feat(puppeteer): impl DOMWorld.$ for xpath: selector

[mokeyish]

#5746

explicit locator strategy

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[mokeyish]

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[mathiasbynens]

This would need documentation as well.

Either way, we're currently investigating adding this functionality more generically, so that folks can register custom query handlers and then opt-in to them for any part of the API that accepts a selector. It seems like opting in to XPath (as opposed to using page.$x) would be a good fit.

[mathiasbynens]

cc @paullewis

[mathiasbynens]

We decided to go with custom query handlers instead. The implementation is currently experimental, and you can read about it here: https://github.com/puppeteer/puppeteer/releases/tag/v3.0.3 It should enable you to build what you had in mind! Please give it a try and let us know if you run into any issues.