Support Gem::Version properly

[knewter]

I haven't tested this with rails < 4-master, but this fixes breakage where Rails.version now returns a Gem::Version and these comparisons fail there. This is the offending commit afaict: rails/rails@c07e151

[jnicklas]

That seems weird. Comparing string sizes like this seems incorrect to me. For example:

>> "3.1.2.beta1" > "3.1.2"
=> true

[knewter]

That's an excellent point, though I have no idea what to_f did with that. I didn't even consider that case, though it's obvious now. How is Gem::Version intended to be compared?

[abotalov]

Here's even more weird example:

'3.1.2' > '3.1.10' # => true 

What about <=>:
Rails.version >= Gem::Version(3.0)

[jnicklas]

@abotalov if Rails previously returned something other than a Gem::Version that might break on older versions.

[abotalov]

@jnicklas What about:

if Rails.version.is_a?(String)
  Gem::Version.new(Rails.version) >= Gem::Version.new(3.0)
else
 Rails.version >= Gem::Version.new(3.0)
end

[jnicklas]

I'm not even sure what it was before, was it really a string?

[abotalov]

@jnicklas

1.9.3p286 :015 > Rails.version
 => "3.2.11" 

[eval]

How about:

Gem::Version.new(Rails.version) >= Gem::Version.new(3)

This is compatible with Rails.version being a string or Gem::Version

[jnicklas]

I cherry picked this onto 2.0_stable and released it as 2.0.3 together with another tweak. A simple bundle update capybara should now fix this issue.