1 files changed, 126 insertions, 0 deletions
diff --git a/src/shared/lsp/textutils.cpp b/src/shared/lsp/textutils.cpp
new file mode 100644
index 000000000..1c0bff9d0
--- /dev/null
+++ b/src/shared/lsp/textutils.cpp
@@ -0,0 +1,126 @@
+// Copyright (C) 2016 The Qt Company Ltd.
+// SPDX-License-Identifier: LicenseRef-Qt-Commercial OR GPL-3.0-only WITH Qt-GPL-exception-1.0
+
+#include "textutils.h"
+
+#include <tools/qbsassert.h>
+
+#include <QRegularExpression>
+#include <QtDebug>
+
+namespace lsp::Utils::Text {
+
+bool Position::operator==(const Position &other) const
+{
+    return line == other.line && column == other.column;
+}
+
+/*!
+    Returns the text position of a \a fileName and sets the \a postfixPos if
+    it can find a positional postfix.
+
+    The following patterns are supported: \c {filepath.txt:19},
+    \c{filepath.txt:19:12}, \c {filepath.txt+19},
+    \c {filepath.txt+19+12}, and \c {filepath.txt(19)}.
+*/
+
+Position Position::fromFileName(QStringView fileName, int &postfixPos)
+{
+    static const auto regexp = QRegularExpression("[:+](\\d+)?([:+](\\d+)?)?$");
+    // (10) MSVC-style
+    static const auto vsRegexp = QRegularExpression("[(]((\\d+)[)]?)?$");
+    const QRegularExpressionMatch match = regexp.match(fileName);
+    Position pos;
+    if (match.hasMatch()) {
+        postfixPos = match.capturedStart(0);
+        if (match.lastCapturedIndex() > 0) {
+            pos.line = match.captured(1).toInt();
+            if (match.lastCapturedIndex() > 2) // index 2 includes the + or : for the column number
+                pos.column = match.captured(3).toInt() - 1; //column is 0 based, despite line being 1 based
+        }
+    } else {
+        const QRegularExpressionMatch vsMatch = vsRegexp.match(fileName);
+        postfixPos = vsMatch.capturedStart(0);
+        if (vsMatch.lastCapturedIndex() > 1) // index 1 includes closing )
+            pos.line = vsMatch.captured(2).toInt();
+    }
+    if (pos.line > 0 && pos.column < 0)
+        pos.column = 0; // if we got a valid line make sure to return a valid TextPosition
+    return pos;
+}
+
+int Range::length(const QString &text) const
+{
+    if (end.line < begin.line)
+        return -1;
+
+    if (begin.line == end.line)
+        return end.column - begin.column;
+
+    int index = 0;
+    int currentLine = 1;
+    while (currentLine < begin.line) {
+        index = text.indexOf(QChar::LineFeed, index);
+        if (index < 0)
+            return -1;
+        ++index;
+        ++currentLine;
+    }
+    const int beginIndex = index + begin.column;
+    while (currentLine < end.line) {
+        index = text.indexOf(QChar::LineFeed, index);
+        if (index < 0)
+            return -1;
+        ++index;
+        ++currentLine;
+    }
+    return index + end.column - beginIndex;
+}
+
+bool Range::operator==(const Range &other) const
+{
+    return begin == other.begin && end == other.end;
+}
+
+QString utf16LineTextInUtf8Buffer(const QByteArray &utf8Buffer, int currentUtf8Offset)
+{
+    const int lineStartUtf8Offset = currentUtf8Offset
+                                        ? (utf8Buffer.lastIndexOf('\n', currentUtf8Offset - 1) + 1)
+                                        : 0;
+    const int lineEndUtf8Offset = utf8Buffer.indexOf('\n', currentUtf8Offset);
+    return QString::fromUtf8(
+        utf8Buffer.mid(lineStartUtf8Offset, lineEndUtf8Offset - lineStartUtf8Offset));
+}
+
+static bool isByteOfMultiByteCodePoint(unsigned char byte)
+{
+    return byte & 0x80; // Check if most significant bit is set
+}
+
+bool utf8AdvanceCodePoint(const char *&current)
+{
+    if (Q_UNLIKELY(*current == '\0'))
+        return false;
+
+    // Process multi-byte UTF-8 code point (non-latin1)
+    if (Q_UNLIKELY(isByteOfMultiByteCodePoint(*current))) {
+        unsigned trailingBytesCurrentCodePoint = 1;
+        for (unsigned char c = (*current) << 2; isByteOfMultiByteCodePoint(c); c <<= 1)
+            ++trailingBytesCurrentCodePoint;
+        current += trailingBytesCurrentCodePoint + 1;
+
+    // Process single-byte UTF-8 code point (latin1)
+    } else {
+        ++current;
+    }
+
+    return true;
+}
+
+QDebug &operator<<(QDebug &stream, const Position &pos)
+{
+    stream << "line: " << pos.line << ", column: " << pos.column;
+    return stream;
+}
+
+} // namespace Utils::Text