From 4947eb095862baa9a7da939e77cadd2b1233d5b5 Mon Sep 17 00:00:00 2001
From: Luiz Ferraz <luiz@lferraz.com>
Date: Sat, 27 Apr 2024 19:46:36 -0300
Subject: [PATCH] fix: Simplify emitted declarations for dependent integrations

---
 .changeset/gorgeous-nails-cry.md       | 46 ++++++++++++++++++++++++++
 package/src/core/define-integration.ts |  3 +-
 package/src/core/with-plugins.ts       | 11 ++----
 3 files changed, 51 insertions(+), 9 deletions(-)
 create mode 100644 .changeset/gorgeous-nails-cry.md

diff --git a/.changeset/gorgeous-nails-cry.md b/.changeset/gorgeous-nails-cry.md
new file mode 100644
index 00000000..87380f45
--- /dev/null
+++ b/.changeset/gorgeous-nails-cry.md
@@ -0,0 +1,46 @@
+---
+"astro-integration-kit": patch
+---
+
+Simplify emitted declarations for dependent integrations.
+
+Previoysly an integration using AIK and publishing to NPM with their type declarations would generate a type like this:
+
+```ts
+declare const _default: (options?: undefined) => astro.AstroIntegration & {
+  hooks: {
+    "astro:config:setup": (params: {
+      config: astro.AstroConfig;
+      command: "dev" | "build" | "preview";
+      isRestart: boolean;
+      updateConfig: (
+        newConfig: DeepPartial<astro.AstroConfig>
+      ) => astro.AstroConfig;
+      addRenderer: (renderer: astro.AstroRenderer) => void;
+      addWatchFile: (path: string | URL) => void;
+      injectScript: (stage: astro.InjectedScriptStage, content: string) => void;
+      injectRoute: (injectRoute: astro.InjectedRoute) => void;
+      addClientDirective: (directive: astro.ClientDirectiveConfig) => void;
+      addDevOverlayPlugin: (entrypoint: string) => void;
+      addDevToolbarApp: (entrypoint: string | astro.DevToolbarAppEntry) => void;
+      addMiddleware: (mid: astro.AstroIntegrationMiddleware) => void;
+      logger: astro.AstroIntegrationLogger;
+    }) => void;
+  };
+  addExtraPage: (page: string) => void;
+};
+```
+
+Such inlining of the Astro hook parameter types not only makes your published package include unnecessary code, but can also make it fail to compile if you use a hook that inlines a reference to a transitive dependency:
+
+```
+error TS2742: The inferred type of 'default' cannot be named without a reference to '.pnpm/vite@5.2.10_@types+node@20.12.7/node_modules/vite'. This is likely not portable. A type annotation is necessary.
+```
+
+Now, the same integration will emit the following simplified declaration, without inlining any of the AstroHooks types:
+
+```ts
+declare const _default: (options?: undefined) => astro.AstroIntegration & {
+  addExtraPage: (page: string) => void;
+};
+```
diff --git a/package/src/core/define-integration.ts b/package/src/core/define-integration.ts
index e63ab943..92783432 100644
--- a/package/src/core/define-integration.ts
+++ b/package/src/core/define-integration.ts
@@ -2,6 +2,7 @@ import type { AstroIntegration } from "astro";
 import { AstroError } from "astro/errors";
 import { z } from "astro/zod";
 import { errorMap } from "../internal/error-map.js";
+import type { Prettify } from "../internal/types.ts";
 
 type AstroIntegrationSetupFn<Options extends z.ZodTypeAny> = (params: {
 	name: string;
@@ -46,7 +47,7 @@ export const defineIntegration = <
 		: undefined extends z.input<TOptionsSchema>
 		  ? [options?: z.input<TOptionsSchema>]
 		  : [options: z.input<TOptionsSchema>]
-) => AstroIntegration & ReturnType<TSetup>) => {
+) => AstroIntegration & Prettify<Omit<ReturnType<TSetup>, keyof AstroIntegration>>) => {
 	return (...args): AstroIntegration & ReturnType<TSetup> => {
 		const parsedOptions = (optionsSchema ?? z.never().optional()).safeParse(
 			args[0],
diff --git a/package/src/core/with-plugins.ts b/package/src/core/with-plugins.ts
index db256234..8c5681d9 100644
--- a/package/src/core/with-plugins.ts
+++ b/package/src/core/with-plugins.ts
@@ -1,5 +1,5 @@
 import type { AstroIntegration } from "astro";
-import type { NonEmptyArray } from "../internal/types.js";
+import type { NonEmptyArray, Prettify } from "../internal/types.js";
 import type {
 	AddedParam,
 	AnyPlugin,
@@ -14,12 +14,7 @@ type WithPluginsParams<TPlugins extends NonEmptyArray<AnyPlugin>> = {
 	hooks: ExtendedHooks<TPlugins>;
 };
 
-type WithPluginsReturn<Extensions> = Omit<
-	Extensions,
-	"name" | "plugins" | "hooks"
-> & {
-	hooks: AstroIntegration["hooks"];
-};
+export type WithPluginsReturn<Extensions> = Extensions & Omit<AstroIntegration, 'name'>;
 
 /**
  * Allows to extend hooks with custom parameters. Only used for advanced use-cases.
@@ -34,7 +29,7 @@ export const withPlugins = <
 	Extensions extends Record<any, unknown>,
 >(
 	options: WithPluginsParams<TPlugins> & Extensions,
-): WithPluginsReturn<Extensions> => {
+): WithPluginsReturn<Prettify<Omit<Extensions, keyof WithPluginsParams<any>>>> => {
 	const {
 		name,
 		plugins,