Setup running a UI test project via Gradle integration tests infrastructure

[whyoleg]

After some thoughts I've decided to put UI test project near all other Gradle integration tests because:

• it's easier this way to reuse all the infrastructure that is available for running Gradle and storing it's output
• it will be nice to run at least sanity checks, f.e that ui project builds, produces output and there is no ERROR CLASS and unresolved links there, so that if something is broken during development we will know proactively

Project is now located in dokka-integration-tests/gradle/projects/ui-showcase.
To run UI test and get HTML output (execute in the root of repository):

export DOKKA_TEST_OUTPUT_PATH="build/uiproject"
./gradlew :dokka-integration-tests:gradle:testUiShowcaseProject

output will be located in dokka-integration-tests/gradle/build/uiproject in this specific example;
it's also possible to provide absolute path to DOKKA_TEST_OUTPUT_PATH

The test will use TestedVersions.LATEST for execution.

@berezinant Please check, that this will work fine at your side. Feel free to ask additional questions

[whyoleg]

@adam-enko could you please help. I've added additional integration test and looks like now it's executed in every batch on TC :)

Note: K2 tests are failed because K2 analysis doesn't resolve CPointer - I will mute new test for K2

[adam-enko]

Sure thing @whyoleg! I don't see anything obviously wrong at first glance...

Ah, it's in the docs https://www.jetbrains.com/help/teamcity/cloud/parallel-tests.html#Known+limitations

A newly added test which is not yet known to TeamCity will run in each batch during the first run. Related YouTrack ticket: TW-75913.

I think that's the case here - do you think so too?

[whyoleg]

Thank you! I've checked TC after new commit - and looks like everything is fine now.
Rather surprising limitation :)

[berezinant]

I've tested the new task and it works well for me 👍

As an addition, it also would be nice to have an opportunity generate output on UI showcase project agains specific Dokka's version, it would allow to compare versions quickly and simplify testing and reviewing of PRs

[whyoleg]

it also would be nice to have an opportunity generate output on UI showcase project agains specific Dokka's version

Created separate PR #3585 to not block this one and continue discussion there.

If it's fine, I will merge this one.