Rework ID

Author: CarsonF

src/common/id-field.test.ts

@@ -0,0 +1,37 @@
+/* eslint-disable @seedcompany/no-unused-vars */
+import { test } from '@jest/globals';
+import type { User } from '../components/user';
+import { ID } from './id-field';
+
+test('only types here', () => undefined);
+
+const NameFromSelf: ID<'User'> = '' as ID<'User'>;
+const NameFromDB: ID<'User'> = '' as ID<'default::User'>;
+const NameFromInstance: ID<'User'> = '' as ID<User>;
+const NameFromStatic: ID<'User'> = '' as ID<typeof User>;
+
+const NameToSelf: ID<'User'> = '' as ID<'User'>;
+const NameToDB: ID<'default::User'> = '' as ID<'User'>;
+const NameToInstance: ID<User> = '' as ID<'User'>;
+const NameToStatic: ID<typeof User> = '' as ID<'User'>;
+
+const NameFromAny: ID<'User'> = '' as ID;
+const NameToAny: ID = '' as ID<'User'>;
+
+const AnyStringWorks: ID<'asdf'> = '' as ID;
+const AnyObjectWorks: ID<Date> = '' as ID;
+
+// @ts-expect-error this should be blocked
+const UserIncompatibleDifferent: ID<'User'> = '' as ID<'Location'>;
+// @ts-expect-error this should be blocked
+const UserIncompatibleDifferent2: ID<'Location'> = '' as ID<'User'>;
+
+const SubclassesAreCompatible: ID<'Engagement'> =
+  '' as ID<'LanguageEngagement'>;
+// @ts-expect-error this should be blocked
+const InterfaceIsNotDirectlyCompatibleWithConcrete: ID<'LanguageEngagement'> =
+  '' as ID<'Engagement'>;
+const ButCanBeTypeCastAsInterfaceOverlapsConcrete =
+  '' as ID<'Engagement'> as ID<'LanguageEngagement'>;
+// @ts-expect-error this should be blocked
+const IndependentTypesCannotBeTypeCast = '' as ID<'Engagement'> as ID<'User'>;

src/common/id-field.ts

@@ -1,7 +1,12 @@
 import { applyDecorators } from '@nestjs/common';
 import { Field, FieldOptions, ID as IDType } from '@nestjs/graphql';
 import { ValidationOptions } from 'class-validator';
-import { Opaque } from 'type-fest';
+import { IsAny, IsNever, Tagged } from 'type-fest';
+import type {
+  AllResourceDBNames,
+  ResourceName,
+  ResourceNameLike,
+} from '~/core';
 import { IsId } from './validators';
 
 export const IdField = ({
@@ -13,11 +18,26 @@ export const IdField = ({
     IsId(validation),
   );
 
-export type ID = Opaque<string, 'ID'>;
-
 export const isIdLike = (value: unknown): value is ID =>
   typeof value === 'string';
 
-declare const ref: unique symbol;
-/** An ID for a specific thing */
-export type IdOf<T> = ID & { readonly [ref]: T };
+export type ID<Kind extends IDKindLike = any> = Tagged<string, 'ID'> &
+  IDTo<IDTag<Kind>>;
+
+/** @deprecated Use {@link ID} */
+export type IdOf<Kind extends IDKindLike> = ID<Kind>;
+
+declare const IDTo: unique symbol;
+// eslint-disable-next-line @typescript-eslint/consistent-type-definitions
+type IDTo<T> = { readonly [IDTo]: T };
+
+// Normalize resource name if possible, otherwise use input directly
+type IDTag<Kind> = IsAny<Kind> extends true
+  ? any // continue to allow ID<any> to be assignable to any ID
+  : ResourceName<Kind, true> extends infer Normalized
+  ? IsNever<Normalized> extends false
+    ? Normalized
+    : Kind
+  : never;
+
+type IDKindLike = ResourceNameLike | AllResourceDBNames | object;