Upload should preserve MIMEType after first selection (#11745)

* Upload should preserve MIMEType after first selection

Fix #11698

Automated test is not run locally, need to continue with it

* Remove unused imports

* Add sleep time in testing purposes

* Getting a new instance of an input, after file is downloaded

Exclude IE from tests. Throws https://stackoverflow.com/questions/23883071/unhandled-alert-exception-modal-dialog-present-selenium , but checked manually and it works

client/src/main/java/com/vaadin/client/ui/VUpload.java

@@ -121,6 +121,8 @@ public class VUpload extends SimplePanel {
 
     private boolean immediateMode;
 
+    private String acceptMimeTypes;
+
     private Hidden maxfilesize = new Hidden();
 
     /** For internal use only. May be removed or replaced in the future. */
@@ -254,6 +256,9 @@ public class VUpload extends SimplePanel {
         fu = new VFileUpload();
         fu.setName(paintableId + "_file");
         fu.getElement().setPropertyBoolean("disabled", !enabled);
+        if (acceptMimeTypes != null && !acceptMimeTypes.isEmpty()) {
+            InputElement.as(fu.getElement()).setAccept(acceptMimeTypes);
+        }
         panel.add(fu);
         panel.add(submitButton);
         if (isImmediateMode()) {
@@ -424,5 +429,6 @@ public class VUpload extends SimplePanel {
         } else {
             InputElement.as(fu.getElement()).setAccept(acceptMimeTypes);
         }
+        this.acceptMimeTypes = acceptMimeTypes;
     }
 }

uitest/src/main/java/com/vaadin/tests/components/upload/TestUploadMIMEType.java

@@ -0,0 +1,51 @@
+package com.vaadin.tests.components.upload;
+
+import com.vaadin.annotations.Widgetset;
+import com.vaadin.server.VaadinRequest;
+import com.vaadin.tests.components.AbstractTestUI;
+import com.vaadin.ui.Upload;
+import com.vaadin.ui.Upload.Receiver;
+
+import java.io.ByteArrayOutputStream;
+import java.io.OutputStream;
+
+@Widgetset("com.vaadin.DefaultWidgetSet")
+public class TestUploadMIMEType extends AbstractTestUI {
+
+    public static final String TEST_MIME_TYPE = "application/pdf";
+    private UploadReceiver receiver = new UploadReceiver();
+
+    public static class UploadReceiver implements Receiver {
+
+        private String filename;
+
+        @Override
+        public OutputStream receiveUpload(String filename, String MIMEType) {
+            this.filename = filename;
+            return new ByteArrayOutputStream();
+        }
+
+        public String getFilename() {
+            return filename;
+        }
+
+    }
+
+    @Override
+    public String getDescription() {
+        return "MIME types for an Upload component should be preserved after the first upload";
+    }
+
+    @Override
+    protected void setup(VaadinRequest request) {
+        Upload upload = new Upload("Upload a file", receiver);
+        upload.setAcceptMimeTypes(TEST_MIME_TYPE);
+        addComponent(upload);
+    }
+
+    @Override
+    protected Integer getTicketNumber() {
+        return 119698;
+    }
+
+}

uitest/src/test/java/com/vaadin/tests/components/upload/TestUploadMIMETypeTest.java

@@ -0,0 +1,105 @@
+package com.vaadin.tests.components.upload;
+
+import com.vaadin.testbench.elements.UploadElement;
+import com.vaadin.testbench.parallel.Browser;
+import com.vaadin.tests.tb3.MultiBrowserTest;
+import org.junit.Test;
+import org.openqa.selenium.By;
+import org.openqa.selenium.WebElement;
+import org.openqa.selenium.internal.WrapsElement;
+import org.openqa.selenium.remote.DesiredCapabilities;
+import org.openqa.selenium.remote.LocalFileDetector;
+import org.openqa.selenium.remote.RemoteWebElement;
+
+import java.io.BufferedWriter;
+import java.io.File;
+import java.io.FileWriter;
+import java.io.IOException;
+import java.util.List;
+
+import static com.vaadin.tests.components.upload.TestUploadMIMEType.TEST_MIME_TYPE;
+import static org.hamcrest.CoreMatchers.is;
+import static org.junit.Assert.assertThat;
+
+public class TestUploadMIMETypeTest extends MultiBrowserTest {
+    @Override
+    public void setup() throws Exception {
+        super.setup();
+        openTestURL();
+    }
+
+    @Test
+    public void testAcceptAttribute() throws Exception {
+        WebElement input = getInput();
+        assertThat(input.getAttribute("accept"), is(TEST_MIME_TYPE));
+        uploadFile();
+        waitUntil(driver -> getSubmitButton().isEnabled());
+        //Previous element is removed, getting a new one
+        input = getInput();
+        assertThat(
+                String.format("Accept is expected to be %s , but was %s ",
+                        TEST_MIME_TYPE, input.getAttribute("accept")),
+                input.getAttribute("accept"), is(TEST_MIME_TYPE));}
+
+    private void uploadFile() throws Exception {
+        File tempFile = createTempFile();
+        fillPathToUploadInput(tempFile.getPath());
+        getSubmitButton().click();
+    }
+
+    /**
+     * @return The generated temp file handle
+     * @throws IOException
+     */
+    private File createTempFile() throws IOException {
+        File tempFile = File.createTempFile("TestFileUpload", ".pdf");
+        BufferedWriter writer = new BufferedWriter(new FileWriter(tempFile));
+        writer.write(getTempFileContents());
+        writer.close();
+        tempFile.deleteOnExit();
+        return tempFile;
+    }
+
+    private String getTempFileContents() {
+        return "This is a test file!\nRow 2\nRow3";
+    }
+
+    private void fillPathToUploadInput(String tempFileName) throws Exception {
+        // create a valid path in upload input element. Instead of selecting a
+        // file by some file browsing dialog, we use the local path directly.
+        WebElement input = getInput();
+        setLocalFileDetector(input);
+        input.sendKeys(tempFileName);
+    }
+
+    private WebElement getSubmitButton() {
+        UploadElement upload = $(UploadElement.class).first();
+        WebElement submitButton = upload.findElement(By.className("v-button"));
+        return submitButton;
+    }
+
+    private WebElement getInput() {
+        return getDriver().findElement(By.className("gwt-FileUpload"));
+    }
+
+    private void setLocalFileDetector(WebElement element) throws Exception {
+
+        if (element instanceof WrapsElement) {
+            element = ((WrapsElement) element).getWrappedElement();
+        }
+        if (element instanceof RemoteWebElement) {
+            ((RemoteWebElement) element)
+                    .setFileDetector(new LocalFileDetector());
+        } else {
+            throw new IllegalArgumentException(
+                    "Expected argument of type RemoteWebElement, received "
+                            + element.getClass().getName());
+        }
+    }
+    @Override
+    public List<DesiredCapabilities> getBrowsersToTest() {
+        // IE11 throws an `Unhandled Alert Exception`
+        //https://stackoverflow.com/questions/23883071/unhandled-alert-exception-modal-dialog-present-selenium
+        return getBrowserCapabilities(Browser.CHROME, Browser.FIREFOX);
+    }
+}