Fix incompatibility with JUnit 6 in OSGi environment

Change the VersionRange of JUnit platform to support JUnit 6.

Fixes #2231

Author: AndreasTu

docs/release_notes.adoc

@@ -58,6 +58,7 @@ will now require that the spec is annotated with <<parallel_execution.adoc#isola
 === Misc
 
 * Fix vararg handling in SpyStatic spockIssue:2161[]
+* Fix incompatibility with JUnit 6 in OSGi environment spockIssue:2231[]
 
 == 2.4-M6 (2025-04-15)
 

gradle/libs.versions.toml

@@ -5,6 +5,8 @@ groovy3 = '3.0.25'
 groovy4 = '4.0.29'
 jacoco = '0.8.14'
 junit = '5.14.0'
+# The VersionRange used by OSGi to check compatibility with JUnit Platform.
+junitPlatformVersionRange = "[1.12,7)"
 asm = '9.9'
 mockito4 = '4.11.0'
 mockito5 = '5.20.0'

spock-core/core.gradle

@@ -60,11 +60,18 @@ tasks.named("jar", Jar) {
       'Automatic-Module-Name': 'org.spockframework.core'
     )
   }
+
+  String junitPlatformVersionRange = libs.versions.junitPlatformVersionRange.get()
+
   bundle {
     bnd(
       'Export-Package': ['org.spockframework.*', 'spock.*'].join(','),
       'Import-Package': [
-        'org.junit.platform.testkit.*;resolution:=optional',
+        /* We need to override the OSGi version for JUnit platform here, otherwise the version range would be [1.12,2)
+         * which would exclude JUnit 6 in the OSGi case. Note: JUnit Platform changed the versioning from 1.x to 6.x.
+         */
+        "org.junit.platform.testkit.*;resolution:=optional;version=\"$junitPlatformVersionRange\"",
+        "org.junit.platform.*;version=\"$junitPlatformVersionRange\"",
         'org.hamcrest.*;resolution:=optional',
         'org.objenesis.*;resolution:=optional',
         'net.bytebuddy.*;resolution:=optional',