bun.sh/test/bundler/resolver/cache-runtime.test.ts

import { describe, expect, test } from "bun:test";
import { promises as fs } from "fs";
import { tempDir } from "harness";
import * as path from "path";

// These tests verify that the resolver properly invalidates cache at runtime
// when using require() across file system changes within the same process.
// These test the same cache invalidation logic as the Bun.build tests but for runtime require().

describe.concurrent("runtime cache invalidation", () => {
  test("directory with index.js deleted then recreated", async () => {
    using dir = tempDir("runtime-cache-index-js", {
      "subdir/index.js": `module.exports = { value: 42 };`,
    });

    const subdirPath = path.join(String(dir), "subdir");
    const requirePath = subdirPath;

    // Require 1: Should succeed
    const result1 = require(requirePath);
    expect(result1.value).toBe(42);

    // Clear require cache
    const resolvedPath = require.resolve(requirePath);
    delete require.cache[resolvedPath];

    // Delete directory
    await fs.rm(subdirPath, { recursive: true });

    // Require 2: Should fail
    let require2Failed = false;
    try {
      require(requirePath);
    } catch (e) {
      require2Failed = true;
    }
    expect(require2Failed).toBe(true);

    // Recreate directory with new content
    await fs.mkdir(subdirPath);
    await fs.writeFile(path.join(subdirPath, "index.js"), `module.exports = { value: 99 };`);

    // Require 3: Should succeed with new value
    const result3 = require(requirePath);
    expect(result3.value).toBe(99);
  });

  test("direct file deleted then recreated", async () => {
    using dir = tempDir("runtime-cache-direct-file", {
      "config.js": `module.exports = { version: 1 };`,
    });

    const configPath = path.join(String(dir), "config.js");

    // Require 1: Should succeed
    const result1 = require(configPath);
    expect(result1.version).toBe(1);

    // Clear require cache
    const resolvedPath = require.resolve(configPath);
    delete require.cache[resolvedPath];

    // Delete file
    await fs.rm(configPath);

    // Require 2: Should fail
    let require2Failed = false;
    try {
      require(configPath);
    } catch (e) {
      require2Failed = true;
    }
    expect(require2Failed).toBe(true);

    // Recreate file with new content
    await fs.writeFile(configPath, `module.exports = { version: 2 };`);

    // Require 3: Should succeed with new value
    const result3 = require(configPath);
    expect(result3.version).toBe(2);
  });

  test("nested directory deleted then recreated", async () => {
    using dir = tempDir("runtime-cache-nested", {
      "deep/nested/module.js": `module.exports = { value: "original" };`,
    });

    const modulePath = path.join(String(dir), "deep", "nested", "module.js");
    const deepPath = path.join(String(dir), "deep");

    // Require 1: Should succeed
    const result1 = require(modulePath);
    expect(result1.value).toBe("original");

    // Clear require cache
    delete require.cache[require.resolve(modulePath)];

    // Delete parent directory
    await fs.rm(deepPath, { recursive: true });

    // Require 2: Should fail
    let require2Failed = false;
    try {
      require(modulePath);
    } catch (e) {
      require2Failed = true;
    }
    expect(require2Failed).toBe(true);

    // Recreate directory structure
    const nestedPath = path.join(deepPath, "nested");
    await fs.mkdir(deepPath);
    await fs.mkdir(nestedPath);
    await fs.writeFile(path.join(nestedPath, "module.js"), `module.exports = { value: "recreated" };`);

    // Require 3: Should succeed
    const result3 = require(modulePath);
    expect(result3.value).toBe("recreated");
  });
});