add solution day 05

05/index.ts

@@ -0,0 +1,37 @@
+
+import { Expect, Equal } from 'type-testing';
+
+type SantasList<Bads extends readonly unknown[], Goods extends readonly unknown[]> = [...Bads, ...Goods];
+
+// ------------------- Test section ---------------------
+
+const bads = ['tommy', 'trash'] as const;
+const goods = ['bash', 'tru'] as const;
+
+type test_0_actual = SantasList<typeof bads, typeof goods>;
+//   ^?
+type test_0_expected = ['tommy', 'trash', 'bash', 'tru'];
+type test_0 = Expect<Equal<test_0_actual, test_0_expected>>;
+
+type test_1_actual = SantasList<[], []>;
+//   ^?
+type test_1_expected = [];
+type test_1 = Expect<Equal<test_1_actual, test_1_expected>>;
+
+type test_2_actual = SantasList<[], ['trash']>;
+//   ^?
+type test_2_expected = ['trash'];
+type test_2 = Expect<Equal<test_2_actual, test_2_expected>>;
+
+type test_3_actual = SantasList<['john'], ['ashley', 'elliot', 'ziltoid']>;
+//   ^?
+type test_3_expected = ['john', 'ashley', 'elliot', 'ziltoid'];
+type test_3 = Expect<Equal<test_3_actual, test_3_expected>>;
+
+type test_4_actual = SantasList<['1', 2, '3'], [false, boolean, '4', ['nested']]>;
+//   ^?
+type test_4_expected = ['1', 2, '3', false, boolean, '4', ['nested']];
+type test_4 = Expect<Equal<test_4_actual, test_4_expected>>;
+
+// @ts-expect-error allow only array
+type test_error_0 = SantasList<null, undefined>;