Fix Text baselineOffset caclulations.

Update the baselineOffset when short cutting layout due to an empty
text property.  And allow alterations to the baseline due to images,
font scaling and custom layouts when doing a layout.

Task-number: QTBUG-24303
Change-Id: I5a31a6108cded490fef8b0674e15558ea4e22d6b
Reviewed-by: Michael Brasser <michael.brasser@nokia.com>

1 files changed, 249 insertions, 1 deletions

diff --git a/tests/auto/quick/qquicktext/tst_qquicktext.cpp b/tests/auto/quick/qquicktext/tst_qquicktext.cpp
index 316395b4b2..86de5014e0 100644
--- a/tests/auto/quick/qquicktext/tst_qquicktext.cpp
+++ b/tests/auto/quick/qquicktext/tst_qquicktext.cpp
@@ -131,6 +131,9 @@ private slots:
     void fontFormatSizes_data();
     void fontFormatSizes();
 
+    void baselineOffset_data();
+    void baselineOffset();
+
 private:
     QStringList standard;
     QStringList richText;
@@ -1692,7 +1695,7 @@ void tst_qquicktext::boundingRect()
     QCOMPARE(text->boundingRect().x(), qreal(0));
     QCOMPARE(text->boundingRect().y(), qreal(0));
     QCOMPARE(text->boundingRect().width(), qreal(0));
-    QCOMPARE(text->boundingRect().height(), QFontMetricsF(text->font()).height());
+    QCOMPARE(text->boundingRect().height(), qreal(qCeil(QFontMetricsF(text->font()).height())));
 
     text->setText("Hello World");
 
@@ -2592,6 +2595,251 @@ void tst_qquicktext::fontFormatSizes()
     delete view;
 }
 
+typedef qreal (*ExpectedBaseline)(QQuickText *item);
+Q_DECLARE_METATYPE(ExpectedBaseline)
+
+static qreal expectedBaselineTop(QQuickText *item)
+{
+    QFontMetricsF fm(item->font());
+    return fm.ascent();
+}
+
+static qreal expectedBaselineBottom(QQuickText *item)
+{
+    QFontMetricsF fm(item->font());
+    return item->height() - item->contentHeight() + fm.ascent();
+}
+
+static qreal expectedBaselineCenter(QQuickText *item)
+{
+    QFontMetricsF fm(item->font());
+    return ((item->height() - item->contentHeight()) / 2) + fm.ascent();
+}
+
+static qreal expectedBaselineBold(QQuickText *item)
+{
+    QFont font = item->font();
+    font.setBold(true);
+    QFontMetricsF fm(font);
+    return fm.ascent();
+}
+
+static qreal expectedBaselineImage(QQuickText *item)
+{
+    QFontMetricsF fm(item->font());
+    // The line is positioned so the bottom of the line is aligned with the bottom of the image,
+    // or image height - line height and the baseline is line position + ascent.  Because
+    // QTextLine's height is rounded up this can give slightly different results to image height
+    // - descent.
+    return 181 - qCeil(fm.height()) + fm.ascent();
+}
+
+static qreal expectedBaselineCustom(QQuickText *item)
+{
+    QFontMetricsF fm(item->font());
+    return 16 + fm.ascent();
+}
+
+static qreal expectedBaselineScaled(QQuickText *item)
+{
+    QFont font = item->font();
+    QTextLayout layout(item->text().replace(QLatin1Char('\n'), QChar::LineSeparator));
+    do {
+        layout.setFont(font);
+        qreal width = 0;
+        layout.beginLayout();
+        for (QTextLine line = layout.createLine(); line.isValid(); line = layout.createLine()) {
+            line.setLineWidth(FLT_MAX);
+            width = qMax(line.naturalTextWidth(), width);
+        }
+        layout.endLayout();
+
+        if (width < item->width()) {
+            QFontMetricsF fm(layout.font());
+            return fm.ascent();
+        }
+        font.setPointSize(font.pointSize() - 1);
+    } while (font.pointSize() > 0);
+    return 0;
+}
+
+static qreal expectedBaselineFixedBottom(QQuickText *item)
+{
+    QFontMetricsF fm(item->font());
+    qreal dy = item->text().contains(QLatin1Char('\n'))
+            ? 160
+            : 180;
+    return dy + fm.ascent();
+}
+
+static qreal expectedBaselineProportionalBottom(QQuickText *item)
+{
+    QFontMetricsF fm(item->font());
+    qreal dy = item->text().contains(QLatin1Char('\n'))
+            ? 200 - (qCeil(fm.height()) * 3)
+            : 200 - (qCeil(fm.height()) * 1.5);
+    return dy + fm.ascent();
+}
+
+void tst_qquicktext::baselineOffset_data()
+{
+    qRegisterMetaType<ExpectedBaseline>();
+    QTest::addColumn<QString>("text");
+    QTest::addColumn<QString>("wrappedText");
+    QTest::addColumn<QByteArray>("bindings");
+    QTest::addColumn<ExpectedBaseline>("expectedBaseline");
+    QTest::addColumn<ExpectedBaseline>("expectedBaselineEmpty");
+
+    QTest::newRow("top align")
+            << "hello world"
+            << "hello\nworld"
+            << QByteArray("height: 200; verticalAlignment: Text.AlignTop")
+            << &expectedBaselineTop
+            << &expectedBaselineTop;
+    QTest::newRow("bottom align")
+            << "hello world"
+            << "hello\nworld"
+            << QByteArray("height: 200; verticalAlignment: Text.AlignBottom")
+            << &expectedBaselineBottom
+            << &expectedBaselineBottom;
+    QTest::newRow("center align")
+            << "hello world"
+            << "hello\nworld"
+            << QByteArray("height: 200; verticalAlignment: Text.AlignVCenter")
+            << &expectedBaselineCenter
+            << &expectedBaselineCenter;
+
+    QTest::newRow("bold")
+            << "<b>hello world</b>"
+            << "<b>hello<br/>world</b>"
+            << QByteArray("height: 200")
+            << &expectedBaselineTop
+            << &expectedBaselineBold;
+
+    QTest::newRow("richText")
+            << "<b>hello world</b>"
+            << "<b>hello<br/>world</b>"
+            << QByteArray("height: 200; textFormat: Text.RichText")
+            << &expectedBaselineTop
+            << &expectedBaselineTop;
+
+    QTest::newRow("elided")
+            << "hello world"
+            << "hello\nworld"
+            << QByteArray("width: 20; height: 8; elide: Text.ElideRight")
+            << &expectedBaselineTop
+            << &expectedBaselineTop;
+
+    QTest::newRow("elided bottom align")
+            << "hello world"
+            << "hello\nworld!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!"
+            << QByteArray("width: 200; height: 200; elide: Text.ElideRight; verticalAlignment: Text.AlignBottom")
+            << &expectedBaselineBottom
+            << &expectedBaselineBottom;
+
+    QTest::newRow("image")
+            << "hello <img src=\"images/heart200.png\" /> world"
+            << "hello <img src=\"images/heart200.png\" /><br/>world"
+            << QByteArray("height: 200\n; baseUrl: \"") + testFileUrl("reference").toEncoded() + QByteArray("\"")
+            << &expectedBaselineImage
+            << &expectedBaselineTop;
+
+    QTest::newRow("customLine")
+            << "hello world"
+            << "hello\nworld"
+            << QByteArray("height: 200; onLineLaidOut: line.y += 16")
+            << &expectedBaselineCustom
+            << &expectedBaselineCustom;
+
+    QTest::newRow("scaled font")
+            << "hello world"
+            << "hello\nworld"
+            << QByteArray("width: 200; minimumPointSize: 1; font.pointSize: 64; fontSizeMode: Text.HorizontalFit")
+            << &expectedBaselineScaled
+            << &expectedBaselineTop;
+
+    QTest::newRow("fixed line height top align")
+            << "hello world"
+            << "hello\nworld"
+            << QByteArray("height: 200; lineHeightMode: Text.FixedHeight; lineHeight: 20; verticalAlignment: Text.AlignTop")
+            << &expectedBaselineTop
+            << &expectedBaselineTop;
+
+    QTest::newRow("fixed line height bottom align")
+            << "hello world"
+            << "hello\nworld"
+            << QByteArray("height: 200; lineHeightMode: Text.FixedHeight; lineHeight: 20; verticalAlignment: Text.AlignBottom")
+            << &expectedBaselineFixedBottom
+            << &expectedBaselineFixedBottom;
+
+    QTest::newRow("proportional line height top align")
+            << "hello world"
+            << "hello\nworld"
+            << QByteArray("height: 200; lineHeightMode: Text.ProportionalHeight; lineHeight: 1.5; verticalAlignment: Text.AlignTop")
+            << &expectedBaselineTop
+            << &expectedBaselineTop;
+
+    QTest::newRow("proportional line height bottom align")
+            << "hello world"
+            << "hello\nworld"
+            << QByteArray("height: 200; lineHeightMode: Text.ProportionalHeight; lineHeight: 1.5; verticalAlignment: Text.AlignBottom")
+            << &expectedBaselineProportionalBottom
+            << &expectedBaselineProportionalBottom;
+}
+
+void tst_qquicktext::baselineOffset()
+{
+    QFETCH(QString, text);
+    QFETCH(QString, wrappedText);
+    QFETCH(QByteArray, bindings);
+    QFETCH(ExpectedBaseline, expectedBaseline);
+    QFETCH(ExpectedBaseline, expectedBaselineEmpty);
+
+    QQmlComponent component(&engine);
+    component.setData(
+            "import QtQuick 2.0\n"
+            "Text {\n"
+                + bindings + "\n"
+            "}", QUrl());
+
+    QScopedPointer<QObject> object(component.create());
+
+    QQuickText *item = qobject_cast<QQuickText *>(object.data());
+    QVERIFY(item);
+
+    {
+        qreal baseline = expectedBaselineEmpty(item);
+
+        QCOMPARE(item->baselineOffset(), baseline);
+
+        item->setText(text);
+        if (expectedBaseline != expectedBaselineEmpty)
+            baseline = expectedBaseline(item);
+
+        QCOMPARE(item->baselineOffset(), baseline);
+
+        item->setText(wrappedText);
+        QCOMPARE(item->baselineOffset(), expectedBaseline(item));
+    }
+
+    QFont font = item->font();
+    font.setPointSize(font.pointSize() + 8);
+
+    {
+        QCOMPARE(item->baselineOffset(), expectedBaseline(item));
+
+        item->setText(text);
+        qreal baseline = expectedBaseline(item);
+        QCOMPARE(item->baselineOffset(), baseline);
+
+        item->setText(QString());
+        if (expectedBaselineEmpty != expectedBaseline)
+            baseline = expectedBaselineEmpty(item);
+
+        QCOMPARE(item->baselineOffset(), baseline);
+    }
+}
+
 QTEST_MAIN(tst_qquicktext)
 
 #include "tst_qquicktext.moc"