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kotlinlang

Hey, why is shouldBe (and its friends) not generically typed? Isn't the same the type the prerequisite for the values being equal? This would ease writing tests I think. Currently I need to figure type mismatches at runtime and not compile time.

IIRC it's due to some corner cases, like `listOf(1,2,3) shouldBe intArrayOf(1,2,3)`

I tinkered with a code inspection in the Kotest IntelliJ plugin way back, which identified cases where incompatible types were being passed to `shouldBe` <https://github.com/kotest/kotest-intellij-plugin/pull/146>

Even if this fails for collections, what about simple objects? I'm thinking about:
`val foo= 1.3`
`foo shouldBe 2`

Does this really require a plugin? I was hoping for some simple (possibly reified) generic flavor of shouldBe.

From what I understand after some discussion with chatgpt, this currently not possible because of type earsure.

Type erasure only occurs during runtime. I don’t think that’s a factor here

It doesn't work for:
`apple shouldBe fruit` and `fruit shouldBe apple`

I think kotlin.test solves that with `@OnlyInputTypes T`, though the annotation's internal to Kotlin at the moment. (<https://github.com/JetBrains/kotlin/blob/0938b46726b9c6938df309098316ce741815bb55/libraries/kotlin.test/common/src/main/kotlin/kotlin/test/Assertions.kt#L62|here>)

Would that work for A, B if A &lt;: B as well as A &gt;: B because that's the usecase we need.

If it just locks in the types, it won't work where one is a subtype of another.