kotlin-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 new IR backend for the Kotlin compiler.

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>