在为 NodeSeq 编写自定义匹配器时遇到问题:
private def matchXML(expected: NodeSeq) = new Matcher[NodeSeq] {
def apply(left: NodeSeq): MatchResult = MatchResult(left xml_== expected,
"XML structure was not the same (watch spaces in tag texts)",
"XML messages were equal")
}
这会编译,但下面的代码:
val expected : NodeSeq = ...
val xml : NodeSeq = ...
xml should matchXML(expected)
原因:
error: overloaded method value should with alternatives:
(beWord: XMLStripDecoratorTests.this.BeWord)XMLStripDecoratorTests.this.ResultOfBeWordForAnyRef[scala.collection.GenSeq[scala.xml.Node]] <and>
(notWord: XMLStripDecoratorTests.this.NotWord)XMLStripDecoratorTests.this.ResultOfNotWordForAnyRef[scala.collection.GenSeq[scala.xml.Node]] <and>
(haveWord: XMLStripDecoratorTests.this.HaveWord)XMLStripDecoratorTests.this.ResultOfHaveWordForSeq[scala.xml.Node] <and>
(rightMatcher: org.scalatest.matchers.Matcher[scala.collection.GenSeq[scala.xml.Node]])Unit
cannot be applied to (org.scalatest.matchers.Matcher[scala.xml.NodeSeq])
xml should (matchXML(expected))
任何想法这意味着什么?