modifyObstructiveCode incorrectly matches the word 'stop'

[mikey0000]

Current behavior:

During test run, code fails with sself not defined.

Desired behavior:

functionality of code should not be replaced
isChildTrainPlatform = stop => stop.route_type === STOP_TYPE.TRAINSTOP && stop.location_type === 0;
should not turn into
isChildTrainPlatform = stop => stop.route_type === STOP_TYPE.TRAINSTOP && sself.location_type === 0;

Steps to reproduce: (app code and test code)

code specifically with this line

return stop.route_type===WEBPACK_IMPORTED_MODULE_10__types_stop_types["a" /* default */].TRAINSTOP&&stop.location_type===0;

Versions

Cypress 3.4.1, Chrome 77

[kuceb]

paging @flotwig, he's working with our app isolation logic

[flotwig]

Your code is getting mangled by these regexes in the proxy which blindly replace top with self:

cypress/packages/server/lib/util/security.js

Lines 7 to 10 in 5654680

	const topOrParentEqualityBeforeRe = /((?:window|self)(?:\.|\[['"](?:top|self)['"]\])?\s*[!=]==?\s*(?:(?:window|self)(?:\.|\[['"]))?)(top|parent)(?![\w])/g
	const topOrParentEqualityAfterRe = /(top|parent)((?:["']\])?\s*[!=]==?\s*(?:window|self))/g
	const topOrParentLocationOrFramesRe = /([^\da-zA-Z\(\)])?(top|parent)([.])(location|frames)/g
	const jiraTopWindowGetterRe = /(!function\s*\((\w{1})\)\s*{\s*return\s*\w{1}\s*(?:={2,})\s*\w{1}\.parent)(\s*}\(\w{1}\))/g

I am working on a PR that parses and rewrites the Javascript instead of using regexes, which I'll make sure fixes this problem: #5273

[mikey0000]

Yeah, I managed to work that out, awesome! Look forward to the fix!

[brian-mann]

s + top === stop ;-P

[kjellski]

This is exactly what happened to us as well and we would have reported another bug here as well. We were just accessing a variable like this:

... purchasedStop.location ... which ended up breaking our application code like this: ... purchasedSself.location .... Isn't thisa bug and unintended behaviour?
I think it would be a good first step to make sure that the string is not part of other symbols, like checking that it only occures without valid characters before or after that :)

[jennifer-shehane]

Closing as resolved.

If you're experiencing a bug similar to this in Cypress, please open a new issue with a fully reproducible example that we can run. There may be a specific edge case with the issue that we need more detail to fix.