Codegen tests on Android

This module runs codegen box tests on Android. It discovers eligible tests from:

compiler/testData/codegen/box
compiler/testData/codegen/boxJvm
compiler/testData/codegen/boxInline

The runner compiles the discovered tests into a temporary Android project, builds and installs APKs by flavor, and then runs the tests on an emulator. The emulator and SDK are provisioned on the first run. See CodegenTestsOnAndroidGenerator for the exact exclusions; the main ones are tests annotated with // IGNORE_BACKEND: ANDROID, tests with Java source files, and tests that use unsupported Kotlin/JVM features.

Run the tests via Gradle:

./gradlew :compiler:android-tests:test

The JUnit report is split into phases:

Discovery: finds Android-compatible box tests.
Compilation: compiles discovered tests before the emulator is started.
Emulator: creates and starts the Android emulator.
Runtime: builds, installs, and runs tests grouped by Android flavor.

Useful properties

Property	Description
`kotlin.test.android.path.filter`	Runs only tests whose file path contains this substring. The value is not a regular expression.
`kotlin.test.android.compilation.parallelism`	Limits concurrent test compilation. By default, the runner uses up to 4 workers, capped by available processors. Values lower than 1 are coerced to 1.
`kotlin.test.android.teamcity`	Enables CI behavior outside TeamCity. This disables emulator hardware acceleration and adds extra stabilization delay before install. `-Pteamcity=true` has the same effect.
`kotlin.test.android.avd.systemImage`	Overrides the Android system image package passed to `avdmanager` when creating the AVD. The image must be available in the provisioned SDK.

Run a small subset by path:

./gradlew :compiler:android-tests:test -Pkotlin.test.android.path.filter=dontReify

Run one file and force sequential compilation:

./gradlew :compiler:android-tests:test \
  -Pkotlin.test.android.path.filter=arrayWrite.kt \
  -Pkotlin.test.android.compilation.parallelism=1

Increase compilation parallelism on a machine with enough memory (default is 4):

./gradlew :compiler:android-tests:test -Pkotlin.test.android.compilation.parallelism=8

On TeamCity we run emulator without hardware acceleration. Force TeamCity-like emulator behavior locally:

./gradlew :compiler:android-tests:test -Pkotlin.test.android.teamcity=true

Use a specific Android system image:

./gradlew :compiler:android-tests:test \
  "-Pkotlin.test.android.avd.systemImage=system-images;android-26;default;x86_64"