From 2e7c82ff5720060fa14641cdbfa24101d6bee933 Mon Sep 17 00:00:00 2001
From: Bereket Engida <bekacru@gmail.com>
Date: Thu, 12 Sep 2024 14:29:54 +0300
Subject: [PATCH] fix: session inference

---
 .../better-auth/src/client/client.test.ts     |  5 ++++-
 .../better-auth/src/client/session-atom.ts    | 15 ++++++-------
 .../better-auth/src/client/test-plugin.ts     |  2 +-
 packages/better-auth/src/types/helper.ts      | 22 +++++++++++++++++++
 todo.md                                       |  1 +
 5 files changed, 35 insertions(+), 10 deletions(-)

diff --git a/packages/better-auth/src/client/client.test.ts b/packages/better-auth/src/client/client.test.ts
index 32841b7f09..ac88132013 100644
--- a/packages/better-auth/src/client/client.test.ts
+++ b/packages/better-auth/src/client/client.test.ts
@@ -9,6 +9,7 @@ import type { Ref } from "vue";
 import type { ReadableAtom } from "nanostores";
 import type { Session } from "../adapters/schema";
 import { BetterFetchError } from "@better-fetch/fetch";
+import { twoFactorClient } from "../plugins";
 
 describe("run time proxy", async () => {
 	it("proxy api should be called", async () => {
@@ -160,7 +161,7 @@ describe("type", () => {
 
 	it("should infer session", () => {
 		const client = createSolidClient({
-			plugins: [testClientPlugin(), testClientPlugin2()],
+			plugins: [testClientPlugin(), testClientPlugin2(), twoFactorClient()],
 			baseURL: "http://localhost:3000",
 		});
 		const $infer = client.$infer;
@@ -182,6 +183,8 @@ describe("type", () => {
 			testField?: string | undefined;
 			testField2?: number | undefined;
 			testField4: string;
+			twoFactorEnabled?: boolean | undefined;
+			twoFactorSecret?: string | undefined;
 		}>();
 	});
 });
diff --git a/packages/better-auth/src/client/session-atom.ts b/packages/better-auth/src/client/session-atom.ts
index e117137e53..de0d30e893 100644
--- a/packages/better-auth/src/client/session-atom.ts
+++ b/packages/better-auth/src/client/session-atom.ts
@@ -12,15 +12,15 @@ export function getSessionAtom<Option extends ClientOptions>(
 ) {
 	type Plugins = Option["plugins"] extends Array<AuthClientPlugin>
 		? Array<
-				UnionToIntersection<
-					Option["plugins"] extends Array<infer Pl>
-						? Pl extends AuthClientPlugin
-							? Pl["$InferServerPlugin"] extends BetterAuthPlugin
-								? Pl["$InferServerPlugin"]
+				Option["plugins"][number] extends infer T
+					? T extends AuthClientPlugin
+						? T["$InferServerPlugin"] extends infer U
+							? U extends BetterAuthPlugin
+								? U
 								: never
 							: never
 						: never
-				>
+					: never
 			>
 		: never;
 
@@ -33,9 +33,7 @@ export function getSessionAtom<Option extends ClientOptions>(
 		};
 	};
 
-	//@ts-expect-error
 	type UserWithAdditionalFields = InferUser<Auth["options"]>;
-	//@ts-expect-error
 	type SessionWithAdditionalFields = InferSession<Auth["options"]>;
 	const $signal = atom<boolean>(false);
 	const session = useAuthQuery<{
@@ -50,6 +48,7 @@ export function getSessionAtom<Option extends ClientOptions>(
 		$infer: {} as {
 			session: Prettify<SessionWithAdditionalFields>;
 			user: Prettify<UserWithAdditionalFields>;
+			pl: Plugins;
 		},
 	};
 }
diff --git a/packages/better-auth/src/client/test-plugin.ts b/packages/better-auth/src/client/test-plugin.ts
index 7093d012e8..bbc5d4e0db 100644
--- a/packages/better-auth/src/client/test-plugin.ts
+++ b/packages/better-auth/src/client/test-plugin.ts
@@ -59,7 +59,7 @@ export const testClientPlugin = () => {
 		return testValue++;
 	});
 	return {
-		id: "test",
+		id: "test" as const,
 		getActions($fetch) {
 			return {
 				setTestAtom(value: boolean) {
diff --git a/packages/better-auth/src/types/helper.ts b/packages/better-auth/src/types/helper.ts
index c686cf110f..89d9d630e9 100644
--- a/packages/better-auth/src/types/helper.ts
+++ b/packages/better-auth/src/types/helper.ts
@@ -30,3 +30,25 @@ export type RequiredKeysOf<BaseType extends object> = Exclude<
 export type HasRequiredKeys<BaseType extends object> =
 	RequiredKeysOf<BaseType> extends never ? false : true;
 export type WithoutEmpty<T> = T extends T ? ({} extends T ? never : T) : never;
+
+type LastOf<T> = UnionToIntersection<
+	T extends any ? () => T : never
+> extends () => infer R
+	? R
+	: never;
+
+type Push<T extends any[], V> = [...T, V];
+
+type TuplifyUnion<
+	T,
+	L = LastOf<T>,
+	N = [T] extends [never] ? true : false,
+> = true extends N ? [] : Push<TuplifyUnion<Exclude<T, L>>, L>;
+
+// The magic happens here!
+export type Tuple<
+	T,
+	A extends T[] = [],
+> = TuplifyUnion<T>["length"] extends A["length"]
+	? [...A]
+	: Tuple<T, [T, ...A]>;
diff --git a/todo.md b/todo.md
index 1009012184..6f5854b637 100644
--- a/todo.md
+++ b/todo.md
@@ -12,6 +12,7 @@
 [ ] allow enabling two factor automatically for users
 [ ] change the pg driver to https://www.npmjs.com/package/postgres (maybe)
 [ ] mention how users can get user and session types
+[ ] add a section about updating user and changing password
 
 
 ## Docs