Bug: Add real headless browser support for UI test
Status: Resolved | Priority: Minor | Resolution: Fixed
Created: 19/May/20 06:45
Affects Version/s: 3.1.0

In the current master, there are two problems for UI test.

1. Lots of tests especially JavaScript related ones are done manually.

Appearance is better to be confirmed by our eyes but logic should be tested by test cases ideally.

 

2. Compared to the real web browsers, HtmlUnit doesn't seem to support JavaScript enough.

I added a JavaScript related test before for SPARK-31534 using HtmlUnit which is simple library based headless browser for test.

The test I added works somehow but some JavaScript related error is shown in unit-tests.log.
{code:java}
======= EXCEPTION START ========
Exception class=[net.sourceforge.htmlunit.corejs.javascript.JavaScriptException]
com.gargoylesoftware.htmlunit.ScriptException: Error: TOOLTIP: Option "sanitizeFn" provided type "window" but expected type "(null|function)". (http://192.168.1.209:60724/static/jquery-3.4.1.min.js#2)
        at com.gargoylesoftware.htmlunit.javascript.JavaScriptEngine$HtmlUnitContextAction.run(JavaScriptEngine.java:904)
        at net.sourceforge.htmlunit.corejs.javascript.Context.call(Context.java:628)
        at net.sourceforge.htmlunit.corejs.javascript.ContextFactory.call(ContextFactory.java:515)
        at com.gargoylesoftware.htmlunit.javascript.JavaScriptEngine.callFunction(JavaScriptEngine.java:835)
        at com.gargoylesoftware.htmlunit.javascript.JavaScriptEngine.callFunction(JavaScriptEngine.java:807)
        at com.gargoylesoftware.htmlunit.InteractivePage.executeJavaScriptFunctionIfPossible(InteractivePage.java:216)
        at com.gargoylesoftware.htmlunit.javascript.background.JavaScriptFunctionJob.runJavaScript(JavaScriptFunctionJob.java:52)
        at com.gargoylesoftware.htmlunit.javascript.background.JavaScriptExecutionJob.run(JavaScriptExecutionJob.java:102)
        at com.gargoylesoftware.htmlunit.javascript.background.JavaScriptJobManagerImpl.runSingleJob(JavaScriptJobManagerImpl.java:426)
        at com.gargoylesoftware.htmlunit.javascript.background.DefaultJavaScriptExecutor.run(DefaultJavaScriptExecutor.java:157)
        at java.lang.Thread.run(Thread.java:748)
Caused by: net.sourceforge.htmlunit.corejs.javascript.JavaScriptException: Error: TOOLTIP: Option "sanitizeFn" provided type "window" but expected type "(null|function)". (http://192.168.1.209:60724/static/jquery-3.4.1.min.js#2)
        at net.sourceforge.htmlunit.corejs.javascript.Interpreter.interpretLoop(Interpreter.java:1009)
        at net.sourceforge.htmlunit.corejs.javascript.Interpreter.interpret(Interpreter.java:800)
        at net.sourceforge.htmlunit.corejs.javascript.InterpretedFunction.call(InterpretedFunction.java:105)
        at net.sourceforge.htmlunit.corejs.javascript.ContextFactory.doTopCall(ContextFactory.java:413)
        at com.gargoylesoftware.htmlunit.javascript.HtmlUnitContextFactory.doTopCall(HtmlUnitContextFactory.java:252)
        at net.sourceforge.htmlunit.corejs.javascript.ScriptRuntime.doTopCall(ScriptRuntime.java:3264)
        at com.gargoylesoftware.htmlunit.javascript.JavaScriptEngine$4.doRun(JavaScriptEngine.java:828)
        at com.gargoylesoftware.htmlunit.javascript.JavaScriptEngine$HtmlUnitContextAction.run(JavaScriptEngine.java:889)
        ... 10 more
JavaScriptException value = Error: TOOLTIP: Option "sanitizeFn" provided type "window" but expected type "(null|function)".
== CALLING JAVASCRIPT ==
  function () {
      throw e;
  }
======= EXCEPTION END ========{code}
 

I tried to upgrade HtmlUnit to 2.40.0 but what is worse, the test become not working even though it works on real browsers like Chrome, Safari and Firefox without error.
{code:java}
[info] UISeleniumSuite:
[info] - SPARK-31534: text for tooltip should be escaped *** FAILED *** (17 seconds, 745 milliseconds)
[info]   The code passed to eventually never returned normally. Attempted 2 times over 12.910785232 seconds. Last failure message: com.gargoylesoftware.htmlunit.ScriptException: ReferenceError: Assignment to undefined "regeneratorRuntime" in strict mode (http://192.168.1.209:62132/static/vis-timeline-graph2d.min.js#52(Function)#1){code}
 

 To resolve those problems, it's better to support headless browser for UI test.