Testing

Popii ships a testing sub-package that lets you unit-test commands without a Discord connection or live bot. Tests run in Bun's built-in test runner.

Setup

// No extra install needed — it's included with popii
import { createTestClient, runCommand } from "popii/testing";
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Testing a command

// test/commands/ping.test.ts
import { describe, it, expect } from "bun:test";
import { createTestClient, runCommand } from "popii/testing";
import pingCommand from "../../src/commands/ping";

describe("/ping", () => {
  it("replies with Pong!", async () => {
    const client = createTestClient();
    const result = await runCommand(pingCommand, { client });

    expect(result.replies[0].content).toContain("Pong!");
  });
});
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Providing options

import { runCommand, mockOptions } from "popii/testing";
import greetCommand from "../../src/commands/greet";

it("greets the specified user", async () => {
  const client = createTestClient();
  const result = await runCommand(greetCommand, {
    client,
    options: mockOptions({ user: { id: "123", username: "Alice" } })
  });

  expect(result.replies[0].content).toContain("Alice");
});
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Mocking locals and state

it("rejects when not premium", async () => {
  const client = createTestClient();
  const result = await runCommand(premiumCommand, {
    client,
    locals: { dbUser: { premium: false, balance: 0 } }
  });

  expect(result.replies[0].ephemeral).toBe(true);
  expect(result.replies[0].content).toContain("Premium users only");
});
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Testing with middleware

Pass an array of middlewares to run the full pipeline:

import { middleware } from "popii";
import myMiddleware from "../../src/middlewares/02-load-user";

it("loads the user before running the command", async () => {
  const client = createTestClient();
  const result = await runCommand(someCommand, {
    client,
    middlewares: [myMiddleware],
    locals: {}
  });

  expect(result.replies[0].content).toBeDefined();
});
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Inspecting deferred replies

it("defers and then replies", async () => {
  const client = createTestClient();
  const result = await runCommand(slowCommand, { client });

  expect(result.deferred).toBe(true);
  expect(result.replies[0]).toBeDefined();
});
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Running tests

bun test                         # run all tests
bun test test/commands/ping.test.ts   # run a specific file
bun test --watch                 # re-run on file changes
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Or use the CLI generator to scaffold a test file:

popii g test ping
# creates test/commands/ping.test.ts with boilerplate
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