Gradle test executors use the wrong version of Kotlin stdlib with java-gradle-plugin

[cesar1000]

Expected Behavior

Tests should use the version of Kotlin stdlib declared in the test runtime classpath.

Current Behavior

When applying java-gradle-plugin, tests use Kotlin stdlib 1.3.61 consistently (with Gradle 6.2.2), even if the build is configured to use 1.3.71.

Context

It seems like the application classpath of the test executor worker contains version 1.3.61 of Kotlin stdlib, and that gets picked up at runtime even of the build is configured to use 1.3.71:

The application classpath in the debug logs looks like this:

<test class directories>
~/.gradle/caches/6.2.2/generated-gradle-jars/gradle-api-6.2.2.jar
~/.gradle/wrapper/dists/gradle-6.2.2-bin/1q1x0w9jt7yxk5iea7m897kou/gradle-6.2.2/lib/groovy-all-1.3-2.5.8.jar
~/.gradle/wrapper/dists/gradle-6.2.2-bin/1q1x0w9jt7yxk5iea7m897kou/gradle-6.2.2/lib/kotlin-stdlib-1.3.61.jar
<other gradle dependencies>
<my test runtime classpath>
~/.gradle/caches/modules-2/files-2.1/org.jetbrains.kotlin/kotlin-stdlib/1.3.71/898273189ad22779da6bed88ded39b14cb5fd432/kotlin-stdlib-1.3.71.jar
...

Steps to Reproduce

A Kotlin project with java-gradle-plugin and Kotlin stdlib 1.3.71 would do. Just watch for KotlinVersion.CURRENT in your test.

Your Environment

Gradle 6.2.2 with Kotlin 1.3.71

[ljacomet]

@cesar1000 Thanks for the report.
Any chance you can share a small reproducer?

[cesar1000]

It looks like the issue shows up when using java-gradle-plugin, which seems to skip dependency resolution and insert its own version of Kotlin in the classpath. In this example, the version in the classpath is 1.3.72, but the actual version used at runtime by the test is 1.3.70:

I put up a tiny reproducer here: https://github.com/cesar1000/wrong-kotlin-version.

[stale]

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[stale]

This issue has been automatically closed due to inactivity. If you can reproduce this on a recent version of Gradle or if you have a good use case for this feature, please feel free to to let know so we can reopen the issue. Please try to provide steps to reproduce, a quick explanation of your use case or a high-quality pull request.

[martinbonnin]

I think this is an instance of #1835. java-gradle-plugin pulls gradleApi() and gradleTestKit(). The surprising thing is that they do not appear in ./gradlew dependencies