Question

I’m using scalatest and want to say

actualXML should be === expectedXML

especially as === doesn’t care about attribute order. However the assertion fails when text has been embedded using Scala XML’s { … } syntax because

scala> <a>b {"c"}</a>.child
res8: scala.xml.Node* = ArrayBuffer(b , c)

whereas:

scala> <a>b c</a>.child
res9: scala.xml.Node* = ArrayBuffer(b c)

I can write a method

import scala.xml.Elem
import scala.xml.XML
def launder(xml: Elem): Elem = XML.loadString(xml.toString)

giving

launder(actualXML) should be === expectedXML

but would like to be able to use the vanilla syntax.

Answer 1

You can introduce your own Equalizer class specifically for Xml Elem:

class ElemEqualizer(left: scala.xml.Elem) {
  def ===(right: Any) = new Equalizer(launder(left).===(launder(right))
}
implicit def convertToElemEqualizer(left: scala.xml.Elem) = new ElemEqualizer(left)

@Test def foobar(): Unit = {
  val a = <a>b {"c"}</a>
  val b = <a>b c</a>

  assert(a === b)
}

So you’re introducing another implicit conversion but this time specifically for Elem, which compares the laundered Elems.