Rails regex won't work, but Javascript regex does

Question

I've read this question and changed my rails model code accordingly: Regular expressions with validations in RoR 4

Here's my regex for my datetime in rails:

/\A((19[7-9][0-9])|(2[0-9][0-9][0-9]))\/((0[1-9])|(1[0-2]))\/(([0-2][0-9])|(3[0-1]))\s(([0-1][0-9])|(2[0-4]))\:([0-5][0-9])\z/

This regex below works in javascript, though:

/^((19[7-9][0-9])|(2[0-9][0-9][0-9]))\/((0[1-9])|(1[0-2]))\/(([0-2][0-9])|(3[0-1]))\s(([0-1][0-9])|(2[0-4]))\:([0-5][0-9])$/

I'm trying to pass a datetime string to them both, but I can't understand why it keeps failing. Here's the string:

2014/12/02 11:06

I thought my model code might be helpful:

validates :start, presence: true, format: { :with => /\A((19[7-9][0-9])|(2[0-9][0-9][0-9]))\/((0[1-9])|(1[0-2]))\/(([0-2][0-9])|(3[0-1]))\s(([0-1][0-9])|(2[0-4]))\:([0-5][0-9])\Z/, :message => "must be in this format: YYYY/MM/DD HH:MM" }
validates :finish, presence: true, format: { :with => /\A((19[7-9][0-9])|(2[0-9][0-9][0-9]))\/((0[1-9])|(1[0-2]))\/(([0-2][0-9])|(3[0-1]))\s(([0-1][0-9])|(2[0-4]))\:([0-5][0-9])\Z/, :message => "must be in this format: YYYY/MM/DD HH:MM" }

Edit: I figured out what the issue is, but I still don't know how to fix it...

For some reason when I submit my form the date 2014/12/24 16:19 is being cut down to just 2014. This then fails validation and throws the error.

Can anyone help me figure this out?

your regexp for ruby is correct, and it matches the provided string — Малъ Скрылевъ, Dec 24 '14 at 17:58
@August I think my text_fields might be adding a new line to the end of the string. I tried adding a newline to the code you provided and it failed. Is there a way I can strip the newlines before submitting? — daraul, Dec 24 '14 at 18:11
I think rails is cutting my input down to just the year for some reason. I don't know why, though — daraul, Dec 24 '14 at 20:09
I figured out the problem: my datetime is being cut down to just the year (or anything before the first "/" I assumed) before being validated. Can anyone tell me why this is happening and how to get around it? — daraul, Dec 24 '14 at 20:37

score 1 · Accepted Answer · edited May 23 '17 at 11:59

Your regexp for ruby part is correct, and it matches the provided string:

re = /\A((19[7-9][0-9])|(2[0-9][0-9][0-9]))\/((0[1-9])|(1[0-2]))\/(([0-2][0-9])|(3[0-1]))\s(([0-1][0-9])|(2[0-4]))\:([0-5][0-9])\z/
'2014/12/02 11:06' =~ re # => 0

Some notes:

See the SO topics 1, 2, and 3 with explanation on how to match date in ruby.
Use regexp online services rubular.com, or rubyxp.com to validate regexp match for ruby language, embedded irb app, or debug pry gem.

Rails regex won't work, but Javascript regex does

1 Answers1