1 files changed, 20 insertions, 5 deletions

diff --git a/src/gui/widgets/qplaintextedit.cpp b/src/gui/widgets/qplaintextedit.cpp
index 3d2c4f5..36bac84 100644
--- a/src/gui/widgets/qplaintextedit.cpp
+++ b/src/gui/widgets/qplaintextedit.cpp
@@ -375,11 +375,16 @@ void QPlainTextDocumentLayout::layoutBlock(const QTextBlock &block)
         extraMargin += fm.width(QChar(0x21B5));
     }
     tl->beginLayout();
+    qreal availableWidth = d->width;
+    if (availableWidth <= 0) {
+        availableWidth = INT_MAX; // similar to text edit with pageSize.width == 0
+    }
+    availableWidth -= 2*margin + extraMargin;
     while (1) {
         QTextLine line = tl->createLine();
         if (!line.isValid())
             break;
-        line.setLineWidth(d->width - 2*margin - extraMargin);
+        line.setLineWidth(availableWidth);
 
         height += leading;
         line.setPosition(QPointF(margin, height));
@@ -444,7 +449,7 @@ QPlainTextEditControl::QPlainTextEditControl(QPlainTextEdit *parent)
 void QPlainTextEditPrivate::_q_cursorPositionChanged()
 {
     pageUpDownLastCursorYIsValid = false;
-};
+}
 
 void QPlainTextEditPrivate::_q_verticalScrollbarActionTriggered(int action) {
     if (action == QAbstractSlider::SliderPageStepAdd) {
@@ -560,7 +565,8 @@ QRectF QPlainTextEditControl::blockBoundingRect(const QTextBlock &block) const {
     if (!currentBlock.isValid())
         return QRectF();
     Q_ASSERT(currentBlock.blockNumber() == currentBlockNumber);
-    QPlainTextDocumentLayout *documentLayout = qobject_cast<QPlainTextDocumentLayout*>(document()->documentLayout());
+    QTextDocument *doc = document();
+    QPlainTextDocumentLayout *documentLayout = qobject_cast<QPlainTextDocumentLayout*>(doc->documentLayout());
     Q_ASSERT(documentLayout);
 
     QPointF offset;
@@ -571,13 +577,22 @@ QRectF QPlainTextEditControl::blockBoundingRect(const QTextBlock &block) const {
         offset.ry() += r.height();
         currentBlock = currentBlock.next();
         ++currentBlockNumber;
+        if (!currentBlock.isVisible()) {
+            currentBlock = doc->findBlockByLineNumber(currentBlock.firstLineNumber());
+            currentBlockNumber = currentBlock.blockNumber();
+        }
         r = documentLayout->blockBoundingRect(currentBlock);
     }
     while (currentBlockNumber > blockNumber && offset.y() >= -textEdit->viewport()->height()) {
         currentBlock = currentBlock.previous();
+        --currentBlockNumber;
+        while (!currentBlock.isVisible()) {
+            currentBlock = currentBlock.previous();
+            --currentBlockNumber;
+        }
         if (!currentBlock.isValid())
             break;
-        --currentBlockNumber;
+
         r = documentLayout->blockBoundingRect(currentBlock);
         offset.ry() -= r.height();
     }
@@ -1747,7 +1762,7 @@ void QPlainTextEdit::paintEvent(QPaintEvent *e)
 
     QTextBlock block = firstVisibleBlock();
     qreal maximumWidth = document()->documentLayout()->documentSize().width();
-    
+
     // keep right margin clean from full-width selection
     int maxX = offset.x() + qMax((qreal)viewportRect.width(), maximumWidth)
                - document()->documentMargin();