shiboken: Centralize most msg* functions in a separate file

This makes it easier to maintain a consistent style,
unclutters the source and allows for re-using formatting helpers.

Change-Id: I4f29637a22afb457f629272e2d86f14bedb36008
Reviewed-by: Cristian Maureira-Fredes <cristian.maureira-fredes@qt.io>
Reviewed-by: Christian Tismer <tismer@stackless.com>

11 files changed, 582 insertions, 260 deletions

diff --git a/sources/shiboken2/ApiExtractor/CMakeLists.txt b/sources/shiboken2/ApiExtractor/CMakeLists.txt
index b67a352f0..b4fd1cb99 100644
--- a/sources/shiboken2/ApiExtractor/CMakeLists.txt
+++ b/sources/shiboken2/ApiExtractor/CMakeLists.txt
@@ -37,6 +37,7 @@ abstractmetabuilder.cpp
 abstractmetalang.cpp
 fileout.cpp
 graph.cpp
+messages.cpp
 reporthandler.cpp
 typeparser.cpp
 typesystem.cpp
diff --git a/sources/shiboken2/ApiExtractor/abstractmetabuilder.cpp b/sources/shiboken2/ApiExtractor/abstractmetabuilder.cpp
index 85bb1b789..251d674a9 100644
--- a/sources/shiboken2/ApiExtractor/abstractmetabuilder.cpp
+++ b/sources/shiboken2/ApiExtractor/abstractmetabuilder.cpp
@@ -27,6 +27,7 @@
 ****************************************************************************/
 
 #include "abstractmetabuilder_p.h"
+#include "messages.h"
 #include "reporthandler.h"
 #include "typedatabase.h"
 
@@ -159,32 +160,6 @@ AbstractMetaEnumList AbstractMetaBuilder::globalEnums() const
     return d->m_globalEnums;
 }
 
-static QString msgNoFunctionForModification(const QString &signature,
-                                            const QString &originalSignature,
-                                            const QString &className,
-                                            const QStringList &possibleSignatures,
-                                            const AbstractMetaFunctionList &allFunctions)
-{
-    QString result;
-    QTextStream str(&result);
-    str << "signature '" << signature << '\'';
-    if (!originalSignature.isEmpty() && originalSignature != signature)
-        str << " (specified as '" << originalSignature << "')";
-    str << " for function modification in '"
-        << className << "' not found.";
-    if (possibleSignatures.isEmpty()) {
-        str << " No candidates were found. Member functions: ";
-        for (int f = 0, size = allFunctions.size(); f < size; ++f) {
-            if (f)
-                str << ", ";
-            str << allFunctions.at(f)->minimalSignature();
-        }
-    } else {
-        str << " Possible candidates: " << possibleSignatures.join(QLatin1String(", "));
-    }
-    return result;
-}
-
 void AbstractMetaBuilderPrivate::checkFunctionModifications()
 {
     const auto &entries = TypeDatabase::instance()->entries();
@@ -863,66 +838,6 @@ AbstractMetaClass *AbstractMetaBuilderPrivate::traverseNamespace(const FileModel
     return metaClass;
 }
 
-template <class Stream>
-static void msgFormatEnumType(Stream &str,
-                              const EnumModelItem &enumItem,
-                              const QString &className)
-{
-    switch (enumItem->enumKind()) {
-    case CEnum:
-        str << "Enum '" << enumItem->qualifiedName().join(colonColon()) << '\'';
-        break;
-    case AnonymousEnum: {
-        const EnumeratorList &values = enumItem->enumerators();
-        str << "Anonymous enum (";
-        switch (values.size()) {
-        case 0:
-            break;
-        case 1:
-            str << values.constFirst()->name();
-            break;
-        case 2:
-            str << values.at(0)->name() << ", " << values.at(1)->name();
-            break;
-        default:
-            str << values.at(0)->name() << ", ... , "
-                << values.at(values.size() - 1)->name();
-            break;
-        }
-        str << ')';
-    }
-        break;
-    case EnumClass:
-        str << "Scoped enum '" << enumItem->qualifiedName().join(colonColon()) << '\'';
-        break;
-    }
-    if (!className.isEmpty())
-        str << " (class: " << className << ')';
-}
-
-static inline QString msgNoEnumTypeEntry(const EnumModelItem &enumItem,
-                                         const QString &className)
-{
-    QString result;
-    QTextStream str(&result);
-    msgFormatEnumType(str, enumItem, className);
-    str << " does not have a type entry";
-    return result;
-}
-
-static QString msgNoEnumTypeConflict(const EnumModelItem &enumItem,
-                                     const QString &className,
-                                     const TypeEntry *t)
-{
-    QString result;
-    QDebug debug(&result); // Use the debug operator for TypeEntry::Type
-    debug.noquote();
-    debug.nospace();
-    msgFormatEnumType(debug, enumItem, className);
-    debug << " is not an enum (type: " << t->type() << ')';
-    return result;
-}
-
 AbstractMetaEnum *AbstractMetaBuilderPrivate::traverseEnum(const EnumModelItem &enumItem,
                                                            AbstractMetaClass *enclosing,
                                                            const QSet<QString> &enumsDeclarations)
@@ -1894,44 +1809,6 @@ static inline QString qualifiedFunctionSignatureWithType(const FunctionModelItem
     result += functionSignature(functionItem);
     return result;
 }
-
-static inline QString msgUnmatchedParameterType(const ArgumentModelItem &arg, int n,
-                                                const QString &why)
-{
-    QString result;
-    QTextStream str(&result);
-    str << "unmatched type '" << arg->type().toString() << "' in parameter #"
-        << (n + 1);
-    if (!arg->name().isEmpty())
-        str << " \"" << arg->name() << '"';
-    str << ": " << why;
-    return result;
-}
-
-static inline QString msgUnmatchedReturnType(const FunctionModelItem &functionItem,
-                                             const QString &why)
-{
-    return QLatin1String("unmatched return type '")
-        + functionItem->type().toString()
-        + QLatin1String("': ") + why;
-}
-
-static QString msgSkippingFunction(const FunctionModelItem &functionItem,
-                                   const QString &signature, const QString &why)
-{
-    QString result;
-    QTextStream str(&result);
-    str << "skipping ";
-    if (functionItem->isAbstract())
-        str << "abstract ";
-    str << "function '" << signature << "', " << why;
-    if (functionItem->isAbstract()) {
-        str << "\nThis will lead to compilation errors due to not "
-               "being able to instantiate the wrapper.";
-    }
-    return result;
-}
-
 static inline AbstractMetaFunction::FunctionType functionTypeFromCodeModel(CodeModel::FunctionType ft)
 {
     AbstractMetaFunction::FunctionType result = AbstractMetaFunction::NormalFunction;
@@ -1960,12 +1837,6 @@ static inline AbstractMetaFunction::FunctionType functionTypeFromCodeModel(CodeM
     return result;
 }
 
-static inline QString msgCannotSetArrayUsage(const QString &function, int i, const QString &reason)
-{
-    return function +  QLatin1String(": Cannot use parameter ") + QString::number(i + 1)
-        + QLatin1String(" as an array: ") + reason;
-}
-
 bool AbstractMetaBuilderPrivate::setArrayArgumentType(AbstractMetaFunction *func,
                                                       const FunctionModelItem &functionItem,
                                                       int i)
@@ -2332,33 +2203,6 @@ static const TypeEntry* findTypeEntryUsingContext(const AbstractMetaClass* metaC
     return type;
 }
 
-static QString msgUnableToTranslateType(const QString &t, const QString &why)
-{
-    return QLatin1String("Unable to translate type \"")
-        + t + QLatin1String("\": ") + why;
-}
-
-static inline QString msgUnableToTranslateType(const TypeInfo &typeInfo,
-                                               const QString &why)
-{
-    return msgUnableToTranslateType(typeInfo.toString(), why);
-}
-
-static inline QString msgCannotFindTypeEntry(const QString &t)
-{
-    return QLatin1String("Cannot find type entry for \"") + t + QLatin1String("\".");
-}
-
-static inline QString msgCannotTranslateTemplateArgument(int i,
-                                                         const TypeInfo &typeInfo,
-                                                         const QString &why)
-{
-    QString result;
-    QTextStream(&result) << "Unable to translate template argument "
-        << (i + 1) << typeInfo.toString() << ": " << why;
-    return result;
-}
-
 AbstractMetaType *AbstractMetaBuilderPrivate::translateType(const TypeInfo &_typei,
                                                             bool resolveType,
                                                             QString *errorMessage)
diff --git a/sources/shiboken2/ApiExtractor/abstractmetalang.cpp b/sources/shiboken2/ApiExtractor/abstractmetalang.cpp
index 4c1b257d6..d289d943d 100644
--- a/sources/shiboken2/ApiExtractor/abstractmetalang.cpp
+++ b/sources/shiboken2/ApiExtractor/abstractmetalang.cpp
@@ -27,6 +27,7 @@
 ****************************************************************************/
 
 #include "abstractmetalang.h"
+#include "messages.h"
 #include "reporthandler.h"
 #include "typedatabase.h"
 #include "typesystem.h"
@@ -748,17 +749,6 @@ bool AbstractMetaFunction::autoDetectAllowThread() const
     return !maybeGetter;
 }
 
-static QString msgDisallowThread(const AbstractMetaFunction *f)
-{
-    QString result;
-    QTextStream str(&result);
-    str <<"Disallowing threads for ";
-    if (auto c = f->declaringClass())
-        str << c->name() << "::";
-    str << f->name() << "().";
-    return result;
-}
-
 bool AbstractMetaFunction::allowThread() const
 {
     using AllowThread = TypeSystem::AllowThread;
diff --git a/sources/shiboken2/ApiExtractor/docparser.cpp b/sources/shiboken2/ApiExtractor/docparser.cpp
index ce089c1f5..99921e7d3 100644
--- a/sources/shiboken2/ApiExtractor/docparser.cpp
+++ b/sources/shiboken2/ApiExtractor/docparser.cpp
@@ -27,6 +27,7 @@
 ****************************************************************************/
 #include "docparser.h"
 #include "abstractmetalang.h"
+#include "messages.h"
 #include "reporthandler.h"
 #include "typesystem.h"
 #include <QtCore/QDebug>
@@ -107,46 +108,6 @@ AbstractMetaFunctionList DocParser::documentableFunctions(const AbstractMetaClas
     return result;
 }
 
-QString DocParser::msgCannotFindDocumentation(const QString &fileName,
-                                          const char *what, const QString &name,
-                                          const QString &query)
-{
-    QString result;
-    QTextStream(&result) << "Cannot find documentation for " << what
-        << ' ' << name << " in:\n    " << QDir::toNativeSeparators(fileName)
-        << "\n  using query:\n    " << query;
-    return result;
-}
-
-QString DocParser::msgCannotFindDocumentation(const QString &fileName,
-                                              const AbstractMetaClass *metaClass,
-                                              const AbstractMetaFunction *function,
-                                              const QString &query)
-{
-    const QString name = metaClass->name() + QLatin1String("::")
-        + function->minimalSignature();
-    return msgCannotFindDocumentation(fileName, "function", name, query);
-}
-
-QString DocParser::msgCannotFindDocumentation(const QString &fileName,
-                                              const AbstractMetaClass *metaClass,
-                                              const AbstractMetaEnum *e,
-                                              const QString &query)
-{
-    return msgCannotFindDocumentation(fileName, "enum",
-                                      metaClass->name() + QLatin1String("::") + e->name(),
-                                      query);
-}
-
-QString DocParser::msgCannotFindDocumentation(const QString &fileName,
-                                              const AbstractMetaClass *metaClass,
-                                              const AbstractMetaField *f,
-                                              const QString &query)
-{
-    return msgCannotFindDocumentation(fileName, "field",
-                                      metaClass->name() + QLatin1String("::") + f->name(),
-                                      query);
-}
 
 #ifdef HAVE_LIBXSLT
 namespace
@@ -187,27 +148,6 @@ static inline bool isXpathDocModification(const DocModification &mod)
     return mod.mode() == TypeSystem::DocModificationXPathReplace;
 }
 
-QString msgXpathDocModificationError(const DocModificationList& mods,
-                                     const QString &what)
-{
-    QString result;
-    QTextStream str(&result);
-    str << "Error when applying modifications (";
-    for (const DocModification &mod : mods) {
-        if (isXpathDocModification(mod)) {
-            str << '"' << mod.xpath() << "\" -> \"";
-            const QString simplified = mod.code().simplified();
-            if (simplified.size() > 20)
-                str << simplified.leftRef(20) << "...";
-            else
-                str << simplified;
-            str << '"';
-        }
-    }
-    str << "): " << what;
-    return result;
-}
-
 QString DocParser::applyDocModifications(const DocModificationList& mods, const QString& xml) const
 {
     if (mods.isEmpty() || xml.isEmpty()
diff --git a/sources/shiboken2/ApiExtractor/docparser.h b/sources/shiboken2/ApiExtractor/docparser.h
index fff71a877..7cbbef28e 100644
--- a/sources/shiboken2/ApiExtractor/docparser.h
+++ b/sources/shiboken2/ApiExtractor/docparser.h
@@ -120,22 +120,6 @@ protected:
 
     static AbstractMetaFunctionList documentableFunctions(const AbstractMetaClass *metaClass);
 
-    static QString msgCannotFindDocumentation(const QString &fileName,
-                                              const char *what, const QString &name,
-                                              const QString &query);
-    static QString msgCannotFindDocumentation(const QString &fileName,
-                                              const AbstractMetaClass *metaClass,
-                                              const AbstractMetaFunction *function,
-                                              const QString &query);
-    static QString msgCannotFindDocumentation(const QString &fileName,
-                                              const AbstractMetaClass *metaClass,
-                                              const AbstractMetaEnum *e,
-                                              const QString &query);
-    static QString msgCannotFindDocumentation(const QString &fileName,
-                                              const AbstractMetaClass *metaClass,
-                                              const AbstractMetaField *f,
-                                              const QString &query);
-
 private:
     QString m_packageName;
     QString m_docDataDir;
diff --git a/sources/shiboken2/ApiExtractor/doxygenparser.cpp b/sources/shiboken2/ApiExtractor/doxygenparser.cpp
index 7a0346cc6..f487b43a7 100644
--- a/sources/shiboken2/ApiExtractor/doxygenparser.cpp
+++ b/sources/shiboken2/ApiExtractor/doxygenparser.cpp
@@ -28,6 +28,7 @@
 
 #include "doxygenparser.h"
 #include "abstractmetalang.h"
+#include "messages.h"
 #include "reporthandler.h"
 #include "typesystem.h"
 
diff --git a/sources/shiboken2/ApiExtractor/fileout.cpp b/sources/shiboken2/ApiExtractor/fileout.cpp
index 522c98fb5..475eb386b 100644
--- a/sources/shiboken2/ApiExtractor/fileout.cpp
+++ b/sources/shiboken2/ApiExtractor/fileout.cpp
@@ -27,6 +27,7 @@
 ****************************************************************************/
 
 #include "fileout.h"
+#include "messages.h"
 #include "reporthandler.h"
 
 #include <QtCore/QTextCodec>
@@ -178,18 +179,6 @@ FileOut::State FileOut::done()
     return result;
 }
 
-QString FileOut::msgCannotOpenForReading(const QFile &f)
-{
-    return QStringLiteral("Failed to open file '%1' for reading: %2")
-           .arg(QDir::toNativeSeparators(f.fileName()), f.errorString());
-}
-
-QString FileOut::msgCannotOpenForWriting(const QFile &f)
-{
-    return QStringLiteral("Failed to open file '%1' for writing: %2")
-           .arg(QDir::toNativeSeparators(f.fileName()), f.errorString());
-}
-
 FileOut::State FileOut::done(QString *errorMessage)
 {
     Q_ASSERT(!isDone);
diff --git a/sources/shiboken2/ApiExtractor/fileout.h b/sources/shiboken2/ApiExtractor/fileout.h
index ed995425d..6c27b5b00 100644
--- a/sources/shiboken2/ApiExtractor/fileout.h
+++ b/sources/shiboken2/ApiExtractor/fileout.h
@@ -49,9 +49,6 @@ public:
     State done();
     State done(QString *errorMessage);
 
-    static QString msgCannotOpenForReading(const QFile &f);
-    static QString msgCannotOpenForWriting(const QFile &f);
-
     QTextStream stream;
 
     static bool dummy;
diff --git a/sources/shiboken2/ApiExtractor/messages.cpp b/sources/shiboken2/ApiExtractor/messages.cpp
new file mode 100644
index 000000000..c4537ee39
--- /dev/null
+++ b/sources/shiboken2/ApiExtractor/messages.cpp
@@ -0,0 +1,435 @@
+/****************************************************************************
+**
+** Copyright (C) 2018 The Qt Company Ltd.
+** Contact: https://www.qt.io/licensing/
+**
+** This file is part of Qt for Python.
+**
+** $QT_BEGIN_LICENSE:GPL-EXCEPT$
+** 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.
+**
+** GNU General Public License Usage
+** Alternatively, this file may be used under the terms of the GNU
+** General Public License version 3 as published by the Free Software
+** Foundation with exceptions as appearing in the file LICENSE.GPL3-EXCEPT
+** included in the packaging of this file. Please review the following
+** information to ensure the GNU General Public License requirements will
+** be met: https://www.gnu.org/licenses/gpl-3.0.html.
+**
+** $QT_END_LICENSE$
+**
+****************************************************************************/
+
+#include "messages.h"
+#include "abstractmetalang.h"
+#include "typesystem.h"
+#include <codemodel.h>
+
+#include <QtCore/QCoreApplication>
+#include <QtCore/QDebug>
+#include <QtCore/QDir>
+#include <QtCore/QFile>
+#include <QtCore/QStringList>
+#include <QtCore/QXmlStreamReader>
+
+static inline QString colonColon() { return QStringLiteral("::"); }
+
+// abstractmetabuilder.cpp
+
+QString msgNoFunctionForModification(const QString &signature,
+                                     const QString &originalSignature,
+                                     const QString &className,
+                                     const QStringList &possibleSignatures,
+                                     const AbstractMetaFunctionList &allFunctions)
+{
+    QString result;
+    QTextStream str(&result);
+    str << "signature '" << signature << '\'';
+    if (!originalSignature.isEmpty() && originalSignature != signature)
+        str << " (specified as '" << originalSignature << "')";
+    str << " for function modification in '"
+        << className << "' not found.";
+    if (possibleSignatures.isEmpty()) {
+        str << " No candidates were found. Member functions: ";
+        for (int f = 0, size = allFunctions.size(); f < size; ++f) {
+            if (f)
+                str << ", ";
+            str << allFunctions.at(f)->minimalSignature();
+        }
+    } else {
+        str << " Possible candidates: " << possibleSignatures.join(QLatin1String(", "));
+    }
+    return result;
+}
+
+template <class Stream>
+static void msgFormatEnumType(Stream &str,
+                              const EnumModelItem &enumItem,
+                              const QString &className)
+{
+    switch (enumItem->enumKind()) {
+    case CEnum:
+        str << "Enum '" << enumItem->qualifiedName().join(colonColon()) << '\'';
+        break;
+    case AnonymousEnum: {
+        const EnumeratorList &values = enumItem->enumerators();
+        str << "Anonymous enum (";
+        switch (values.size()) {
+        case 0:
+            break;
+        case 1:
+            str << values.constFirst()->name();
+            break;
+        case 2:
+            str << values.at(0)->name() << ", " << values.at(1)->name();
+            break;
+        default:
+            str << values.at(0)->name() << ", ... , "
+                << values.at(values.size() - 1)->name();
+            break;
+        }
+        str << ')';
+    }
+        break;
+    case EnumClass:
+        str << "Scoped enum '" << enumItem->qualifiedName().join(colonColon()) << '\'';
+        break;
+    }
+    if (!className.isEmpty())
+        str << " (class: " << className << ')';
+}
+
+QString msgNoEnumTypeEntry(const EnumModelItem &enumItem,
+                           const QString &className)
+{
+    QString result;
+    QTextStream str(&result);
+    msgFormatEnumType(str, enumItem, className);
+    str << " does not have a type entry";
+    return result;
+}
+
+QString msgNoEnumTypeConflict(const EnumModelItem &enumItem,
+                              const QString &className,
+                              const TypeEntry *t)
+{
+    QString result;
+    QDebug debug(&result); // Use the debug operator for TypeEntry::Type
+    debug.noquote();
+    debug.nospace();
+    msgFormatEnumType(debug, enumItem, className);
+    debug << " is not an enum (type: " << t->type() << ')';
+    return result;
+}
+
+QString msgUnmatchedParameterType(const ArgumentModelItem &arg, int n,
+                                  const QString &why)
+{
+    QString result;
+    QTextStream str(&result);
+    str << "unmatched type '" << arg->type().toString() << "' in parameter #"
+        << (n + 1);
+    if (!arg->name().isEmpty())
+        str << " \"" << arg->name() << '"';
+    str << ": " << why;
+    return result;
+}
+
+QString msgUnmatchedReturnType(const FunctionModelItem &functionItem,
+                               const QString &why)
+{
+    return QLatin1String("unmatched return type '")
+        + functionItem->type().toString()
+        + QLatin1String("': ") + why;
+}
+
+QString msgSkippingFunction(const FunctionModelItem &functionItem,
+                            const QString &signature, const QString &why)
+{
+    QString result;
+    QTextStream str(&result);
+    str << "skipping ";
+    if (functionItem->isAbstract())
+        str << "abstract ";
+    str << "function '" << signature << "', " << why;
+    if (functionItem->isAbstract()) {
+        str << "\nThis will lead to compilation errors due to not "
+               "being able to instantiate the wrapper.";
+    }
+    return result;
+}
+
+QString msgCannotSetArrayUsage(const QString &function, int i, const QString &reason)
+{
+    return function +  QLatin1String(": Cannot use parameter ")
+        + QString::number(i + 1) + QLatin1String(" as an array: ") + reason;
+}
+
+QString msgUnableToTranslateType(const QString &t, const QString &why)
+{
+    return QLatin1String("Unable to translate type \"")
+        + t + QLatin1String("\": ") + why;
+}
+
+QString msgUnableToTranslateType(const TypeInfo &typeInfo,
+                                 const QString &why)
+{
+    return msgUnableToTranslateType(typeInfo.toString(), why);
+}
+
+QString msgCannotFindTypeEntry(const QString &t)
+{
+    return QLatin1String("Cannot find type entry for \"") + t + QLatin1String("\".");
+}
+
+QString msgCannotTranslateTemplateArgument(int i,
+                                           const TypeInfo &typeInfo,
+                                           const QString &why)
+{
+    QString result;
+    QTextStream(&result) << "Unable to translate template argument "
+        << (i + 1) << typeInfo.toString() << ": " << why;
+    return result;
+}
+
+// abstractmetalang.cpp
+
+QString msgDisallowThread(const AbstractMetaFunction *f)
+{
+    QString result;
+    QTextStream str(&result);
+    str <<"Disallowing threads for ";
+    if (auto c = f->declaringClass())
+        str << c->name() << "::";
+    str << f->name() << "().";
+    return result;
+}
+
+// docparser.cpp
+
+QString msgCannotFindDocumentation(const QString &fileName,
+                                   const char *what, const QString &name,
+                                   const QString &query)
+{
+    QString result;
+    QTextStream(&result) << "Cannot find documentation for " << what
+        << ' ' << name << " in:\n    " << QDir::toNativeSeparators(fileName)
+        << "\n  using query:\n    " << query;
+    return result;
+}
+
+QString msgCannotFindDocumentation(const QString &fileName,
+                                   const AbstractMetaClass *metaClass,
+                                   const AbstractMetaFunction *function,
+                                   const QString &query)
+{
+    const QString name = metaClass->name() + QLatin1String("::")
+        + function->minimalSignature();
+    return msgCannotFindDocumentation(fileName, "function", name, query);
+}
+
+QString msgCannotFindDocumentation(const QString &fileName,
+                                   const AbstractMetaClass *metaClass,
+                                   const AbstractMetaEnum *e,
+                                   const QString &query)
+{
+    return msgCannotFindDocumentation(fileName, "enum",
+                                      metaClass->name() + QLatin1String("::") + e->name(),
+                                      query);
+}
+
+QString msgCannotFindDocumentation(const QString &fileName,
+                                   const AbstractMetaClass *metaClass,
+                                   const AbstractMetaField *f,
+                                   const QString &query)
+{
+    return msgCannotFindDocumentation(fileName, "field",
+                                      metaClass->name() + QLatin1String("::") + f->name(),
+                                      query);
+}
+
+QString msgXpathDocModificationError(const DocModificationList& mods,
+                                     const QString &what)
+{
+    QString result;
+    QTextStream str(&result);
+    str << "Error when applying modifications (";
+    for (const DocModification &mod : mods) {
+        if (mod.mode() == TypeSystem::DocModificationXPathReplace) {
+            str << '"' << mod.xpath() << "\" -> \"";
+            const QString simplified = mod.code().simplified();
+            if (simplified.size() > 20)
+                str << simplified.leftRef(20) << "...";
+            else
+                str << simplified;
+            str << '"';
+        }
+    }
+    str << "): " << what;
+    return result;
+}
+
+// fileout.cpp
+
+QString msgCannotOpenForReading(const QFile &f)
+{
+    return QStringLiteral("Failed to open file '%1' for reading: %2")
+           .arg(QDir::toNativeSeparators(f.fileName()), f.errorString());
+}
+
+QString msgCannotOpenForWriting(const QFile &f)
+{
+    return QStringLiteral("Failed to open file '%1' for writing: %2")
+           .arg(QDir::toNativeSeparators(f.fileName()), f.errorString());
+}
+
+// main.cpp
+
+QString msgLeftOverArguments(const QMap<QString, QString> &remainingArgs)
+{
+    QString message;
+    QTextStream str(&message);
+    str << "shiboken: Called with wrong arguments:";
+    for (auto it = remainingArgs.cbegin(), end = remainingArgs.cend(); it != end; ++it) {
+        str << ' ' << it.key();
+        if (!it.value().isEmpty())
+            str << ' ' << it.value();
+    }
+    str << "\nCommand line: " << QCoreApplication::arguments().join(QLatin1Char(' '));
+    return message;
+}
+
+QString msgInvalidVersion(const QString &package, const QString &version)
+{
+    return QLatin1String("Invalid version \"") + version
+        + QLatin1String("\" specified for package ") + package + QLatin1Char('.');
+}
+
+QString msgCyclicDependency(const QString &funcName, const QString &graphName,
+                            const QVector<const AbstractMetaFunction *> &involvedConversions)
+{
+    QString result;
+    QTextStream str(&result);
+    str << "Cyclic dependency found on overloaddata for \"" << funcName
+         << "\" method! The graph boy saved the graph at \""
+         << QDir::toNativeSeparators(graphName) << "\".";
+    if (const int count = involvedConversions.size()) {
+        str << " Implicit conversions (" << count << "): ";
+        for (int i = 0; i < count; ++i) {
+            if (i)
+                str << ", \"";
+            str << involvedConversions.at(i)->signature() << '"';
+            if (const AbstractMetaClass *c = involvedConversions.at(i)->implementingClass())
+                str << '(' << c->name() << ')';
+        }
+    }
+    return result;
+}
+
+// shibokengenerator.cpp
+
+QString msgUnknownOperator(const AbstractMetaFunction* func)
+{
+    QString result = QLatin1String("Unknown operator: \"") + func->originalName()
+                     + QLatin1Char('"');
+    if (const AbstractMetaClass *c = func->implementingClass())
+        result += QLatin1String(" in class: ") + c->name();
+    return result;
+}
+
+QString msgWrongIndex(const char *varName, const QString &capture,
+                      const AbstractMetaFunction *func)
+{
+    QString result;
+    QTextStream str(&result);
+    str << "Wrong index for " << varName << " variable (" << capture << ") on ";
+    if (const AbstractMetaClass *c = func->implementingClass())
+        str << c->name() << "::";
+    str << func->signature();
+    return  result;
+}
+
+QString msgCannotFindType(const QString &type, const QString &variable,
+                          const QString &why)
+{
+    QString result;
+    QTextStream(&result) << "Could not find type '"
+        << type << "' for use in '" << variable << "' conversion: " << why
+        << "\nMake sure to use the full C++ name, e.g. 'Namespace::Class'.";
+    return result;
+}
+
+QString msgCannotBuildMetaType(const QString &s)
+{
+    return QLatin1String("Unable to build meta type for \"")
+        + s + QLatin1String("\": ");
+}
+
+QString msgCouldNotFindMinimalConstructor(const QString &where, const QString &type)
+{
+    return where + QLatin1String(": Could not find a minimal constructor for type '")
+       + type + QLatin1String("'. This will result in a compilation error.");
+}
+
+// typedatabase.cpp
+
+QString msgRejectReason(const TypeRejection &r, const QString &needle)
+{
+    QString result;
+    QTextStream str(&result);
+    switch (r.matchType) {
+    case TypeRejection::ExcludeClass:
+        str << " matches class exclusion \"" << r.className.pattern() << '"';
+        break;
+    case TypeRejection::Function:
+    case TypeRejection::Field:
+    case TypeRejection::Enum:
+        str << " matches class \"" << r.className.pattern() << "\" and \""
+            << r.pattern.pattern() << '"';
+        break;
+    case TypeRejection::ArgumentType:
+    case TypeRejection::ReturnType:
+        str << " matches class \"" << r.className.pattern() << "\" and \""
+            << needle << "\" matches \"" << r.pattern.pattern() << '"';
+        break;
+    case TypeRejection::Invalid:
+        break;
+    }
+    return result;
+}
+
+// qtdocgenerator.cpp
+
+QString msgTagWarning(const QXmlStreamReader &reader, const QString &context,
+                      const QString &tag, const QString &message)
+{
+    QString result;
+    QTextStream str(&result);
+    str << "While handling <";
+    const QStringRef currentTag = reader.name();
+    if (currentTag.isEmpty())
+        str << tag;
+    else
+        str << currentTag;
+    str << "> in " << context << ", line "<< reader.lineNumber()
+        << ": " << message;
+    return result;
+}
+
+QString msgFallbackWarning(const QXmlStreamReader &reader, const QString &context,
+                           const QString &tag, const QString &location,
+                           const QString &identifier, const QString &fallback)
+{
+    QString message = QLatin1String("Falling back to \"")
+        + QDir::toNativeSeparators(fallback) + QLatin1String("\" for \"")
+        + location + QLatin1Char('"');
+    if (!identifier.isEmpty())
+        message += QLatin1String(" [") + identifier + QLatin1Char(']');
+    return msgTagWarning(reader, context, tag, message);
+}
diff --git a/sources/shiboken2/ApiExtractor/messages.h b/sources/shiboken2/ApiExtractor/messages.h
new file mode 100644
index 000000000..cf6800b5d
--- /dev/null
+++ b/sources/shiboken2/ApiExtractor/messages.h
@@ -0,0 +1,140 @@
+/****************************************************************************
+**
+** Copyright (C) 2018 The Qt Company Ltd.
+** Contact: https://www.qt.io/licensing/
+**
+** This file is part of Qt for Python.
+**
+** $QT_BEGIN_LICENSE:GPL-EXCEPT$
+** 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.
+**
+** GNU General Public License Usage
+** Alternatively, this file may be used under the terms of the GNU
+** General Public License version 3 as published by the Free Software
+** Foundation with exceptions as appearing in the file LICENSE.GPL3-EXCEPT
+** included in the packaging of this file. Please review the following
+** information to ensure the GNU General Public License requirements will
+** be met: https://www.gnu.org/licenses/gpl-3.0.html.
+**
+** $QT_END_LICENSE$
+**
+****************************************************************************/
+
+#ifndef MESSAGES_H
+#define MESSAGES_H
+
+#include "abstractmetalang_typedefs.h"
+#include "parser/codemodel_fwd.h"
+#include "typesystem_typedefs.h"
+
+#include <QtCore/QMap>
+#include <QtCore/QString>
+#include <QtCore/QVector>
+
+class TypeEntry;
+class TypeInfo;
+struct TypeRejection;
+
+QT_FORWARD_DECLARE_CLASS(QDir)
+QT_FORWARD_DECLARE_CLASS(QFile)
+QT_FORWARD_DECLARE_CLASS(QXmlStreamReader)
+
+QString msgNoFunctionForModification(const QString &signature,
+                                     const QString &originalSignature,
+                                     const QString &className,
+                                     const QStringList &possibleSignatures,
+                                     const AbstractMetaFunctionList &allFunctions);
+
+QString msgNoEnumTypeEntry(const EnumModelItem &enumItem,
+                           const QString &className);
+
+
+QString msgNoEnumTypeConflict(const EnumModelItem &enumItem,
+                              const QString &className,
+                              const TypeEntry *t);
+
+QString msgUnmatchedParameterType(const ArgumentModelItem &arg, int n,
+                                  const QString &why);
+
+QString msgUnmatchedReturnType(const FunctionModelItem &functionItem,
+                               const QString &why);
+
+QString msgSkippingFunction(const FunctionModelItem &functionItem,
+                            const QString &signature, const QString &why);
+
+QString msgCannotSetArrayUsage(const QString &function, int i, const QString &reason);
+
+QString msgUnableToTranslateType(const QString &t, const QString &why);
+
+QString msgUnableToTranslateType(const TypeInfo &typeInfo,
+                                 const QString &why);
+
+QString msgCannotFindTypeEntry(const QString &t);
+
+QString msgCannotTranslateTemplateArgument(int i,
+                                           const TypeInfo &typeInfo,
+                                           const QString &why);
+
+QString msgDisallowThread(const AbstractMetaFunction *f);
+
+QString msgCannotFindDocumentation(const QString &fileName,
+                                   const char *what, const QString &name,
+                                   const QString &query);
+
+QString msgCannotFindDocumentation(const QString &fileName,
+                                   const AbstractMetaClass *metaClass,
+                                   const AbstractMetaFunction *function,
+                                   const QString &query);
+
+QString msgCannotFindDocumentation(const QString &fileName,
+                                   const AbstractMetaClass *metaClass,
+                                   const AbstractMetaEnum *e,
+                                   const QString &query);
+
+QString msgCannotFindDocumentation(const QString &fileName,
+                                   const AbstractMetaClass *metaClass,
+                                   const AbstractMetaField *f,
+                                   const QString &query);
+
+QString msgXpathDocModificationError(const DocModificationList& mods,
+                                     const QString &what);
+
+QString msgCannotOpenForReading(const QFile &f);
+
+QString msgCannotOpenForWriting(const QFile &f);
+
+QString msgLeftOverArguments(const QMap<QString, QString> &remainingArgs);
+
+QString msgInvalidVersion(const QString &package, const QString &version);
+
+QString msgCyclicDependency(const QString &funcName, const QString &graphName,
+                            const QVector<const AbstractMetaFunction *> &involvedConversions);
+
+QString msgUnknownOperator(const AbstractMetaFunction* func);
+
+QString msgWrongIndex(const char *varName, const QString &capture,
+                      const AbstractMetaFunction *func);
+
+QString msgCannotFindType(const QString &type, const QString &variable,
+                          const QString &why);
+
+QString msgCannotBuildMetaType(const QString &s);
+
+QString msgCouldNotFindMinimalConstructor(const QString &where, const QString &type);
+
+QString msgRejectReason(const TypeRejection &r, const QString &needle = QString());
+
+QString msgTagWarning(const QXmlStreamReader &reader, const QString &context,
+                      const QString &tag, const QString &message);
+
+QString msgFallbackWarning(const QXmlStreamReader &reader, const QString &context,
+                           const QString &tag, const QString &location,
+                           const QString &identifier, const QString &fallback);
+
+#endif // MESSAGES_H
diff --git a/sources/shiboken2/ApiExtractor/qtdocparser.cpp b/sources/shiboken2/ApiExtractor/qtdocparser.cpp
index b0058d6ea..809760450 100644
--- a/sources/shiboken2/ApiExtractor/qtdocparser.cpp
+++ b/sources/shiboken2/ApiExtractor/qtdocparser.cpp
@@ -28,6 +28,7 @@
 
 #include "qtdocparser.h"
 #include "abstractmetalang.h"
+#include "messages.h"
 #include "reporthandler.h"
 #include "typesystem.h"