Set junit as Automatic-Module-Name in standalone JAR

[sormuras]

Running jar --describe-module --file junit-platform-console-standalone-X.Y.Z.jar yields:

No module descriptor found. Derived automatic module.

[email protected] automatic
requires java.base mandated
provides java.util.spi.ToolProvider with org.junit.platform.console.ConsoleLauncherToolProvider
provides org.junit.platform.engine.TestEngine with [...]JupiterTestEngine [...]SuiteTestEngine [...]VintageTestEngine
provides org.junit.platform.launcher.TestExecutionListener with [...]UniqueIdTrackingListener [...]OpenTestReportGeneratingListener
contains junit.extensions
contains junit.framework
contains junit.runner
contains junit.textui
contains org.apiguardian.api
contains org.hamcrest
contains org.hamcrest.core
contains org.hamcrest.internal
contains org.junit
contains org.junit.experimental
contains org.junit.experimental.categories
[...]
contains org.junit.vintage.engine.support
contains org.opentest4j
main-class org.junit.platform.console.ConsoleLauncher

The name of the derived automatic module is based on the file name - which is unstable if users or build tools rename the JAR file. It would be better to provide a stable name in the JAR's manifest for when the standalone JAR is put on the module path. As this JUnit Platform standalone JAR is often used as a drop-in replacment for JUnit 3/4, the automatic module name should be junit - just as the junit.jar has it since 2018 via:

• Set 'junit' as Automatic-Module-Name junit4#1571

[sormuras]

With

Index: junit-platform-console-standalone/junit-platform-console-standalone.gradle.kts
IDEA additional info:
Subsystem: com.intellij.openapi.diff.impl.patch.CharsetEP
<+>UTF-8
===================================================================
diff --git a/junit-platform-console-standalone/junit-platform-console-standalone.gradle.kts b/junit-platform-console-standalone/junit-platform-console-standalone.gradle.kts
--- a/junit-platform-console-standalone/junit-platform-console-standalone.gradle.kts	(revision 35d3dd71662beda795e3ce3c428b9a1215d8c9e4)
+++ b/junit-platform-console-standalone/junit-platform-console-standalone.gradle.kts	(date 1729247166506)
@@ -25,6 +25,7 @@
 tasks {
 	jar {
 		manifest {
+			attributes("Automatic-Module-Name" to "junit")
 			attributes("Main-Class" to "org.junit.platform.console.ConsoleLauncher")
 		}
 	}

applied, we'd get for jar --describe-module --file junit-platform-console-standalone-1.12.0-SNAPSHOT.jar:

No module descriptor found. Derived automatic module.

[email protected] automatic
[...]

[marcphilipp]

junit is already used as automatic module name for JUnit 4 so I don't think we should use it for the console launcher:

https://github.com/junit-team/junit4/blob/ed47b7f487bafa48cff47f051af81a004cd36049/pom.xml#L361

[sormuras]

Are you thinking about name clashes in cases where both artifacts (junit.jar and junit-platform-console-standalone.jar) land on the module path?

[marcphilipp]

Yes, which happens as soon as one uses the Vintage engine. Moreover, it "feels wrong".

[sbrannen]

I agree with Marc. We should not use junit as the automatic module name for the standalone console launcher artifact for two reasons.

1. It's already used by JUnit 4.
2. Even if it were not used by JUnit 4, the console launcher is not "JUnit".

[marcphilipp]

@sormuras Ok to close this?

[sormuras]

Yes.

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