Hello everyone! I have the following data structure: ```data class User( val id: String, val...

# kotest

[Philipp Mayer]

Hello everyone!
I have the following data structure:

data class User(
    val id: String,
    val someTime: LocalDateTime,
    val someDetails: SomeDetails,
) {
    data class SomeDetails(
        val otherId: String,
        val otherTime: LocalDateTime,
    )
}

val user = User(
    id = "1",
    someTime = LocalDateTime.now(),
    someDetails = User.SomeDetails(
        otherId = "a",
        otherTime = LocalDateTime.now().plusSeconds(1)
    )
)
val otherUser = User(
    id = "1",
    someTime = LocalDateTime.now().plusHours(1),
    someDetails = User.SomeDetails(
        otherId = "a",
        otherTime = LocalDateTime.now().plusSeconds(22)
    )
)

I would like to write a test that ignores both LocalDateTime fields.
Something in the lines of:

class SomeTest {
    @Test
    fun `should ignore localdatetime fields`() {
        user.shouldBeEqualToIgnoringFields(otherUser, User::someTime, User.SomeDetails::otherTime)
    }
}

Is there any matcher that I might have missed when going through the docs?
Thanks in advance!

[thanksforallthefish]

I might miss something as well, but I usually with

user should {
  check one by one
}

an alternative is withConstantNow

"test" {
  withConstantNow(LocalDateTime.now()) {
    user shouldBe otherUser
  }
}

withConstantNow fixes a point in time and all LocalDateTime.now would return always the same value (so no need to ignore those anymore)

[Philipp Mayer]

I’m unfortunately only using the kotest assertions - but this is again an example of why I should introduce the testing framework also to our team. 😁
I didn’t want to do something like

user.asClue {
  ..comparing all properties..
}

because if I add a property later on it’ll not be reflected in the tests.

[thanksforallthefish]

there are ways around the localdate issue. usually you want to have a Clock object, that is an interface and you mock it as well

"test" {
  User(Clock.fixed("fixed time"))
}

data class User(private val clock: Clock) {
  val date = LocalDateTime.now(clock)
}

in general using a clock is suggested anyway

[LeoColman]

There is that matcher exactly, isn't it?

[LeoColman]

https://kotest.io/docs/assertions/core-matchers.html
"Field by Field Comparison Matchers"

[LeoColman]

and Selective Matchers

[LeoColman]

Or do you mean only LocalDateTime field specifically?