Add support for QTextCharFormat::underlineColor in highlighers and CSS

When a QSyntaxHighlighter calls setUnderlineColor(), TextEdit will use
that color for underline, overline and strikeout rendering.  Likewise
when Text has textFormat: Text.RichText and the HTML contains CSS styling
specifying text-decoration-color, it will be applied (depending on the
css support in QTextHtmlParser to call setUnderlineColor()).

Added a manual test.

[ChangeLog][QtQuick][TextEdit] When a QSyntaxHighlighter calls
QTextFormat::setUnderlineColor(), or CSS style contains
text-decoration-color, Text and TextEdit will now use that color for
underline, overline and strikeout rendering.

Task-number: QTBUG-87260
Task-number: QTBUG-74572
Task-number: QTBUG-39617
Change-Id: Ia2b564d5366ff67bb5df4f6c9e68ff5773ca5d6a
Reviewed-by: Shawn Rutledge <shawn.rutledge@qt.io>

6 files changed, 394 insertions, 0 deletions

diff --git a/tests/manual/syntaxhighlighter/app.qml b/tests/manual/syntaxhighlighter/app.qml
new file mode 100644
index 0000000000..5ad775785f
--- /dev/null
+++ b/tests/manual/syntaxhighlighter/app.qml
@@ -0,0 +1,96 @@
+/****************************************************************************
+**
+** Copyright (C) 2021 The Qt Company Ltd.
+** Contact: https://www.qt.io/licensing/
+**
+** This file is part of the manual tests of the Qt Toolkit.
+**
+** $QT_BEGIN_LICENSE:BSD$
+** Commercial License Usage
+** Licensees holding valid commercial Qt licenses may use this file in
+** accordance with the commercial license agreement provided with the
+** Software or, alternatively, in accordance with the terms contained in
+** a written agreement between you and The Qt Company. For licensing terms
+** and conditions see https://www.qt.io/terms-conditions. For further
+** information use the contact form at https://www.qt.io/contact-us.
+**
+** BSD License Usage
+** Alternatively, you may use this file under the terms of the BSD license
+** as follows:
+**
+** "Redistribution and use in source and binary forms, with or without
+** modification, are permitted provided that the following conditions are
+** met:
+**   * Redistributions of source code must retain the above copyright
+**     notice, this list of conditions and the following disclaimer.
+**   * Redistributions in binary form must reproduce the above copyright
+**     notice, this list of conditions and the following disclaimer in
+**     the documentation and/or other materials provided with the
+**     distribution.
+**   * Neither the name of The Qt Company Ltd nor the names of its
+**     contributors may be used to endorse or promote products derived
+**     from this software without specific prior written permission.
+**
+**
+** THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+** "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+** LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+** A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+** OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+** SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+** LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+** DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+** THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+** (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+** OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE."
+**
+** $QT_END_LICENSE$
+**
+****************************************************************************/
+
+import QtQuick
+import QtQuick.Controls
+import Highlighter
+
+TextEdit {
+    id: textEdit
+    width: 420; height: 200
+    text: '<p>Try the different <span style="text-decoration: underline overline; text-decoration-color: green;">highlight</span> styles.' +
+          "The keyword is 'char'.</p><code>char * test;</code>"
+    textFormat: TextEdit.RichText
+    leftPadding: 6; topPadding: 6
+
+    DocumentHighlighter {
+        id: highlighter
+        document: textEdit.textDocument
+        style: sb.value
+    }
+
+    SpinBox {
+        id: sb
+        anchors.bottom: parent.bottom
+        anchors.margins: 6
+        x: 6
+        to: items.length - 1
+        value: 0
+        width: 200
+
+        property var items: ["Bold", "Cyanderlined", "Misspelled", "Gaudy", "Orangeout"]
+
+        validator: RegularExpressionValidator {
+            regularExpression: new RegExp("(Bold|Cyanderlined|Misspelled|Gaudy|Orangeout)", "i")
+        }
+
+        textFromValue: function(value) {
+            return items[value];
+        }
+
+        valueFromText: function(text) {
+            for (var i = 0; i < items.length; ++i) {
+                if (items[i].toLowerCase().indexOf(text.toLowerCase()) === 0)
+                    return i
+            }
+            return sb.value
+        }
+    }
+}
diff --git a/tests/manual/syntaxhighlighter/documenthighlighter.cpp b/tests/manual/syntaxhighlighter/documenthighlighter.cpp
new file mode 100644
index 0000000000..f5f3471074
--- /dev/null
+++ b/tests/manual/syntaxhighlighter/documenthighlighter.cpp
@@ -0,0 +1,124 @@
+/****************************************************************************
+**
+** Copyright (C) 2021 The Qt Company Ltd.
+** Contact: https://www.qt.io/licensing/
+**
+** This file is part of the manual tests of the Qt Toolkit.
+**
+** $QT_BEGIN_LICENSE:BSD$
+** Commercial License Usage
+** Licensees holding valid commercial Qt licenses may use this file in
+** accordance with the commercial license agreement provided with the
+** Software or, alternatively, in accordance with the terms contained in
+** a written agreement between you and The Qt Company. For licensing terms
+** and conditions see https://www.qt.io/terms-conditions. For further
+** information use the contact form at https://www.qt.io/contact-us.
+**
+** BSD License Usage
+** Alternatively, you may use this file under the terms of the BSD license
+** as follows:
+**
+** "Redistribution and use in source and binary forms, with or without
+** modification, are permitted provided that the following conditions are
+** met:
+**   * Redistributions of source code must retain the above copyright
+**     notice, this list of conditions and the following disclaimer.
+**   * Redistributions in binary form must reproduce the above copyright
+**     notice, this list of conditions and the following disclaimer in
+**     the documentation and/or other materials provided with the
+**     distribution.
+**   * Neither the name of The Qt Company Ltd nor the names of its
+**     contributors may be used to endorse or promote products derived
+**     from this software without specific prior written permission.
+**
+**
+** THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+** "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+** LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+** A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+** OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+** SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+** LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+** DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+** THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+** (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+** OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE."
+**
+** $QT_END_LICENSE$
+**
+****************************************************************************/
+
+#include "documenthighlighter.h"
+#include <QtQuick/QQuickTextDocument>
+
+Highlighter::Highlighter(QTextDocument *parent, int underlineTest)
+    : QSyntaxHighlighter(parent)
+{
+    m_testRegex.setPattern("char");
+}
+
+void Highlighter::highlightBlock(const QString &text)
+{
+    QTextCharFormat fmt;
+    if (m_style > 0)
+        fmt.setForeground(Qt::darkBlue);
+    fmt.setFontWeight(QFont::Bold);
+    switch (m_style) {
+    case 1:
+        fmt.setFontUnderline(true);
+        fmt.setUnderlineColor(QColor("cyan"));
+        break;
+    case 2:
+        fmt.setFontUnderline(true);
+        fmt.setUnderlineColor(QColor("red"));
+        // fmt.setUnderlineStyle(QTextCharFormat::WaveUnderline); // not supported yet: QTBUG-39617
+        break;
+    case 3:
+        fmt.setFontOverline(true);
+        fmt.setFontUnderline(true);
+        fmt.setUnderlineColor(QColor("green"));
+        fmt.setBackground(QColor("lightgreen"));
+        fmt.setForeground(Qt::magenta);
+        fmt.setFontItalic(true);
+        fmt.setFontStretch(200);
+        fmt.setFontPointSize(14);
+        fmt.setFontStyleHint(QFont::Decorative); // seems ignored in practice
+        break;
+    case 4:
+        fmt.setFontStrikeOut(true);
+        fmt.setUnderlineColor(QColor("orange"));
+        fmt.setFontCapitalization(QFont::Capitalization::SmallCaps);
+        break;
+    }
+
+    QRegularExpressionMatchIterator matchIterator = m_testRegex.globalMatch(text);
+    while (matchIterator.hasNext()) {
+        QRegularExpressionMatch match = matchIterator.next();
+        setFormat(match.capturedStart(), match.capturedLength(), fmt);
+    }
+}
+
+DocumentHighlighter::DocumentHighlighter(QObject *parent)
+    : QObject(parent) {}
+
+void DocumentHighlighter::setDocument(QQuickTextDocument *document)
+{
+    if (m_document == document)
+        return;
+
+    m_document = document;
+    m_highlighter.setDocument(m_document->textDocument());
+    m_highlighter.rehighlight();
+
+    emit documentChanged();
+}
+
+void DocumentHighlighter::setStyle(int style)
+{
+    if (m_highlighter.m_style == style)
+        return;
+
+    m_highlighter.m_style = style;
+    m_highlighter.rehighlight();
+    emit styleChanged();
+}
diff --git a/tests/manual/syntaxhighlighter/documenthighlighter.h b/tests/manual/syntaxhighlighter/documenthighlighter.h
new file mode 100644
index 0000000000..354fb3be4d
--- /dev/null
+++ b/tests/manual/syntaxhighlighter/documenthighlighter.h
@@ -0,0 +1,96 @@
+/****************************************************************************
+**
+** Copyright (C) 2021 The Qt Company Ltd.
+** Contact: https://www.qt.io/licensing/
+**
+** This file is part of the manual tests of the Qt Toolkit.
+**
+** $QT_BEGIN_LICENSE:BSD$
+** Commercial License Usage
+** Licensees holding valid commercial Qt licenses may use this file in
+** accordance with the commercial license agreement provided with the
+** Software or, alternatively, in accordance with the terms contained in
+** a written agreement between you and The Qt Company. For licensing terms
+** and conditions see https://www.qt.io/terms-conditions. For further
+** information use the contact form at https://www.qt.io/contact-us.
+**
+** BSD License Usage
+** Alternatively, you may use this file under the terms of the BSD license
+** as follows:
+**
+** "Redistribution and use in source and binary forms, with or without
+** modification, are permitted provided that the following conditions are
+** met:
+**   * Redistributions of source code must retain the above copyright
+**     notice, this list of conditions and the following disclaimer.
+**   * Redistributions in binary form must reproduce the above copyright
+**     notice, this list of conditions and the following disclaimer in
+**     the documentation and/or other materials provided with the
+**     distribution.
+**   * Neither the name of The Qt Company Ltd nor the names of its
+**     contributors may be used to endorse or promote products derived
+**     from this software without specific prior written permission.
+**
+**
+** THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+** "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+** LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+** A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+** OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+** SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+** LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+** DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+** THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+** (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+** OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE."
+**
+** $QT_END_LICENSE$
+**
+****************************************************************************/
+
+#ifndef DOCUMENTHIGHLIGHTER_H
+#define DOCUMENTHIGHLIGHTER_H
+
+#include <QSyntaxHighlighter>
+#include <QTextCharFormat>
+#include <QRegularExpression>
+#include <QQuickTextDocument>
+#include <QtQml>
+
+class Highlighter : public QSyntaxHighlighter
+{
+public:
+    Highlighter(QTextDocument *parent = nullptr, int underlineTest = 0);
+
+    void highlightBlock(const QString &text) override;
+
+    QRegularExpression m_testRegex;
+    int m_style = 0;
+};
+
+class DocumentHighlighter : public QObject
+{
+    Q_OBJECT
+    Q_PROPERTY(QQuickTextDocument *document READ document WRITE setDocument NOTIFY documentChanged)
+    Q_PROPERTY(int style READ style WRITE setStyle NOTIFY styleChanged)
+    QML_ELEMENT
+
+public:
+    DocumentHighlighter(QObject *parent = nullptr);
+
+    QQuickTextDocument *document() const { return m_document; }
+    void setDocument(QQuickTextDocument * document);
+
+    int style() const { return m_highlighter.m_style; }
+    void setStyle(int style);
+
+signals:
+    void documentChanged();
+    void styleChanged();
+
+private:
+    QQuickTextDocument *m_document = nullptr;
+    Highlighter m_highlighter;
+};
+
+#endif // DOCUMENTHIGHLIGHTER_H
diff --git a/tests/manual/syntaxhighlighter/main.cpp b/tests/manual/syntaxhighlighter/main.cpp
new file mode 100644
index 0000000000..be18034923
--- /dev/null
+++ b/tests/manual/syntaxhighlighter/main.cpp
@@ -0,0 +1,63 @@
+/****************************************************************************
+**
+** Copyright (C) 2021 The Qt Company Ltd.
+** Contact: https://www.qt.io/licensing/
+**
+** This file is part of the manual tests of the Qt Toolkit.
+**
+** $QT_BEGIN_LICENSE:BSD$
+** Commercial License Usage
+** Licensees holding valid commercial Qt licenses may use this file in
+** accordance with the commercial license agreement provided with the
+** Software or, alternatively, in accordance with the terms contained in
+** a written agreement between you and The Qt Company. For licensing terms
+** and conditions see https://www.qt.io/terms-conditions. For further
+** information use the contact form at https://www.qt.io/contact-us.
+**
+** BSD License Usage
+** Alternatively, you may use this file under the terms of the BSD license
+** as follows:
+**
+** "Redistribution and use in source and binary forms, with or without
+** modification, are permitted provided that the following conditions are
+** met:
+**   * Redistributions of source code must retain the above copyright
+**     notice, this list of conditions and the following disclaimer.
+**   * Redistributions in binary form must reproduce the above copyright
+**     notice, this list of conditions and the following disclaimer in
+**     the documentation and/or other materials provided with the
+**     distribution.
+**   * Neither the name of The Qt Company Ltd nor the names of its
+**     contributors may be used to endorse or promote products derived
+**     from this software without specific prior written permission.
+**
+**
+** THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+** "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+** LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+** A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+** OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+** SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+** LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+** DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+** THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+** (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+** OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE."
+**
+** $QT_END_LICENSE$
+**
+****************************************************************************/
+
+#include <QtQuick/QQuickView>
+#include <QGuiApplication>
+#include "documenthighlighter.h"
+
+int main(int argc, char *argv[])
+{
+    QGuiApplication app(argc, argv);
+    QQuickView view;
+    view.setResizeMode(QQuickView::SizeRootObjectToView);
+    view.setSource(QUrl("qrc:///app.qml"));
+    view.show();
+    return app.exec();
+}
diff --git a/tests/manual/syntaxhighlighter/syntaxhighlighter.pro b/tests/manual/syntaxhighlighter/syntaxhighlighter.pro
new file mode 100644
index 0000000000..e364936dbe
--- /dev/null
+++ b/tests/manual/syntaxhighlighter/syntaxhighlighter.pro
@@ -0,0 +1,10 @@
+QT += qml quick
+
+HEADERS += documenthighlighter.h
+SOURCES += main.cpp \
+           documenthighlighter.cpp
+
+RESOURCES += syntaxhighlighter.qrc
+CONFIG += qmltypes
+QML_IMPORT_NAME = Highlighter
+QML_IMPORT_MAJOR_VERSION = 1
diff --git a/tests/manual/syntaxhighlighter/syntaxhighlighter.qrc b/tests/manual/syntaxhighlighter/syntaxhighlighter.qrc
new file mode 100644
index 0000000000..f1168aef3b
--- /dev/null
+++ b/tests/manual/syntaxhighlighter/syntaxhighlighter.qrc
@@ -0,0 +1,5 @@
+<RCC>
+    <qresource prefix="/">
+        <file>app.qml</file>
+    </qresource>
+</RCC>