JarCastingkotlin-power-assert
Kotlin Compiler Plugin which high-jacks Kotlin assert function calls and transforms them similar to Groovy's Power Assert feature. This plugin uses the IR backend for the Kotlin compiler and supports all platforms: JVM, JS, and Native!
Example
Given following code:
val hello = "Hello"
assert(hello.length == "World".substring(1, 4).length)
Normally the assertion message would look like:
java.lang.AssertionError: Assertion failed
at <stacktrace>
A custom assertion message can be provided:
val hello = "Hello"
assert(hello.length == "World".substring(1, 4).length) { "Incorrect length" }
But this just replaces the message:
java.lang.AssertionError: Incorrect length
at <stacktrace>
With kotlin-power-assert included, the error message for the previous example will be transformed:
java.lang.AssertionError: Incorrect length
assert(hello.length == "World".substring(1, 4).length)
| | | | |
| | | | 3
| | | orl
| | false
| 5
Hello
at <stacktrace>
Complex, multi-line, boolean expression are also supported:
Assertion failed
assert(
(text != null && text.toLowerCase() == text) ||
| |
| false
null
text == "Hello"
| |
| false
null
)
Gradle Plugin
Builds of the Gradle plugin are available through the Gradle Plugin Portal.
plugins {
kotlin("multiplatform") version "1.4.20"
id("com.bnorm.power.kotlin-power-assert") version "0.6.1"
}
The plugin by default will transform assert function call but can also transform other functions like require, check, and/or assertTrue. The function needs to validate the Boolean expression evaluates to true and has a form which also takes a String or String producing lambda.
configure<com.bnorm.power.PowerAssertGradleExtension> {
functions = listOf("kotlin.assert", "kotlin.test.assertTrue")
}
Kotlin IR
Using this compiler plugin only works if the code is compiled using Kotlin 1.4.20 and IR is enabled. This includes all IR based compiler backends: JVM, JS, and Native! As Kotlin IR is still experimental, mileage may vary.
Kotlin/JVM
tasks.withType<KotlinCompile>().configureEach {
kotlinOptions {
useIR = true
}
}
Kotlin/JS
target {
js(IR) {
}
}
Kotlin/Native
IR already enabled by default!