compare mapping against parent if it exists

[nfcampos]

• basically just compares new mappings against the parent (if it exists). only goes one level deep so if you have

{
  foo: {
    url: '/foo',
    then: () => ({
      url: '/then',
      then: () => ({
        url: '/thenthen'
      })
    })
  }
}

it'll still be broken

• missing a test for this, don't merge yet

closes #102

what do you think of this solution @ryanbrainard ?

[ryanbrainard]

Hmm...yeah, I think that'll work. Might need to think on it. Also, maybe parent should always be the top-level mapping as to work in cases with multi-level chains?

[nfcampos]

Yeah I agree parent should always be the top level mapping

[nfcampos]

the cleanest way to do that is to save a reference to parent (if it exists) in each mapping, inside coerceMapping, any reason not to do that?
like this:

[ryanbrainard]

Seems like that should work

[ryanbrainard]

Thanks!