fix: Gradle frontend folder handling

flow-plugins/flow-gradle-plugin/src/main/kotlin/com/vaadin/gradle/PrepareFrontendOutputProperties.kt

@@ -15,6 +15,7 @@
  */
 package com.vaadin.gradle
 
+import com.vaadin.flow.plugin.base.BuildFrontendUtil
 import com.vaadin.flow.server.Constants
 import com.vaadin.flow.server.frontend.FrontendUtils
 import org.gradle.api.Project
@@ -70,8 +71,8 @@ internal class PrepareFrontendOutputProperties(
     }
 
     @OutputDirectory
-    public fun getGeneratedTsFolder(): Property<File> =
-        config.generatedTsFolder
+    public fun getGeneratedTsFolder(): File =
+            BuildFrontendUtil.getGeneratedFrontendDirectory(GradlePluginAdapter(project, config, true))
 
     @OutputDirectory
     public fun getResourceOutputDirectory(): Property<File> = config.resourceOutputDirectory

flow-plugins/flow-gradle-plugin/src/main/kotlin/com/vaadin/gradle/VaadinBuildFrontendTask.kt

@@ -73,7 +73,7 @@ public open class VaadinBuildFrontendTask : DefaultTask() {
         check(tokenFile.exists()) { "token file $tokenFile doesn't exist!" }
 
         val cleanTask = TaskCleanFrontendFiles(config.npmFolder.get(),
-            config.frontendDirectory.get(), adapter.classFinder
+                BuildFrontendUtil.getGeneratedFrontendDirectory(adapter), adapter.classFinder
         )
         BuildFrontendUtil.runNodeUpdater(adapter)
 
@@ -105,7 +105,7 @@ public open class VaadinBuildFrontendTask : DefaultTask() {
      */
     protected open fun cleanFrontendFiles(): Boolean {
         val adapter = GradlePluginAdapter(project, config, false)
-        if (FrontendUtils.isHillaUsed(adapter.frontendDirectory(),
+        if (FrontendUtils.isHillaUsed(BuildFrontendUtil.getGeneratedFrontendDirectory(adapter),
                         adapter.classFinder)) {
             /*
              * Override this to not clean generated frontend files after the

flow-plugins/flow-gradle-plugin/src/main/kotlin/com/vaadin/gradle/VaadinFlowPluginExtension.kt

@@ -15,6 +15,7 @@
  */
 package com.vaadin.gradle
 
+import com.vaadin.flow.plugin.base.BuildFrontendUtil
 import com.vaadin.flow.server.Constants
 import com.vaadin.flow.server.InitParameters
 import com.vaadin.flow.server.frontend.FrontendTools
@@ -421,7 +422,7 @@ public class PluginEffectiveConfiguration(
         .convention(false)
 
     public val reactEnable: Provider<Boolean> = extension.reactEnable
-        .convention(FrontendUtils.isReactRouterRequired(frontendDirectory.get()))
+        .convention(FrontendUtils.isReactRouterRequired(BuildFrontendUtil.getGeneratedFrontendDirectory(GradlePluginAdapter(project, this, true))))
         .overrideWithSystemProperty(InitParameters.REACT_ENABLE)
 
     public val cleanFrontendFiles: Property<Boolean> = extension.cleanFrontendFiles

flow-plugins/flow-gradle-plugin/src/main/kotlin/com/vaadin/gradle/VaadinPrepareFrontendTask.kt

@@ -22,6 +22,7 @@ import org.gradle.api.Task
 import org.gradle.api.tasks.CacheableTask
 import org.gradle.api.tasks.Nested
 import org.gradle.api.tasks.TaskAction
+import kotlin.math.log
 
 /**
  * This task checks that node and npm tools are installed, copies frontend
@@ -58,9 +59,9 @@ public open class VaadinPrepareFrontendTask : DefaultTask() {
     @TaskAction
     public fun vaadinPrepareFrontend() {
         // Remove Frontend/generated folder to get clean files copied/generated
-        project.delete(config.generatedTsFolder)
-        logger.info("Running the vaadinPrepareFrontend task with effective configuration $config")
         val adapter = GradlePluginAdapter(project, config, true)
+        project.delete(BuildFrontendUtil.getGeneratedFrontendDirectory(adapter))
+        logger.debug("Running the vaadinPrepareFrontend task with effective configuration $config")
         val tokenFile = BuildFrontendUtil.propagateBuildInfo(adapter)
 
         logger.info("Generated token file $tokenFile")

flow-plugins/flow-plugin-base/src/main/java/com/vaadin/flow/plugin/base/BuildFrontendUtil.java

@@ -420,7 +420,7 @@ public static void runDevBuildNodeUpdater(PluginAdapterBuild adapter)
      *            PluginAdapterBase
      * @return correct folder or legacy folder if not user defined
      */
-    private static File getFrontendDirectory(PluginAdapterBase adapter) {
+    public static File getFrontendDirectory(PluginAdapterBase adapter) {
         File frontendDir = adapter.frontendDirectory();
         if (!frontendDir.exists() && frontendDir.toPath()
                 .endsWith(DEFAULT_FRONTEND_DIR.substring(2))) {
@@ -440,7 +440,7 @@ private static File getFrontendDirectory(PluginAdapterBase adapter) {
      *            PluginAdapterBase
      * @return correct generated folder as child to frontend
      */
-    private static File getGeneratedFrontendDirectory(
+    public static File getGeneratedFrontendDirectory(
             PluginAdapterBase adapter) {
         if (adapter.generatedTsFolder().toPath()
                 .startsWith(adapter.frontendDirectory().toPath())) {

vaadin-dev-server/src/main/java/com/vaadin/base/devserver/startup/DevModeInitializer.java

@@ -273,11 +273,9 @@ public static DevModeHandler initDevModeHandler(Set<Class<?>> classes,
                         InitParameters.ADDITIONAL_POSTINSTALL_PACKAGES, "")
                 .split(",");
 
-        String frontendGeneratedFolderName = config
-                .getStringProperty(PROJECT_FRONTEND_GENERATED_DIR_TOKEN,
-                        Paths.get(baseDir.getAbsolutePath(),
-                                DEFAULT_PROJECT_FRONTEND_GENERATED_DIR)
-                                .toString());
+        String frontendGeneratedFolderName = config.getStringProperty(
+                PROJECT_FRONTEND_GENERATED_DIR_TOKEN,
+                Paths.get(frontendFolder, GENERATED).toString());
         File frontendGeneratedFolder = new File(frontendGeneratedFolderName);
         File jarFrontendResourcesFolder = new File(frontendGeneratedFolder,
                 FrontendUtils.JAR_RESOURCES_FOLDER);