vitest-environment-firestore-emulator/src/index.ts

This package contains a [`vitest`](https://vitest.dev/) environment for setup `@firestore-emulator/server`.

import {
  FirestoreServer,
  type FirestoreState,
} from "@firestore-emulator/server";
import { findFreePorts } from "find-free-ports";
import type { Environment } from "vitest/environments";
import { builtinEnvironments } from "vitest/environments";

declare global {
  var emulator: {
    host: string;
    port: number;
    state: FirestoreState;
  };
}

export interface Options {
  "firestore-emulator"?: {
    baseEnv?: keyof typeof builtinEnvironments;
  };
}

export default {
  name: "firestore-emulator",
  async setup(global: typeof globalThis, options: Options = {}) {
    const supper = await builtinEnvironments[
      options["firestore-emulator"]?.baseEnv ?? "node"
    ].setup(global, options);
    const server = new FirestoreServer();

    let tryCount = 0;
    while (tryCount < 50) {
      const [port] = await findFreePorts(1);
      if (!port) throw new Error("Could not find a free port");
      try {
        await server.start(port);
        global.emulator = {
          host: `0.0.0.0:${port}`,
          port,
          state: server.state,
        };
        return {
          async teardown() {
            server.stop();
            await supper.teardown(global);
          },
        };
      } catch (err) {
        if (!(err instanceof Error)) throw err;
        if (!err.message.startsWith("No address added out of total")) throw err;
      }
      tryCount++;
    }
    throw new Error("Could not find a free port");
  },
  transformMode: "ssr",
} satisfies Environment;