Fix issue with identical cache keys between projects

Fixes #633
PR #636

Author: remcomokveld

kover-gradle-plugin/src/functionalTest/kotlin/kotlinx/kover/gradle/plugin/test/functional/cases/ArtifactGenerationTests.kt

@@ -25,6 +25,20 @@ internal class ArtifactGenerationTests {
         }
     }
 
+    /**
+     * Kover generation tasks compute a cache key based on the content of the relative paths
+     * in their input field. If there are no additional inputs defiend that differentiate task input
+     * between projects then the cache key of the generate tasks in one project is the same as the cache key
+     * in other projects.
+     */
+    @GeneratedTest
+    fun BuildConfigurator.testBuildCacheEntriesAreNotReusedAmongEmptyProjects() {
+        addProjectWithKover { }
+        addProjectWithKover(":project-a", "project-a") {}
+        addProjectWithKover(":project-b", "project-b") {}
+        run("check", "--build-cache") {}
+    }
+
     /**
      * Check that Kover artifact files are not resolved during the task dependency tree construction process.
      *

kover-gradle-plugin/src/main/kotlin/kotlinx/kover/gradle/plugin/tasks/services/KoverArtifactGenerationTask.kt

@@ -42,7 +42,8 @@ internal abstract class KoverArtifactGenerationTask : DefaultTask() {
 
     private val rootDir: File = project.rootDir
 
-    private val projectPath: String = project.path
+    @get:Input
+    internal val projectPath: String = project.path
 
     @TaskAction
     fun generate() {