Make HarfBuzz-NG the default shaper on Mac

For AAT shaping support, we need either the pre-QPA shaping trick
or the new HarfBuzz on Mac; prefer the latter.
Disable some test cases aimed to test the HB-old behavior; enable ones
that should guarantee shaping-unaware behavior.

[ChangeLog][OS X] Use CoreText text shaping engine for support of
complex scripts. If required, the shaping engine used in previous
versions can be preferred by configuring Qt with -no-harfbuzz.
Alternatively, the QT_HARFBUZZ environment variable could be set to "old".

Task-number: QTBUG-18980 (relates)
Task-number: QTBUG-38246
Change-Id: Iee6fe4f5bc047e77259182b8585385c5febd02b3
Reviewed-by: Eskil Abrahamsen Blomfeldt <eskil.abrahamsen-blomfeldt@digia.com>

1 files changed, 16 insertions, 0 deletions

diff --git a/tests/auto/gui/text/qtextscriptengine/tst_qtextscriptengine.cpp b/tests/auto/gui/text/qtextscriptengine/tst_qtextscriptengine.cpp
index c4db669695..5dfb025510 100644
--- a/tests/auto/gui/text/qtextscriptengine/tst_qtextscriptengine.cpp
+++ b/tests/auto/gui/text/qtextscriptengine/tst_qtextscriptengine.cpp
@@ -1105,6 +1105,9 @@ void tst_QTextScriptEngine::mirroredChars()
 
 void tst_QTextScriptEngine::controlInSyllable_qtbug14204()
 {
+#ifdef Q_OS_MAC
+    QSKIP("Result differs for HarfBuzz-NG, skip test.");
+#endif
     QFontDatabase db;
     if (!db.families().contains(QStringLiteral("Aparajita")))
         QSKIP("couldn't find 'Aparajita' font");
@@ -1143,6 +1146,10 @@ void tst_QTextScriptEngine::combiningMarks_qtbug15675_data()
     QTest::addColumn<QFont>("font");
     QTest::addColumn<QString>("string");
 
+#ifdef Q_OS_MAC
+    QSKIP("Result differs for HarfBuzz-NG, skip test.");
+#endif
+
     bool hasTests = false;
 
     QStringList families;
@@ -1274,13 +1281,22 @@ void tst_QTextScriptEngine::thaiWithZWJ()
         QCOMPARE(logClusters[i], ushort(i));
     for (int i = 0; i < 10; i++)
         QCOMPARE(logClusters[i+7], ushort(0));
+#ifndef Q_OS_MAC
+    // ### Result differs for HarfBuzz-NG
     QCOMPARE(logClusters[17], ushort(1));
+#endif
 
     // A thai implementation could either remove the ZWJ and ZWNJ characters, or hide them.
     // The current implementation hides them, so we test for that.
     // The only characters that we should be hiding are the ZWJ and ZWNJ characters in position 1 and 3.
     const QGlyphLayout glyphLayout = e->layoutData->glyphLayout;
     for (int i = 0; i < 18; i++) {
+#ifdef Q_OS_MAC
+        // ### Result differs for HarfBuzz-NG
+        if (i == 17)
+            QCOMPARE(glyphLayout.advances[i].toInt(), 0);
+        else
+#endif
         if (i == 1 || i == 3)
             QCOMPARE(glyphLayout.advances[i].toInt(), 0);
         else