Scroll event not triggering correctly?
I've ran into a case where triggering javascript scrollintoView has no effect, not triggering an event that is supposed to dynamically load the next page of data.
Here is a basic test case:
import org.junit.jupiter.api.AfterAll;
import org.junit.jupiter.api.Assertions;
import org.junit.jupiter.api.Test;
import org.openqa.selenium.By;
import org.openqa.selenium.JavascriptExecutor;
import org.openqa.selenium.WebDriver;
import org.openqa.selenium.chrome.ChromeDriver;
import org.openqa.selenium.htmlunit.HtmlUnitDriver;
import java.io.IOException;
import java.net.URISyntaxException;
import java.nio.file.Files;
import java.nio.file.Path;
public class ScrollTest {
public static final String PAGE;
static {
try {
PAGE = Files.readString(Path.of(ScrollTest.class.getClassLoader().getResource("testPage1.html").toURI()));
} catch (IOException | URISyntaxException e) {
throw new RuntimeException(e);
}
}
private static final HtmlUnitDriver huDriver = new HtmlUnitDriver(true);
private static final WebDriver chromeDriver = new ChromeDriver();
@AfterAll
static void closeAll(){
huDriver.close();
chromeDriver.close();
}
@Test
void givenPageWithTable_whenScrollTo_TriggerEvent(){
runTest(chromeDriver);
runTest(huDriver);
}
private static void runTest(WebDriver driver) {
driver.get(PAGE);
((JavascriptExecutor) driver).executeScript("arguments[0].scrollIntoView()", driver.findElement(By.id("last")));
Assertions.assertEquals(1L,
((JavascriptExecutor) driver).executeScript("return count"));
}
}and here is the html file I used for testing, feel free to add more table rows if needed
data:text/html,
<table>
<tr>row</tr>
<br>
<tr id="last"></tr>
</table>
<script>
var count = 0;
const observer = new IntersectionObserver((entries) => {
entries.forEach((entry) => {
console.log("triggered");
count++;
})
});
observer.observe(document.getElementById("last"));
</script>The results are incosistent:
org.opentest4j.AssertionFailedError:
Expected :1
Actual :0
<Click to see difference>
at ScrollTest.runTest(ScrollTest.java:45)
at ScrollTest.givenPageWithTable_whenScrollTo_TriggerEvent(ScrollTest.java:39)
...removed rest of generic stack trace...
HtmlUnit / htmlunit
HtmlUnit is a "GUI-Less browser for Java programs".
871
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