bug: --shuffle flag silently ignored after #5438 (sort() in run() overwrites shuffle from loadTests()) #5605

Bug Report

Introduced in: commit 4f1eb3f (PR #5438) — fix: run-workers --by suite parallelization broken by test file sorting

What was fixed in #5438

testFiles.sort() was moved from loadTests() to run() to fix worker suite distribution. Good fix — but it introduced a regression for --shuffle users.

The regression

In lib/codecept.js, the execution order is now:

// loadTests() — line ~217
if (this.opts.shuffle) {
  this.testFiles = shuffle(this.testFiles)  // ✅ shuffled here
}

// run() — line 293 (added by #5438)
this.testFiles.sort()  // ❌ always sorts — overwrites the shuffle!

// then:
mocha.files = this.testFiles  // receives sorted, not shuffled, files

sort() in run() is unconditional — it runs regardless of whether --shuffle was specified. This means --shuffle is silently ignored on every run after this commit.

Steps to reproduce

# Run twice with --shuffle — expect different order each time
npx codeceptjs run --shuffle
npx codeceptjs run --shuffle

# Both runs will produce identical alphabetical order — shuffle has no effect

Expected behavior

--shuffle randomizes test execution order. Each run should produce a different sequence.

Actual behavior

Both runs produce identical alphabetical order. The shuffle applied in loadTests() is overwritten by sort() in run().

Suggested fix

Guard the sort with a shuffle check:

// run() — only sort if shuffle is not active
if (!this.opts.shuffle) {
  this.testFiles.sort()
}

This preserves alphabetical order for normal runs while respecting shuffle when requested.

Happy to submit a PR if the fix looks right to maintainers.