IntelliJ Plugin with AOSP inserts incorrect blank lines during optimize imports

レポートに示されているAOSPスタイルのJavaインポートに対してOptimize Importsを実行し、IntelliJプラグインで問題を再現してから、結果をSpotlessおよびGoogle Java Style Guideと比較します。プラグインのAOSPインポート順序付けの動作を追跡します。Optimize Importsで期待される空行だけが残り、デフォルトのGOOGLEスタイルに影響がなければ完了です。

When using the IntelliJ google-java-formatter 1.16.0.2 with the AOSP style, the "Optimize Imports" action results in empty lines between imports with different TLDs.

Given:

// ...
import static org.assertj.core.api.Assertions.assertThat;
import lombok.extern.slf4j.Slf4j;
import org.junit.jupiter.params.ParameterizedTest;
import java.io.ByteArrayOutputStream;
import java.io.FileInputStream;
// ...

Results in:

// ...
import static org.assertj.core.api.Assertions.assertThat;

import lombok.extern.slf4j.Slf4j;

import org.junit.jupiter.params.ParameterizedTest;

import java.io.ByteArrayOutputStream;
import java.io.FileInputStream;
// ...

Expected:

When using spotless:check with google-java-formatter 0.16.0 / 0.17.0 and AOSP, it complains that all but the first empty line have to be removed. The online documentation seems to agree with spotless.

The IntelliJ plugin does not break the Google Java Style Guide when executing "optimize imports".

Context

This being inconsistent between spotless and Intellij is very inconvenient. We use use spotless in the CI to enforce the codestyle and this necessitates running mvn spotless:apply for every commit or disabling "optimize imports" which itself results in manual cleanup of unused imports.

I have tried it with the default GOOGLE style and that does not seem to have this problem.