/**
 * Tree-shake guard — verify subpaths don't drag unrelated modules.
 */
import { readFile } from "node:fs/promises";
import { dirname, resolve } from "node:path";
import { fileURLToPath } from "node:url";
import { describe, expect, it } from "../src/runner/index.js";

const here = dirname(fileURLToPath(import.meta.url));
const distRoot = resolve(here, "..", "dist");

async function distExists(): Promise<boolean> {
    try {
        await readFile(resolve(distRoot, "index.js"), "utf8");
        return true;
    } catch {
        return false;
    }
}

async function readDist(rel: string): Promise<string> {
    return readFile(resolve(distRoot, rel), "utf8");
}

describe("tree-shake guards", () => {
    it("matchers subpath does not pull renderComponent", {
        timeout: 10000,
    }, async () => {
        if (!(await distExists())) return;
        const text = await readDist("matchers/matchers.js");
        expect(text).not.toMatch(/function\s+renderComponent\b/);
        expect(text).not.toMatch(/class\s+RenderError\b/);
    });

    it("user/setup-user does not pull jest-dom matchers", {
        timeout: 10000,
    }, async () => {
        if (!(await distExists())) return;
        const text = await readDist("user/setup-user.js");
        expect(text).not.toMatch(/toBeInTheDocument/);
        expect(text).not.toMatch(/jest-dom/);
    });

    it("polyfills subpath has no functional surface", {
        timeout: 10000,
    }, async () => {
        if (!(await distExists())) return;
        const text = await readDist("setup/polyfills.js");
        expect(text).not.toMatch(/export\s+(?:const|function|class)/);
    });
});