Unexpected behaviour when logging out 'undefined'

[Matt Grande]

Steps to reproduce

1. Go the the repl
2. Enter this: const z = [null, undefined]
3. console.log(z)

Expected result

You should see [null, undefined] in the right-hand side

Actual result

You see [null, null]

Browser: Chrome 59.0.3071.115
OS: OSX 10.12.5 (Sierra)

Kinda strange; I'm mostly just curious if others have seen this issue.

[buzzdecafe]

yeah that is strange. It appears to be just in the way console.log works. If you just do:

const z = [null, undefined]
z;

the right side of the repl responds with [null, undefined]. Since it evaluates correctly, this doesn't strike me as a crisis, just another hairy js edge.