Add new solution to 29.5 without using Pick

src/06-challenges/29.5-pick.solution2.ts

@@ -0,0 +1,44 @@
+import { expect, it } from "vitest";
+import { Equal, Expect } from "../helpers/type-utils";
+
+const pick = <TObj, TPicked extends keyof TObj>(
+  obj: TObj,
+  picked: Array<TPicked>
+) => {
+  return picked.reduce((acc, key) => {
+    acc[key] = obj[key];
+    return acc;
+  }, {} as {[PickedKey in TPicked]: TObj[PickedKey]});
+};
+
+it("Should pick the keys from the object", () => {
+  const result = pick(
+    {
+      a: 1,
+      b: 2,
+      c: 3,
+      d: true
+    },
+    ["a", "b", "d"]
+  );
+
+  expect(result).toEqual({ a: 1, b: 2 });
+
+  type test = Expect<Equal<typeof result, { a: number; b: number, d: boolean }>>;
+});
+
+it("Should not allow you to pass keys which do not exist in the object", () => {
+  pick(
+    {
+      a: 1,
+      b: 2,
+      c: 3,
+    },
+    [
+      "a",
+      "b",
+      // @ts-expect-error
+      "d",
+    ]
+  );
+});