Benchmark: key exists: key in object vs !!object[key]

Script Preparation code:

testObject = {'asdf': 'apple', 'afwefg': 'pear', 'hohoo': 'santa', 'country': 'usa', 'bottle': 'gin'};

Tests:

Rendered benchmark preparation results:

Previous results

Test case name	Result
key in object
!!object[key]

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Latest run results:

Run details: (Test run date: 5 years ago)

User agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10_14_0) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/70.0.3538.77 Safari/537.36

Browser/OS: Chrome 70 on Mac OS X 10.14.0

Test name	Executions per second
key in object	6845599.0 Ops/sec
!!object[key]	7531414.0 Ops/sec

key exists: key in object vs !!object[key] (version: 0)