On Wed, 4 Mar 2020 14:02:51 GMT, Erik Helin <ehe...@openjdk.org> wrote:
>> While testing JavaFX using gradle 6.3-nightly and JDK 14, I ran into what
>> turned out to be a latent test bug in the AppJSCallback* apps that are
>> launched by ModuleLauncherTest. The launched apps construct a WebView
>> instance, obtain a WebEngine instance from the WebView, add a state listener
>> to the WebEngine, load the web content, and then return from the
>> Application::start method. The WebView instance is held a local variable,
>> and so is subject to garbage collection once it goes out of scope when the
>> start method returns.
>>
>> In addition, the test apps did not check for successful launching of the
>> application or successful loading of the web content, which led to the test
>> suite hanging (else it would have been a simple test failure).
>>
>> Note that I don't know (nor care) what changed in JDK 14 to make this more
>> likely to occur, but since the test itself is demonstrably wrong, it needs
>> to be fixed.
>>
>> The main part of the fix was to make the WebEngine an instance variable. In
>> order to make the test more robust, I also modified it to launch the
>> application in another thread, and having the main thread check that the
>> application launched successfully and that the web content was loaded
>> successfully, after which I did the assertion check for the correct number
>> of callbacks.
>>
>> The 5 different apps only differ from each other in the name of the class,
>> the name of the package from which MyCallback is imported, and possibly the
>> expected number of callbacks. I diffed AppJSCallbackExported.java against
>> the other 4 test files and the diffs are essentially the same as they were
>> before this change. Reviewers thus only need to review one of the tests in
>> detail.
>>
>> For example, here are the diffs between AppJSCallbackExported and
>> AppJSCallbackUnexported:
>>
>> $ diff .../AppJSCallbackExported.java .../AppJSCallbackUnexported.java
>>
>> 37c37
>> < import myapp5.pkg2.MyCallback;
>> ---
>>> import myapp5.pkg1.MyCallback;
>> 45c45
>> < public class AppJSCallbackExported extends Application {
>> ---
>>> public class AppJSCallbackUnexported extends Application {
>> 77c77
>> < Util.assertEquals(1, callbackCount);
>> ---
>>> Util.assertEquals(0, callbackCount);
>
> Please ignore this comment, this is for debugging Skara that might have some
> mailing list mirroring issues 😄
Please ignore this comment as well, it is also for debugging issues with Skara
and mailman :email: ðŸ˜
-------------
PR: https://git.openjdk.java.net/jfx/pull/134
