Benchmark: undefined vs typeof vs in vs hasOwnProperty / ver. 2

Script Preparation code:

var obj = { a: 1, b: 2, c: 3, d: 4, e: 5 };
var keys = new Array(4096 * 5);
for (let i = 0; i < keys.length; i += 1)
  keys[i] = Math.random().toString();
for (let i = 0; i < keys.length; i += 2)
  obj[keys[i]] = i;

Tests:

undefined
for (let i = 0; i < 4096; i += 1) obj[keys[4096 * 0 + i]] === undefined;
typeof
for (let i = 0; i < 4096; i += 1) typeof obj[keys[4096 * 1 + i]] === "undefined";
in
for (let i = 0; i < 4096; i += 1) keys[4096 * 2 + i] in obj;
hasOwnProperty
for (let i = 0; i < 4096; i += 1) obj.hasOwnProperty(keys[4096 * 3 + i]);
bool
for (let i = 0; i < 4096; i += 1) !obj[keys[4096 * 4 + i]];

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
undefined
typeof
in
hasOwnProperty
bool

Fastest: N/A

Slowest: N/A

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Latest run results:

Run details: (Test run date: 2 years ago)

User agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_7) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/99.0.4844.74 Safari/537.36

Browser/OS: Chrome 99 on Mac OS X 10.15.7

View result in a separate tab

Test name	Executions per second
undefined	1137.2 Ops/sec
typeof	1876.4 Ops/sec
in	1853.8 Ops/sec
hasOwnProperty	1424.0 Ops/sec
bool	1840.1 Ops/sec

undefined vs typeof vs in vs hasOwnProperty / ver. 2 (version: 0)

Object lookup performance

Comparing performance of: undefined vs typeof vs in vs hasOwnProperty vs bool

Created: 2 years ago by: Guest

Jump to the latest result

undefined

typeof

in

hasOwnProperty

bool

Suite status: <idle, ready to run>

Experimental features:

Fastest: N/A

Slowest: N/A