我有以下方法：
def save(entity: A): Either[List[Error],A] + {....
我想用specs2测试
我想在未指定必填字段时测试是否存在特定错误,如下所示：
val noNickname = User(
nickname = "",name = "new name",)
noNickname.save must beLeft.like {
case errors => {
atLeastOnceWhen(errors) {
case error => {
error.errorCode must equalTo(Error.required)
error.field must equalTo("nickname")
}
}
}
}
它工作正常,但我想定义自己的匹配器,使其更简洁,像这样：
noNickname.save must haveError.like {
case error => {
error.errorCode must equalTo(Error.required)
error.field must equalTo("nickname")
}
}
}
我查看了文档(http://etorreborre.github.com/specs2/guide/org.specs2.guide.Matchers.html#Matchers),但我无法弄清楚如何定义像hasError这样的自定义匹配器.喜欢
解决方法
这里你的代码有一些改动,使它编译：
case class Error(errorCode: String,field: String)
def save[A](entity: A): Either[List[Error],A] = Left(List(Error("required","nickname")))
case class User(nickname: String,name: String)
val noNickname = User(nickname = "",name = "new name")
"save noNickName" >> {
save(noNickname) must haveError.like {
case error => {
error.errorCode must equalTo("required")
error.field must equalTo("nickname")
}
}
}
def haveError[T] = new ErrorMatcher[T]
class ErrorMatcher[T] extends Matcher[Either[List[T],_]] {
def apply[S <: Either[List[T],_]](value: Expectable[S]) =
result(value.value.left.toOption.isDefined,value.description + " is Left",value.description + " is not Left",value)
def like[U](f: PartialFunction[T,MatchResult[U]]) =
this and partialMatcher(f)
private def partialMatcher[U](f: PartialFunction[T,MatchResult[U]]) =
new Matcher[Either[List[T],_]] {
def apply[S <: Either[List[T],_]](value: Expectable[S]) = {
// get should always work here because it comes after the "and"
val errors = value.value.left.toOption.get
val res = atLeastOnceWhen[T,U](errors)(f)
result(res.isSuccess,value.description+" is Left[T] and "+res.message,value.description+" is Left[T] but "+res.message,value)
}
}
}
请注意,匹配器在[List [T],_]到处定义.
我也想知道在没有找到预期的错误消息的情况下返回的失败消息,当部分函数失败时它们可能不是非常明确.
所以你可能想要使用包含匹配器.像这样：
"save noNickName" >> {
save(noNickname) must haveError.containing(Error("required","nickname"))
}
// I'm reusing the beLeft matcher here
def haveError[T]: Matcher[Either[List[T],_]] = beLeft
// and using an implicit conversion to extend it
implicit def toErrorListMatcher[T](m: Matcher[Either[List[T],_]]): ErrorListMatcher[T] =
new ErrorListMatcher[T](m)
class ErrorListMatcher[T](m: Matcher[Either[List[T],_]]) {
def containing(t: T) =
// the 'contain' matcher is adapted to take in an
// Either[List[T],_] and work on its left part
m and contain(t) ^^ ((e: Either[List[T],_]) => e.left.toOption.get)
}
[更新]
第一个解决方案(使用atLeastOnceWhen和部分函数)可以与第二个解决方案(使用隐式)和beLike匹配器组合,以获得现有规范2代码的最大可重用性：
def haveError[T]: Matcher[Either[List[T],_] = beLeft
implicit def toErrorListMatcher[T](m: Matcher[Either[List[T],_]]): ErrorListMatcher[T] =
new ErrorListMatcher[T](m)
class ErrorListMatcher[T](m: Matcher[Either[List[T],_]]) {
// beLike checks one element
// beLike.atLeastOnce transforms that matcher on a
// matcher on a sequence of elements
def like[S](f: PartialFunction[T,MatchResult[S]]) = {
m and beLike(f).atLeastOnce ^^ ((e: Either[List[T],_]) => e.left.toOption.get)
}
