exception - Spock - 使用数据表测试异常

Question

如何使用 Spock 以良好的方式(例如数据表)测试异常？

示例:有一个方法 validateUser 可以抛出不同消息的异常，或者如果用户有效则不抛出异常。

规范类本身:

class User { String userName }

class SomeSpec extends spock.lang.Specification {

    ...tests go here...

    private validateUser(User user) {
        if (!user) throw new Exception ('no user')
        if (!user.userName) throw new Exception ('no userName')
    }
}

变体 1

这个是可行的，但真正的意图被所有的 when/then 标签和 validateUser(user) 的重复调用弄得一团糟.

    def 'validate user - the long way - working but not nice'() {
        when:
        def user = new User(userName: 'tester')
        validateUser(user)

        then:
        noExceptionThrown()

        when:
        user = new User(userName: null)
        validateUser(user)

        then:
        def ex = thrown(Exception)
        ex.message == 'no userName'

        when:
        user = null
        validateUser(user)

        then:
        ex = thrown(Exception)
        ex.message == 'no user'
    }

变体 2

由于 Spock 在编译时引发的这个错误，这个无法工作:

异常条件只允许出现在“then” block 中

    def 'validate user - data table 1 - not working'() {
        when:
        validateUser(user)

        then:
        check()

        where:
        user                         || check
        new User(userName: 'tester') || { noExceptionThrown() }
        new User(userName: null)     || { Exception ex = thrown(); ex.message == 'no userName' }
        null                         || { Exception ex = thrown(); ex.message == 'no user' }
    }

变体 3

由于 Spock 在编译时引发的这个错误，这个无法工作:

异常条件只允许作为顶级语句

    def 'validate user - data table 2 - not working'() {
        when:
        validateUser(user)

        then:
        if (expectedException) {
            def ex = thrown(expectedException)
            ex.message == expectedMessage
        } else {
            noExceptionThrown()
        }

        where:
        user                         || expectedException | expectedMessage
        new User(userName: 'tester') || null              | null
        new User(userName: null)     || Exception         | 'no userName'
        null                         || Exception         | 'no user'
    }

Answer 1

推荐的解决方案是有两种方法:一种测试好的情况，另一种测试坏的情况。那么这两种方法都可以利用数据表。

例子:

class SomeSpec extends Specification {

    class User { String userName }

    def 'validate valid user'() {
        when:
        validateUser(user)

        then:
        noExceptionThrown()

        where:
        user << [
                new User(userName: 'tester'),
                new User(userName: 'joe')]
    }

    def 'validate invalid user'() {
        when:
        validateUser(user)

        then:
        def error = thrown(expectedException)
        error.message == expectedMessage

        where:
        user                     || expectedException | expectedMessage
        new User(userName: null) || Exception         | 'no userName'
        new User(userName: '')   || Exception         | 'no userName'
        null                     || Exception         | 'no user'
    }

    private validateUser(User user) {
        if (!user) throw new Exception('no user')
        if (!user.userName) throw new Exception('no userName')
    }

}