Old-style wizards: Handle line continuation in license templates

This is necessary to have the same template work in the old-style
wizards and the JSON wizard, which supports inserting \n, \t as well
as line continuation for everything.

Change-Id: I11c310998b92650003206484de8f1ecfc6000034
Reviewed-by: Orgad Shaneh <orgads@gmail.com>

src/plugins/cpptools/abstracteditorsupport.cpp

@@ -63,7 +63,30 @@ QString AbstractEditorSupport::licenseTemplate(const QString &file, const QStrin
     expander.registerVariable("Cpp:License:ClassName", tr("The class name"),
                               [className]() { return className; });
 
-    return expander.expand(license);
+    QString out = expander.expand(license);
+    // Expand \n, \t and handle line continuation:
+    QString result;
+    result.reserve(out.count());
+    bool isEscaped = false;
+    for (int i = 0; i < out.count(); ++i) {
+        const QChar c = out.at(i);
+
+        if (isEscaped) {
+            if (c == QLatin1Char('n'))
+                result.append(QLatin1Char('\n'));
+            else if (c == QLatin1Char('t'))
+                result.append(QLatin1Char('\t'));
+            else if (c != QLatin1Char('\n'))
+                result.append(c);
+            isEscaped = false;
+        } else {
+            if (c == QLatin1Char('\\'))
+                isEscaped = true;
+            else
+                result.append(c);
+        }
+    }
+    return result;
 }
 
 } // namespace CppTools