TE-15304: re-roll dom-serializer bundle (fix page.evaluate "Unexpected token 'function'" regression)

[shrinishLT]

TL;DR

PR #522 shipped a dom-serializer bundle that breaks every SDK injecting via page.evaluate(bundle) (playwright, puppeteer, webdriverio) with:

SyntaxError: Unexpected token 'function'

This follow-up replaces the broken bundle with a re-rolled one that starts with (function(...) — a valid expression-context IIFE that all SDK injection patterns accept.

JIRA: TE-15304

Cause

The bundle at src/dom/dom-serializer.js is a pre-built artifact generated by webpack + webpack-obfuscator in smartui-cli-dom-serializer, then committed verbatim here. webpack-obfuscator's output is non-deterministic — for the same source, builds randomly produce one of:

Form	Looks like	% of builds
A. IIFE-wrapped	(function(_0x...){...})()	~20%
B. Hoisted helper first	function a0_0xNNNN(...){...} ...	~80%

The stringArray: true and selfDefending: true features in the obfuscator config cause helper function declarations to be hoisted to top level. Their hoisting is randomized between runs.

PR #522's bundle was form B — a hoisted helper at the top. Empirically verified with a 10-run experiment (5 baseline + 5 with TE-15304); both setups produced 60–80% bad rolls.

Why it's an SDK-side bug only some of them hit

page.evaluate(str) evaluates str as a JavaScript expression. A leading function declaration (form B) is a statement and throws SyntaxError. Other injection patterns are unaffected:

SDK	Injection	Form B bundle
@lambdatest/cypress-driver	eval(bundle) (evaluates as program)	✓ works
@lambdatest/selenium-driver	executeScript(bundle) (script-tag-style)	✓ works
@lambdatest/playwright-driver	page.evaluate(bundle)	✗ throws SyntaxError
@lambdatest/puppeteer-driver	page.evaluate(bundle)	✗ throws SyntaxError
@lambdatest/webdriverio-driver	browser.execute(bundle)	✗ throws SyntaxError

This is why the regression slipped past review — most internal flows use selenium/cypress, where the broken bundle still worked.

Fix in this PR

Single file changed: src/dom/dom-serializer.js. No source code or build pipeline changes here.

Re-ran npm run build:prod in the serializer repo until the obfuscator landed a form-A roll, then committed that artifact. Verified locally:

• Bundle now starts with (function(_0x40c4a2,_0x2284c6){... ✓
• make use-cli-branch BRANCH=TE-15304 followed by make upd-cli TEST=test-playwright.js runs the playwright SDK end-to-end without Unexpected token errors ✓
• Snapshot processed successfully on the cloud ✓

Follow-up (separate PR, NOT in this one)

The underlying obfuscator non-determinism remains — the next maintainer who rebuilds and commits a new bundle has the same 80% chance of regressing this. A proper fix is to disable stringArray, selfDefending, and splitStrings in the obfuscator config so output is always IIFE-wrapped (and ~27% smaller). That change reduces obfuscation strength slightly and warrants a separate discussion + PR against smartui-cli-dom-serializer. Until then, anyone rebuilding the bundle should:

# verifies bundle starts with `(`
head -c 40 src/dom/dom-serializer.js

Test plan

• Local end-to-end: playwright SDK injects, snapshot captured, no error
• Selenium SDK still works (unchanged bundle injection path)
• Reviewer runs the same playwright-driver test against a stage deploy carrying this commit
• Confirm make use-cli-branch BRANCH=stage (after merge) shows ✓ GOOD ROLL — IIFE-wrapped

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