add email validate

[Paarmita]

Make sure these boxes are checked before your pull request is ready to be reviewed and merged. Thanks!

Solves #1996

• all tests pass -- rake test:all
• code is in uniquely-named feature branch, and has been rebased on top of latest master (especially if you've been asked to make additional changes)
• pull request is descriptively named with #number reference back to original issue

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We have a loose schedule of reviewing and pulling in changes every Tuesday and Friday, and publishing changes on Fridays. Please alert developers on plots-dev@googlegroups.com when your request is ready or if you need assistance.

Thanks!

[SidharthBansal]

You need to use the regex in the line mentioned.
You don't need to write it separately

[SidharthBansal]

We are glad to see your Pull request.
Thanks for the PR. I have mentioned some changes go for it.
Also, write a test to demonstrate that pratima@gmail will not lead to signup in the plots2/test/unit/user_test.rb. Make sure that all the tests pass.

[jywarren]

Hi! Looks like you're having some issues -- maybe @publiclab/reviewers can help out. You can always look through the output of the tests to see what the errors are, by clicking on the little red X next to your last commit:

https://travis-ci.org/publiclab/plots2/builds/328785772

Thanks for your contribution!! I'm sure we'll figure it out.

[ryzokuken]

Hi, @Paarmita! Thanks for being so patient and kudos for taking this step to improve publiclab. It really means a lot to all of us.

I see your pull request is getting an error, specifically: SyntaxError: /app/app/models/user.rb:38: empty range in char class: /\A[\w+-.]+@[a-z\d-.]+.[a-z]+\z/i

This most probably means that there's something wrong with the Regex, so I'd advise you to kindly take a look at it again.

[ryzokuken]

Spoiler alert: \A[-\w+.]+@[\da-z-.]+.[a-z]+\z seemed to work.

[jywarren]

http://rubular.com/ could be helpful to test out regex!! Thanks!

…

On Tue, Jan 16, 2018 at 2:35 PM, Ujjwal Sharma ***@***.***> wrote: Spoiler alert: \A[-\w+.]+@[\da-z-.]+.[a-z]+\z seemed to work. — You are receiving this because you are on a team that was mentioned. Reply to this email directly, view it on GitHub <#1999 (comment)>, or mute the thread <https://github.com/notifications/unsubscribe-auth/AABfJwtFYuJVEftvqN9k2iCSYcmA4R8bks5tLPoGgaJpZM4RdVSY> .

[namangupta01]

@Paarmita Do you need any help with this? Please, let us know! We are happy to help.

[Ankit-Singla]

@ryzokuken \A[-\w+.]+@[\da-z-.]+.[a-z]+\z doesn't work, because of the . that matches any character except for the newline character. It should be replaced by [.] for it to actually match the . character.

[ryzokuken]

@Ankit-Singla idk, you should use whatever works in the tests, I tried that Regex on rubular and it seemed to work.

[jywarren]

@Paarmita @Ankit-Singla @ryzokuken how's this coming along? Sorry this is a little more complex -- just a suggestion -- you can take a test string and input it in http://rubular.com with the regex you're using, like this:

http://rubular.com/r/vKHN1A7H4k

@Ankit-Singla can you offer an example of why the above regex would fail, and how your proposed improvement would be better? Thank you!

[Ankit-Singla]

@jywarren The regex suggested by @ryzokuken ( \A[-\w+.]+@[\da-z-.]+.[a-z]+\z ) doesn't work because it doesn't match the . in the email address correctly.
http://rubular.com/r/YMcSHIJzAT
You can see here that it gives a match when the user email is "jeff@publiclab", while ideally it shouldn't match. Thus, it doesn't enforce the presence of . in the email address.
I suggested ( \A[-\w+.]+@[\da-z-.]+.[a-z]+\z ), replacing the . by \. or [.], which matches the . literally, and not the characters represented by ..

[ryzokuken]

@SidharthBansal was this already fixed in a PR?

[SidharthBansal]

Parmita left and ankit was doing this. So I closed this pr