fix: No react module for Vaadin Router (#19878)

* fix: No react module for Vaadin Router

Remove reactOutlet module
if we are not running react,
but are using Vaadin Router
inferred from index.ts

Fixes #19870

* Simplify

Author: caalador

flow-server/src/main/java/com/vaadin/flow/server/frontend/scanner/FrontendDependenciesScanner.java

@@ -100,7 +100,8 @@ public FrontendDependenciesScanner createScanner(
             if (allDependenciesScan) {
                 // this dep scanner can't distinguish embeddable web component
                 // frontend related annotations
-                return new FullDependenciesScanner(finder, featureFlags);
+                return new FullDependenciesScanner(finder, featureFlags,
+                        reactEnabled);
             } else {
                 return new FrontendDependencies(finder,
                         generateEmbeddableWebComponents, featureFlags,

flow-server/src/main/java/com/vaadin/flow/server/frontend/scanner/FullDependenciesScanner.java

@@ -91,7 +91,24 @@ class FullDependenciesScanner extends AbstractDependenciesScanner {
      *            available feature flags and their status
      */
     FullDependenciesScanner(ClassFinder finder, FeatureFlags featureFlags) {
-        this(finder, AnnotationReader::getAnnotationsFor, featureFlags);
+        this(finder, AnnotationReader::getAnnotationsFor, featureFlags, true);
+    }
+
+    /**
+     * Creates a new scanner instance which discovers all dependencies in the
+     * classpath.
+     *
+     * @param finder
+     *            a class finder
+     * @param featureFlags
+     *            available feature flags and their status
+     * @param reactEnabled
+     *            true if react classes are enabled
+     */
+    FullDependenciesScanner(ClassFinder finder, FeatureFlags featureFlags,
+            boolean reactEnabled) {
+        this(finder, AnnotationReader::getAnnotationsFor, featureFlags,
+                reactEnabled);
     }
 
     /**
@@ -104,10 +121,12 @@ class FullDependenciesScanner extends AbstractDependenciesScanner {
      *            a strategy to discover class annotations
      * @param featureFlags
      *            available feature flags and their status
+     * @param reactEnabled
+     *            true if react classes are enabled
      */
     FullDependenciesScanner(ClassFinder finder,
             SerializableBiFunction<Class<?>, Class<? extends Annotation>, List<? extends Annotation>> annotationFinder,
-            FeatureFlags featureFlags) {
+            FeatureFlags featureFlags, boolean reactEnabled) {
         super(finder, featureFlags);
 
         long start = System.currentTimeMillis();
@@ -144,6 +163,11 @@ class FullDependenciesScanner extends AbstractDependenciesScanner {
         collectScripts(scriptsSet, scriptsSetDevelopment, JavaScript.class);
         cssData = discoverCss();
 
+        if (!reactEnabled) {
+            modulesSet.removeIf(
+                    module -> module.contains("ReactRouterOutletElement.tsx"));
+        }
+
         modules = new ArrayList<>(modulesSet);
         modulesDevelopment = new ArrayList<>(modulesSetDevelopment);
         scripts = new ArrayList<>(scriptsSet);

flow-server/src/test/java/com/vaadin/flow/server/frontend/scanner/FullDependenciesScannerTest.java

@@ -336,7 +336,7 @@ public void getModules_explcitTheme_returnAllModulesExcludingNotUsedTheme_getCla
                     }
                     Assert.fail();
                     return null;
-                }, null);
+                }, null, true);
 
         DepsTests.assertImportCount(28, scanner.getModules());
         List<String> modules = DepsTests.merge(scanner.getModules());
@@ -405,7 +405,7 @@ private FullDependenciesScanner setUpAnnotationScanner(
 
         return new FullDependenciesScanner(finder,
                 (type, annotation) -> findAnnotations(type, annotationType),
-                null);
+                null, true);
     }
 
     private FullDependenciesScanner setUpThemeScanner(
@@ -425,7 +425,8 @@ private FullDependenciesScanner setUpThemeScanner(
         Mockito.when(finder.getAnnotatedClasses(fakeNoThemeClass))
                 .thenReturn(noThemeClasses);
 
-        return new FullDependenciesScanner(finder, annotationFinder, null) {
+        return new FullDependenciesScanner(finder, annotationFinder, null,
+                true) {
             @Override
             protected Class<? extends AbstractTheme> getLumoTheme() {
                 return FakeLumoTheme.class;

flow-server/src/test/java/com/vaadin/flow/server/frontend/scanner/FullScannerPwaTest.java

@@ -27,7 +27,8 @@ protected PwaConfiguration getPwaConfiguration(Class<?>... classes)
                 .getAnnotatedClasses(clazz);
 
         FullDependenciesScanner fullDependenciesScanner = new FullDependenciesScanner(
-                finder, (type, annotation) -> findPwaAnnotations(type), null);
+                finder, (type, annotation) -> findPwaAnnotations(type), null,
+                true);
         return fullDependenciesScanner.getPwaConfiguration();
     }