[Rev 03] RFR: 8246348: Crash in libpango on Ubuntu 20.04 with some unicode chars

[Kevin Rushforth]

On Mon, 15 Jun 2020 09:08:14 GMT, Johan Vos <jvos at openjdk.org> wrote:

>> This addresses https://bugs.openjdk.java.net/browse/JDK-8246348
>
> Johan Vos has updated the pull request incrementally with one additional commit since the last revision:
> 
>   Add test for testing Pango behavior with Character(0) and surrogate pairs

The new test look good. I confirm that it fails without your patch and passes with your patch. I added a few
suggestions to bring it in line with current best practices.

tests/system/src/test/java/test/com/sun/javafx/font/freetype/PangoTest.java line 77:

> 76:             stage.show();
> 77:             launchLatch.countDown();
> 78:         }

Our newer system tests use a `WINDOW_SHOWN` event to trigger the countdown of the latch, like this (which would be
added before the stage is shown).
            stage.addEventHandler(WindowEvent.WINDOW_SHOWN, e -> Platform.runLater(launchLatch::countDown));

This ensures that the Stage has been shown before the first test is run.

tests/system/src/test/java/test/com/sun/javafx/font/freetype/PangoTest.java line 117:

> 116:             if (!rDone.await(TIMEOUT, TimeUnit.MILLISECONDS)) {
> 117:                 throw new AssertionFailedError("Timeout waiting for runLater");
> 118:             }

This could also be replaced with `assertTrue("Timeout ...", rDone.await(TIMEOUT, TimeUnit.MILLISECONDS)` if you add
`throws Exception` to this method and the calling test methods.

modules/javafx.graphics/src/test/java/test/com/sun/javafx/text/TextLayoutTest.java line 102:

> 101:     @Ignore() // ignored since StubFontLoader used in tests return fonts with null resources
> 102:     @Test public void utf16chars() {
> 103:         GlyphLayout layout = GlyphLayout.getInstance();

Since this is `@Ignore`d with no real way to make it a useful test, maybe it would be best to revert the changes to
this file?

-------------

PR: https://git.openjdk.java.net/jfx/pull/249