Platform (all, jvm, js): all
Extension (none, kotlin 1.3): none

Code related feature

expect("test").notToBeAnInstanceOf<Throwable>()

Following the things you need to do:

logic

• extend AnyAssertions with a function notToBeAnInstanceOf (see AnyAssertions.toBe as a guideline)
• implement notToBeAnInstanceOf in DefaultAnyAssertions.kt (see DefaultAnyAssertions toBe)

api-fluent

• provide the fun notToBeAnInstanceOf anyExpectations.kt (see anyExpectations.kt toEqual and toBeAnInstanceOf as a guideline)
  • add NOT_TO_BE_THE_INSTANCE_OF to DescriptionAnyExpectation en_GB
  • add NOT_TO_BE_THE_INSTANCE_OF to DescriptionAnyExpectation de_CH, use "ist nicht eine Instanz vom Typ"
• add @since 1.1.0 (adapt to current milestone) to KDOC
• extend AnyExpectationsSpec in specs -> commonMain and modify it in atrium-api-fluent-en_GB -> commonTest accordingly

api-infix

• provide the fun notToBeAnInstanceOf which returns Expect<T> in anyExpectations.kt (see anyExpectations.kt toEqual and toBeAnInstanceOf as a guideline)
• add @since 1.1.0 (adapt to current milestone) to KDOC
• modify atrium-api-infix-en_GB -> commonTest accordingly

Your first contribution?

• Write a comment I'll work on this if you would like to take this issue over.
  This way we get the chance to revise the description in case things have changed in the meantime, we might give you additional hints and we can assign the task to you, so that others do not start as well.
• See Your first code contribution for guidelines.
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