StreamlinedXml

Trait providing a streamlined method that returns a Uniformity[T] instance for any subtype of scala.xml.NodeSeq that will normalize the XML by removing empty text nodes and trimming non-empty text nodes.

Here's an example of some unnormalized XML:

<summer>
 <day></day>
 <night>
   with lots of stars
 </night>
</summer>

The Uniformity returned by this trait's streamlined method would transform the above XML to:

<summer><day></day><night>with lots of stars</night></summer>

The streamlined method can be used with the Explicitly DSL, like this:

xmlElem should equal (
 <summer>
   <day></day>
   <night>
     with lots of stars
   </night>
 </summer>
) (after being streamlined[Elem])

The goal of this trait is to provide a normalization for XML that makes it easier to test XML objects for equality. White space is significant in XML, and is taken into account by the default equality for XML, accessed by invoking the == method on an XML NodeSeq. Here's an example:

scala> val xmlElem = <summer><day></day><night>with lots of stars</night></summer>
xmlElem: scala.xml.Elem = <summer><day></day><night>with lots of stars</night></summer>

scala> xmlElem == <summer>
    |   <day></day>
    |   <night>
    |     with lots of stars
    |   </night>
    | </summer>
res1: Boolean = false

The above equality comparison produces false because of whitespace differences in the XML. When such whitespace differences are unimportant to the actual application, it can make it easier to write readable test code if you can compare XML for equality without taking into account empty text nodes, or leading and trailing whitespace in nonempty text nodes. The streamlined method of this trait provides a Uniformity instance that does just that:

scala> import org.scalactic._
import org.scalactic._

scala> import Explicitly._
import Explicitly._

scala> import TripleEquals._
import TripleEquals._

scala> import org.scalatest.StreamlinedXml._
import StreamlinedXml._

scala> import scala.xml.Elem
import scala.xml.Elem *

scala> (xmlElem === <summer>
    |   <day></day>
    |   <night>
    |     with lots of stars
    |   </night>
    | </summer>) (after being streamlined[Elem])
res9: Boolean = true