Generator data: use a template method to reduce pattern duplication

Change-Id: I7613d221fba6d343726418837ce5f3013b9a8d96
Reviewed-by: Joerg Bornemann <joerg.bornemann@qt.io>

2 files changed, 36 insertions, 53 deletions

diff --git a/src/lib/corelib/generators/generatordata.cpp b/src/lib/corelib/generators/generatordata.cpp
index 1ff186580..37e4246fe 100644
--- a/src/lib/corelib/generators/generatordata.cpp
+++ b/src/lib/corelib/generators/generatordata.cpp
@@ -47,65 +47,30 @@ namespace qbs {
 
 QString GeneratableProductData::name() const
 {
-    QString name;
-    QMapIterator<QString, ProductData> it(data);
-    while (it.hasNext()) {
-        it.next();
-        QString oldName = name;
-        name = it.value().name();
-        if (!oldName.isEmpty() && oldName != name)
-            throw ErrorInfo(QLatin1String("Products with different names per-configuration "
-                                          "are not compatible with this generator. Consider "
-                                          "using the targetName property instead."));
-    }
-    return name;
+    return uniqueValue<QString>(&ProductData::name,
+        QLatin1String("Products with different names per configuration are not "
+                      "compatible with this generator. "
+                      "Consider using the targetName property instead."));
 }
 
 CodeLocation GeneratableProductData::location() const
 {
-    CodeLocation location;
-    QMapIterator<QString, ProductData> it(data);
-    while (it.hasNext()) {
-        it.next();
-        CodeLocation oldLocation = location;
-        location = it.value().location();
-        if (oldLocation.isValid() && oldLocation != location)
-            throw ErrorInfo(QLatin1String("Products with different code locations "
-                                          "per-configuration are not compatible with this "
-                                          "generator."));
-    }
-    return location;
+    return uniqueValue<CodeLocation>(&ProductData::location,
+        QLatin1String("GeneratableProductData::location: internal bug; this should not happen."));
 }
 
 QStringList GeneratableProductData::dependencies() const
 {
-    QStringList list;
-    QMapIterator<QString, ProductData> it(data);
-    while (it.hasNext()) {
-        it.next();
-        QStringList oldList = list;
-        list = it.value().dependencies();
-        if (!oldList.isEmpty() && oldList != list)
-            throw ErrorInfo(QLatin1String("Products with different dependency lists "
-                                          "per-configuration are not compatible with this "
-                                          "generator."));
-    }
-    return list;
+    return uniqueValue<QStringList>(&ProductData::dependencies,
+        QLatin1String("Products with different dependency lists per configuration are not "
+                      "compatible with this generator."));
 }
 
 QString GeneratableProjectData::name() const
 {
-    QString name;
-    QMapIterator<QString, ProjectData> it(data);
-    while (it.hasNext()) {
-        it.next();
-        QString oldName = name;
-        name = it.value().name();
-        if (!oldName.isEmpty() && oldName != name)
-            throw ErrorInfo(QLatin1String("Projects with different names per-configuration "
-                                          "are not compatible with this generator."));
-    }
-    return name;
+    return uniqueValue<QString>(&ProjectData::name,
+        QLatin1String("Projects with different names per configuration are not "
+                      "compatible with this generator."));
 }
 
 CodeLocation GeneratableProjectData::location() const
diff --git a/src/lib/corelib/generators/generatordata.h b/src/lib/corelib/generators/generatordata.h
index 47f4acb93..d8cf91c34 100644
--- a/src/lib/corelib/generators/generatordata.h
+++ b/src/lib/corelib/generators/generatordata.h
@@ -44,22 +44,41 @@
 #include <QtCore/qmap.h>
 #include <api/project.h>
 #include <api/projectdata.h>
+#include <tools/error.h>
 #include <tools/installoptions.h>
+#include <tools/set.h>
+#include <functional>
 
 namespace qbs {
 
 typedef QMap<QString, Project> GeneratableProjectMap;
-typedef QMap<QString, ProjectData> GeneratableProjectDataMap;
-typedef QMap<QString, ProductData> GeneratableProductDataMap;
 
-struct QBS_EXPORT GeneratableProductData {
-    GeneratableProductDataMap data;
+template <typename U> struct IMultiplexableContainer {
+    QMap<QString, U> data;
+
+    template <typename T> T uniqueValue(const std::function<T(const U &data)> &func,
+                                        const QString &errorMessage) const
+    {
+        auto it = data.begin(), end = data.end();
+        auto value = func(*it++);
+        for (; it != end; ++it) {
+            if (value != func(*it))
+                throw ErrorInfo(errorMessage);
+        }
+        return value;
+    }
+
+protected:
+    IMultiplexableContainer() { }
+};
+
+struct QBS_EXPORT GeneratableProductData : public IMultiplexableContainer<ProductData> {
     QString name() const;
     CodeLocation location() const;
     QStringList dependencies() const;
 };
 
-struct QBS_EXPORT GeneratableProjectData {
+struct QBS_EXPORT GeneratableProjectData : public IMultiplexableContainer<ProjectData> {
     struct Id {
     private:
         friend struct GeneratableProjectData;
@@ -70,7 +89,6 @@ struct QBS_EXPORT GeneratableProjectData {
         bool operator<(const Id &id) const { return value < id.value; }
     };
 
-    GeneratableProjectDataMap data;
     QList<GeneratableProjectData> subProjects;
     QList<GeneratableProductData> products;
     QString name() const;