Multiple spaces in thread subject fails 'url' validation

[devcircus]

After noticing #318, I started looking closer and this is what I found.

Issue

If, in your 'subject', you include multiple spaces between words, the 'DoesNotContainUrl' validation error will be triggered. This is because the following code successfully passes validation:

// from line 24 in DoesNotContainUrlRule.php

$validator->make(['word' => ''], ['word' => 'url'])->passes();

// returns true (which, in turn, causes false to be returned from the rule)

When we explode the subject and pass each element to the above validator, any elements that are an empty string will allow the validation to pass. Therefore the custom rule will fail.

Possible solutions

EDITED

1. Add 'required' to the inner loop that validates each part of the string as a url. This way, if an empty string is checked, it will pass; allowing the custom rule to fail.
2. Remove the extra spaces prior to the inner validation loop.
3. Add sanitization to inputs, either at the middleware or form-request level.

[devcircus]

I've submitted #322 that takes the approach of the first solution listed above. I do think input sanitization would be a better long-term solution.
With sanitization, we could keep subjects like the following, out of the database:

This        is   my       subject with a           lot of        spaces.