From 21afecd03e705b3ee625da4ee6e4b043fd10b2de Mon Sep 17 00:00:00 2001
From: Artur <artur@vaadin.com>
Date: Fri, 2 Jun 2023 08:55:20 +0300
Subject: [PATCH] fix: Scan method annotations (#16937)

Fixes #16925
---
 .../scanner/FrontendClassVisitor.java         |  7 ++
 .../scanner/ScannerDependenciesTest.java      | 73 +++++++++++++++++++
 2 files changed, 80 insertions(+)

diff --git a/flow-server/src/main/java/com/vaadin/flow/server/frontend/scanner/FrontendClassVisitor.java b/flow-server/src/main/java/com/vaadin/flow/server/frontend/scanner/FrontendClassVisitor.java
index 90ad9110109..fad79417a9a 100644
--- a/flow-server/src/main/java/com/vaadin/flow/server/frontend/scanner/FrontendClassVisitor.java
+++ b/flow-server/src/main/java/com/vaadin/flow/server/frontend/scanner/FrontendClassVisitor.java
@@ -65,6 +65,13 @@ public FrontendMethodVisitor() {
             super(Opcodes.ASM9);
         }
 
+        @Override
+        public AnnotationVisitor visitAnnotation(String descriptor,
+                boolean visible) {
+            addSignatureToClasses(classInfo.children, descriptor);
+            return annotationVisitor;
+        }
+
         // We are interested in the new instances created inside the method
         @Override
         public void visitTypeInsn(int opcode, String type) {
diff --git a/flow-server/src/test/java/com/vaadin/flow/server/frontend/scanner/ScannerDependenciesTest.java b/flow-server/src/test/java/com/vaadin/flow/server/frontend/scanner/ScannerDependenciesTest.java
index 88599ffbb97..ec2f8fe0afe 100644
--- a/flow-server/src/test/java/com/vaadin/flow/server/frontend/scanner/ScannerDependenciesTest.java
+++ b/flow-server/src/test/java/com/vaadin/flow/server/frontend/scanner/ScannerDependenciesTest.java
@@ -1,16 +1,25 @@
 package com.vaadin.flow.server.frontend.scanner;
 
+import java.io.InputStream;
+import java.lang.reflect.AnnotatedElement;
+import java.net.URL;
 import java.util.ArrayList;
 import java.util.Arrays;
 import java.util.HashSet;
 import java.util.List;
 import java.util.Set;
+import java.util.function.Supplier;
 
 import org.junit.Test;
+import org.objectweb.asm.ClassReader;
 
+import com.vaadin.flow.component.Component;
 import com.vaadin.flow.component.dependency.JsModule;
 import com.vaadin.flow.router.Route;
 import com.vaadin.flow.server.frontend.scanner.ClassFinder.DefaultClassFinder;
+import com.vaadin.flow.server.frontend.scanner.ScannerDependenciesTest.UISearchField.SearchFieldComponentDefinitionCreator;
+import com.vaadin.flow.server.frontend.scanner.ScannerDependenciesTest.UISearchField.UISearchLayout;
+import com.vaadin.flow.server.frontend.scanner.ScannerDependenciesTest.UISearchField.UISearchLayout.SearchLayoutComponentDefinitionCreator;
 import com.vaadin.flow.server.frontend.scanner.ScannerTestComponents.BridgeClass;
 import com.vaadin.flow.server.frontend.scanner.ScannerTestComponents.Component0;
 import com.vaadin.flow.server.frontend.scanner.ScannerTestComponents.Component1;
@@ -242,4 +251,68 @@ public void should_visitServices() {
         DepsTests.assertImportsExcludingUI(deps.getModules(),
                 "dynamic-component.js", "dynamic-layout.js");
     }
+
+    @Test
+    public void should_visitMethodAnnotations() {
+        FrontendDependencies deps = getFrontendDependencies(
+                MethodAnnotationRoute.class);
+        DepsTests.assertImportsExcludingUI(deps.getModules(),
+                "./search-layout.js", "./search-field.js");
+    }
+
+    @Route
+    public static class MethodAnnotationRoute {
+        private MyPmo myPmo;
+    }
+
+    @UISearchLayout
+    public static class MyPmo {
+
+        @UISearchField()
+        public String getText() {
+            return "value to be displayed";
+        }
+    }
+
+    public interface ComponentDefinitionCreator<T> {
+
+    }
+
+    public @interface LinkTo {
+        Class<?> value();
+    }
+
+    @LinkTo(SearchFieldComponentDefinitionCreator.class)
+    public @interface UISearchField {
+        class SearchFieldComponentDefinitionCreator
+                implements ComponentDefinitionCreator<UISearchField> {
+            public Supplier<Component> create(UISearchField annotation,
+                    AnnotatedElement annotatedElement) {
+                return () -> new SearchField();
+            }
+        }
+
+        @LinkTo(SearchLayoutComponentDefinitionCreator.class)
+        public @interface UISearchLayout {
+            class SearchLayoutComponentDefinitionCreator
+                    implements ComponentDefinitionCreator<UISearchLayout> {
+                public Supplier<Component> create(UISearchLayout annotation,
+                        AnnotatedElement annotatedElement) {
+                    return () -> new SearchLayout();
+                }
+            }
+        }
+
+        @JsModule("./search-layout.js")
+        public static class SearchLayout extends Component {
+
+        }
+
+        @JsModule("./search-field.js")
+        public static class SearchField extends Component {
+
+        }
+
+    }
+
 }