Run results for: "delete" vs "spread syntax" vs "set to undefined"

Run details:

User agent: Mozilla/5.0 (X11; Ubuntu; Linux x86_64; rv:109.0) Gecko/20100101 Firefox/112.0

Browser: Firefox 112

Operating system: Ubuntu

Device Platform: Desktop

Date tested: one year ago

Test name	Executions per second
delete	1542193.0 Ops/sec
set to undefined	43252960.0 Ops/sec
spread syntax	62547.2 Ops/sec

Script Preparation code:

var obj = {
  a: 1,
  b: 2,
  c: 3,
  d: 4,
  e: 5,
  f: 6,
  g: 7,
  h: 8,
  i: 9,
  j: 10,
  k: 11,
  l: 12,
  m: 13,
  n: 14,
  o: 15,
  p: 16,
  q: 17,
  r: 18,
  s: 19,
  t: 20,
  u: 21,
  v: 22,
  w: 23,
  x: 24,
  y: 25,
  z: 26
};

Tests:

delete
delete obj['c'] delete obj['f'] delete obj['i'] delete obj['l'] delete obj['o'] delete obj['r'] delete obj['u'] delete obj['x']
set to undefined
obj['c'] = undefined obj['f'] = undefined obj['i'] = undefined obj['l'] = undefined obj['o'] = undefined obj['r'] = undefined obj['u'] = undefined obj['x'] = undefined
spread syntax
const {c, ...restC} = obj const {f, ...restF} = obj const {i, ...restI} = obj const {l, ...restL} = obj const {o, ...restO} = obj const {r, ...restR} = obj const {u, ...restU} = obj const {x, ...restX} = obj