Adding RouteParser::getBasePath method

[piotr-cz]

See #2837

At this moment it's not trivial to retrieve basePath from code that doesn't have access to App or RouteCollector instances (and in my opinion code responsible for rendering responses shouldn't have).

RouteParser class seems like good place for it as

• it contains other related methods (relativeUrlFor, urlFor, fullUrlFor)
• it can be available as a route attribute (and indirectly in middleware) when using App::addRoutingMiddleware

I haven't implemented in this PR other methods that could be helpful like baseUrl by purpose as I'm not sure if it should be implemented in Slim or view classes.

[coveralls]

Coverage remained the same at 100.0% when pulling fd3449f on piotr-cz:feature/routeparser-basepath into a24fac2 on slimphp:4.x.

[odan]

IMHO: For the sake of "symmetry", the method name getBasePath would be more appropriate and meaningful.

[piotr-cz]

@odan This is I was not sure about, as there also are methods like relativeUrlFor and not getRelativeUrlFor.

[odan]

@piotr-cz Ah yes, that's right.

[piotr-cz]

@odan
I've renamed method to getBasePath like you suggested.
It is used in other places in application and different one could confuse people.

[l0gicgate]

This is a BC change since we’re adding onto the interface. @akrabat correct?

[akrabat]

This is a BC change since we’re adding onto the interface. @akrabat correct?

Yes. Ouch.

[piotr-cz]

What about keeping method in implementation without adding it to interface?
We could add it to interface next major version

[piotr-cz]

Superseeded by #2859