Temporal Zod Deno Demo - Demonstrating Temporal.Instant validation and coercion

README.md

Temporal Zod Deno Demo

A demonstration of using temporal-polyfill and temporal-zod in a Deno TypeScript project, focusing on Temporal.Instant validation and coercion.

What This Demonstrates

This project shows how temporal-zod schemas can accept either:

• A Temporal.Instant instance
• An ISO 8601 timestamp string

...and automatically coerce both to a Temporal.Instant object.

Prerequisites

• Deno installed on your system

Running the Code

deno test

deno.json

{
  "imports": {
    "temporal-polyfill": "npm:temporal-polyfill@0.3.0",
    "temporal-zod": "npm:temporal-zod@0.5.0",
    "zod": "npm:zod@4.1.12"
  }
}

main.test.ts

import { describe, it, expect } from "vitest";
import { Temporal } from "temporal-polyfill";
import { z } from "zod";
import { zInstant } from "temporal-zod";

const EventSchema = z.object({
  name: z.string(),
  timestamp: zInstant,
});

type Event = z.infer<typeof EventSchema>;

function createEventWithInstant(): Event {
  return EventSchema.parse({
    name: "System Boot",
    timestamp: Temporal.Now.instant(),
  });
}

function createEventWithISOString(): Event {
  return EventSchema.parse({
    name: "User Login",
    timestamp: "2025-10-24T15:30:00Z",
  });
}

describe("Event creation with Temporal.Instant", () => {
  it("should create event with Temporal.Instant", () => {
    const event = createEventWithInstant();

    expect(event.name).toBe("System Boot");
    expect(event.timestamp).toBeInstanceOf(Temporal.Instant);
    expect(event.timestamp.toString()).toMatch(/^\d{4}-\d{2}-\d{2}T\d{2}:\d{2}:\d{2}(\.\d+)?Z$/);
  });

  it("should have correct type for timestamp", () => {
    const event = createEventWithInstant();

    expect(event.timestamp.constructor.name).toBe("Instant");
  });
});

describe("Event creation with ISO String", () => {
  it("should create event with ISO string and parse to Temporal.Instant", () => {
    const event = createEventWithISOString();

    expect(event.name).toBe("User Login");
    expect(event.timestamp).toBeInstanceOf(Temporal.Instant);
    expect(event.timestamp.toString()).toBe("2025-10-24T15:30:00Z");
  });

  it("should have correct type for timestamp", () => {
    const event = createEventWithISOString();

    expect(event.timestamp.constructor.name).toBe("Instant");
  });
});

A subset of https://gist.github.com/kevinmichaelchen/4f48dd7da6e453d6d73adfe49750340b