wait for running async ops before quit the webclient

Author: rbri

pom.xml

@@ -5,7 +5,7 @@
 
     <groupId>org.seleniumhq.selenium</groupId>
     <artifactId>htmlunit3-driver</artifactId>
-    <version>4.23.0</version>
+    <version>4.24.0-SNAPSHOT</version>
 
     <name>${project.artifactId}</name>
     <description>WebDriver compatible driver for HtmlUnit headless browser</description>

src/main/java/org/openqa/selenium/htmlunit/HtmlUnitDriver.java

@@ -788,12 +788,31 @@ public void close() {
 
     @Override
     public void quit() {
-        if (webClient_ != null) {
-            alert_.close();
-            webClient_.close();
-            webClient_ = null;
+        // closing the web client while some async processes are running
+        // will produce strange effects; therefore wait until they are done
+        while (runAsyncRunning_) {
+            try {
+                Thread.sleep(10);
+            }
+            catch (final InterruptedException e) {
+                throw new RuntimeException(e);
+            }
+        }
+
+        conditionLock_.lock();
+        runAsyncRunning_ = true;
+        try {
+            if (webClient_ != null) {
+                alert_.close();
+                webClient_.close();
+                webClient_ = null;
+            }
+            defaultExecutor_.shutdown();
+        }
+        finally {
+            runAsyncRunning_ = false;
+            conditionLock_.unlock();
         }
-        defaultExecutor_.shutdown();
     }
 
     @Override

src/test/java/org/openqa/selenium/htmlunit/WebDriverTestCase.java

@@ -543,15 +543,15 @@ protected WebDriver buildWebDriver() throws IOException {
         }
         if (webDriver_ == null) {
             final HtmlUnitDriverOptions driverOptions = new HtmlUnitDriverOptions(getBrowserVersion());
-            
+
             if (isWebClientCached()) {
                 driverOptions.setCapability(HtmlUnitOption.optHistorySizeLimit, 0);
             }
-            
+
             if (getWebClientTimeout() != null) {
                 driverOptions.setCapability(HtmlUnitOption.optTimeout, getWebClientTimeout());
             }
-            
+
             webDriver_ = new HtmlUnitDriver(driverOptions);
             webDriver_.setExecutor(EXECUTOR_POOL);
         }