Assertion Mode

If you are using Kotest framework alongside Kotest assertions, you can ask Kotest to fail the build, or output a warning to stderr, if a test is executed that does not execute an assertion.

To do this, set assertionMode to AssertionMode.Error or AssertionMode.Warn inside a spec. For example.

class MySpec : FunSpec() {
init {
assertions = AssertionMode.Error
test("this test has no assertions") {
val name = "sam"
name.length == 3 // this isn't actually testing anything

Running this test will output something like:

Test 'this test has no assertions' did not invoke any assertions

If we want to set this globally, we can do so in project config or via the system property kotest.framework.assertion.mode.


Assertion mode only works for Kotest assertions and not other assertion libraries.