test: Use kotest

src/main/kotlin/util/JvmUtil.kt

@@ -0,0 +1,32 @@
+package moe.nea.firmament.util
+
+import com.sun.tools.attach.VirtualMachine
+import java.lang.management.ManagementFactory
+import java.nio.file.Path
+import kotlin.io.path.absolutePathString
+
+object JvmUtil {
+	fun guessJVMPid(): String {
+		val name = ManagementFactory.getRuntimeMXBean().name
+		val pid = name.substringBefore('@')
+		ErrorUtil.softCheck("Not a valid PID: $pid", pid.toIntOrNull() != null)
+		return pid
+	}
+
+	fun getVM(): VirtualMachine {
+		return VirtualMachine.attach(guessJVMPid())
+	}
+
+	fun useVM(block: (VirtualMachine) -> Unit) {
+		val vm = getVM()
+		block(vm)
+		vm.detach()
+	}
+
+	fun loadAgent(jarPath: Path, options: String? = null) {
+		useVM {
+			it.loadAgent(jarPath.absolutePathString(), options)
+		}
+	}
+
+}