Simultaneous test generation crashes one of them

[Domonion]

Description

In IDEA it is possible to run multiple test generation processes simultaneously. Only one succeedes and it is unpredictable which one.

To Reproduce

Steps to reproduce the behavior:

1. Create empty console project with Java 8/11
2. Create file RandomClass.kt with following content:

class RandomClass {
    fun functionToTest(a: Int, b: Double): String {
        val c = 100 / a + b
        return c.toString()
    }
}

3. Create file DateExample.kt with following content:

import java.util.*

class DateExample {
    fun getTime(date: Date): Boolean {
        return date.time == 100L
    }
}

4. Open each file in separate editor instance
5. Generate test for each with Alt+Shift+U shortcut

Expected behavior

Tests are supposed to be generated.

Actual behavior

Only one test is generated, another one shows following error:

Visual proofs (screenshots, logs, images)

java_hyoQnboBEE.mp4

Additional context

1. Only 1 error log file is created, so it means that in case of simultaneous generation one of processes does not even reach concrete executor
2. idea.log does not contain nor exceptions nor useful information

Files
Project - untitled.zip