Always show loading indicator for JavaScript RPC (#20235)

The change to not show loading indicator for JS RPC was done in
15a53d305e and looks like a refactoring
error.

Change-Id: If2a2818e0c4adc06479ecaf17764bf53fc89c095

client/src/main/java/com/vaadin/client/communication/ServerRpcQueue.java

@@ -226,10 +226,12 @@ public class ServerRpcQueue {
      */
     public boolean showLoadingIndicator() {
         for (MethodInvocation invocation : getAll()) {
-            if (isLegacyVariableChange(invocation)) {
-                // Always show loading indicator for legacy requests
+            if (isLegacyVariableChange(invocation)
+                    || isJavascriptRpc(invocation)) {
+                // Always show loading indicator for legacy and JS requests as
+                // they have no @NoLoadingIndicator they can use
                 return true;
-            } else if (!isJavascriptRpc(invocation)) {
+            } else {
                 Type type = new Type(invocation.getInterfaceName(), null);
                 Method method = type.getMethod(invocation.getMethodName());
                 if (!TypeDataStore.isNoLoadingIndicator(method)) {

uitest/src/main/java/com/vaadin/tests/components/javascriptcomponent/JSComponentLoadingIndicator.java

@@ -0,0 +1,38 @@
+package com.vaadin.tests.components.javascriptcomponent;
+
+import com.vaadin.annotations.JavaScript;
+import com.vaadin.server.VaadinRequest;
+import com.vaadin.tests.components.AbstractTestUI;
+import com.vaadin.ui.AbstractJavaScriptComponent;
+import com.vaadin.ui.JavaScriptFunction;
+import com.vaadin.ui.Label;
+
+import elemental.json.JsonArray;
+
+public class JSComponentLoadingIndicator extends AbstractTestUI {
+
+    @JavaScript({ "JSComponent.js" })
+    public class JSComponent extends AbstractJavaScriptComponent {
+        public JSComponent() {
+            addFunction("test", new JavaScriptFunction() {
+                @Override
+                public void call(JsonArray arguments) {
+                    try {
+                        Thread.sleep(1000);
+                        Label label = new Label("pong");
+                        label.addStyleName("pong");
+                        addComponent(label);
+                    } catch (InterruptedException e) {
+                        e.printStackTrace();
+                    }
+                }
+            });
+        }
+    }
+
+    @Override
+    protected void setup(VaadinRequest request) {
+        addComponent(new JSComponent());
+    }
+
+}

uitest/src/main/resources/com/vaadin/tests/components/javascriptcomponent/JSComponent.js

@@ -0,0 +1,11 @@
+com_vaadin_tests_components_javascriptcomponent_JSComponentLoadingIndicator_JSComponent = function()
+{
+	var connector = this;
+	var e = this.getElement();
+
+	e.innerText="click me to ping server";
+	e.id="js";
+	e.addEventListener("click", function() {
+		connector.test();
+	});
+}

uitest/src/test/java/com/vaadin/tests/components/javascriptcomponent/JSComponentLoadingIndicatorTest.java

@@ -0,0 +1,29 @@
+package com.vaadin.tests.components.javascriptcomponent;
+
+import org.junit.Assert;
+import org.junit.Test;
+import org.openqa.selenium.WebElement;
+
+import com.vaadin.testbench.By;
+import com.vaadin.tests.tb3.SingleBrowserTest;
+
+public class JSComponentLoadingIndicatorTest extends SingleBrowserTest {
+
+    @Test
+    public void ensureLoadingIndicatorShown() {
+        openTestURL();
+        testBench().disableWaitForVaadin();
+
+        WebElement js = findElement(By.id("js"));
+        js.click();
+        waitUntilLoadingIndicatorVisible();
+        waitUntilLoadingIndicatorNotVisible();
+        Assert.assertEquals(1, findElements(By.className("pong")).size());
+
+        js.click();
+        waitUntilLoadingIndicatorVisible();
+        waitUntilLoadingIndicatorNotVisible();
+        Assert.assertEquals(2, findElements(By.className("pong")).size());
+    }
+
+}

uitest/src/test/java/com/vaadin/tests/tb3/AbstractTB3Test.java

@@ -1015,15 +1015,20 @@ public abstract class AbstractTB3Test extends ParallelTest {
         return loadingIndicator.isDisplayed();
     }
 
-    protected void waitUntilLoadingIndicatorNotVisible() {
+    protected void waitUntilLoadingIndicatorVisible() {
         waitUntil(new ExpectedCondition<Boolean>() {
-
             @Override
             public Boolean apply(WebDriver input) {
-                WebElement loadingIndicator = input.findElement(By
-                        .className("v-loading-indicator"));
+                return isLoadingIndicatorVisible();
+            }
+        });
+    }
 
-                return !loadingIndicator.isDisplayed();
+    protected void waitUntilLoadingIndicatorNotVisible() {
+        waitUntil(new ExpectedCondition<Boolean>() {
+            @Override
+            public Boolean apply(WebDriver input) {
+                return !isLoadingIndicatorVisible();
             }
         });
     }