fix(deploy-suite): extract CJS->ESM converter to standalone script

[james-elicx]

Summary

• Move the next.config.{js,ts} CJS→ESM converter out of an inlined node -e '…' blob in scripts/e2e-deploy.sh and into a standalone scripts/cjs-to-esm-config.mjs. Same regex pipeline, no behavioural change.
• Add a bash -n scripts/*.sh gate to the Check job so this class of regression can't ship green.

Why

The deploy-suite run 25869359604 reported 329 passed, 2480 failed, 653 skipped — a 9.5% pass rate. Investigating, every single failure was byte-identical:

Error: Custom deploy script failed:  undefined (2)
  at NextDeployInstance.deployUsingCustomScript (next.js/test/lib/next-modes/next-deploy.ts:70:13)

…and the runner logs showed the real cause:

scripts/e2e-deploy.sh: line 490: syntax error near unexpected token `('
scripts/e2e-deploy.sh: line 490: `      // TODO: This doesn't perfectly handle all CJS patterns (e.g. dynamic'

bash -n scripts/e2e-deploy.sh reproduces the error locally on 843df83.

Root cause

The CJS→ESM converter (added in #1189) was passed to node -e as a single-quoted bash argument. The JS body used the '\"'\"' quote-escape trick repeatedly inside regex literals. The net effect rebalanced quoting such that some later lines — notably the comment // TODO: … (e.g. dynamic … on line 490 — sat outside a single-quoted bash region. Bash then saw (e.g. dynamic …) as shell syntax and refused to parse the whole script.

The deploy step exited with status 2 before doing any work, so every deploy-suite test failed at createNext() setup before any vinext code was exercised. The 329 "passes" were almost entirely should skip next deploy placeholders, not real assertions — effective real-test pass rate this run was 0%.

What the fix does

• scripts/cjs-to-esm-config.mjs: new standalone Node script with the identical regex pipeline (handles module.exports = X, const X = require('mod'), const X = require('mod')(args), const { a, b } = require('mod'), and bare require('mod') in expressions). Lives in a .mjs file so its source is never re-parsed by bash.
• scripts/e2e-deploy.sh: the old 60-line node -e '…' blob is replaced by node "${VINEXT_DIR}/scripts/cjs-to-esm-config.mjs" "${config_file}". Net -65 / +13 lines in the bash script.
• .github/workflows/ci.yml: new step in the Check job runs bash -n on every scripts/*.sh. If anyone reintroduces a syntax error in a deploy-critical shell script, the Check gate fails on the PR.

Verification

Locally:

$ bash -n scripts/e2e-deploy.sh && echo OK
OK
$ for f in scripts/*.sh; do bash -n "$f" || echo FAIL $f; done
(all clean)

Smoke-tested the converter against a representative next.config.js:

// input
const path = require('path')
const withPWA = require('next-pwa')({ dest: 'public' })
const { withSentryConfig } = require('@sentry/nextjs')

module.exports = withPWA({
  reactStrictMode: true,
  basePath: '/myapp',
})

// output (validated with `node --check --input-type=module`)
import _cjsImport0 from 'next-pwa';
import path from 'path';
import { withSentryConfig } from '@sentry/nextjs';

const withPWA = _cjsImport0({ dest: 'public' })

export default withPWA({
  reactStrictMode: true,
  basePath: '/myapp',
})

The regex pipeline is byte-for-byte the one that was inlined; only the wrapping changed.

Follow-up (not in this PR)

The harness reported undefined for stderr in every failure (Custom deploy script failed: undefined (2)), which made the root cause invisible in the test report — you have to dig into raw runner logs to find the bash syntax error. The deploy-debug-N artifacts also only contain context.txt and package.json, no stdout/stderr capture from the deploy script itself. Worth a separate PR to fix the harness so future failures of this class are visible in the test report.

After this lands, re-run the deploy suite to get the first real parity signal. With the harness fixed, the run will surface actual vinext bugs and parity gaps instead of one repeated harness error.

[pkg-pr-new]

Open in StackBlitz

npm i https://pkg.pr.new/vinext@1209

commit: 4fc21a8

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