feat: implement HasEnabled for Upload (#6787)

Author: sissbruecker

vaadin-upload-flow-parent/vaadin-upload-flow/src/main/java/com/vaadin/flow/component/upload/Upload.java

@@ -27,6 +27,7 @@
 import com.vaadin.flow.component.AttachEvent;
 import com.vaadin.flow.component.Component;
 import com.vaadin.flow.component.ComponentEventListener;
+import com.vaadin.flow.component.HasEnabled;
 import com.vaadin.flow.component.HasSize;
 import com.vaadin.flow.component.HasStyle;
 import com.vaadin.flow.component.Tag;
@@ -63,7 +64,7 @@
 @JsModule("@vaadin/polymer-legacy-adapter/style-modules.js")
 @NpmPackage(value = "@vaadin/upload", version = "24.6.0-alpha8")
 @JsModule("@vaadin/upload/src/vaadin-upload.js")
-public class Upload extends Component implements HasSize, HasStyle {
+public class Upload extends Component implements HasEnabled, HasSize, HasStyle {
 
     /**
      * Server-side component for the default {@code <vaadin-upload>} icon.
@@ -193,7 +194,7 @@ public Registration addAllFinishedListener(
         return addListener(AllFinishedEvent.class, listener);
     }
 
-    private StreamVariable getStreamVariable() {
+    StreamVariable getStreamVariable() {
         if (streamVariable == null) {
             streamVariable = new DefaultStreamVariable(this);
         }
@@ -425,6 +426,10 @@ public Component getDropLabelIcon() {
      * accepted on same component.
      */
     private void startUpload() {
+        if (!isEnabled()) {
+            throw new IllegalStateException(
+                    "Cannot start upload because the Upload component is disabled");
+        }
         if (getMaxFiles() != 0 && getMaxFiles() <= activeUploads) {
             throw new IllegalStateException(
                     "Maximum supported amount of uploads already started");

vaadin-upload-flow-parent/vaadin-upload-flow/src/test/java/com/vaadin/flow/component/upload/DisabledUploadTest.java

@@ -0,0 +1,34 @@
+/*
+ * Copyright 2000-2024 Vaadin Ltd.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License"); you may not
+ * use this file except in compliance with the License. You may obtain a copy of
+ * the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
+ * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
+ * License for the specific language governing permissions and limitations under
+ * the License.
+ */
+package com.vaadin.flow.component.upload;
+
+import org.junit.Assert;
+import org.junit.Test;
+
+public class DisabledUploadTest {
+    @Test
+    public void preventsStartingUploads() {
+        Upload upload = new Upload();
+        upload.setEnabled(false);
+
+        IllegalStateException exception = Assert
+                .assertThrows(IllegalStateException.class, () -> {
+                    upload.getStreamVariable().streamingStarted(null);
+                });
+        Assert.assertTrue(exception.getMessage().contains(
+                "Cannot start upload because the Upload component is disabled"));
+    }
+}

vaadin-upload-flow-parent/vaadin-upload-flow/src/test/java/com/vaadin/flow/component/upload/tests/UploadTest.java

@@ -18,6 +18,7 @@
 import org.junit.Assert;
 import org.junit.Test;
 
+import com.vaadin.flow.component.HasEnabled;
 import com.vaadin.flow.component.upload.Upload;
 import com.vaadin.flow.component.upload.receivers.MemoryBuffer;
 import com.vaadin.flow.component.upload.receivers.MultiFileMemoryBuffer;
@@ -30,6 +31,11 @@ public void uploadNewUpload() {
         Upload upload = new Upload();
     }
 
+    @Test
+    public void implementsHasEnabled() {
+        Assert.assertTrue(HasEnabled.class.isAssignableFrom(Upload.class));
+    }
+
     @Test
     public void switchBetweenSingleAndMultiFileReceiver_assertMaxFilesProperty() {
         Upload upload = new Upload();