The first step is to run PepperMill on your application and then update your build files. If your project is already using CMake this should be a quick process and pretty simple. Once these two steps are done there may be additional modifications which need to be done by hand or a few simple search and replace passes. The following notes were collated from other developers who have been through the migration.

Run PepperMill

Modifications to your CMake build files

change your build files to enable C++17
remove any lines which refer to AUTOMOC
replace any lines which refer to AUTOUIC with the following syntax
// run uic to generate source

COPPERSPICE_RESOURCES(

${CMAKE_CURRENT_SOURCE_DIR}/../forms/mainwindow.ui

)
update the call to find_package
// prior syntax

find_package(Qt4 REQUIRED QtCore QtGui QtMultimedia QtNetwork QtSql)

// replacement syntax

find_package(CopperSpice REQUIRED)

update all library references in the style shown below

Prior Syntax	Replacement Syntax
Qt4::QtCore	CopperSpice::CsCore
Qt4::QtGui	CopperSpice::CsGui
Qt4::QtMultimedia	CopperSpice::CsMultimedia
Qt4::QtNetwork	CopperSpice::CsNetwork
Qt4::QtSql	CopperSpice::CsSql

list the libraries and plugins your application will require at run time
these calls are added in your root project CMakeLists.txt file
// copies the specified CS libraries to your project install prefix

cs_copy_library(CsCore)

cs_copy_library(CsGui)

cs_copy_library(CsMultimedia)

cs_copy_library(CsNetwork)

cs_copy_library(CsOpenGL)

cs_copy_library(CsScript)

cs_copy_library(CsSql)

cs_copy_library(CsSvg)

cs_copy_library(CsXml)

cs_copy_library(CsXmlPatterns)

// installs the platform Gui plugins

cs_copy_plugins(CsGui)

// installs the platform Printer driver plugin

cs_copy_plugins(CsPrinterDriver)

// installs the platform Multimedia plugins

cs_copy_plugins(CsMultimedia)

// installs the OpenGL plugin

cs_copy_plugins(CsOpenGL)

// installs the MySQL/MariaDB plugin

cs_copy_plugins(CsSqlMySql)

// installs the PostgreSQL plugin

cs_copy_plugins(CsSqlPsql)

// installs the plugin for loading SVG images

cs_copy_plugins(CsImageFormatsSvg)
if your project contains a .qrc file add the following
COPPERSPICE_RESOURCES(

${CMAKE_CURRENT_SOURCE_DIR}/src/some_file.qrc

)
if your project contains a .ui file add the following
COPPERSPICE_RESOURCES(

${CMAKE_CURRENT_SOURCE_DIR}/src/mainwindow.ui

)
For an example refer to this project cmake build file

Source code changes: Strings
- QString is a typedef for QString8
  - obsolete or unnecessary methods were removed Removed or Unsupported Methods
  - syntax was enhanced or improved Migrating QString Syntax
- QString::isNull() was removed, replace with QString::isEmpty()
- replace toAscii().constData() with toLatin1().constData()
- replace arg() with formatArg(), refer to QStringParser
- replace toInt() with toInteger<int>
- QString::SplitBehavior enum moved to QStringParser
  // prior code
  
  QString::KeepEmptyParts
  
  QString::SkipEmptyParts
  
  // new syntax
  
  QStringParser::KeepEmptyParts
  
  QStringParser::SkipEmptyParts
- add explicit conversion to QString()
  // prior code
  
  QString text = (var == Images::Continuous) ? "Continuous" : "Once";
  
  // new syntax
  
  QString text = (var == Images::Continuous) ? QString("Continuous") : QString("Once");
Source code changes: Languages/Locales
- replace countriesForLanguage() with matchingLocales()
  // prior code
  
  QLocale::Language langId = QLocale::German;
  
  QList<QLocale::Country> countryList = QLocale::countriesForLanguage(langId);
  
  for (auto country : countryList) {
  
  QString label = QLocale::languageToString(langId) + "/" + QLocale::countryToString(country);
  
  // examples will include "German/Germany", "German/Switzerland", "German/Austria", etc
  
  }
  
  // new syntax
  
  QLocale::Language langId = QLocale::German;
  
  QList<QLocale> localeList = QLocale::matchingLocales(langId, QLocale::AnyScript, QLocale::AnyCountry);
  
  for (auto locale : localeList) {
  
  QString label = QLocale::languageToString(langId) + "/" + QLocale::countryToString(locale.country());
  
  // examples will include "German/Germany", "German/Switzerland", "German/Austria", etc
  
  }
Source code changes: General
- replace enum type QFileDialog::Options with QFileDialog::FileDialogOptions
- replace class QRegExp with QRegularExpression
  - detailed information is available in the CS API documentation for Migrating to QRegularExpression
- regular expressions
  QString line = "some text";
  
  // prior syntax
  
  QString str = line.section(QRegularExpression("(\\s)+"), 0, 0);
  
  // new syntax
  
  QString str = QStringParser::section(line, QRegularExpression("(\\s)+", 0, 0));
- replacement for foreach and forever
  // prior syntax
  
  foreach (x, y) {
  
  // new syntax
  
  for (x : y) {
  
  // prior syntax
  
  forever {
  
  // new syntax
  
  while true() {

Source code changes: Enum Change

enum Qt::Modifier removed, use enum Qt::KeyboardModifier

Obsolete	Replace With
Qt::ALT (or Qt::Modifier::ALT)	Qt::KeyboardModifier::AltModifier
Qt::CTRL (or Qt::Modifier::CTRL)	Qt::KeyboardModifier::ControlModifier
Qt::META (or Qt::Modifier::META)	Qt::KeyboardModifier::MetaModifier
Qt::SHIFT (or Qt::Modifier::SHIFT)	Qt::KeyboardModifier::ShiftModifier

Source code changes: Headers

CsCore header file name changes

Obsolete Header	Use these Header File Names
#include <Qt>	#include <qnamespace.h>
#include <qt.h>	#include <qnamespace.h>
#include <QtNamespace>	#include <qnamespace.h>
#include <QtAlgorithms>	#include <qalgorithms.h>
#include <QtGlobal>	#include <qglobal.h>
#include <QtEndian>	#include <qendian.h>

CsMultimedia header file name changes

Obsolete Header Mixed Case Header Name

#include <QMediaServiceProviderPlugin> #include <qmediaservice_provider_plugin.h>

CsNetwork header file name changes

Obsolete Header	Mixed Case Header Name
#include <QNetworkAccessManager>	#include <QAccess_Manager>
	#include <QNetAccess_Manager>

#include <QAbstractNetworkCache>	#include <QAbstract_NetworkCache>
#include <QHttpHeader>	#include <QHttp_Header>
#include <QHttpMultiPart>	#include <QHttp_MultiPart>
#include <QHttpPart>	#include <QHttp_Part>
#include <QNetworkCacheMetaData>	#include <QNetwork_CacheMetaData>
#include <QNetworkCookie>	#include <QNetwork_Cookie>
#include <QNetworkCookieJar>	#include <QNetwork_CookieJar>
#include <QNetworkDiskCache>	#include <QNetwork_DiskCache>
#include <QNetworkReply>	#include <QNetwork_Reply>
#include <QNetworkRequest>	#include <QNetwork_Request>
#include <QSslCertificateExtension>	#include <QSslCertificate_Extension>

Source code changes: QVariant
- QVariant and QMetaType changes as of CopperSpice 1.7
- complete redesign and refactoring of the entire QVariant system
- QVariant uses std::variant for storing its data
- property system returns a QVariant::Type, prior return type was QMetaType::Type
- macro Q_DECLARE_METATYPE(Type) has been changed to CS_DECLARE_METATYPE(Type)
- QMetaType has been removed since it is obsolete
- change QVariant::constData() to call QVariant::getData()
- remove qRegisterMetaTypeStreamOperators<T> since it is obsolete
- change calls to QVariant::isNull()
  - use QVariant::isValid() and invert logic
- changes for qVariantValue or qvariant_cast
  // prior syntax for either call
  
  qVariantValue<T>(data);
  
  qvariant_cast<T>(data);
  
  // new syntax
  
  data.value<T>();
- change for qMetaTypeId
  - metaType id is automatically assigned the first time it is needed
  // prior syntax
  
  qMetaTypeId<QIODevice *>();
  
  // new syntax
  
  QVariant::typeToTypeId<QIODevice *>();
- remove qRegisterMetaType<T> since it is obsolete
  - metaType id is automatically assigned the first time it is needed
Source code changes: QVariant constructors for GUI Enums
- Several enum types which were implicitly convertible to a QVariant must now be explicitly constructed
  
  Enum Types Used in Class
  
  Qt::BrushStyle QBrush
  
  Qt::CursorShape QCursor
  
  Qt::GlobalColor QColor
  
  Qt::PenStyle QPen
  
  // prior syntax
  
  QVariant colorA = Qt::red;
  
  // new syntax
  
  QVariant colorB = QColor(Qt::red);
Source code changes: Signals / Slots
- QObject::receivers() takes one QString as its argument, the SIGNAL macro expands to two strings
  // prior code
  
  myObj::receivers(SIGNAL(yourSignal()));
  
  // new syntax
  
  myObj::receivers(SLOT(yourSignal()));
- if you declared an overloaded Signal or Slot replace the CS_SIGNAL_2() or CS_SLOT_2() macro calls with CS_SIGNAL_OVERLOAD() or CS_SLOT_OVERLOAD()
- for parameters passed to a method with an associated tag, modify the CS_TAG() macro parameter list
Source code changes: Print Settings
- setPageMargins()
  // prior code
  
  printer->setPageMargins(0.00, 0.00, 0.00, 0.00, QPageSize::Unit::Inch);
  
  // new syntax
  
  printer->setPageMargins(QMarginsF(0.00, 0.00, 0.00, 0.00), QPageSize::Unit::Inch);
- enum value QPrinter::Inch should be QPageSize::Unit::Inch
- enum value QPrinter::Letter should be QPageSize::PageSizeId::Letter

Enum Types	Used in Class
Qt::BrushStyle	QBrush
Qt::CursorShape	QCursor
Qt::GlobalColor	QColor
Qt::PenStyle	QPen