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KotlinAssertionUse

Issue ID KotlinAssertionUse · Severity Warning · Category Correctness · Default on

Flags calls to Kotlin's built-in assert(condition) (from kotlin.PreconditionsKt) inside test sources.

Why

kotlin.assert only runs when the JVM is started with -ea (assertions enabled). In a typical test run that flag isn't set, so the call quietly becomes a no-op and the test cannot fail. Even when assertions are enabled, the failure message is just "Assertion failed" — assertk produces descriptive, value-aware messages.

Example

class TestingTesting {
    fun testingTest() {
        val first = File()
        assert(first.canRead) // silently no-ops without -ea
    }
}

import assertk.assertThat
import assertk.assertions.isTrue

class TestingTesting {
    fun testingTest() {
        val first = File()
        assertThat(first.canRead).isTrue()
    }
}

Quick fix

Yes — the IDE rewrites assert(x) to assertThat(x).isTrue() and adds the necessary imports (assertk.assertThat, assertk.assertions.isTrue).

Source

KotlinAssertionDetector.kt