Grails: Run tests as Unit tests doesn't run Grails 2.* tests (with mixins)

**Build 122.728, Grails 2.1.0**

Get two controllers: HelloController and Hello2Controller with corresponding tests:
```
package test

import grails.test.mixin.*

@TestFor(HelloController)
class HelloControllerTests {
void testSomething() {
fail "Implement me"
}
}
```
```
package test

class Hello2ControllerTests extends GroovyTestCase {
void testSomething() {
fail "Implement me"
}
}
```
Run all tests in package 'test' as Unit tests. Only Hello2ControllerTests will be executed.
HelloControllerTests test is executed when run alone, however.

---

*Imported from [IDEA-94269](https://youtrack.jetbrains.com/issue/IDEA-94269) · Type: Bug · Votes: 4*
*Comments, attachments, dates and reporter are not part of the export — follow the link above for the full history.*

Reproduce the issue with Grails 2.1.0 using HelloControllerTests and Hello2ControllerTests in package test, then inspect the IntelliJ test-discovery entry point for running all tests as Unit tests. Compare discovery of the @TestFor mixin test with the GroovyTestCase test; done means both tests execute when the package is run, while the mixin test still runs alone.

Written by the indexing model from the issue text.