Don't get BuildScanExtension when buildScan report is disabled

#KT-59589: Fixed

(cherry picked from commit ea8b482)

Author: nav-nav

libraries/tools/kotlin-gradle-plugin/src/common/kotlin/org/jetbrains/kotlin/gradle/plugin/statistics/BuildFlowService.kt

@@ -19,6 +19,8 @@ import org.gradle.util.GradleVersion
 import org.jetbrains.kotlin.gradle.plugin.BuildEventsListenerRegistryHolder
 import org.jetbrains.kotlin.gradle.plugin.StatisticsBuildFlowManager
 import org.jetbrains.kotlin.gradle.plugin.internal.isProjectIsolationEnabled
+import org.jetbrains.kotlin.gradle.report.BuildReportType
+import org.jetbrains.kotlin.gradle.report.reportingSettings
 import org.jetbrains.kotlin.gradle.utils.isConfigurationCacheAvailable
 import org.jetbrains.kotlin.statistics.metrics.BooleanMetrics
 import org.jetbrains.kotlin.statistics.metrics.IStatisticsValuesConsumer
@@ -56,6 +58,7 @@ internal abstract class BuildFlowService : BuildService<BuildFlowService.Paramet
             }
 
             val fusStatisticsAvailable = fusStatisticsAvailable(project.gradle)
+            val buildScanReportEnabled = reportingSettings(project).buildReportOutputs.contains(BuildReportType.BUILD_SCAN)
 
             //Workaround for known issues for Gradle 8+: https://github.com/gradle/gradle/issues/24887:
             // when this OperationCompletionListener is called services can be already closed for Gradle 8,
@@ -80,7 +83,7 @@ internal abstract class BuildFlowService : BuildService<BuildFlowService.Paramet
                         else -> StatisticsBuildFlowManager.getInstance(project).subscribeForBuildResult()
                     }
                 }
-                if (GradleVersion.current().baseVersion >= GradleVersion.version("8.1")) {
+                if (buildScanReportEnabled && GradleVersion.current().baseVersion >= GradleVersion.version("8.1")) {
                     StatisticsBuildFlowManager.getInstance(project).subscribeForBuildScan(project)
                 }
             }

libraries/tools/kotlin-gradle-plugin/src/common/kotlin/org/jetbrains/kotlin/gradle/report/BuildMetricsService.kt

@@ -231,44 +231,60 @@ abstract class BuildMetricsService : BuildService<BuildMetricsService.Parameters
         }
 
         private fun subscribeForTaskEvents(project: Project, buildMetricServiceProvider: Provider<BuildMetricsService>) {
-            // BuildScanExtension cant be parameter nor BuildService's field
-            val buildScanExtension = project.rootProject.extensions.findByName("buildScan")
-            val buildScan = buildScanExtension?.let { BuildScanExtensionHolder(it) }
-            val buildMetricService = buildMetricServiceProvider.get()
-            val buildScanReportSettings = buildMetricService.parameters.reportingSettings.orNull?.buildScanReportSettings
+            val buildScanHolder = initBuildScanExtensionHolder(project, buildMetricServiceProvider)
+            if (buildScanHolder != null) {
+                subscribeForTaskEventsForBuildScan(project, buildMetricServiceProvider, buildScanHolder)
+            }
+
             val gradle80withBuildScanReport =
-                GradleVersion.current().baseVersion == GradleVersion.version("8.0") && buildScanReportSettings != null && buildScan != null
+                GradleVersion.current().baseVersion == GradleVersion.version("8.0") && buildScanHolder != null
 
             if (!gradle80withBuildScanReport) {
                 BuildEventsListenerRegistryHolder.getInstance(project).listenerRegistry.onTaskCompletion(buildMetricServiceProvider)
             }
+        }
 
+        private fun initBuildScanExtensionHolder(
+            project: Project,
+            buildMetricServiceProvider: Provider<BuildMetricsService>,
+        ): BuildScanExtensionHolder? {
+            val buildScanReportSettings = buildMetricServiceProvider.get().parameters.reportingSettings.orNull?.buildScanReportSettings
             if (buildScanReportSettings != null) {
-                buildScan?.also { buildScanHolder ->
-                    when {
-                        GradleVersion.current().baseVersion < GradleVersion.version("8.0") -> {
-                            buildScanHolder.buildScan.buildFinished {
-                                buildMetricServiceProvider.map {it.addBuildScanReport(buildScan)}.get()
+                // BuildScanExtension cant be parameter nor BuildService's field
+                val buildScanExtension = project.rootProject.extensions.findByName("buildScan")
+                return buildScanExtension?.let { BuildScanExtensionHolder(it) }
+            }
+            return null
+        }
+
+        private fun subscribeForTaskEventsForBuildScan(
+            project: Project,
+            buildMetricServiceProvider: Provider<BuildMetricsService>,
+            buildScanHolder: BuildScanExtensionHolder
+        ) {
+            when {
+                GradleVersion.current().baseVersion < GradleVersion.version("8.0") -> {
+                    buildScanHolder.buildScan.buildFinished {
+                        buildMetricServiceProvider.map { it.addBuildScanReport(buildScanHolder) }.get()
+                    }
+                }
+                GradleVersion.current().baseVersion < GradleVersion.version("8.1") -> {
+                    val buildMetricService = buildMetricServiceProvider.get()
+                    buildMetricService.buildReportService.initBuildScanTags(buildScanHolder, buildMetricService.parameters.label.orNull)
+                    BuildEventsListenerRegistryHolder.getInstance(project).listenerRegistry.onTaskCompletion(project.provider {
+                        OperationCompletionListener { event ->
+                            if (event is TaskFinishEvent) {
+                                val buildOperation = buildMetricService.updateBuildOperationRecord(event)
+                                val buildParameters = buildMetricService.parameters.toBuildReportParameters()
+                                val buildReportService = buildMetricServiceProvider.map { it.buildReportService }.get()
+                                buildReportService.addBuildScanReport(event, buildOperation, buildParameters, buildScanHolder)
+                                buildReportService.onFinish(event, buildOperation, buildParameters)
                             }
                         }
-                        GradleVersion.current().baseVersion < GradleVersion.version("8.1") -> {
-                            buildMetricService.buildReportService.initBuildScanTags(buildScan, buildMetricService.parameters.label.orNull)
-                            BuildEventsListenerRegistryHolder.getInstance(project).listenerRegistry.onTaskCompletion(project.provider {
-                                OperationCompletionListener { event ->
-                                    if (event is TaskFinishEvent) {
-                                        val buildOperation = buildMetricService.updateBuildOperationRecord(event)
-                                        val buildParameters = buildMetricService.parameters.toBuildReportParameters()
-                                        val buildReportService = buildMetricServiceProvider.map { it.buildReportService }.get()
-                                        buildReportService.addBuildScanReport(event, buildOperation, buildParameters, buildScanHolder)
-                                        buildReportService.onFinish(event, buildOperation, buildParameters)
-                                    }
-                                }
-
-                            })
-                        }
-                        else -> {}//do nothing, BuildScanFlowAction is used
-                    }
+
+                    })
                 }
+                else -> {}//do nothing, BuildScanFlowAction is used
             }
         }
 

libraries/tools/kotlin-gradle-plugin/src/common/kotlin/org/jetbrains/kotlin/gradle/report/BuildScanExtensionHolder.kt

@@ -8,5 +8,18 @@ package org.jetbrains.kotlin.gradle.report
 import com.gradle.scan.plugin.BuildScanExtension
 
 class BuildScanExtensionHolder(val buildScan: BuildScanExtension) : java.io.Serializable {
-    constructor(extension: Any) : this(extension as BuildScanExtension)
+
+    companion object {
+        internal operator fun invoke(extension: Any): BuildScanExtensionHolder? {
+            val buildScanExtension = try {
+                extension as BuildScanExtension
+            } catch (e: ClassNotFoundException) {
+                // Build scan plugin is applied, but BuildScanExtension class is not available due to Gradle classpath isolation
+                // Could be reproduced by applying Gradle enterprise plugin via init script: KT-59589
+                null
+            }
+
+            return buildScanExtension?.let { BuildScanExtensionHolder(it) }
+        }
+    }
 }