Module-Rust/server/test/checkBundle.test.js

// The bundle check, checked.
//
// `scripts/checkBundle.js` exists because of a failure this module has not had
// and does not intend to: Module-uo's v1.0.0 shipped without `server/commands/`
// and died at the register stage on the operator's box. A check written in
// response to one bug is worth exactly as much as its coverage of that bug, so
// the first two tests below are that bug, in both modes — a list that has stopped
// covering what the entry point reaches, and a tarball with the file missing from
// it — and the third pair is this module's own version of it, a runtime
// dependency declared and not packed.
//
// **Every fixture is a template literal, and that is load-bearing** — the same
// reason checkImports.test.js gives. `scripts/checkImports.js` scans this
// directory too, so an ordinary quoted string holding a relative require would
// make this file fail that check. Templates are blanked by the stripper.

const test = require('node:test')
const assert = require('node:assert')
const fs = require('node:fs')
const os = require('node:os')
const path = require('node:path')

const {
  reachable,
  resolveFile,
  checkDeclaration,
  checkBundle,
  declaredServerPaths,
  runtimeDependencies,
} = require('../scripts/checkBundle')

/**
 * Write a throwaway module tree: `files` under server/, `bundle` as its
 * ci/bundle.json, `pkg` as its server/package.json. Returns the module root.
 */
function fixture(files, bundle = { server: ['index.js'] }, pkg = null) {
  const root = fs.mkdtempSync(path.join(os.tmpdir(), 'module-rust-bundle-'))
  for (const [name, source] of Object.entries(files)) {
    const file = path.join(root, 'server', name)
    fs.mkdirSync(path.dirname(file), { recursive: true })
    fs.writeFileSync(file, source)
  }
  fs.mkdirSync(path.join(root, 'ci'), { recursive: true })
  fs.writeFileSync(path.join(root, 'ci', 'bundle.json'), JSON.stringify(bundle))
  if (pkg) {
    fs.mkdirSync(path.join(root, 'server'), { recursive: true })
    fs.writeFileSync(path.join(root, 'server', 'package.json'), JSON.stringify(pkg))
  }
  return root
}

const cleanup = (root) => fs.rmSync(root, { recursive: true, force: true })

// ── The regression this script was written for ─────────────────────────────

test('--check catches a directory the include list has stopped covering', () => {
  const root = fixture(
    {
      'index.js': `const r = require('./router/public/rust.router')`,
      'router/public/rust.router.js': `module.exports = {}`,
    },
    { server: ['index.js'] }, // `router` missing — exactly Module-uo's v1.0.0
  )
  try {
    const { uncovered } = checkDeclaration(root)
    assert.strictEqual(uncovered.size, 1)
    assert.ok(uncovered.has('server/router'))
  } finally {
    cleanup(root)
  }
})

test('--bundle catches the file missing from an assembled tarball', () => {
  const root = fixture({ 'index.js': `require('./router/public/rust.router')` })
  try {
    const { missing } = checkBundle(root)
    assert.strictEqual(missing.length, 1)
    assert.strictEqual(missing[0].specifier, './router/public/rust.router')
  } finally {
    cleanup(root)
  }
})

// ── This module's own version of that failure ──────────────────────────────
//
// The release packs no node_modules because the shipped half declares no
// dependencies (org lead, phase 2). The value of that decision is entirely in
// the day it stops being true being a LOUD day, so both modes ask.

test('--check reports a runtime dependency the release would not pack', () => {
  const root = fixture({ 'index.js': `module.exports = 1` }, { server: ['index.js'] }, {
    name: 'x',
    dependencies: { ws: '^8.21.0' },
  })
  try {
    assert.deepStrictEqual(checkDeclaration(root).dependencies, ['ws'])
  } finally {
    cleanup(root)
  }
})

test('--bundle reports a dependency the assembled bundle declares and does not carry', () => {
  const root = fixture({ 'index.js': `module.exports = 1` }, { server: ['index.js'] }, {
    name: 'x',
    dependencies: { ws: '^8.21.0' },
  })
  try {
    assert.deepStrictEqual(checkBundle(root).dependencies, ['ws'])
  } finally {
    cleanup(root)
  }
})

test('devDependencies are not runtime dependencies', () => {
  // express, express-validator and swagger-autogen are all here and none of them
  // ships: the shipped half is handed express on `ctx` (§2.3). A check that
  // confused the two would fail on a correct repo, which is the one way to make
  // everyone stop reading it.
  const root = fixture({ 'index.js': `module.exports = 1` }, { server: ['index.js'] }, {
    name: 'x',
    devDependencies: { express: '^4.19.2' },
  })
  try {
    assert.deepStrictEqual(runtimeDependencies(root), [])
  } finally {
    cleanup(root)
  }
})

// ── It has to reach requires that are not at the top level ─────────────────

test('follows requires written inside a function', () => {
  // index.js requires inside `register()` because require order is load-bearing:
  // `core.init(ctx)` has to run before anything under router/ is required. A
  // check that only saw file-scope requires would miss every router this module
  // has.
  const root = fixture(
    {
      'index.js': `module.exports = function register(ctx) { const r = require('./router/a') }`,
      'router/a.js': `module.exports = {}`,
    },
    { server: ['index.js', 'router'] },
  )
  try {
    assert.strictEqual(checkDeclaration(root).uncovered.size, 0)
    assert.strictEqual(checkBundle(root).missing.length, 0)
  } finally {
    cleanup(root)
  }
})

test('follows requires transitively, not just one hop', () => {
  const root = fixture(
    {
      'index.js': `require('./a')`,
      'a.js': `require('./b')`,
      'b.js': `require('./deep/c')`,
      'deep/c.js': `module.exports = {}`,
    },
    { server: ['index.js', 'a.js', 'b.js'] }, // `deep` missing
  )
  try {
    assert.ok(checkDeclaration(root).uncovered.has('server/deep'))
  } finally {
    cleanup(root)
  }
})

// ── Resolution has to match Node's, or it invents failures ─────────────────

test('resolves a directory to its index.js', () => {
  const root = fixture(
    { 'index.js': `require('./boot')`, 'boot/index.js': `module.exports = {}` },
    { server: ['index.js', 'boot'] },
  )
  try {
    assert.strictEqual(checkDeclaration(root).uncovered.size, 0)
  } finally {
    cleanup(root)
  }
})

test('resolves a .json dependency, and does not try to parse it for requires', () => {
  // server/index.js's last line requires ../module.json, which is why this case
  // is not hypothetical and why `generated` is in the declared list at all.
  const root = fixture(
    { 'index.js': `require('./data/atlas.json')`, 'data/atlas.json': `{"a":1}` },
    { server: ['index.js', 'data'] },
  )
  try {
    const { uncovered, missing } = checkDeclaration(root)
    assert.strictEqual(missing.length, 0)
    assert.strictEqual(uncovered.size, 0)
  } finally {
    cleanup(root)
  }
})

test('survives a require cycle', () => {
  const root = fixture(
    { 'index.js': `require('./a')`, 'a.js': `require('./index')` },
    { server: ['index.js', 'a.js'] },
  )
  try {
    assert.strictEqual(checkDeclaration(root).uncovered.size, 0)
  } finally {
    cleanup(root)
  }
})

test('a specifier that resolves to nothing is reported, not thrown', () => {
  const root = fixture({ 'index.js': `require('./gone')` })
  try {
    const { missing } = checkDeclaration(root)
    assert.strictEqual(missing.length, 1)
    assert.strictEqual(missing[0].specifier, './gone')
  } finally {
    cleanup(root)
  }
})

test('prose describing a require is not a require', () => {
  // The failure mode checkImports.js hit the first time it ran: index.js's own
  // header explains why it must never require express, and comments in this repo
  // name module paths constantly.
  const root = fixture(
    { 'index.js': `// this file used to require('./router/gone')\nmodule.exports = 1` },
    { server: ['index.js'] },
  )
  try {
    assert.strictEqual(checkDeclaration(root).missing.length, 0)
  } finally {
    cleanup(root)
  }
})

test("node_modules inside a bundle is npm's business, not this check's", () => {
  // Nothing ships one today. The skip stays so that the day a dependency does
  // arrive, this is not also the thing that breaks.
  const root = fixture({
    'index.js': `module.exports = 1`,
    'node_modules/ws/index.js': `require('./lib/that-npm-owns')`,
  })
  try {
    assert.strictEqual(checkBundle(root).missing.length, 0)
  } finally {
    cleanup(root)
  }
})

// ── And the real repo, which is the check that actually gates a release ────

test('the real ci/bundle.json covers everything the real entry point reaches', () => {
  const { uncovered, missing, reached, dependencies } = checkDeclaration()
  assert.deepStrictEqual([...uncovered.keys()], [])
  assert.deepStrictEqual(missing, [])
  assert.deepStrictEqual(dependencies, [])
  assert.ok(reached > 1, 'the walk should reach more than the entry point itself')
})

test('every path ci/bundle.json declares exists', () => {
  // A list naming a path that has moved packs nothing and says nothing — `cp` in
  // the release would fail, but only after the tag had been pushed.
  for (const p of declaredServerPaths()) {
    assert.ok(fs.existsSync(p), `ci/bundle.json names ${p}, which does not exist`)
  }
})

test('the entry point is reachable from the declared list', () => {
  const entry = path.resolve(__dirname, '..', 'index.js')
  assert.ok(reachable(entry).files.includes(entry))
  assert.ok(resolveFile(path.dirname(entry), './core'))
})