Run the attached spec to see the problem.

must have size(2) produces a:

java.util.NoSuchElementException: head of empty list

While must haveSize(2) produces:

[error] /Users/Shadowfiend/openstudy/openstudy- scala/src/test/scala/com/openstudy/snippet/HelloWorldTest.scala:18: ambiguous implicit values: [error] both method anyToList in trait Products of type TList[T] [error] and method identity in object Predef of type AA [error] match expected type (scala.xml.Group) => AnyRef{def size: Int} [error] Group(<test></test><secondtest></secondtest>) must haveSize(2)

To get the spec to run correctly, I had to call toList on the NodeSeq, but I got the feeling that it should work without that.

Hi,

Which version of specs are you using?

I could not reproduce the NoSuchElementException with any of 1.6.2 (scala 2.7.7) or with 1.6.3 (scala 2.8.0)

On the other hand I can tell you that the compilation error is due to the import of the Sugar object implicits. In that object there is a function to transform all tuples to a list, including a single element. This conflicts here with the identity method in Predef. If you remove that you should have to call toList on the NodeSeq.

Hm. I figured that the compilation error was due to something similar. I'm obviously a slight bit of a newb to Scala, but isn't it smart enough to figure out that haveSize(2) is a method call, rather than the creation of a tuple? Silly question, of course: obviously, it isn't :-P

I'm running specs 1.6.2 with scala 2.7.7. This wouldn't have anything to do with running through sbt, would it?

Further analysis on the NoSuchElementException shows that you've been bitten (my fault certainly) by implicits.

Since there is a method in the Sugar object to convert anything to a List. If I write:

val x = Group() must have

then x is of type org.specs.specification.Result[Group] and converted to a List, it has a size method. Which returns an Integer, which is converted to a list of one element again, and then fails when trying to get the element at position 2.

I fixed the issue anyway and the fix is available in specs-1.6.2.1-SNAPSHOT:

http://nexus-direct.scala-tools.org/content/repositories/snapshots/org/scala- tools/testing/specs/1.6.2.1-SNAPSHOT/specs-1.6.2.1-SNAPSHOT.jar.

Wow, complicated hehe.

So wait, what eventually helped to reproduce it?