLocales>): AstroUserConfig<TDefaultLocale, TLocales>;
 
 /**
  * Use Astro to generate a fully resolved Vite config
diff --git a/packages/astro/src/config/index.ts b/packages/astro/src/config/index.ts
index 77c33fcc5ffc..f3d6745535a2 100644
--- a/packages/astro/src/config/index.ts
+++ b/packages/astro/src/config/index.ts
@@ -4,10 +4,20 @@ import { createRouteManifest } from '../core/routing/index.js';
 import type { AstroInlineConfig, AstroUserConfig } from '../types/public/config.js';
 import { createDevelopmentManifest } from '../vite-plugin-astro-server/plugin.js';
 
-export function defineConfig(config: AstroUserConfig) {
+export function defineConfig<
+	TDefaultLocale extends string,
+	const TLocales extends [TDefaultLocale, ...Array<string>],
+>(config: AstroUserConfig<TDefaultLocale, TLocales>) {
 	return config;
 }
 
+defineConfig({
+	i18n: {
+		defaultLocale: 'en',
+		locales: ['en', 'fr'],
+	},
+});
+
 export function getViteConfig(
 	userViteConfig: ViteUserConfig,
 	inlineAstroConfig: AstroInlineConfig = {},
diff --git a/packages/astro/src/types/public/config.ts b/packages/astro/src/types/public/config.ts
index 66be4037b2b3..5c7c2af44a6a 100644
--- a/packages/astro/src/types/public/config.ts
+++ b/packages/astro/src/types/public/config.ts
@@ -102,7 +102,10 @@ export interface ViteUserConfig extends OriginalViteUserConfig {
  * Astro User Config
  * Docs: https://docs.astro.build/reference/configuration-reference/
  */
-export interface AstroUserConfig {
+export interface AstroUserConfig<
+	TDefaultLocale extends string = never,
+	TLocales extends [TDefaultLocale, ...Array<string>] = never,
+> {
 	/**
 	 * @docs
 	 * @kind heading
@@ -1214,7 +1217,7 @@ export interface AstroUserConfig {
 		 *
 		 * No particular language format or syntax is enforced, but we suggest using lower-case and hyphens as needed (e.g. "es", "pt-br") for greatest compatibility.
 		 */
-		defaultLocale: string;
+		defaultLocale: [TDefaultLocale] extends [never] ? string : TDefaultLocale;
 		/**
 		 * @docs
 		 * @name i18n.locales
@@ -1228,7 +1231,8 @@ export interface AstroUserConfig {
 		 *
 		 * No particular language code format or syntax is enforced, but your project folders containing your content files must match exactly the `locales` items in the list. In the case of multiple `codes` pointing to a custom URL path prefix, store your content files in a folder with the same name as the `path` configured.
 		 */
-		locales: Locales;
+		// TODO: handle Locales shape
+		locales: [TLocales] extends [never] ? Locales : TLocales;
 
 		/**
 		 * @docs
@@ -1258,7 +1262,11 @@ export interface AstroUserConfig {
 		 * })
 		 * ```
 		 */
-		fallback?: Record<string, string>;
+		fallback?: [TLocales] extends [never]
+			? Record<string, string>
+			: {
+					[Locale in TLocales[number]]?: Exclude<TLocales[number], Locale>;
+				};
 
 		/**
 		 * @docs
@@ -1444,7 +1452,9 @@ export interface AstroUserConfig {
 		 *
 		 * See the [Internationalization Guide](https://docs.astro.build/en/guides/internationalization/#domains) for more details, including the limitations of this feature.
 		 */
-		domains?: Record<string, string>;
+		domains?: [TLocales] extends [never]
+			? Record<string, string>
+			: Partial<Record<TLocales[number], string>>;
 	};
 
 	/** ! WARNING: SUBJECT TO CHANGE */

From 76d6e6b1751e4c224e832977eacc0aedc604a4c3 Mon Sep 17 00:00:00 2001
From: Florian Lefebvre <contact@florian-lefebvre.dev>
Date: Wed, 16 Oct 2024 16:50:06 +0200
Subject: [PATCH 03/17] feat: handle locales shape

---
 packages/astro/config.d.ts                |  6 +++++-
 packages/astro/src/config/index.ts        | 14 +++++---------
 packages/astro/src/types/public/config.ts | 17 ++++++++++++++---
 3 files changed, 24 insertions(+), 13 deletions(-)

diff --git a/packages/astro/config.d.ts b/packages/astro/config.d.ts
index 256a1c82ffc8..dfa17726e570 100644
--- a/packages/astro/config.d.ts
+++ b/packages/astro/config.d.ts
@@ -2,6 +2,7 @@
 type ViteUserConfig = import('vite').UserConfig;
 type ViteUserConfigFn = import('vite').UserConfigFn;
 type AstroUserConfig = import('./dist/types/public/config.js').AstroUserConfig;
+type Locales = import('./dist/types/public/config.js').Locales;
 type AstroInlineConfig = import('./dist/types/public/config.js').AstroInlineConfig;
 type ImageServiceConfig = import('./dist/types/public/config.js').ImageServiceConfig;
 type SharpImageServiceConfig = import('./dist/assets/services/sharp.js').SharpImageServiceConfig;
@@ -13,7 +14,10 @@ type EnvField = typeof import('./dist/env/config.js').envField;
  */
 export function defineConfig<
 		TDefaultLocale extends string,
-		const TLocales extends [TDefaultLocale, ...Array<string>],
+		const TLocales extends [
+			TDefaultLocale | { codes: [TDefaultLocale, ...Array<string>]; path: string },
+			...Locales,
+		],
 	>(config: AstroUserConfig<TDefaultLocale, TLocales>): AstroUserConfig<TDefaultLocale, TLocales>;
 
 /**
diff --git a/packages/astro/src/config/index.ts b/packages/astro/src/config/index.ts
index f3d6745535a2..00f4197d8ccb 100644
--- a/packages/astro/src/config/index.ts
+++ b/packages/astro/src/config/index.ts
@@ -1,23 +1,19 @@
 import type { UserConfig as ViteUserConfig } from 'vite';
 import { Logger } from '../core/logger/core.js';
 import { createRouteManifest } from '../core/routing/index.js';
-import type { AstroInlineConfig, AstroUserConfig } from '../types/public/config.js';
+import type { AstroInlineConfig, AstroUserConfig, Locales } from '../types/public/config.js';
 import { createDevelopmentManifest } from '../vite-plugin-astro-server/plugin.js';
 
 export function defineConfig<
 	TDefaultLocale extends string,
-	const TLocales extends [TDefaultLocale, ...Array<string>],
+	const TLocales extends [
+		TDefaultLocale | { codes: [TDefaultLocale, ...Array<string>]; path: string },
+		...Locales,
+	],
 >(config: AstroUserConfig<TDefaultLocale, TLocales>) {
 	return config;
 }
 
-defineConfig({
-	i18n: {
-		defaultLocale: 'en',
-		locales: ['en', 'fr'],
-	},
-});
-
 export function getViteConfig(
 	userViteConfig: ViteUserConfig,
 	inlineAstroConfig: AstroInlineConfig = {},
diff --git a/packages/astro/src/types/public/config.ts b/packages/astro/src/types/public/config.ts
index 5c7c2af44a6a..64a1a68356fc 100644
--- a/packages/astro/src/types/public/config.ts
+++ b/packages/astro/src/types/public/config.ts
@@ -16,6 +16,14 @@ import type { AstroIntegration } from './integrations.js';
 
 export type Locales = (string | { codes: string[]; path: string })[];
 
+type NormalizeLocales<T extends Locales> = {
+	[K in keyof T]: T[K] extends string
+		? T[K]
+		: T[K] extends { codes: Array<string> }
+			? T[K]['codes'][number]
+			: never;
+}[number];
+
 export interface ImageServiceConfig<T extends Record<string, any> = Record<string, any>> {
 	entrypoint: 'astro/assets/services/sharp' | (string & {});
 	config?: T;
@@ -104,7 +112,10 @@ export interface ViteUserConfig extends OriginalViteUserConfig {
  */
 export interface AstroUserConfig<
 	TDefaultLocale extends string = never,
-	TLocales extends [TDefaultLocale, ...Array<string>] = never,
+	TLocales extends [
+		TDefaultLocale | { codes: [TDefaultLocale, ...Array<string>]; path: string },
+		...Locales,
+	] = never,
 > {
 	/**
 	 * @docs
@@ -1265,7 +1276,7 @@ export interface AstroUserConfig<
 		fallback?: [TLocales] extends [never]
 			? Record<string, string>
 			: {
-					[Locale in TLocales[number]]?: Exclude<TLocales[number], Locale>;
+					[Locale in NormalizeLocales<TLocales>]?: Exclude<NormalizeLocales<TLocales>, Locale>;
 				};
 
 		/**
@@ -1454,7 +1465,7 @@ export interface AstroUserConfig<
 		 */
 		domains?: [TLocales] extends [never]
 			? Record<string, string>
-			: Partial<Record<TLocales[number], string>>;
+			: Partial<Record<NormalizeLocales<TLocales>, string>>;
 	};
 
 	/** ! WARNING: SUBJECT TO CHANGE */

From 348def6429b5681c460cf5de5b3f58daae8fde07 Mon Sep 17 00:00:00 2001
From: Florian Lefebvre <contact@florian-lefebvre.dev>
Date: Wed, 16 Oct 2024 16:51:10 +0200
Subject: [PATCH 04/17] chore: remove todo

---
 packages/astro/src/types/public/config.ts | 1 -
 1 file changed, 1 deletion(-)

diff --git a/packages/astro/src/types/public/config.ts b/packages/astro/src/types/public/config.ts
index 64a1a68356fc..5c7b0ba0f30a 100644
--- a/packages/astro/src/types/public/config.ts
+++ b/packages/astro/src/types/public/config.ts
@@ -1242,7 +1242,6 @@ export interface AstroUserConfig<
 		 *
 		 * No particular language code format or syntax is enforced, but your project folders containing your content files must match exactly the `locales` items in the list. In the case of multiple `codes` pointing to a custom URL path prefix, store your content files in a folder with the same name as the `path` configured.
 		 */
-		// TODO: handle Locales shape
 		locales: [TLocales] extends [never] ? Locales : TLocales;
 
 		/**

From c9b6ca59b90799dc01768403043859d887255b54 Mon Sep 17 00:00:00 2001
From: Florian Lefebvre <contact@florian-lefebvre.dev>
Date: Wed, 16 Oct 2024 16:52:59 +0200
Subject: [PATCH 05/17] chore: changeset

---
 .changeset/forty-trains-notice.md | 9 +++++++++
 1 file changed, 9 insertions(+)
 create mode 100644 .changeset/forty-trains-notice.md

diff --git a/.changeset/forty-trains-notice.md b/.changeset/forty-trains-notice.md
new file mode 100644
index 000000000000..f722b7e1a7ae
--- /dev/null
+++ b/.changeset/forty-trains-notice.md
@@ -0,0 +1,9 @@
+---
+'astro': minor
+---
+
+Makes `defineConfig` generic
+
+TypeScript will now provide feedback at the type level when using `defineConfig`. For example, it will make sure `i18n.locales` contains `i18n.defaultLocale`.
+
+This also makes the `AstroUserConfig` generic, but both changes are backward compatible.

From 42f4cd4bf75ff43e52a9d7377303657df3160ffb Mon Sep 17 00:00:00 2001
From: Florian Lefebvre <contact@florian-lefebvre.dev>
Date: Wed, 16 Oct 2024 20:21:05 +0200
Subject: [PATCH 06/17] feat: accept 1 generic

---
 packages/astro/config.d.ts                | 13 +++++--------
 packages/astro/src/config/index.ts        | 12 ++++--------
 packages/astro/src/types/public/config.ts | 21 +++++++++++----------
 3 files changed, 20 insertions(+), 26 deletions(-)

diff --git a/packages/astro/config.d.ts b/packages/astro/config.d.ts
index dfa17726e570..36883c867d3d 100644
--- a/packages/astro/config.d.ts
+++ b/packages/astro/config.d.ts
@@ -1,8 +1,9 @@
 /// <reference path='./client.d.ts' />
 type ViteUserConfig = import('vite').UserConfig;
 type ViteUserConfigFn = import('vite').UserConfigFn;
-type AstroUserConfig = import('./dist/types/public/config.js').AstroUserConfig;
 type Locales = import('./dist/types/public/config.js').Locales;
+type AstroUserDefineConfig<TLocales extends Locales> =
+	import('./dist/types/public/config.js').AstroUserDefineConfig<TLocales>;
 type AstroInlineConfig = import('./dist/types/public/config.js').AstroInlineConfig;
 type ImageServiceConfig = import('./dist/types/public/config.js').ImageServiceConfig;
 type SharpImageServiceConfig = import('./dist/assets/services/sharp.js').SharpImageServiceConfig;
@@ -12,13 +13,9 @@ type EnvField = typeof import('./dist/env/config.js').envField;
  * See the full Astro Configuration API Documentation
  * https://astro.build/config
  */
-export function defineConfig<
-		TDefaultLocale extends string,
-		const TLocales extends [
-			TDefaultLocale | { codes: [TDefaultLocale, ...Array<string>]; path: string },
-			...Locales,
-		],
-	>(config: AstroUserConfig<TDefaultLocale, TLocales>): AstroUserConfig<TDefaultLocale, TLocales>;
+export function defineConfig<const TLocales extends Locales>(
+	config: AstroUserDefineConfig<TLocales>,
+): AstroUserDefineConfig<TLocales>;
 
 /**
  * Use Astro to generate a fully resolved Vite config
diff --git a/packages/astro/src/config/index.ts b/packages/astro/src/config/index.ts
index 00f4197d8ccb..1faaa6a9654f 100644
--- a/packages/astro/src/config/index.ts
+++ b/packages/astro/src/config/index.ts
@@ -1,16 +1,12 @@
 import type { UserConfig as ViteUserConfig } from 'vite';
 import { Logger } from '../core/logger/core.js';
 import { createRouteManifest } from '../core/routing/index.js';
-import type { AstroInlineConfig, AstroUserConfig, Locales } from '../types/public/config.js';
+import type { AstroInlineConfig, AstroUserDefineConfig, Locales } from '../types/public/config.js';
 import { createDevelopmentManifest } from '../vite-plugin-astro-server/plugin.js';
 
-export function defineConfig<
-	TDefaultLocale extends string,
-	const TLocales extends [
-		TDefaultLocale | { codes: [TDefaultLocale, ...Array<string>]; path: string },
-		...Locales,
-	],
->(config: AstroUserConfig<TDefaultLocale, TLocales>) {
+export function defineConfig<const TLocales extends Locales>(
+	config: AstroUserDefineConfig<TLocales>,
+) {
 	return config;
 }
 
diff --git a/packages/astro/src/types/public/config.ts b/packages/astro/src/types/public/config.ts
index 5c7b0ba0f30a..a26388605a57 100644
--- a/packages/astro/src/types/public/config.ts
+++ b/packages/astro/src/types/public/config.ts
@@ -110,13 +110,9 @@ export interface ViteUserConfig extends OriginalViteUserConfig {
  * Astro User Config
  * Docs: https://docs.astro.build/reference/configuration-reference/
  */
-export interface AstroUserConfig<
-	TDefaultLocale extends string = never,
-	TLocales extends [
-		TDefaultLocale | { codes: [TDefaultLocale, ...Array<string>]; path: string },
-		...Locales,
-	] = never,
-> {
+export type AstroUserConfig = AstroUserDefineConfig<never>;
+
+export interface AstroUserDefineConfig<TLocales extends Locales = never> {
 	/**
 	 * @docs
 	 * @kind heading
@@ -1228,7 +1224,9 @@ export interface AstroUserConfig<
 		 *
 		 * No particular language format or syntax is enforced, but we suggest using lower-case and hyphens as needed (e.g. "es", "pt-br") for greatest compatibility.
 		 */
-		defaultLocale: [TDefaultLocale] extends [never] ? string : TDefaultLocale;
+		defaultLocale: [TLocales] extends [never]
+			? string
+			: NormalizeLocales<NoInfer<TLocales>>;
 		/**
 		 * @docs
 		 * @name i18n.locales
@@ -1275,7 +1273,10 @@ export interface AstroUserConfig<
 		fallback?: [TLocales] extends [never]
 			? Record<string, string>
 			: {
-					[Locale in NormalizeLocales<TLocales>]?: Exclude<NormalizeLocales<TLocales>, Locale>;
+					[Locale in NormalizeLocales<NoInfer<TLocales>>]?: Exclude<
+						NormalizeLocales<NoInfer<TLocales>>,
+						Locale
+					>;
 				};
 
 		/**
@@ -1464,7 +1465,7 @@ export interface AstroUserConfig<
 		 */
 		domains?: [TLocales] extends [never]
 			? Record<string, string>
-			: Partial<Record<NormalizeLocales<TLocales>, string>>;
+			: Partial<Record<NormalizeLocales<NoInfer<TLocales>>, string>>;
 	};
 
 	/** ! WARNING: SUBJECT TO CHANGE */

From 67b16d3124591eaf7da666854778a814da625673 Mon Sep 17 00:00:00 2001
From: Florian Lefebvre <contact@florian-lefebvre.dev>
Date: Wed, 16 Oct 2024 20:22:14 +0200
Subject: [PATCH 07/17] chore: changeset

---
 .changeset/forty-trains-notice.md | 4 +---
 1 file changed, 1 insertion(+), 3 deletions(-)

diff --git a/.changeset/forty-trains-notice.md b/.changeset/forty-trains-notice.md
index f722b7e1a7ae..ac6c51dd3914 100644
--- a/.changeset/forty-trains-notice.md
+++ b/.changeset/forty-trains-notice.md
@@ -4,6 +4,4 @@
 
 Makes `defineConfig` generic
 
-TypeScript will now provide feedback at the type level when using `defineConfig`. For example, it will make sure `i18n.locales` contains `i18n.defaultLocale`.
-
-This also makes the `AstroUserConfig` generic, but both changes are backward compatible.
+TypeScript will now provide feedback at the type level when using `defineConfig`. For example, it will make sure `i18n.defaultLocale` is one of the locales declared in `i18n.locales`

From 93e6393ee83729fa27ef20885ba4093f3aea4fa4 Mon Sep 17 00:00:00 2001
From: Florian Lefebvre <contact@florian-lefebvre.dev>
Date: Wed, 16 Oct 2024 20:42:38 +0200
Subject: [PATCH 08/17] feat: write tests

---
 packages/astro/config.d.ts                 |  2 +-
 packages/astro/src/config/index.ts         |  2 +-
 packages/astro/test/types/define-config.ts | 39 ++++++++++++++++++++++
 3 files changed, 41 insertions(+), 2 deletions(-)
 create mode 100644 packages/astro/test/types/define-config.ts

diff --git a/packages/astro/config.d.ts b/packages/astro/config.d.ts
index 36883c867d3d..7476a25ac0ee 100644
--- a/packages/astro/config.d.ts
+++ b/packages/astro/config.d.ts
@@ -13,7 +13,7 @@ type EnvField = typeof import('./dist/env/config.js').envField;
  * See the full Astro Configuration API Documentation
  * https://astro.build/config
  */
-export function defineConfig<const TLocales extends Locales>(
+export function defineConfig<const TLocales extends Locales = never>(
 	config: AstroUserDefineConfig<TLocales>,
 ): AstroUserDefineConfig<TLocales>;
 
diff --git a/packages/astro/src/config/index.ts b/packages/astro/src/config/index.ts
index 1faaa6a9654f..8de166477148 100644
--- a/packages/astro/src/config/index.ts
+++ b/packages/astro/src/config/index.ts
@@ -4,7 +4,7 @@ import { createRouteManifest } from '../core/routing/index.js';
 import type { AstroInlineConfig, AstroUserDefineConfig, Locales } from '../types/public/config.js';
 import { createDevelopmentManifest } from '../vite-plugin-astro-server/plugin.js';
 
-export function defineConfig<const TLocales extends Locales>(
+export function defineConfig<const TLocales extends Locales = never>(
 	config: AstroUserDefineConfig<TLocales>,
 ) {
 	return config;
diff --git a/packages/astro/test/types/define-config.ts b/packages/astro/test/types/define-config.ts
new file mode 100644
index 000000000000..ca91051c3e5d
--- /dev/null
+++ b/packages/astro/test/types/define-config.ts
@@ -0,0 +1,39 @@
+import { describe, it } from 'node:test';
+import { defineConfig } from '../../dist/config';
+import type { AstroUserDefineConfig } from '../../dist/types/public/config';
+import { expectTypeOf } from 'expect-type';
+
+describe('defineConfig()', () => {
+	it('Infers generics correctly', () => {
+		expectTypeOf(defineConfig({})).toEqualTypeOf<AstroUserDefineConfig<never>>();
+
+		expectTypeOf(
+			defineConfig({
+				i18n: {
+					locales: ['en'],
+					defaultLocale: 'en',
+				},
+			}),
+		).toEqualTypeOf<AstroUserDefineConfig<['en']>>();
+
+		expectTypeOf(
+			defineConfig({
+				i18n: {
+					locales: ['en', 'fr'],
+					defaultLocale: 'fr',
+				},
+			}),
+		).toEqualTypeOf<AstroUserDefineConfig<['en', 'fr']>>();
+
+		expectTypeOf(
+			defineConfig({
+				i18n: {
+					locales: ['en', { path: 'french', codes: ['fr', 'fr-FR'] }],
+					defaultLocale: 'en',
+				},
+			}),
+		).toEqualTypeOf<
+			AstroUserDefineConfig<['en', { readonly path: 'french'; readonly codes: ['fr', 'fr-FR'] }]>
+		>();
+	});
+});

From dd8d059d04b41d4d9cf42f8c07a093661d5586ce Mon Sep 17 00:00:00 2001
From: Florian Lefebvre <contact@florian-lefebvre.dev>
Date: Thu, 17 Oct 2024 14:39:36 +0200
Subject: [PATCH 09/17] feat: update docs

---
 packages/astro/src/types/public/config.ts | 27 +++++++++++------------
 1 file changed, 13 insertions(+), 14 deletions(-)

diff --git a/packages/astro/src/types/public/config.ts b/packages/astro/src/types/public/config.ts
index a26388605a57..eac95b19b197 100644
--- a/packages/astro/src/types/public/config.ts
+++ b/packages/astro/src/types/public/config.ts
@@ -1215,32 +1215,31 @@ export interface AstroUserDefineConfig<TLocales extends Locales = never> {
 	i18n?: {
 		/**
 		 * @docs
-		 * @name i18n.defaultLocale
-		 * @type {string}
+		 * @name i18n.locales
+		 * @type {Locales}
 		 * @version 3.5.0
 		 * @description
 		 *
-		 * The default locale of your website/application. This is a required field.
+		 * A list of all locales supported by the website. This is a required field.
 		 *
-		 * No particular language format or syntax is enforced, but we suggest using lower-case and hyphens as needed (e.g. "es", "pt-br") for greatest compatibility.
+		 * Languages can be listed either as individual codes (e.g. `['en', 'es', 'pt-br']`) or mapped to a shared `path` of codes (e.g.  `{ path: "english", codes: ["en", "en-US"]}`). These codes will be used to determine the URL structure of your deployed site.
+		 *
+		 * No particular language code format or syntax is enforced, but your project folders containing your content files must match exactly the `locales` items in the list. In the case of multiple `codes` pointing to a custom URL path prefix, store your content files in a folder with the same name as the `path` configured.
 		 */
-		defaultLocale: [TLocales] extends [never]
-			? string
-			: NormalizeLocales<NoInfer<TLocales>>;
+		locales: [TLocales] extends [never] ? Locales : TLocales;
+
 		/**
 		 * @docs
-		 * @name i18n.locales
-		 * @type {Locales}
+		 * @name i18n.defaultLocale
+		 * @type {string}
 		 * @version 3.5.0
 		 * @description
 		 *
-		 * A list of all locales supported by the website, including the `defaultLocale`. This is a required field.
+		 * The default locale of your website/application, that is one of the specified `locales`. This is a required field.
 		 *
-		 * Languages can be listed either as individual codes (e.g. `['en', 'es', 'pt-br']`) or mapped to a shared `path` of codes (e.g.  `{ path: "english", codes: ["en", "en-US"]}`). These codes will be used to determine the URL structure of your deployed site.
-		 *
-		 * No particular language code format or syntax is enforced, but your project folders containing your content files must match exactly the `locales` items in the list. In the case of multiple `codes` pointing to a custom URL path prefix, store your content files in a folder with the same name as the `path` configured.
+		 * No particular language format or syntax is enforced, but we suggest using lower-case and hyphens as needed (e.g. "es", "pt-br") for greatest compatibility.
 		 */
-		locales: [TLocales] extends [never] ? Locales : TLocales;
+		defaultLocale: [TLocales] extends [never] ? string : NormalizeLocales<NoInfer<TLocales>>;
 
 		/**
 		 * @docs

From eac4c72073d3b581e4b437482d6c90a7057eb2d9 Mon Sep 17 00:00:00 2001
From: Florian Lefebvre <contact@florian-lefebvre.dev>
Date: Thu, 17 Oct 2024 14:58:33 +0200
Subject: [PATCH 10/17] feat: improve config

---
 packages/astro/config.d.ts              | 44 -------------------------
 packages/astro/config.mjs               | 16 ---------
 packages/astro/package.json             |  7 +---
 packages/astro/src/config/entrypoint.ts | 19 +++++++++++
 packages/astro/src/config/index.ts      | 23 ++++++++++---
 packages/astro/src/env/config.ts        |  2 +-
 6 files changed, 40 insertions(+), 71 deletions(-)
 delete mode 100644 packages/astro/config.d.ts
 delete mode 100644 packages/astro/config.mjs
 create mode 100644 packages/astro/src/config/entrypoint.ts

diff --git a/packages/astro/config.d.ts b/packages/astro/config.d.ts
deleted file mode 100644
index 7476a25ac0ee..000000000000
--- a/packages/astro/config.d.ts
+++ /dev/null
@@ -1,44 +0,0 @@
-/// <reference path='./client.d.ts' />
-type ViteUserConfig = import('vite').UserConfig;
-type ViteUserConfigFn = import('vite').UserConfigFn;
-type Locales = import('./dist/types/public/config.js').Locales;
-type AstroUserDefineConfig<TLocales extends Locales> =
-	import('./dist/types/public/config.js').AstroUserDefineConfig<TLocales>;
-type AstroInlineConfig = import('./dist/types/public/config.js').AstroInlineConfig;
-type ImageServiceConfig = import('./dist/types/public/config.js').ImageServiceConfig;
-type SharpImageServiceConfig = import('./dist/assets/services/sharp.js').SharpImageServiceConfig;
-type EnvField = typeof import('./dist/env/config.js').envField;
-
-/**
- * See the full Astro Configuration API Documentation
- * https://astro.build/config
- */
-export function defineConfig<const TLocales extends Locales = never>(
-	config: AstroUserDefineConfig<TLocales>,
-): AstroUserDefineConfig<TLocales>;
-
-/**
- * Use Astro to generate a fully resolved Vite config
- */
-export function getViteConfig(
-	config: ViteUserConfig,
-	inlineAstroConfig?: AstroInlineConfig,
-): ViteUserConfigFn;
-
-/**
- * Return the configuration needed to use the Sharp-based image service
- */
-export function sharpImageService(config?: SharpImageServiceConfig): ImageServiceConfig;
-
-/**
- * Return the configuration needed to use the passthrough image service. This image services does not perform
- * any image transformations, and is mainly useful when your platform does not support other image services, or you are
- * not using Astro's built-in image processing.
- * See: https://docs.astro.build/en/guides/images/#configure-no-op-passthrough-service
- */
-export function passthroughImageService(): ImageServiceConfig;
-
-/**
- * Return a valid env field to use in this Astro config for `experimental.env.schema`.
- */
-export declare const envField: EnvField;
diff --git a/packages/astro/config.mjs b/packages/astro/config.mjs
deleted file mode 100644
index d117d806ed32..000000000000
--- a/packages/astro/config.mjs
+++ /dev/null
@@ -1,16 +0,0 @@
-export { defineConfig, getViteConfig } from './dist/config/index.js';
-export { envField } from './dist/env/config.js';
-
-export function sharpImageService(config = {}) {
-	return {
-		entrypoint: 'astro/assets/services/sharp',
-		config,
-	};
-}
-
-export function passthroughImageService() {
-	return {
-		entrypoint: 'astro/assets/services/noop',
-		config: {},
-	};
-}
diff --git a/packages/astro/package.json b/packages/astro/package.json
index 89f73b777ba5..fc26066d0528 100644
--- a/packages/astro/package.json
+++ b/packages/astro/package.json
@@ -46,10 +46,7 @@
     },
     "./compiler-runtime": "./dist/runtime/compiler/index.js",
     "./runtime/*": "./dist/runtime/*",
-    "./config": {
-      "types": "./config.d.ts",
-      "default": "./config.mjs"
-    },
+    "./config": "./dist/config/entrypoint.js",
     "./container": {
       "types": "./dist/container/index.d.ts",
       "default": "./dist/container/index.js"
@@ -93,8 +90,6 @@
     "types",
     "astro.js",
     "index.d.ts",
-    "config.d.ts",
-    "config.mjs",
     "zod.d.ts",
     "zod.mjs",
     "env.d.ts",
diff --git a/packages/astro/src/config/entrypoint.ts b/packages/astro/src/config/entrypoint.ts
new file mode 100644
index 000000000000..fff07f06c003
--- /dev/null
+++ b/packages/astro/src/config/entrypoint.ts
@@ -0,0 +1,19 @@
+import type { SharpImageServiceConfig } from '../assets/services/sharp.js';
+import type { ImageServiceConfig } from '../types/public/index.js';
+
+export { defineConfig, getViteConfig } from './index.js';
+export { envField } from '../env/config.js';
+
+export function sharpImageService(config: SharpImageServiceConfig = {}): ImageServiceConfig {
+	return {
+		entrypoint: 'astro/assets/services/sharp',
+		config,
+	};
+}
+
+export function passthroughImageService(): ImageServiceConfig {
+	return {
+		entrypoint: 'astro/assets/services/noop',
+		config: {},
+	};
+}
diff --git a/packages/astro/src/config/index.ts b/packages/astro/src/config/index.ts
index 8de166477148..2ded62a126cd 100644
--- a/packages/astro/src/config/index.ts
+++ b/packages/astro/src/config/index.ts
@@ -1,21 +1,28 @@
-import type { UserConfig as ViteUserConfig } from 'vite';
+import type { UserConfig as ViteUserConfig, UserConfigFn as ViteUserConfigFn } from 'vite';
 import { Logger } from '../core/logger/core.js';
 import { createRouteManifest } from '../core/routing/index.js';
 import type { AstroInlineConfig, AstroUserDefineConfig, Locales } from '../types/public/config.js';
 import { createDevelopmentManifest } from '../vite-plugin-astro-server/plugin.js';
 
+/**
+ * See the full Astro Configuration API Documentation
+ * https://astro.build/config
+ */
 export function defineConfig<const TLocales extends Locales = never>(
 	config: AstroUserDefineConfig<TLocales>,
 ) {
 	return config;
 }
 
+/**
+ * Use Astro to generate a fully resolved Vite config
+ */
 export function getViteConfig(
 	userViteConfig: ViteUserConfig,
 	inlineAstroConfig: AstroInlineConfig = {},
-) {
+): ViteUserConfigFn {
 	// Return an async Vite config getter which exposes a resolved `mode` and `command`
-	return async ({ mode, command }: { mode: 'dev'; command: 'serve' | 'build' }) => {
+	return async ({ mode, command }) => {
 		// Vite `command` is `serve | build`, but Astro uses `dev | build`
 		const cmd = command === 'serve' ? 'dev' : command;
 
@@ -54,7 +61,15 @@ export function getViteConfig(
 					astroContentListenPlugin({ settings, logger, fs }),
 				],
 			},
-			{ settings, logger, mode, sync: false, manifest, ssrManifest: devSSRManifest },
+			{
+				settings,
+				logger,
+				// TODO: can the custom mode solve that?
+				mode: mode as 'dev' | 'build',
+				sync: false,
+				manifest,
+				ssrManifest: devSSRManifest,
+			},
 		);
 		await runHookConfigDone({ settings, logger });
 		return mergeConfig(viteConfig, userViteConfig);
diff --git a/packages/astro/src/env/config.ts b/packages/astro/src/env/config.ts
index 629a1fe2e4e4..beb91b43b2c6 100644
--- a/packages/astro/src/env/config.ts
+++ b/packages/astro/src/env/config.ts
@@ -10,7 +10,7 @@ import type {
 } from './schema.js';
 
 /**
- * Return a valid env field to use in this Astro config for `experimental.env.schema`.
+ * Return a valid env field to use in this Astro config for `env.schema`.
  */
 export const envField = {
 	string: (options: StringFieldInput): StringField => ({

From c0e519d3ef8cdf06a91810fcc347aafb42893feb Mon Sep 17 00:00:00 2001
From: Florian Lefebvre <contact@florian-lefebvre.dev>
Date: Thu, 17 Oct 2024 14:59:44 +0200
Subject: [PATCH 11/17] fix: paths

---
 packages/astro/test/types/define-config.ts | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/packages/astro/test/types/define-config.ts b/packages/astro/test/types/define-config.ts
index ca91051c3e5d..3bd2ef22dc00 100644
--- a/packages/astro/test/types/define-config.ts
+++ b/packages/astro/test/types/define-config.ts
@@ -1,6 +1,6 @@
 import { describe, it } from 'node:test';
-import { defineConfig } from '../../dist/config';
-import type { AstroUserDefineConfig } from '../../dist/types/public/config';
+import { defineConfig } from '../../dist/config/index.js';
+import type { AstroUserDefineConfig } from '../../dist/types/public/config.js';
 import { expectTypeOf } from 'expect-type';
 
 describe('defineConfig()', () => {

From 4e9fdd6dce061a81f637a51e600164e058d3e6ec Mon Sep 17 00:00:00 2001
From: Florian Lefebvre <contact@florian-lefebvre.dev>
Date: Thu, 17 Oct 2024 15:09:28 +0200
Subject: [PATCH 12/17] Update .changeset/forty-trains-notice.md

---
 .changeset/forty-trains-notice.md | 4 +---
 1 file changed, 1 insertion(+), 3 deletions(-)

diff --git a/.changeset/forty-trains-notice.md b/.changeset/forty-trains-notice.md
index ac6c51dd3914..f77be4673689 100644
--- a/.changeset/forty-trains-notice.md
+++ b/.changeset/forty-trains-notice.md
@@ -2,6 +2,4 @@
 'astro': minor
 ---
 
-Makes `defineConfig` generic
-
-TypeScript will now provide feedback at the type level when using `defineConfig`. For example, it will make sure `i18n.defaultLocale` is one of the locales declared in `i18n.locales`
+Improves `defineConfig` type safety. TypeScript will now error if a group of related options do not have coherent types. For example, it will now error if `i18n.defaultLocale` is not one of the locales specified in `i18n.locales`

From db2d160ee95811fce2c9bcdddd02be5690fbba42 Mon Sep 17 00:00:00 2001
From: Florian Lefebvre <contact@florian-lefebvre.dev>
Date: Fri, 18 Oct 2024 15:15:44 +0200
Subject: [PATCH 13/17] feat: address reviews

---
 packages/astro/src/config/entrypoint.ts   | 11 +++++++++++
 packages/astro/src/types/public/config.ts |  1 +
 2 files changed, 12 insertions(+)

diff --git a/packages/astro/src/config/entrypoint.ts b/packages/astro/src/config/entrypoint.ts
index fff07f06c003..4951792d63ae 100644
--- a/packages/astro/src/config/entrypoint.ts
+++ b/packages/astro/src/config/entrypoint.ts
@@ -1,9 +1,14 @@
+// IMPORTANT: this file is the entrypoint for "astro/config". Keep it as light as possible!
+
 import type { SharpImageServiceConfig } from '../assets/services/sharp.js';
 import type { ImageServiceConfig } from '../types/public/index.js';
 
 export { defineConfig, getViteConfig } from './index.js';
 export { envField } from '../env/config.js';
 
+/**
+ * Return the configuration needed to use the Sharp-based image service
+ */
 export function sharpImageService(config: SharpImageServiceConfig = {}): ImageServiceConfig {
 	return {
 		entrypoint: 'astro/assets/services/sharp',
@@ -11,6 +16,12 @@ export function sharpImageService(config: SharpImageServiceConfig = {}): ImageSe
 	};
 }
 
+/**
+ * Return the configuration needed to use the passthrough image service. This image services does not perform
+ * any image transformations, and is mainly useful when your platform does not support other image services, or you are
+ * not using Astro's built-in image processing.
+ * See: https://docs.astro.build/en/guides/images/#configure-no-op-passthrough-service
+ */
 export function passthroughImageService(): ImageServiceConfig {
 	return {
 		entrypoint: 'astro/assets/services/noop',
diff --git a/packages/astro/src/types/public/config.ts b/packages/astro/src/types/public/config.ts
index f47560bb47cd..620899489087 100644
--- a/packages/astro/src/types/public/config.ts
+++ b/packages/astro/src/types/public/config.ts
@@ -112,6 +112,7 @@ export interface ViteUserConfig extends OriginalViteUserConfig {
  */
 export type AstroUserConfig = AstroUserDefineConfig<never>;
 
+/** @internal */
 export interface AstroUserDefineConfig<TLocales extends Locales = never> {
 	/**
 	 * @docs

From c6c98ffc5a50bb54738926dec540ff5c430784c3 Mon Sep 17 00:00:00 2001
From: Florian Lefebvre <contact@florian-lefebvre.dev>
Date: Fri, 18 Oct 2024 15:20:21 +0200
Subject: [PATCH 14/17] chore: improve types tests

---
 packages/astro/test/types/define-config.ts | 52 +++++++++++-----------
 1 file changed, 27 insertions(+), 25 deletions(-)

diff --git a/packages/astro/test/types/define-config.ts b/packages/astro/test/types/define-config.ts
index 3bd2ef22dc00..8a921abe58f8 100644
--- a/packages/astro/test/types/define-config.ts
+++ b/packages/astro/test/types/define-config.ts
@@ -5,35 +5,37 @@ import { expectTypeOf } from 'expect-type';
 
 describe('defineConfig()', () => {
 	it('Infers generics correctly', () => {
-		expectTypeOf(defineConfig({})).toEqualTypeOf<AstroUserDefineConfig<never>>();
+		const config_0 = defineConfig({});
+		expectTypeOf(config_0).toEqualTypeOf<AstroUserDefineConfig<never>>();
+		expectTypeOf(config_0.i18n!.defaultLocale).toEqualTypeOf<string>();
 
-		expectTypeOf(
-			defineConfig({
-				i18n: {
-					locales: ['en'],
-					defaultLocale: 'en',
-				},
-			}),
-		).toEqualTypeOf<AstroUserDefineConfig<['en']>>();
+		const config_1 = defineConfig({
+			i18n: {
+				locales: ['en'],
+				defaultLocale: 'en',
+			},
+		});
+		expectTypeOf(config_1).toEqualTypeOf<AstroUserDefineConfig<['en']>>();
+		expectTypeOf(config_1.i18n!.defaultLocale).toEqualTypeOf<'en'>();
 
-		expectTypeOf(
-			defineConfig({
-				i18n: {
-					locales: ['en', 'fr'],
-					defaultLocale: 'fr',
-				},
-			}),
-		).toEqualTypeOf<AstroUserDefineConfig<['en', 'fr']>>();
+		const config_2 = defineConfig({
+			i18n: {
+				locales: ['en', 'fr'],
+				defaultLocale: 'fr',
+			},
+		});
+		expectTypeOf(config_2).toEqualTypeOf<AstroUserDefineConfig<['en', 'fr']>>();
+		expectTypeOf(config_2.i18n!.defaultLocale).toEqualTypeOf<'en' | 'fr'>();
 
-		expectTypeOf(
-			defineConfig({
-				i18n: {
-					locales: ['en', { path: 'french', codes: ['fr', 'fr-FR'] }],
-					defaultLocale: 'en',
-				},
-			}),
-		).toEqualTypeOf<
+		const config_3 = defineConfig({
+			i18n: {
+				locales: ['en', { path: 'french', codes: ['fr', 'fr-FR'] }],
+				defaultLocale: 'en',
+			},
+		});
+		expectTypeOf(config_3).toEqualTypeOf<
 			AstroUserDefineConfig<['en', { readonly path: 'french'; readonly codes: ['fr', 'fr-FR'] }]>
 		>();
+		expectTypeOf(config_3.i18n!.defaultLocale).toEqualTypeOf<'en' | 'fr' | 'fr-FR'>();
 	});
 });

From 67bdf71705683d304eb2d8bff2ddb13facc22c7e Mon Sep 17 00:00:00 2001
From: Florian Lefebvre <contact@florian-lefebvre.dev>
Date: Mon, 21 Oct 2024 16:41:42 +0200
Subject: [PATCH 15/17] Update .changeset/forty-trains-notice.md

Co-authored-by: Sarah Rainsberger <sarah@rainsberger.ca>
---
 .changeset/forty-trains-notice.md | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/.changeset/forty-trains-notice.md b/.changeset/forty-trains-notice.md
index f77be4673689..29938198d6c8 100644
--- a/.changeset/forty-trains-notice.md
+++ b/.changeset/forty-trains-notice.md
@@ -2,4 +2,4 @@
 'astro': minor
 ---
 
-Improves `defineConfig` type safety. TypeScript will now error if a group of related options do not have coherent types. For example, it will now error if `i18n.defaultLocale` is not one of the locales specified in `i18n.locales`
+Improves `defineConfig` type safety. TypeScript will now error if a group of related configuration options do not have consistent types. For example, you will now see an error if your language set for `i18n.defaultLocale` is not one of the supported locales specified in `i18n.locales`.

From 7b6634048dfec7287e9984b0ec4f9f598c511b77 Mon Sep 17 00:00:00 2001
From: Florian Lefebvre <contact@florian-lefebvre.dev>
Date: Mon, 21 Oct 2024 16:53:36 +0200
Subject: [PATCH 16/17] feat: update error

---
 packages/astro/src/core/errors/errors-data.ts | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/packages/astro/src/core/errors/errors-data.ts b/packages/astro/src/core/errors/errors-data.ts
index 5ad2b939ed9f..fb93e6e9103e 100644
--- a/packages/astro/src/core/errors/errors-data.ts
+++ b/packages/astro/src/core/errors/errors-data.ts
@@ -1160,8 +1160,8 @@ export const UnhandledRejection = {
  * import { defineConfig } from 'astro'
  * export default defineConfig({
  *  i18n: {
- * 	 defaultLocale: 'en',
  * 	 locales: ['en', 'fr'],
+ * 	 defaultLocale: 'en',
  * 	},
  * })
  * ```

From 4dad4686d5f3c65e85c55c9f5a24bd850b966ae1 Mon Sep 17 00:00:00 2001
From: Florian Lefebvre <contact@florian-lefebvre.dev>
Date: Mon, 21 Oct 2024 18:06:29 +0200
Subject: [PATCH 17/17] feat: remove AstroUserDefineConfig

---
 packages/astro/src/config/index.ts         |  4 ++--
 packages/astro/src/types/public/config.ts  |  8 +++-----
 packages/astro/test/types/define-config.ts | 10 +++++-----
 3 files changed, 10 insertions(+), 12 deletions(-)

diff --git a/packages/astro/src/config/index.ts b/packages/astro/src/config/index.ts
index 0c92f48d32c1..62316377a8bb 100644
--- a/packages/astro/src/config/index.ts
+++ b/packages/astro/src/config/index.ts
@@ -1,7 +1,7 @@
 import type { UserConfig as ViteUserConfig, UserConfigFn as ViteUserConfigFn } from 'vite';
 import { Logger } from '../core/logger/core.js';
 import { createRouteManifest } from '../core/routing/index.js';
-import type { AstroInlineConfig, AstroUserDefineConfig, Locales } from '../types/public/config.js';
+import type { AstroInlineConfig, AstroUserConfig, Locales } from '../types/public/config.js';
 import { createDevelopmentManifest } from '../vite-plugin-astro-server/plugin.js';
 
 /**
@@ -9,7 +9,7 @@ import { createDevelopmentManifest } from '../vite-plugin-astro-server/plugin.js
  * https://astro.build/config
  */
 export function defineConfig<const TLocales extends Locales = never>(
-	config: AstroUserDefineConfig<TLocales>,
+	config: AstroUserConfig<TLocales>,
 ) {
 	return config;
 }
diff --git a/packages/astro/src/types/public/config.ts b/packages/astro/src/types/public/config.ts
index 620899489087..1e24f419408e 100644
--- a/packages/astro/src/types/public/config.ts
+++ b/packages/astro/src/types/public/config.ts
@@ -109,11 +109,9 @@ export interface ViteUserConfig extends OriginalViteUserConfig {
 /**
  * Astro User Config
  * Docs: https://docs.astro.build/reference/configuration-reference/
- */
-export type AstroUserConfig = AstroUserDefineConfig<never>;
-
-/** @internal */
-export interface AstroUserDefineConfig<TLocales extends Locales = never> {
+ * 
+ * Generics do not follow semver and may change at any time.
+ */ export interface AstroUserConfig<TLocales extends Locales = never> {
 	/**
 	 * @docs
 	 * @kind heading
diff --git a/packages/astro/test/types/define-config.ts b/packages/astro/test/types/define-config.ts
index 8a921abe58f8..9015694e2a9c 100644
--- a/packages/astro/test/types/define-config.ts
+++ b/packages/astro/test/types/define-config.ts
@@ -1,12 +1,12 @@
 import { describe, it } from 'node:test';
 import { defineConfig } from '../../dist/config/index.js';
-import type { AstroUserDefineConfig } from '../../dist/types/public/config.js';
+import type { AstroUserConfig } from '../../dist/types/public/index.js';
 import { expectTypeOf } from 'expect-type';
 
 describe('defineConfig()', () => {
 	it('Infers generics correctly', () => {
 		const config_0 = defineConfig({});
-		expectTypeOf(config_0).toEqualTypeOf<AstroUserDefineConfig<never>>();
+		expectTypeOf(config_0).toEqualTypeOf<AstroUserConfig<never>>();
 		expectTypeOf(config_0.i18n!.defaultLocale).toEqualTypeOf<string>();
 
 		const config_1 = defineConfig({
@@ -15,7 +15,7 @@ describe('defineConfig()', () => {
 				defaultLocale: 'en',
 			},
 		});
-		expectTypeOf(config_1).toEqualTypeOf<AstroUserDefineConfig<['en']>>();
+		expectTypeOf(config_1).toEqualTypeOf<AstroUserConfig<['en']>>();
 		expectTypeOf(config_1.i18n!.defaultLocale).toEqualTypeOf<'en'>();
 
 		const config_2 = defineConfig({
@@ -24,7 +24,7 @@ describe('defineConfig()', () => {
 				defaultLocale: 'fr',
 			},
 		});
-		expectTypeOf(config_2).toEqualTypeOf<AstroUserDefineConfig<['en', 'fr']>>();
+		expectTypeOf(config_2).toEqualTypeOf<AstroUserConfig<['en', 'fr']>>();
 		expectTypeOf(config_2.i18n!.defaultLocale).toEqualTypeOf<'en' | 'fr'>();
 
 		const config_3 = defineConfig({
@@ -34,7 +34,7 @@ describe('defineConfig()', () => {
 			},
 		});
 		expectTypeOf(config_3).toEqualTypeOf<
-			AstroUserDefineConfig<['en', { readonly path: 'french'; readonly codes: ['fr', 'fr-FR'] }]>
+			AstroUserConfig<['en', { readonly path: 'french'; readonly codes: ['fr', 'fr-FR'] }]>
 		>();
 		expectTypeOf(config_3.i18n!.defaultLocale).toEqualTypeOf<'en' | 'fr' | 'fr-FR'>();
 	});