Hmmmm JVM tests work, but WasmJS fails

./gradlew :kotest-assertions:kotest-assertions-core:wasmJsTest --stacktrace

[...]

Disconnected (0 times) , because no message in 30000 ms.
java.lang.IllegalStateException: command '/Users/dev/.local/state/gradle/nodejs/node-v22.0.0-darwin-arm64/bin/node' exited with errors (exit code: 1)

> Task :kotest-assertions:kotest-assertions-core:allTests FAILED

Seems like wasmJsBrowserTest fails with a single test exceeding the (presumably karma) timeout of 30 seconds. I could take a look cannot promise results today.

I found a similar issue on Slack https://slack-chats.kotlinlang.org/t/18859293/is-there-special-config-required-to-run-tests-with-wasmjs-i-, but the suggested workaround didn't help https://youtrack.jetbrains.com/issue/KT-67468

I got some help and we figured out the problem: the Kotest Gradle Plugin isn't applied to Kotest projects, so the tests can't be discovered or launched.

Why does this lead to the timeout? I'd expect it the test run to finish on wasmJsBrowserTest without reporting any test. I'll try to investigate,

The test times out because the dependency implementation(projects.kotestFramework.kotestFrameworkEngine) is missing in commonTest. For Wasm, the function startUnitTests is missing in that case:

The Kotlin test framework crashes as it tries to call the function on the headless browser before it could launch the test framework. Karma loses its patience and complains after 30 seconds without any response.

Thanks @OliverO2! However, the tests need testCoroutineScheduler, and I think this isn't available on Wasm yet? #4077

That's correct, any JS platform test (including wasmJs) would fail if it requires a runTest invocation.

Kotest effectively does not fully self-test on non-JVM targets anyway due to the missing Kotest compiler plugin. While it appears to run non-JVM tests, without the plugin in place, test discovery actually does not take place.

This could be corrected, but would require our build scripts to use the build's own version of the Kotest compiler plugin. A previous compiler plugin version from a repo could be chosen, but this would be unstable in case of incompatible changes in the code generated by the plugin.