An edge case is not covered in minification-estimator.js

[avinash-sd]

FAQ

• Yes, my issue is not about variability or throttling.
• Yes, my issue is not about a specific accessibility audit (file with axe-core instead).

URL

https://example.com

What happened?

While checking lighthouse reports, I noticed abnormally large Potential Savings size in minify JS opportunity for a javascript file that is minified already.

What did you expect?

I expected the lighthouse report to not list minified JS files in this minify JS opportunity.

What have you tried?

I inspected the code of minification-estimator.js with that JS file I have encountered with this problem. Turns out that the file contained this patch of code in middle of the file:
else/VALID_REGEX_PATTERN/.test(n)?(d=(new DOMParser).parseFromString("...
When the loop hit the /VALID_REGEX_PATTERN/, it doesn't consider it as a regex and the subsequent totalTokenLength calculation is messed up.

I added else in PUNCTUATOR_REGEX variable in minification-estimator.js, then it worked fine.

How were you running Lighthouse?

node

Lighthouse Version

11.1.0

Chrome Version

No response

Node Version

No response

OS

No response

Relevant log output

No response

[connorjclark]

Wow, very impressive code sleuthing! Thanks for sharing your fix. Happy to commit it myself, but would you like to do the honors? No worries if not.

[avinash-sd]

Yeah sure! I like to do it myself 😇

[avinash-sd]

Issue resolved! #15624