chore(backend): Add getAuth() type helper tests

.changeset/ten-shirts-double.md

@@ -0,0 +1,2 @@
+---
+---

packages/backend/src/tokens/__tests__/types.test.ts

@@ -0,0 +1,26 @@
+import { expectTypeOf, test } from 'vitest';
+
+import type { GetAuthFn, MachineAuthObject, SessionAuthObject } from '../types';
+
+test('infers the correct AuthObject type for each accepted token type', () => {
+  const request = new Request('https://example.com');
+
+  // Across our SDKs, we have a getAuth() function
+  const getAuth: GetAuthFn<Request> = (_request: any, _options: any) => {
+    return {} as any;
+  };
+
+  // Session token by default
+  expectTypeOf(getAuth(request)).toEqualTypeOf<SessionAuthObject>();
+
+  // Individual token types
+  expectTypeOf(getAuth(request, { acceptsToken: 'session_token' })).toEqualTypeOf<SessionAuthObject>();
+  expectTypeOf(getAuth(request, { acceptsToken: 'api_key' })).toEqualTypeOf<MachineAuthObject<'api_key'>>();
+  expectTypeOf(getAuth(request, { acceptsToken: 'machine_token' })).toEqualTypeOf<MachineAuthObject<'machine_token'>>();
+  expectTypeOf(getAuth(request, { acceptsToken: 'oauth_token' })).toEqualTypeOf<MachineAuthObject<'oauth_token'>>();
+
+  // Array of token types
+  expectTypeOf(getAuth(request, { acceptsToken: ['session_token', 'oauth_token'] })).toEqualTypeOf<
+    SessionAuthObject | MachineAuthObject<'oauth_token'>
+  >();
+});

packages/backend/src/tokens/types.ts

@@ -163,8 +163,8 @@ export type InferAuthObjectFromTokenArray<
 > = SessionTokenType extends T[number]
   ? T[number] extends SessionTokenType
     ? SessionType
-    : SessionType | (MachineType & { tokenType: T[number] })
-  : MachineType & { tokenType: T[number] };
+    : SessionType | (MachineType & { tokenType: Exclude<T[number], SessionTokenType> })
+  : MachineType & { tokenType: Exclude<T[number], SessionTokenType> };
 
 /**
  * Infers auth object type from a single token type.
@@ -174,11 +174,11 @@ export type InferAuthObjectFromToken<
   T extends TokenType,
   SessionType extends AuthObject,
   MachineType extends AuthObject,
-> = T extends SessionTokenType ? SessionType : MachineType & { tokenType: T };
+> = T extends SessionTokenType ? SessionType : MachineType & { tokenType: Exclude<T, SessionTokenType> };
 
 export type SessionAuthObject = SignedInAuthObject | SignedOutAuthObject;
 export type MachineAuthObject<T extends TokenType> = (AuthenticatedMachineObject | UnauthenticatedMachineObject) & {
-  tokenType: T;
+  tokenType: Exclude<T, SessionTokenType>;
 };
 
 type AuthOptions = PendingSessionOptions & { acceptsToken?: AuthenticateRequestOptions['acceptsToken'] };

packages/backend/vitest.config.mts

@@ -3,6 +3,10 @@ import { defineConfig } from 'vitest/config';
 export default defineConfig({
   plugins: [],
   test: {
+    typecheck: {
+      enabled: true,
+      include: ['**/*.test.ts'],
+    },
     coverage: {
       provider: 'v8',
     },