Avoid populating font family aliases if family matched

When trying to match a font request to fonts in the database we might
end up with a mismatch due to the style not being available, but the
font family itself was.

If that's the case there's no point in trying to populate font aliases,
so we explicitly propagate this fact back to QFontDatabasePrivate::findFont
so that it can choose to not populate family aliases.

Fixes: QTBUG-98369
Fixes: QTBUG-99216
Change-Id: I14470554c73eace836f57cb65e63ada594ccf62e
Reviewed-by: Timur Pocheptsov <timur.pocheptsov@qt.io>
Reviewed-by: Eskil Abrahamsen Blomfeldt <eskil.abrahamsen-blomfeldt@qt.io>
(cherry picked from commit 69d525a6fa19934b3e57f503132bb4ab19f6b923)
Reviewed-by: Qt Cherry-pick Bot <cherrypick_bot@qt-project.org>

1 files changed, 15 insertions, 9 deletions

diff --git a/src/gui/text/qfontdatabase.cpp b/src/gui/text/qfontdatabase.cpp
index 1486c035e8..f7705b16a9 100644
--- a/src/gui/text/qfontdatabase.cpp
+++ b/src/gui/text/qfontdatabase.cpp
@@ -905,6 +905,13 @@ static QtFontStyle *bestStyle(QtFontFoundry *foundry, const QtFontStyle::Key &st
     return foundry->styles[best];
 }
 
+enum {
+    FamilyMismatch      = 0x800000,
+    ScriptMismatch      = 0x080000,
+    PitchMismatch       = 0x004000,
+    StyleMismatch       = 0x002000,
+    BitmapScaledPenalty = 0x001000
+};
 
 static
 unsigned int bestFoundry(int script, unsigned int score, int styleStrategy,
@@ -1008,20 +1015,16 @@ unsigned int bestFoundry(int script, unsigned int score, int styleStrategy,
 
 
         unsigned int this_score = 0x0000;
-        enum {
-            PitchMismatch       = 0x4000,
-            StyleMismatch       = 0x2000,
-            BitmapScaledPenalty = 0x1000
-        };
+
         if (pitch != '*') {
             if ((pitch == 'm' && !family->fixedPitch)
                 || (pitch == 'p' && family->fixedPitch))
-                this_score += PitchMismatch;
+                this_score |= PitchMismatch;
         }
         if (styleKey != style->key)
-            this_score += StyleMismatch;
+            this_score |= StyleMismatch;
         if (!style->smoothScalable && px != size->pixelSize) // bitmap scaled
-            this_score += BitmapScaledPenalty;
+            this_score |= BitmapScaledPenalty;
         if (px != pixelSize) // close, but not exact, size match
             this_score += qAbs(px - pixelSize);
 
@@ -1106,11 +1109,14 @@ static int match(int script,
 
         if (!matchFamilyName(family_name, test.family))
             continue;
+        score &= ~FamilyMismatch;
+
         test.family->ensurePopulated();
 
         // Check if family is supported in the script we want
         if (writingSystem != QFontDatabase::Any && !familySupportsWritingSystem(test.family, writingSystem))
             continue;
+        score &= ~ScriptMismatch;
 
         // as we know the script is supported, we can be sure
         // to find a matching font here.
@@ -2410,7 +2416,7 @@ QFontEngine *QFontDatabasePrivate::findFont(const QFontDef &req,
     QList<int> blackListed;
     unsigned int score = UINT_MAX;
     int index = match(multi ? QChar::Script_Common : script, request, family_name, foundry_name, &desc, blackListed, &score);
-    if (score > 0 && QGuiApplicationPrivate::platformIntegration()->fontDatabase()->populateFamilyAliases(family_name)) {
+    if ((score & FamilyMismatch) && QGuiApplicationPrivate::platformIntegration()->fontDatabase()->populateFamilyAliases(family_name)) {
         // We populated family aliases (e.g. localized families), so try again
         index = match(multi ? QChar::Script_Common : script, request, family_name, foundry_name, &desc, blackListed);
     }