Use variants dynamically to put sourceSets

[tasomaniac]

Instead of resolving sourceSets from extension, resolve variants and use the sources defined in there.

Fixes #153

[tasomaniac]

This ext.variants is coming from the PluginUtils.

Here all makes it lazy loop over variants. When a variant is created, it is sourceSet is also set and contains all directories.

[JLLeitschuh]

Is there any good way to add a unit test for this?

[tasomaniac]

Ktlint integration with a Kotlin project is tested already in the repo. The same should be done for an Android project too. We have some tests in Novoda plugin, I used those test to double check these changes.

https://github.com/novoda/gradle-static-analysis-plugin/blob/develop/plugin/src/test/groovy/com/novoda/staticanalysis/internal/ktlint/KtlintIntegrationTest.groovy

If a setup is done, I would be happy to contribute to tests.

[JLLeitschuh]

@Tapchicoma Can unit tests against android be written or would that couple our test infrastructure to requiring the Android SDKs to be installed?

[tasomaniac]

As @Tapchicoma mentioned, this extension is not available on InstantApp modules. Don't really know what to do in this case.

[JLLeitschuh]

Can you elaborate on what the problem is?
I'm not an Android developer. Hahah.

[tasomaniac]

Android have multiple plugins. In KtlintPlugin.kt class where we configure the Android plugin, we support InstantApp modules. But here, unfortunately we cannot access the variants in InstantAppExtension because it is not visible for some reason.

I've done this a lot of times but I never supported instant app plugin before. Not sure what to do in this case.

[Tapchicoma]

@tasomaniac thank you for your contribution!

As we discussed in #153 and #170 - can you update your PR:
Instead of creating check task for all android variant sources, create a meta task per variant (adding Variant for a task name - for example, ktlintKellerbierDebugVariantCheck) and include a dependency on specific source set task. As far, as I see from your PR, it will be possible to do, just need to extract source set check and format tasks name creation based on SourceSet name and use it, when declaring dependency on check (format) task.

[tasomaniac]

Hey, I believe that would be the best. But I need to start from scratch to do that. I will just close this so anybody can take it.

[Tapchicoma]

@tasomaniac I think, I will approach this after #180 will be merged 👍

[tasomaniac]

Thanks @Tapchicoma