From f4afe4934819a7f0fb9754b9bb08fb1acb818058 Mon Sep 17 00:00:00 2001
From: Shinichi Okada <shinichi.okada@qt.io>
Date: Tue, 17 Nov 2020 14:15:50 +0900
Subject: [PATCH 08/28] QML Text doesn't reset lineCount when text is empty

lineCount is not reset when replacing a multi-line QML Text 'text'
property with an "" empty string. Also, the lineCountChanged signal is
not emitted

Task-number: QTBUG-84458
Change-Id: Ic3c02e6a90e6675eadbaafc6af6ab0356ee98123
Reviewed-by: Fabian Kosmale <fabian.kosmale@qt.io>
(cherry picked from commit ae1b9c6d94001411efeef600e22638906e0fa990)
Reviewed-by: Qt Cherry-pick Bot <cherrypick_bot@qt-project.org>
---
 src/quick/items/qquicktext.cpp                |  2 +
 .../auto/quick/qquicktext/tst_qquicktext.cpp  | 37 +++++++++++++++++++
 2 files changed, 39 insertions(+)

diff --git a/src/quick/items/qquicktext.cpp b/src/quick/items/qquicktext.cpp
index 90469ee82b..581ab9f76a 100644
--- a/src/quick/items/qquicktext.cpp
+++ b/src/quick/items/qquicktext.cpp
@@ -398,6 +398,8 @@ void QQuickTextPrivate::updateSize()
         layedOutTextRect = QRectF(0, 0, 0, fontHeight);
         advance = QSizeF();
         signalSizeChange(previousSize);
+        lineCount = 1;
+        emit q->lineCountChanged();
         updateType = UpdatePaintNode;
         q->update();
         return;
diff --git a/tests/auto/quick/qquicktext/tst_qquicktext.cpp b/tests/auto/quick/qquicktext/tst_qquicktext.cpp
index 42fdbea58d..308c6b5091 100644
--- a/tests/auto/quick/qquicktext/tst_qquicktext.cpp
+++ b/tests/auto/quick/qquicktext/tst_qquicktext.cpp
@@ -2243,6 +2243,43 @@ void tst_qquicktext::lineCount()
     QCOMPARE(myText->lineCount(), 2);
     QCOMPARE(myText->truncated(), true);
     QCOMPARE(myText->maximumLineCount(), 2);
+
+    // QTBUG-84458
+    myText->resetMaximumLineCount();
+    myText->setText("qqqqq\nqqqqq");
+    QCOMPARE(myText->lineCount(), 2);
+    myText->setText("qqqqq\nqqqqq\nqqqqq");
+    QCOMPARE(myText->lineCount(), 3);
+    myText->setText("");
+    QCOMPARE(myText->lineCount(), 1);
+
+    myText->setText("qqqqq\nqqqqq\nqqqqq");
+    QCOMPARE(myText->lineCount(), 3);
+    myText->setFontSizeMode(QQuickText::HorizontalFit);
+    myText->setText("");
+    QCOMPARE(myText->lineCount(), 1);
+
+    myText->setText("qqqqq\nqqqqq\nqqqqq");
+    QCOMPARE(myText->lineCount(), 3);
+    myText->setFontSizeMode(QQuickText::VerticalFit);
+    myText->setText("");
+    QCOMPARE(myText->lineCount(), 1);
+
+    myText->setText("qqqqq\nqqqqq\nqqqqq");
+    QCOMPARE(myText->lineCount(), 3);
+    myText->setFontSizeMode(QQuickText::Fit);
+    myText->setText("");
+    QCOMPARE(myText->lineCount(), 1);
+
+    QScopedPointer<QQuickView> layoutWindow(createView(testFile("lineLayoutHAlign.qml")));
+    QQuickText *lineLaidOut = layoutWindow->rootObject()->findChild<QQuickText*>("myText");
+    QVERIFY(lineLaidOut != nullptr);
+
+    lineLaidOut->setText("qqqqq\nqqqqq\nqqqqq");
+    QCOMPARE(lineLaidOut->lineCount(), 3);
+    lineLaidOut->setFontSizeMode(QQuickText::FixedSize);
+    lineLaidOut->setText("");
+    QCOMPARE(lineLaidOut->lineCount(), 1);
 }
 
 void tst_qquicktext::lineHeight()
-- 
2.31.1