1858595 - Date.parse parses the time "01::01" as 01:01:00

Status: NEW

(Core :: JavaScript: Standard Library, defect, P3)

Description

[Vinny Diehl]

Discovered this parity bug while working on bug 1557650. V8 parses this oddball time format as 01:00:01, while SpiderMonkey parses it as 01:01:00.

> eshost -te 'new Date("Mar 01 1991 01::01").toString()'

Engine	Result
JavaScriptCore	Invalid Date
SpiderMonkey	Fri Mar 01 1991 01:01:00 GMT-0700 (Mountain Standard Time)
V8	Fri Mar 01 1991 01:00:01 GMT-0700 (Mountain Standard Time)

Comment 1

[Will Medina [:willyelm]]

We'll set a priority of P3 based on the parent issue 1557650

Comment 2

[Vinny Diehl]

Looking into this deeper has revealed more quirks about how Chrome handles colons:

Input	JavaScriptCore	SpiderMonkey	V8
"05:Mar:2015"	Invalid Date	Invalid Date	Sun Mar 01 2015 05:00:00 GMT-0700 (Mountain Standard Time)
"05:02:03:Mar:2015"	Invalid Date	Invalid Date	Sun Mar 01 2015 05:02:03 GMT-0700 (Mountain Standard Time)
"05:02:03:04:Mar:2015"	Invalid Date	Invalid Date	Sun Mar 01 2015 05:02:03 GMT-0700 (Mountain Standard Time)
"Mar:05:02:03:04:2015"	Invalid Date	Invalid Date	Sun Mar 01 2015 05:02:03 GMT-0700 (Mountain Standard Time)
"05:02:03:Mar:06:2015"	Invalid Date	Invalid Date	Sun Mar 01 2015 05:02:03 GMT-0700 (Mountain Standard Time)
"Mar:05:02:03:04:06 2015"	Invalid Date	Invalid Date	Fri Mar 06 2015 05:02:03 GMT-0700 (Mountain Standard Time)
"Mar:05:02:03:04: 06:2015"	Invalid Date	Invalid Date	Invalid Date

What I make of this:

• Colons are legal anywhere in the date, but cannot be between the mday and year or mday will not be parsed
• The time can be anywhere in the date string
• A colon after a number will initiate the parsing of a time, until a non-number is reached
• Numbers after the seconds have been parsed are ignored

Not all of this behavior will necessarily be copied in this bug, but as the colon parsing will need to be reworked here, this is worth noting.