Added BackwardsScanner::mid(tokenIndex). Mid() returns a substring starting from the position of the given token.

src/libs/cplusplus/BackwardsScanner.cpp

@@ -99,6 +99,12 @@ int BackwardsScanner::startPosition() const
 QString BackwardsScanner::text() const
 { return _text; }
 
+QString BackwardsScanner::mid(int index) const
+{
+    const SimpleToken &firstToken = _tokens.at(index + _offset);
+    return _text.mid(firstToken.begin());
+}
+
 QString BackwardsScanner::text(int index) const
 {
     const SimpleToken &firstToken = _tokens.at(index + _offset);

src/libs/cplusplus/BackwardsScanner.h

@@ -51,9 +51,10 @@ public:
     int startPosition() const;
 
     QString text() const;
+    QString mid(int index) const;
+
     QString text(int index) const;
     QStringRef textRef(int index) const;
-
     // 1-based
     SimpleToken LA(int index) const;
 

src/libs/cplusplus/ExpressionUnderCursor.cpp

@@ -150,7 +150,7 @@ QString ExpressionUnderCursor::operator()(const QTextCursor &cursor)
     if (i == initialSize)
         return QString();
 
-    return scanner.text(i);
+    return scanner.mid(i);
 }
 
 int ExpressionUnderCursor::startOfFunctionCall(const QTextCursor &cursor) const