Allow projects to be nested.

This is nice to have for grouping products and a requirement for aggregating existing projects into a bigger one. Change-Id: I3394642e95ea57dbc6bf1603cfed6902a5906e4c Reviewed-by: Joerg Bornemann <joerg.bornemann@digia.com>
author: Christian Kandeler <christian.kandeler@digia.com> 2013-06-06 10:06:30 +0200
committer: Joerg Bornemann <joerg.bornemann@digia.com> 2013-06-17 14:23:19 +0200
commit: ab60f6e4c489ace089785c002d75018ac6a31e30 (patch)
tree: 91053ec752d9aa56df8061ba5e62c13431804a6b /src
parent: d3877c67d060d454ac66fde7b6ad41a2bb50d808 (diff)
49 files changed, 874 insertions, 429 deletions
diff --git a/src/app/qbs/commandlinefrontend.cpp b/src/app/qbs/commandlinefrontend.cpp
index eab67ac44..f2175ab98 100644
--- a/src/app/qbs/commandlinefrontend.cpp
+++ b/src/app/qbs/commandlinefrontend.cpp
@@ -265,7 +265,7 @@ CommandLineFrontend::ProductMap CommandLineFrontend::productsToUse() const
     foreach (const Project &project, m_projects) {
         QList<ProductData> &productList = products[project];
         const ProjectData projectData = project.projectData();
-        foreach (const ProductData &product, projectData.products()) {
+        foreach (const ProductData &product, projectData.allProducts()) {
             if (useAll || m_parser.products().contains(product.name())) {
                 productList << product;
                 productNames << product.name();
diff --git a/src/app/qbs/status.cpp b/src/app/qbs/status.cpp
index c09190f5e..303ea485c 100644
--- a/src/app/qbs/status.cpp
+++ b/src/app/qbs/status.cpp
@@ -118,7 +118,7 @@ int printStatus(const ProjectData &project)
 
     QStringList untrackedFilesInProject = allFilesInProject(projectDirectory);
     QStringList missingFiles;
-    foreach (const ProductData &product, project.products()) {
+    foreach (const ProductData &product, project.allProducts()) {
         qbsInfo() << "\nProduct: " << product.name()
                   << " (" << product.location().fileName() << ":"
                   << product.location().line() << ")";
diff --git a/src/lib/api/internaljobs.cpp b/src/lib/api/internaljobs.cpp
index 946a87fa6..2f67243d3 100644
--- a/src/lib/api/internaljobs.cpp
+++ b/src/lib/api/internaljobs.cpp
@@ -119,7 +119,7 @@ void InternalJob::cancel()
     m_observer->cancel();
 }
 
-void InternalJob::storeBuildGraph(const ResolvedProjectConstPtr &project)
+void InternalJob::storeBuildGraph(const TopLevelProjectConstPtr &project)
 {
     try {
         project->store(logger());
@@ -154,7 +154,7 @@ void InternalSetupProjectJob::reportError(const Error &error)
                               Q_ARG(Internal::InternalJob *, this));
 }
 
-ResolvedProjectPtr InternalSetupProjectJob::project() const
+TopLevelProjectPtr InternalSetupProjectJob::project() const
 {
     return m_project;
 }
@@ -201,10 +201,6 @@ void InternalSetupProjectJob::execute()
             loader.setProgressObserver(observer());
             m_project = loader.loadProject(m_parameters);
         }
-        if (m_project->products.isEmpty()) {
-            throw Error(Tr::tr("Project '%1' does not contain products.")
-                        .arg(m_parameters.projectFilePath()));
-        }
     }
 
     // copy the environment from the platform config into the project's config
@@ -216,7 +212,7 @@ void InternalSetupProjectJob::execute()
     foreach (const ResolvedProductConstPtr &p, m_project->products) {
         logger().qbsDebug() << QString::fromLocal8Bit("  - [%1] %2 as %3")
                                .arg(p->fileTags.toStringList().join(QLatin1String(", ")))
-                               .arg(p->name).arg(p->project->id());
+                               .arg(p->name).arg(p->topLevelProject()->id());
     }
     logger().qbsDebug() << '\n';
 
@@ -244,7 +240,7 @@ BuildGraphTouchingJob::~BuildGraphTouchingJob()
 {
 }
 
-void BuildGraphTouchingJob::setup(const ResolvedProjectPtr &project,
+void BuildGraphTouchingJob::setup(const TopLevelProjectPtr &project,
                                   const QList<ResolvedProductPtr> &products, bool dryRun)
 {
     m_project = project;
@@ -263,7 +259,7 @@ InternalBuildJob::InternalBuildJob(const Logger &logger, QObject *parent)
 {
 }
 
-void InternalBuildJob::build(const ResolvedProjectPtr &project,
+void InternalBuildJob::build(const TopLevelProjectPtr &project,
         const QList<ResolvedProductPtr> &products, const BuildOptions &buildOptions)
 {
     setup(project, products, buildOptions.dryRun());
@@ -308,7 +304,7 @@ InternalCleanJob::InternalCleanJob(const Logger &logger, QObject *parent)
 {
 }
 
-void InternalCleanJob::clean(const ResolvedProjectPtr &project,
+void InternalCleanJob::clean(const TopLevelProjectPtr &project,
                              const QList<ResolvedProductPtr> &products, const CleanOptions &options)
 {
     setup(project, products, options.dryRun());
@@ -350,9 +346,10 @@ InternalInstallJob::~InternalInstallJob()
 {
 }
 
-void InternalInstallJob::install(const QList<ResolvedProductPtr> &products,
-                                 const InstallOptions &options)
+void InternalInstallJob::install(const TopLevelProjectPtr &project,
+        const QList<ResolvedProductPtr> &products, const InstallOptions &options)
 {
+    m_project = project;
     m_products = products;
     m_options = options;
     setTimed(options.logElapsedTime());
@@ -374,7 +371,7 @@ void InternalInstallJob::start()
 void InternalInstallJob::doInstall()
 {
     try {
-        ProductInstaller(m_products, m_options, observer(), logger()).install();
+        ProductInstaller(m_project, m_products, m_options, observer(), logger()).install();
     } catch (const Error &error) {
         setError(error);
     }
diff --git a/src/lib/api/internaljobs.h b/src/lib/api/internaljobs.h
index b94403fcb..37b2f607d 100644
--- a/src/lib/api/internaljobs.h
+++ b/src/lib/api/internaljobs.h
@@ -68,7 +68,7 @@ protected:
     JobObserver *observer() const { return m_observer; }
     void setError(const Error &error) { m_error = error; }
     void setTimed(bool timed) { m_timed = timed; }
-    void storeBuildGraph(const ResolvedProjectConstPtr &project);
+    void storeBuildGraph(const TopLevelProjectConstPtr &project);
 
 signals:
     void finished(Internal::InternalJob *job);
@@ -94,7 +94,7 @@ public:
     void resolve(const SetupProjectParameters &parameters);
     void reportError(const Error &error);
 
-    ResolvedProjectPtr project() const;
+    TopLevelProjectPtr project() const;
 
 private slots:
     void start();
@@ -108,7 +108,7 @@ private:
     QMutex m_runMutex;
     QWaitCondition m_runWaitCondition;
 
-    ResolvedProjectPtr m_project;
+    TopLevelProjectPtr m_project;
     SetupProjectParameters m_parameters;
 };
 
@@ -118,7 +118,7 @@ class BuildGraphTouchingJob : public InternalJob
     Q_OBJECT
 public:
     const QList<ResolvedProductPtr> &products() const { return m_products; }
-    const ResolvedProjectPtr &project() const { return m_project; }
+    const TopLevelProjectPtr &project() const { return m_project; }
 
 signals:
     void reportCommandDescription(const QString &highlight, const QString &message);
@@ -128,12 +128,12 @@ protected:
     BuildGraphTouchingJob(const Logger &logger, QObject *parent = 0);
     ~BuildGraphTouchingJob();
 
-    void setup(const ResolvedProjectPtr &project, const QList<ResolvedProductPtr> &products,
+    void setup(const TopLevelProjectPtr &project, const QList<ResolvedProductPtr> &products,
                bool dryRun);
     void storeBuildGraph();
 
 private:
-    ResolvedProjectPtr m_project;
+    TopLevelProjectPtr m_project;
     QList<ResolvedProductPtr> m_products;
     bool m_dryRun;
 };
@@ -145,7 +145,7 @@ class InternalBuildJob : public BuildGraphTouchingJob
 public:
     InternalBuildJob(const Logger &logger, QObject *parent = 0);
 
-    void build(const ResolvedProjectPtr &project, const QList<ResolvedProductPtr> &products,
+    void build(const TopLevelProjectPtr &project, const QList<ResolvedProductPtr> &products,
                const BuildOptions &buildOptions);
 
 private slots:
@@ -163,7 +163,7 @@ class InternalCleanJob : public BuildGraphTouchingJob
 public:
     InternalCleanJob(const Logger &logger, QObject *parent = 0);
 
-    void clean(const ResolvedProjectPtr &project, const QList<ResolvedProductPtr> &products,
+    void clean(const TopLevelProjectPtr &project, const QList<ResolvedProductPtr> &products,
                const CleanOptions &options);
 
 private slots:
@@ -185,7 +185,8 @@ public:
     InternalInstallJob(const Logger &logger, QObject *parent = 0);
     ~InternalInstallJob();
 
-    void install(const QList<ResolvedProductPtr> &products, const InstallOptions &options);
+    void install(const TopLevelProjectPtr &project, const QList<ResolvedProductPtr> &products,
+                 const InstallOptions &options);
 
 private slots:
     void handleFinished();
@@ -195,6 +196,7 @@ private:
     void doInstall();
 
 private:
+    TopLevelProjectPtr m_project;
     QList<ResolvedProductPtr> m_products;
     InstallOptions m_options;
 };
diff --git a/src/lib/api/jobs.cpp b/src/lib/api/jobs.cpp
index a344cc5c0..47bda7191 100644
--- a/src/lib/api/jobs.cpp
+++ b/src/lib/api/jobs.cpp
@@ -242,7 +242,7 @@ BuildJob::BuildJob(const Logger &logger, QObject *parent)
             this, SIGNAL(reportProcessResult(qbs::ProcessResult)));
 }
 
-void BuildJob::build(const ResolvedProjectPtr &project, const QList<ResolvedProductPtr> &products,
+void BuildJob::build(const TopLevelProjectPtr &project, const QList<ResolvedProductPtr> &products,
                      const BuildOptions &options)
 {
     qobject_cast<InternalBuildJob *>(internalJob())->build(project, products, options);
@@ -259,7 +259,7 @@ CleanJob::CleanJob(const Logger &logger, QObject *parent)
 {
 }
 
-void CleanJob::clean(const ResolvedProjectPtr &project, const QList<ResolvedProductPtr> &products,
+void CleanJob::clean(const TopLevelProjectPtr &project, const QList<ResolvedProductPtr> &products,
                      const qbs::CleanOptions &options)
 {
     qobject_cast<InternalCleanJob *>(internalJob())->clean(project, products, options);
@@ -275,9 +275,10 @@ InstallJob::InstallJob(const Logger &logger, QObject *parent)
 {
 }
 
-void InstallJob::install(const QList<ResolvedProductPtr> &products, const InstallOptions &options)
+void InstallJob::install(const TopLevelProjectPtr &project,
+                         const QList<ResolvedProductPtr> &products, const InstallOptions &options)
 {
-    qobject_cast<InternalInstallJob *>(internalJob())->install(products, options);
+    qobject_cast<InternalInstallJob *>(internalJob())->install(project, products, options);
 }
 
 } // namespace qbs
diff --git a/src/lib/api/jobs.h b/src/lib/api/jobs.h
index 19d4f8dcb..791ad2af7 100644
--- a/src/lib/api/jobs.h
+++ b/src/lib/api/jobs.h
@@ -113,7 +113,7 @@ signals:
 private:
     BuildJob(const Internal::Logger &logger, QObject *parent);
 
-    void build(const Internal::ResolvedProjectPtr &project,
+    void build(const Internal::TopLevelProjectPtr &project,
                const QList<qbs::Internal::ResolvedProductPtr> &products,
                const BuildOptions &options);
 };
@@ -127,7 +127,7 @@ class QBS_EXPORT CleanJob : public AbstractJob
 private:
     CleanJob(const Internal::Logger &logger, QObject *parent);
 
-    void clean(const Internal::ResolvedProjectPtr &project,
+    void clean(const Internal::TopLevelProjectPtr &project,
                const QList<Internal::ResolvedProductPtr> &products, const CleanOptions &options);
 };
 
@@ -138,8 +138,8 @@ class QBS_EXPORT InstallJob : public AbstractJob
 private:
     InstallJob(const Internal::Logger &logger, QObject *parent);
 
-    void install(const QList<Internal::ResolvedProductPtr> &products,
-                 const InstallOptions &options);
+    void install(const Internal::TopLevelProjectPtr &project,
+                 const QList<Internal::ResolvedProductPtr> &products, const InstallOptions &options);
 };
 
 } // namespace qbs
diff --git a/src/lib/api/project.cpp b/src/lib/api/project.cpp
index f9744d648..dca2104d8 100644
--- a/src/lib/api/project.cpp
+++ b/src/lib/api/project.cpp
@@ -91,7 +91,7 @@ static void loadPlugins(const QStringList &_pluginPaths, const Logger &logger)
 class ProjectPrivate : public QSharedData
 {
 public:
-    ProjectPrivate(const ResolvedProjectPtr &internalProject, const Logger &logger)
+    ProjectPrivate(const TopLevelProjectPtr &internalProject, const Logger &logger)
         : internalProject(internalProject), logger(logger), m_projectDataRetrieved(false)
     {
     }
@@ -109,11 +109,12 @@ public:
     QList<ResolvedProductPtr> allEnabledInternalProducts() const;
     ResolvedProductPtr internalProduct(const ProductData &product) const;
 
-    const ResolvedProjectPtr internalProject;
+    const TopLevelProjectPtr internalProject;
     Logger logger;
 
 private:
-    void retrieveProjectData();
+    void retrieveProjectData(ProjectData &projectData,
+                             const ResolvedProjectConstPtr &internalProject);
 
     ProjectData m_projectData;
     bool m_projectDataRetrieved;
@@ -121,8 +122,11 @@ private:
 
 ProjectData ProjectPrivate::projectData()
 {
-    if (!m_projectDataRetrieved)
-        retrieveProjectData();
+    if (!m_projectDataRetrieved) {
+        retrieveProjectData(m_projectData, internalProject);
+        m_projectData.d->buildDir = internalProject->buildDirectory;
+        m_projectDataRetrieved = true;
+    }
     return m_projectData;
 }
 
@@ -165,7 +169,7 @@ InstallJob *ProjectPrivate::installProducts(const QList<ResolvedProductPtr> &pro
     if (needsDepencencyResolving)
         addDependencies(productsToInstall);
     InstallJob * const job = new InstallJob(logger, jobOwner);
-    job->install(productsToInstall, options);
+    job->install(internalProject, productsToInstall, options);
     return job;
 }
 
@@ -179,30 +183,49 @@ QList<ResolvedProductPtr> ProjectPrivate::internalProducts(const QList<ProductDa
     return internalProducts;
 }
 
-QList<ResolvedProductPtr> ProjectPrivate::allEnabledInternalProducts() const
+static QList<ResolvedProductPtr> enabledInternalProducts(const ResolvedProjectConstPtr &project)
 {
     QList<ResolvedProductPtr> products;
-    foreach (const ResolvedProductPtr &p, internalProject->products) {
+    foreach (const ResolvedProductPtr &p, project->products) {
         if (p->enabled)
             products << p;
     }
+    foreach (const ResolvedProjectConstPtr &subProject, project->subProjects)
+        products << enabledInternalProducts(subProject);
     return products;
 }
 
-ResolvedProductPtr ProjectPrivate::internalProduct(const ProductData &product) const
+QList<ResolvedProductPtr> ProjectPrivate::allEnabledInternalProducts() const
+{
+    return enabledInternalProducts(internalProject);
+}
+
+static ResolvedProductPtr internalProductForProject(const ResolvedProjectConstPtr &project,
+                                                    const ProductData &product)
 {
-    foreach (const ResolvedProductPtr &resolvedProduct, internalProject->products) {
+    foreach (const ResolvedProductPtr &resolvedProduct, project->products) {
         if (product.name() == resolvedProduct->name)
             return resolvedProduct;
     }
-    qFatal("No build product '%s'", qPrintable(product.name()));
+    foreach (const ResolvedProjectConstPtr &subProject, project->subProjects) {
+        const ResolvedProductPtr &p = internalProductForProject(subProject, product);
+        if (p)
+            return p;
+    }
     return ResolvedProductPtr();
 }
 
-void ProjectPrivate::retrieveProjectData()
+ResolvedProductPtr ProjectPrivate::internalProduct(const ProductData &product) const
+{
+    return internalProductForProject(internalProject, product);
+}
+
+void ProjectPrivate::retrieveProjectData(ProjectData &projectData,
+                                         const ResolvedProjectConstPtr &internalProject)
 {
-    m_projectData.d->location = internalProject->location;
-    m_projectData.d->buildDir = internalProject->buildDirectory;
+    projectData.d->name = internalProject->name;
+    projectData.d->location = internalProject->location;
+    projectData.d->enabled = internalProject->enabled;
     foreach (const ResolvedProductConstPtr &resolvedProduct, internalProject->products) {
         ProductData product;
         product.d->name = resolvedProduct->name;
@@ -227,9 +250,15 @@ void ProjectPrivate::retrieveProjectData()
             product.d->groups << group;
         }
         qSort(product.d->groups);
-        m_projectData.d->products << product;
+        projectData.d->products << product;
+    }
+    foreach (const ResolvedProjectConstPtr &internalSubProject, internalProject->subProjects) {
+        ProjectData subProject;
+        retrieveProjectData(subProject, internalSubProject);
+        projectData.d->subProjects << subProject;
     }
-    qSort(m_projectData.d->products);
+    qSort(projectData.d->products);
+    qSort(projectData.d->subProjects);
     m_projectDataRetrieved = true;
 }
 
@@ -242,7 +271,7 @@ using namespace Internal;
   * \brief The \c Project class provides services related to a qbs project.
   */
 
-Project::Project(const ResolvedProjectPtr &internalProject, const Logger &logger)
+Project::Project(const TopLevelProjectPtr &internalProject, const Logger &logger)
     : d(new ProjectPrivate(internalProject, logger))
 {
 }
diff --git a/src/lib/api/project.h b/src/lib/api/project.h
index 099b82d9a..48c3fd71b 100644
--- a/src/lib/api/project.h
+++ b/src/lib/api/project.h
@@ -107,7 +107,7 @@ public:
 
 private:
     Project();
-    Project(const Internal::ResolvedProjectPtr &internalProject, const Internal::Logger &logger);
+    Project(const Internal::TopLevelProjectPtr &internalProject, const Internal::Logger &logger);
 
     QExplicitlySharedDataPointer<Internal::ProjectPrivate> d;
 };
diff --git a/src/lib/api/projectdata.cpp b/src/lib/api/projectdata.cpp
index 7b46f1829..9d48f5f2f 100644
--- a/src/lib/api/projectdata.cpp
+++ b/src/lib/api/projectdata.cpp
@@ -130,6 +130,11 @@ QStringList GroupData::allFilePaths() const
     return d->filePaths + d->expandedWildcards;
 }
 
+bool operator!=(const GroupData &lhs, const GroupData &rhs)
+{
+    return !(lhs == rhs);
+}
+
 bool operator==(const GroupData &lhs, const GroupData &rhs)
 {
     return lhs.name() == rhs.name()
@@ -140,9 +145,9 @@ bool operator==(const GroupData &lhs, const GroupData &rhs)
             && lhs.isEnabled() == rhs.isEnabled();
 }
 
-bool operator!=(const GroupData &lhs, const GroupData &rhs)
+bool operator<(const GroupData &lhs, const GroupData &rhs)
 {
-    return !(lhs == rhs);
+    return lhs.name() < rhs.name();
 }
 
 /*!
@@ -237,7 +242,7 @@ bool operator!=(const ProductData &lhs, const ProductData &rhs)
     return !(lhs == rhs);
 }
 
-bool operator<(const GroupData &lhs, const GroupData &rhs)
+bool operator<(const ProductData &lhs, const ProductData &rhs)
 {
     return lhs.name() < rhs.name();
 }
@@ -271,6 +276,14 @@ ProjectData::~ProjectData()
 }
 
 /*!
+ * \brief The name of this project.
+ */
+QString ProjectData::name() const
+{
+    return d->name;
+}
+
+/*!
  * \brief The location at which the project is defined in a qbs source file.
  */
 CodeLocation ProjectData::location() const
@@ -279,7 +292,17 @@ CodeLocation ProjectData::location() const
 }
 
 /*!
+ * \brief Whether the project is enabled.
+ * \note Disabled projects never have any products or sub-projects.
+ */
+bool ProjectData::isEnabled() const
+{
+    return d->enabled;
+}
+
+/*!
  * \brief The base directory under which the build artifacts of this project will be created.
+ * This is only valid for the top-level project.
  */
 QString ProjectData::buildDirectory() const
 {
@@ -295,9 +318,29 @@ QList<ProductData> ProjectData::products() const
     return d->products;
 }
 
+/*!
+ * The sub-projects of this project.
+ */
+QList<ProjectData> ProjectData::subProjects() const
+{
+    return d->subProjects;
+}
+
+/*!
+ * All products in this projects and its direct and indirect sub-projects.
+ */
+QList<ProductData> ProjectData::allProducts() const
+{
+    QList<ProductData> productList = products();
+    foreach (const ProjectData &pd, subProjects())
+        productList << pd.allProducts();
+    return productList;
+}
+
 bool operator==(const ProjectData &lhs, const ProjectData &rhs)
 {
     return lhs.location() == rhs.location()
+            && lhs.subProjects() == rhs.subProjects()
             && lhs.products() == rhs.products();
 }
 
@@ -306,7 +349,7 @@ bool operator!=(const ProjectData &lhs, const ProjectData &rhs)
     return !(lhs == rhs);
 }
 
-bool operator<(const ProductData &lhs, const ProductData &rhs)
+bool operator<(const ProjectData &lhs, const ProjectData &rhs)
 {
     return lhs.name() < rhs.name();
 }
diff --git a/src/lib/api/projectdata.h b/src/lib/api/projectdata.h
index 1097c5e24..d7ae66b8f 100644
--- a/src/lib/api/projectdata.h
+++ b/src/lib/api/projectdata.h
@@ -139,9 +139,13 @@ public:
     ProjectData &operator=(const ProjectData &other);
     ~ProjectData();
 
+    QString name() const;
     CodeLocation location() const;
+    bool isEnabled() const;
     QString buildDirectory() const;
     QList<ProductData> products() const;
+    QList<ProjectData> subProjects() const;
+    QList<ProductData> allProducts() const;
 
 private:
     QExplicitlySharedDataPointer<Internal::ProjectDataPrivate> d;
@@ -149,6 +153,7 @@ private:
 
 QBS_EXPORT bool operator==(const ProjectData &lhs, const ProjectData &rhs);
 QBS_EXPORT bool operator!=(const ProjectData &lhs, const ProjectData &rhs);
+QBS_EXPORT bool operator<(const ProjectData &lhs, const ProjectData &rhs);
 
 } // namespace qbs
 
diff --git a/src/lib/api/projectdata_p.h b/src/lib/api/projectdata_p.h
index c544dd9d9..14ed79efd 100644
--- a/src/lib/api/projectdata_p.h
+++ b/src/lib/api/projectdata_p.h
@@ -61,8 +61,11 @@ public:
 class ProjectDataPrivate : public QSharedData
 {
 public:
+    QString name;
     CodeLocation location;
+    bool enabled;
     QList<ProductData> products;
+    QList<ProjectData> subProjects;
     QString buildDir;
 };
 
diff --git a/src/lib/buildgraph/artifact.cpp b/src/lib/buildgraph/artifact.cpp
index e2de97d75..60f62f768 100644
--- a/src/lib/buildgraph/artifact.cpp
+++ b/src/lib/buildgraph/artifact.cpp
@@ -143,5 +143,10 @@ void Artifact::disconnectAll(const Logger &logger)
     disconnectParents(logger);
 }
 
+TopLevelProject *Artifact::topLevelProject() const
+{
+    return project->topLevelProject();
+}
+
 } // namespace Internal
 } // namespace qbs
diff --git a/src/lib/buildgraph/artifact.h b/src/lib/buildgraph/artifact.h
index 03e6a9071..88d9b677f 100644
--- a/src/lib/buildgraph/artifact.h
+++ b/src/lib/buildgraph/artifact.h
@@ -102,6 +102,7 @@ public:
     QString dirPath() const { return m_dirPath.toString(); }
     QString fileName() const { return m_fileName.toString(); }
     void disconnectAll(const Logger &logger);
+    TopLevelProject *topLevelProject() const;
 
 private:
     void load(PersistentPool &pool);
diff --git a/src/lib/buildgraph/artifactcleaner.cpp b/src/lib/buildgraph/artifactcleaner.cpp
index a7695b3fb..5fc5deace 100644
--- a/src/lib/buildgraph/artifactcleaner.cpp
+++ b/src/lib/buildgraph/artifactcleaner.cpp
@@ -61,7 +61,7 @@ static void invalidateArtifactTimestamp(Artifact *artifact)
 {
     if (artifact->timestamp.isValid()) {
         artifact->timestamp.clear();
-        artifact->project->buildData->isDirty = true;
+        artifact->topLevelProject()->buildData->isDirty = true;
     }
 }
 
@@ -134,7 +134,7 @@ ArtifactCleaner::ArtifactCleaner(const Logger &logger, ProgressObserver *observe
 {
 }
 
-void ArtifactCleaner::cleanup(const ResolvedProjectPtr &project,
+void ArtifactCleaner::cleanup(const TopLevelProjectPtr &project,
         const QList<ResolvedProductPtr> &products, const CleanOptions &options)
 {
     m_hasError = false;
diff --git a/src/lib/buildgraph/artifactcleaner.h b/src/lib/buildgraph/artifactcleaner.h
index 5de78701c..516effb95 100644
--- a/src/lib/buildgraph/artifactcleaner.h
+++ b/src/lib/buildgraph/artifactcleaner.h
@@ -44,7 +44,7 @@ class ArtifactCleaner
 {
 public:
     ArtifactCleaner(const Logger &logger, ProgressObserver *observer);
-    void cleanup(const ResolvedProjectPtr &project, const QList<ResolvedProductPtr> &products,
+    void cleanup(const TopLevelProjectPtr &project, const QList<ResolvedProductPtr> &products,
                  const CleanOptions &options);
 
 private:
diff --git a/src/lib/buildgraph/artifactvisitor.cpp b/src/lib/buildgraph/artifactvisitor.cpp
index 7746ded85..24829c51e 100644
--- a/src/lib/buildgraph/artifactvisitor.cpp
+++ b/src/lib/buildgraph/artifactvisitor.cpp
@@ -66,6 +66,8 @@ void ArtifactVisitor::visitProject(const ResolvedProjectConstPtr &project)
 {
     foreach (const ResolvedProductConstPtr &product, project->products)
         visitProduct(product);
+    foreach (const ResolvedProjectConstPtr &subProject, project->subProjects)
+        visitProject(subProject);
 }
 
 } // namespace Internal
diff --git a/src/lib/buildgraph/automoc.cpp b/src/lib/buildgraph/automoc.cpp
index bf97caf50..1ff61c993 100644
--- a/src/lib/buildgraph/automoc.cpp
+++ b/src/lib/buildgraph/automoc.cpp
@@ -173,7 +173,7 @@ void AutoMoc::apply(const ResolvedProductPtr &product)
             loggedConnect(outputOfHeader, pluginMetaDataFile, m_logger);
     }
 
-    product->project->buildData->updateNodesThatMustGetNewTransformer(m_logger);
+    product->topLevelProject()->buildData->updateNodesThatMustGetNewTransformer(m_logger);
 }
 
 QString AutoMoc::generateMocFileName(Artifact *artifact, FileType fileType)
@@ -344,7 +344,7 @@ void AutoMoc::unmoc(Artifact *artifact, const FileTag &mocFileTag)
                 m_logger.qbsTrace() << "[AUTOMOC] removing moc obj artifact "
                                     << relativeArtifactFileName(mocObjArtifact);
             }
-            artifact->project->buildData->removeArtifact(mocObjArtifact, m_logger);
+            artifact->topLevelProject()->buildData->removeArtifact(mocObjArtifact, m_logger);
         }
     }
 
@@ -352,7 +352,7 @@ void AutoMoc::unmoc(Artifact *artifact, const FileTag &mocFileTag)
         m_logger.qbsTrace() << "[AUTOMOC] removing generated artifact "
                             << relativeArtifactFileName(generatedMocArtifact);
     }
-    artifact->project->buildData->removeArtifact(generatedMocArtifact, m_logger);
+    artifact->topLevelProject()->buildData->removeArtifact(generatedMocArtifact, m_logger);
     delete generatedMocArtifact;
 }
 
diff --git a/src/lib/buildgraph/buildgraph.cpp b/src/lib/buildgraph/buildgraph.cpp
index 91da59941..c9e8c0af4 100644
--- a/src/lib/buildgraph/buildgraph.cpp
+++ b/src/lib/buildgraph/buildgraph.cpp
@@ -255,7 +255,7 @@ void connect(Artifact *p, Artifact *c)
     QBS_CHECK(p != c);
     p->children.insert(c);
     c->parents.insert(p);
-    p->project->buildData->isDirty = true;
+    p->topLevelProject()->buildData->isDirty = true;
 }
 
 void loggedConnect(Artifact *u, Artifact *v, const Logger &logger)
@@ -327,7 +327,7 @@ void removeGeneratedArtifactFromDisk(Artifact *artifact, const Logger &logger)
 
 QString relativeArtifactFileName(const Artifact *n)
 {
-    const QString &buildDir = n->project->buildDirectory;
+    const QString &buildDir = n->topLevelProject()->buildDirectory;
     QString str = n->filePath();
     if (str.startsWith(buildDir))
         str.remove(0, buildDir.count());
@@ -340,7 +340,7 @@ Artifact *lookupArtifact(const ResolvedProductConstPtr &product, const QString &
                          const QString &fileName)
 {
     QList<Artifact *> artifacts
-            = product->project->buildData->lookupArtifacts(dirPath, fileName);
+            = product->topLevelProject()->buildData->lookupArtifacts(dirPath, fileName);
     for (QList<Artifact *>::const_iterator it = artifacts.constBegin();
          it != artifacts.constEnd(); ++it) {
         if ((*it)->product == product)
@@ -396,8 +396,8 @@ void insertArtifact(const ResolvedProductPtr &product, Artifact *artifact, const
 #endif
     product->buildData->artifacts.insert(artifact);
     artifact->product = product;
-    product->project->buildData->insertIntoArtifactLookupTable(artifact);
-    product->project->buildData->isDirty = true;
+    product->topLevelProject()->buildData->insertIntoArtifactLookupTable(artifact);
+    product->topLevelProject()->buildData->isDirty = true;
 
     if (logger.traceEnabled()) {
         logger.qbsTrace() << QString::fromLocal8Bit("[BG] insert artifact '%1'")
@@ -459,15 +459,33 @@ static bool isConfigCompatible(const QVariantMap &userCfg, const QVariantMap &pr
     return true;
 }
 
+void restoreBackPointers(const ResolvedProjectPtr &project)
+{
+    foreach (const ResolvedProductPtr &product, project->products) {
+        product->project = project;
+        if (!product->buildData)
+            continue;
+        foreach (Artifact * const a, product->buildData->artifacts) {
+            a->project = project;
+            project->topLevelProject()->buildData->insertIntoArtifactLookupTable(a);
+        }
+    }
+
+    foreach (const ResolvedProjectPtr &subProject, project->subProjects) {
+        subProject->parentProject = project;
+        restoreBackPointers(subProject);
+    }
+}
+
 BuildGraphLoader::LoadResult BuildGraphLoader::load(const SetupProjectParameters &parameters,
         const RulesEvaluationContextPtr &evalContext)
 {
     m_result = LoadResult();
     m_evalContext = evalContext;
 
-    const QString projectId = ResolvedProject::deriveId(parameters.buildConfiguration());
+    const QString projectId = TopLevelProject::deriveId(parameters.buildConfiguration());
     const QString buildDir
-            = ResolvedProject::deriveBuildDirectory(parameters.buildRoot(), projectId);
+            = TopLevelProject::deriveBuildDirectory(parameters.buildRoot(), projectId);
     const QString buildGraphFilePath
             = ProjectBuildData::deriveBuildGraphFilePath(buildDir, projectId);
 
@@ -481,23 +499,13 @@ BuildGraphLoader::LoadResult BuildGraphLoader::load(const SetupProjectParameters
         return m_result;
     }
 
-    const ResolvedProjectPtr project = ResolvedProject::create();
+    const TopLevelProjectPtr project = TopLevelProject::create();
 
     // TODO: Store some meta data that will enable us to show actual progress (e.g. number of products).
     evalContext->initializeObserver(Tr::tr("Restoring build graph from disk"), 1);
 
     project->load(pool);
     project->buildData->evaluationContext = evalContext;
-    foreach (Artifact * const a, project->buildData->dependencyArtifacts)
-        a->project = project;
-    foreach (const ResolvedProductPtr &product, project->products) {
-        if (!product->buildData)
-            continue;
-        foreach (Artifact * const a, product->buildData->artifacts) {
-            a->project = project;
-            project->buildData->insertIntoArtifactLookupTable(a);
-        }
-    }
 
     if (QFileInfo(project->location.fileName()) != QFileInfo(parameters.projectFilePath())) {
         QString errorMessage = Tr::tr("Stored build graph is for project file '%1', but "
@@ -513,9 +521,13 @@ BuildGraphLoader::LoadResult BuildGraphLoader::load(const SetupProjectParameters
         errorMessage += Tr::tr("Ignoring.");
         m_logger.qbsWarning() << errorMessage;
     }
-    foreach (const ResolvedProductPtr &p, project->products)
-        p->project = project;
-    project->location = CodeLocation(parameters.projectFilePath(), 1, 1);
+
+    restoreBackPointers(project);
+    foreach (Artifact * const a, project->buildData->dependencyArtifacts)
+        a->project = project;
+
+    project->location = CodeLocation(parameters.projectFilePath(), project->location.line(),
+                                     project->location.column());
     project->setBuildConfiguration(pool.headData().projectConfig);
     project->buildDirectory = buildDir;
     m_result.loadedProject = project;
@@ -524,14 +536,77 @@ BuildGraphLoader::LoadResult BuildGraphLoader::load(const SetupProjectParameters
     return m_result;
 }
 
+static void exchangeDependencies(const ResolvedProductPtr &newProduct,
+                                 const QList<ResolvedProductPtr> &allRestoredProducts,
+                                 const QList<ResolvedProductPtr> &addedProducts)
+{
+    QSet<ResolvedProductPtr> newDependencies;
+    foreach (const ResolvedProductPtr &dependency, newProduct->dependencies) {
+        if (addedProducts.contains(dependency)) {
+            newDependencies << dependency;
+            exchangeDependencies(dependency, allRestoredProducts, addedProducts);
+            continue;
+        }
+        bool counterPartFound = false;
+        foreach (const ResolvedProductPtr &restoredProduct, allRestoredProducts) {
+            if (restoredProduct->name == dependency->name) {
+                newDependencies << restoredProduct;
+                counterPartFound = true;
+                break;
+            }
+        }
+        QBS_CHECK(counterPartFound);
+    }
+    newProduct->dependencies = newDependencies;
+}
+
+static void manipulateAddedProducts(const QList<ResolvedProjectPtr> &allRestoredProjects,
+                                    const QList<ResolvedProductPtr> &allRestoredProducts,
+                                    const QList<ResolvedProductPtr> &addedProducts)
+{
+    foreach (const ResolvedProductPtr &product, addedProducts) {
+        // Find the right existing (sub-)project to put the new product into.
+        bool projectFound = false;
+        foreach (const ResolvedProjectPtr &project, allRestoredProjects) {
+            if (project->location != product->project->location)
+                continue;
+            product->project = project;
+            project->products.append(product);
+            projectFound = true;
+            break;
+        }
+        QBS_CHECK(projectFound);
+
+        // Exchange dependencies that are not new with their counterparts from the restored project.
+        exchangeDependencies(product, allRestoredProducts, addedProducts);
+    }
+}
+
+// TODO: Pay more attention to project metadata such as name and location. If these change,
+// we must transfer them over to the old build graph.
 void BuildGraphLoader::trackProjectChanges(const SetupProjectParameters &parameters,
-        const QString &buildGraphFilePath, const ResolvedProjectPtr &restoredProject)
+        const QString &buildGraphFilePath, const TopLevelProjectPtr &restoredProject)
 {
     const FileInfo bgfi(buildGraphFilePath);
-    const bool projectFileChanged
-            = bgfi.lastModified() < FileInfo(parameters.projectFilePath()).lastModified();
+    const QList<ResolvedProjectPtr> allRestoredProjects
+            = restoredProject->allSubProjects() << restoredProject;
+    bool projectFileChanged = false;
+    bool subProjectRemoved = false;
+    foreach (const ResolvedProjectConstPtr &p, allRestoredProjects) {
+        FileInfo fi(p->location.fileName());
+        if (!fi.exists()) {
+            subProjectRemoved = true;
+            break;
+        }
+        if (bgfi.lastModified() < fi.lastModified()) {
+            projectFileChanged = true;
+            break;
+        }
+    }
+    if (subProjectRemoved)
+        m_logger.qbsTrace() << "A sub-project was removed, must re-resolve project";
     if (projectFileChanged)
-        m_logger.qbsTrace() << "Project file changed, must re-resolve project.";
+        m_logger.qbsTrace() << "A project file changed, must re-resolve project.";
 
     bool environmentChanged = false;
     for (QHash<QString, QString>::ConstIterator it = restoredProject->usedEnvironment.constBegin();
@@ -541,12 +616,13 @@ void BuildGraphLoader::trackProjectChanges(const SetupProjectParameters &paramet
     if (environmentChanged)
         m_logger.qbsTrace() << "A relevant environment variable changed, must re-resolve project.";
 
-    bool referencedProductRemoved = false;
+    bool productRemoved = false;
+    const QList<ResolvedProductPtr> allRestoredProducts = restoredProject->allProducts();
     QList<ResolvedProductPtr> changedProducts;
-    foreach (const ResolvedProductPtr &product, restoredProject->products) {
+    foreach (const ResolvedProductPtr &product, allRestoredProducts) {
         const FileInfo pfi(product->location.fileName());
         if (!pfi.exists()) {
-            referencedProductRemoved = true;
+            productRemoved = true;
         } else if (bgfi.lastModified() < pfi.lastModified()) {
             changedProducts += product;
         } else {
@@ -566,7 +642,7 @@ void BuildGraphLoader::trackProjectChanges(const SetupProjectParameters &paramet
         }
     }
 
-    if (!environmentChanged && !projectFileChanged && !referencedProductRemoved
+    if (!environmentChanged && !projectFileChanged && !subProjectRemoved && !productRemoved
             && changedProducts.isEmpty()) {
         return;
     }
@@ -576,11 +652,13 @@ void BuildGraphLoader::trackProjectChanges(const SetupProjectParameters &paramet
     m_result.newlyResolvedProject = ldr.loadProject(parameters);
 
     QMap<QString, ResolvedProductPtr> freshProductsByName;
-    foreach (const ResolvedProductPtr &cp, m_result.newlyResolvedProject->products)
+    const QList<ResolvedProductPtr> allNewlyResolvedProducts
+            = m_result.newlyResolvedProject->allProducts();
+    foreach (const ResolvedProductPtr &cp, allNewlyResolvedProducts)
         freshProductsByName.insert(cp->name, cp);
 
     QSet<TransformerPtr> seenTransformers;
-    foreach (const ResolvedProductPtr &product, restoredProject->products) {
+    foreach (const ResolvedProductPtr &product, allRestoredProducts) {
         if (!product->buildData)
             continue;
         foreach (Artifact *artifact, product->buildData->artifacts) {
@@ -605,14 +683,14 @@ void BuildGraphLoader::trackProjectChanges(const SetupProjectParameters &paramet
     }
 
     QSet<QString> oldProductNames, newProductNames;
-    foreach (const ResolvedProductConstPtr &product, restoredProject->products)
+    foreach (const ResolvedProductConstPtr &product, allRestoredProducts)
         oldProductNames += product->name;
-    foreach (const ResolvedProductConstPtr &product, m_result.newlyResolvedProject->products)
+    foreach (const ResolvedProductConstPtr &product, allNewlyResolvedProducts)
         newProductNames += product->name;
 
     const QSet<QString> removedProductsNames = oldProductNames - newProductNames;
     if (!removedProductsNames.isEmpty()) {
-        foreach (const ResolvedProductPtr &product, restoredProject->products) {
+        foreach (const ResolvedProductPtr &product, allRestoredProducts) {
             if (removedProductsNames.contains(product->name))
                 onProductRemoved(product);
         }
@@ -626,10 +704,7 @@ void BuildGraphLoader::trackProjectChanges(const SetupProjectParameters &paramet
         addedProducts.append(freshProduct);
     }
     if (!addedProducts.isEmpty()) {
-        foreach (const ResolvedProductPtr &product, addedProducts) {
-            product->project = restoredProject;
-            restoredProject->products.append(product);
-        }
+        manipulateAddedProducts(allRestoredProjects, allRestoredProducts, addedProducts);
         BuildDataResolver bpr(m_logger);
         bpr.resolveProductBuildDataForExistingProject(restoredProject, addedProducts);
     }
@@ -641,7 +716,7 @@ void BuildGraphLoader::onProductRemoved(const ResolvedProductPtr &product)
 {
     m_logger.qbsDebug() << "[BG] product '" << product->name << "' removed.";
 
-    product->project->buildData->isDirty = true;
+    product->topLevelProject()->buildData->isDirty = true;
     product->project->products.removeOne(product);
 
     // delete all removed artifacts physically from the disk
@@ -681,7 +756,7 @@ void BuildGraphLoader::onProductChanged(const ResolvedProductPtr &product,
             } else {
                 newArtifact = createArtifact(product, a, m_logger);
                 foreach (Artifact *oldArtifact,
-                         product->project->buildData->lookupArtifacts(newArtifact->filePath())) {
+                         product->topLevelProject()->buildData->lookupArtifacts(newArtifact->filePath())) {
                     if (oldArtifact == newArtifact
                             || oldArtifact->artifactType != Artifact::FileDependency) {
                         // The source file already exists in another product.
@@ -747,8 +822,8 @@ void BuildGraphLoader::onProductChanged(const ResolvedProductPtr &product,
     // parents of removed artifacts must update their transformers
     foreach (Artifact *removedArtifact, artifactsToRemove)
         foreach (Artifact *parent, removedArtifact->parents)
-            product->project->buildData->artifactsThatMustGetNewTransformers += parent;
-    product->project->buildData->updateNodesThatMustGetNewTransformer(m_logger);
+            product->topLevelProject()->buildData->artifactsThatMustGetNewTransformers += parent;
+    product->topLevelProject()->buildData->updateNodesThatMustGetNewTransformer(m_logger);
 
     // delete all removed artifacts physically from the disk
     foreach (Artifact *artifact, artifactsToRemove) {
@@ -773,14 +848,14 @@ void BuildGraphLoader::removeArtifactAndExclusiveDependents(Artifact *artifact,
         if (parent->children.isEmpty()) {
             removeParent = true;
         } else if (parent->transformer) {
-            artifact->project->buildData->artifactsThatMustGetNewTransformers += parent;
+            artifact->topLevelProject()->buildData->artifactsThatMustGetNewTransformers += parent;
             parent->transformer->inputs.remove(artifact);
             removeParent = parent->transformer->inputs.isEmpty();
         }
         if (removeParent)
             removeArtifactAndExclusiveDependents(parent, removedArtifacts);
     }
-    artifact->project->buildData->removeArtifact(artifact, m_logger);
+    artifact->topLevelProject()->buildData->removeArtifact(artifact, m_logger);
 }
 
 bool BuildGraphLoader::checkForPropertyChanges(const TransformerPtr &restoredTrafo,
@@ -824,8 +899,8 @@ void BuildGraphLoader::replaceFileDependencyWithArtifact(Artifact *filedep, Arti
             artifactInProduct->fileDependencies.remove(filedep);
         }
     }
-    filedep->project->buildData->dependencyArtifacts.remove(filedep);
-    filedep->project->buildData->removeFromArtifactLookupTable(filedep);
+    filedep->topLevelProject()->buildData->dependencyArtifacts.remove(filedep);
+    filedep->topLevelProject()->buildData->removeFromArtifactLookupTable(filedep);
     delete filedep;
 }
 
diff --git a/src/lib/buildgraph/buildgraph.h b/src/lib/buildgraph/buildgraph.h
index bf1256756..47798d73a 100644
--- a/src/lib/buildgraph/buildgraph.h
+++ b/src/lib/buildgraph/buildgraph.h
@@ -90,8 +90,8 @@ public:
     public:
         LoadResult() : discardLoadedProject(false) {}
 
-        ResolvedProjectPtr newlyResolvedProject;
-        ResolvedProjectPtr loadedProject;
+        TopLevelProjectPtr newlyResolvedProject;
+        TopLevelProjectPtr loadedProject;
         bool discardLoadedProject;
     };
 
@@ -101,7 +101,7 @@ public:
 private:
     void trackProjectChanges(const SetupProjectParameters &parameters,
                              const QString &buildGraphFilePath,
-                             const ResolvedProjectPtr &restoredProject);
+                             const TopLevelProjectPtr &restoredProject);
     void onProductRemoved(const ResolvedProductPtr &product);
     void onProductChanged(const ResolvedProductPtr &product,
                           const ResolvedProductPtr &changedProduct);
diff --git a/src/lib/buildgraph/cycledetector.cpp b/src/lib/buildgraph/cycledetector.cpp
index 3e39b70c9..28e027d93 100644
--- a/src/lib/buildgraph/cycledetector.cpp
+++ b/src/lib/buildgraph/cycledetector.cpp
@@ -46,7 +46,7 @@ CycleDetector::CycleDetector(const Logger &logger)
 void CycleDetector::visitProject(const ResolvedProjectConstPtr &project)
 {
     const QString description = QString::fromLocal8Bit("Cycle detection for project '%1'")
-                .arg(project->id());
+            .arg(project->name);
     TimedActivityLogger timeLogger(m_logger, description, QLatin1String("[BG] "), LoggerTrace);
     ArtifactVisitor::visitProject(project);
 }
diff --git a/src/lib/buildgraph/executor.cpp b/src/lib/buildgraph/executor.cpp
index a312c4785..4b00e1008 100644
--- a/src/lib/buildgraph/executor.cpp
+++ b/src/lib/buildgraph/executor.cpp
@@ -161,7 +161,7 @@ void Executor::build()
     }
 }
 
-void Executor::setProject(const ResolvedProjectPtr &project)
+void Executor::setProject(const TopLevelProjectPtr &project)
 {
     m_project = project;
 }
@@ -632,7 +632,7 @@ void Executor::doSanityChecks()
     QBS_CHECK(!m_productsToBuild.isEmpty());
     foreach (const ResolvedProductConstPtr &product, m_productsToBuild) {
         QBS_CHECK(product->buildData);
-        QBS_CHECK(product->project == m_project);
+        QBS_CHECK(product->topLevelProject() == m_project);
     }
 }
 
@@ -711,7 +711,7 @@ void Executor::onProcessSuccess()
         QBS_CHECK(processedArtifact);
 
         // Update the timestamps of the outputs of the transformer we just executed.
-        processedArtifact->project->buildData->isDirty = true;
+        processedArtifact->topLevelProject()->buildData->isDirty = true;
         foreach (Artifact *artifact, processedArtifact->transformer->outputs) {
             if (artifact->alwaysUpdated)
                 artifact->timestamp = FileTime::currentTime();
diff --git a/src/lib/buildgraph/executor.h b/src/lib/buildgraph/executor.h
index 0cece1cd2..7a55adf64 100644
--- a/src/lib/buildgraph/executor.h
+++ b/src/lib/buildgraph/executor.h
@@ -62,7 +62,7 @@ public:
     Executor(const Logger &logger, QObject *parent = 0);
     ~Executor();
 
-    void setProject(const ResolvedProjectPtr &project);
+    void setProject(const TopLevelProjectPtr &project);
     void setProducts(const QList<ResolvedProductPtr> &productsToBuild);
     void setBuildOptions(const BuildOptions &buildOptions);
     void setProgressObserver(ProgressObserver *observer) { m_progressObserver = observer; }
@@ -120,7 +120,7 @@ private:
     QList<ExecutorJob*> m_availableJobs;
     QHash<ExecutorJob*, Artifact *> m_processingJobs;
     ExecutorState m_state;
-    ResolvedProjectPtr m_project;
+    TopLevelProjectPtr m_project;
     QList<ResolvedProductPtr> m_productsToBuild;
     QList<Artifact *> m_roots;
     QList<Artifact *> m_leaves;
diff --git a/src/lib/buildgraph/inputartifactscanner.cpp b/src/lib/buildgraph/inputartifactscanner.cpp
index f2ea1220d..f6863bc3b 100644
--- a/src/lib/buildgraph/inputartifactscanner.cpp
+++ b/src/lib/buildgraph/inputartifactscanner.cpp
@@ -88,12 +88,12 @@ static void resolveWithIncludePath(const QString &includePath,
     if (!dependency.isClean())
         absDirPath = QDir::cleanPath(absDirPath);
 
-    const ResolvedProject *project = product->project.data();
+    ResolvedProject *project = product->project.data();
     Artifact *fileDependencyArtifact = 0;
     Artifact *dependencyInProduct = 0;
     Artifact *dependencyInOtherProduct = 0;
-    foreach (Artifact *artifact,
-             project->buildData->lookupArtifacts(absDirPath, dependency.fileName())) {
+    foreach (Artifact *artifact, project->topLevelProject()
+             ->buildData->lookupArtifacts(absDirPath, dependency.fileName())) {
         if (artifact->artifactType == Artifact::FileDependency)
             fileDependencyArtifact = artifact;
         else if (artifact->product == product)
@@ -319,7 +319,7 @@ void InputArtifactScanner::handleDependency(ResolvedDependency &dependency)
         dependency.artifact->artifactType = Artifact::FileDependency;
         dependency.artifact->properties = m_artifact->properties;
         dependency.artifact->setFilePath(dependency.filePath);
-        m_artifact->project->buildData->insertFileDependency(dependency.artifact);
+        m_artifact->topLevelProject()->buildData->insertFileDependency(dependency.artifact);
     } else if (dependency.artifact->artifactType == Artifact::FileDependency) {
         // The dependency exists in the project's list of file dependencies.
         if (m_logger.traceEnabled()) {
diff --git a/src/lib/buildgraph/productinstaller.cpp b/src/lib/buildgraph/productinstaller.cpp
index 310f45786..93ac80ffa 100644
--- a/src/lib/buildgraph/productinstaller.cpp
+++ b/src/lib/buildgraph/productinstaller.cpp
@@ -35,6 +35,7 @@
 #include <tools/qbsassert.h>
 #include <tools/error.h>
 #include <tools/fileinfo.h>
+#include <tools/propertyfinder.h>
 #include <tools/progressobserver.h>
 #include <tools/qbsassert.h>
 
@@ -44,8 +45,9 @@
 namespace qbs {
 namespace Internal {
 
-ProductInstaller::ProductInstaller(const QList<ResolvedProductPtr> &products,
-        const InstallOptions &options, ProgressObserver *observer, const Logger &logger)
+ProductInstaller::ProductInstaller(const TopLevelProjectPtr &project,
+        const QList<ResolvedProductPtr> &products, const InstallOptions &options,
+        ProgressObserver *observer, const Logger &logger)
     : m_products(products), m_options(options), m_observer(observer), m_logger(logger)
 {
     if (!m_options.installRoot().isEmpty()) {
@@ -61,18 +63,14 @@ ProductInstaller::ProductInstaller(const QList<ResolvedProductPtr> &products,
         return;
     }
 
-    if (m_products.isEmpty())
-        throw Error(Tr::tr("Cannot deduce install root, because there are no products."));
-
-    const ResolvedProductConstPtr &product = m_products.first();
     if (m_options.installIntoSysroot()) {
         if (m_options.removeExistingInstallation())
             throw Error(Tr::tr("Refusing to remove sysroot."));
-        m_options.setInstallRoot(product->properties
-                                 ->qbsPropertyValue(QLatin1String("sysroot")).toString());
+        m_options.setInstallRoot(PropertyFinder().propertyValue(project->buildConfiguration(),
+                QLatin1String("qbs"), QLatin1String("sysroot")).toString());
     } else {
-        m_options.setInstallRoot(product->project->buildDirectory
-            + QLatin1Char('/') + InstallOptions::defaultInstallRoot());
+        m_options.setInstallRoot(project->buildDirectory + QLatin1Char('/') +
+                                 InstallOptions::defaultInstallRoot());
     }
 }
 
@@ -119,7 +117,7 @@ void ProductInstaller::copyFile(const Artifact *artifact)
 {
     if (m_observer->canceled()) {
         throw Error(Tr::tr("Installation canceled for configuration '%1'.")
-                    .arg(m_products.first()->project->id()));
+                    .arg(m_products.first()->project->topLevelProject()->id()));
     }
     const QString relativeInstallDir
             = artifact->properties->qbsPropertyValue(QLatin1String("installDir")).toString();
diff --git a/src/lib/buildgraph/productinstaller.h b/src/lib/buildgraph/productinstaller.h
index acea496f1..1c711f02a 100644
--- a/src/lib/buildgraph/productinstaller.h
+++ b/src/lib/buildgraph/productinstaller.h
@@ -44,8 +44,8 @@ class ProgressObserver;
 class ProductInstaller
 {
 public:
-    ProductInstaller(const QList<ResolvedProductPtr> &products, const InstallOptions &options,
-                     ProgressObserver *observer, const Logger &logger);
+    ProductInstaller(const TopLevelProjectPtr &project, const QList<ResolvedProductPtr> &products,
+            const InstallOptions &options, ProgressObserver *observer, const Logger &logger);
     void install();
 
 private:
diff --git a/src/lib/buildgraph/projectbuilddata.cpp b/src/lib/buildgraph/projectbuilddata.cpp
index c2adde294..b885254ac 100644
--- a/src/lib/buildgraph/projectbuilddata.cpp
+++ b/src/lib/buildgraph/projectbuilddata.cpp
@@ -46,7 +46,7 @@
 namespace qbs {
 namespace Internal {
 
-ProjectBuildData::ProjectBuildData() : isDirty(false)
+ProjectBuildData::ProjectBuildData() : isDirty(true)
 {
 }
 
@@ -187,16 +187,17 @@ BuildDataResolver::BuildDataResolver(const Logger &logger) : m_logger(logger)
 {
 }
 
-void BuildDataResolver::resolveBuildData(const ResolvedProjectPtr &resolvedProject,
+void BuildDataResolver::resolveBuildData(const TopLevelProjectPtr &resolvedProject,
                                           const RulesEvaluationContextPtr &evalContext)
 {
     QBS_CHECK(!resolvedProject->buildData);
     m_project = resolvedProject;
     resolvedProject->buildData.reset(new ProjectBuildData);
     resolvedProject->buildData->evaluationContext = evalContext;
+    const QList<ResolvedProductPtr> allProducts = resolvedProject->allProducts();
     evalContext->initializeObserver(Tr::tr("Setting up build graph for configuration %1")
-                                    .arg(resolvedProject->id()), resolvedProject->products.count());
-    foreach (ResolvedProductPtr rProduct, resolvedProject->products) {
+                                    .arg(resolvedProject->id()), allProducts.count());
+    foreach (ResolvedProductPtr rProduct, allProducts) {
         if (rProduct->enabled)
             resolveProductBuildData(rProduct);
         evalContext->incrementProgressValue();
@@ -204,7 +205,7 @@ void BuildDataResolver::resolveBuildData(const ResolvedProjectPtr &resolvedProje
     CycleDetector(m_logger).visitProject(m_project);
 }
 
-void BuildDataResolver::resolveProductBuildDataForExistingProject(const ResolvedProjectPtr &project,
+void BuildDataResolver::resolveProductBuildDataForExistingProject(const TopLevelProjectPtr &project,
         const QList<ResolvedProductPtr> &freshProducts)
 {
     m_project = project;
@@ -217,8 +218,8 @@ void BuildDataResolver::resolveProductBuildDataForExistingProject(const Resolved
  *    - dependencies between artifacts,
  *    - time stamps of artifacts, if their commands have not changed.
  */
-void BuildDataResolver::rescueBuildData(const ResolvedProjectConstPtr &source,
-                                      const ResolvedProjectPtr &target, Logger logger)
+void BuildDataResolver::rescueBuildData(const TopLevelProjectConstPtr &source,
+                                      const TopLevelProjectPtr &target, Logger logger)
 {
     QHash<QString, ResolvedProductConstPtr> sourceProductsByName;
     foreach (const ResolvedProductConstPtr &product, source->products)
@@ -295,7 +296,7 @@ void BuildDataResolver::resolveProductBuildData(const ResolvedProductPtr &produc
     //add qbsFile artifact
     Artifact *qbsFileArtifact = lookupArtifact(product, product->location.fileName());
     if (!qbsFileArtifact) {
-        qbsFileArtifact = new Artifact(m_project);
+        qbsFileArtifact = new Artifact(product->project);
         qbsFileArtifact->artifactType = Artifact::SourceFile;
         qbsFileArtifact->setFilePath(product->location.fileName());
         qbsFileArtifact->properties = product->properties;
diff --git a/src/lib/buildgraph/projectbuilddata.h b/src/lib/buildgraph/projectbuilddata.h
index ee656af7e..334cf8e75 100644
--- a/src/lib/buildgraph/projectbuilddata.h
+++ b/src/lib/buildgraph/projectbuilddata.h
@@ -81,13 +81,13 @@ class BuildDataResolver
 {
 public:
     BuildDataResolver(const Logger &logger);
-    void resolveBuildData(const ResolvedProjectPtr &resolvedProject,
+    void resolveBuildData(const TopLevelProjectPtr &resolvedProject,
                           const RulesEvaluationContextPtr &evalContext);
-    void resolveProductBuildDataForExistingProject(const ResolvedProjectPtr &project,
+    void resolveProductBuildDataForExistingProject(const TopLevelProjectPtr &project,
             const QList<ResolvedProductPtr> &freshProducts);
 
-    static void rescueBuildData(const ResolvedProjectConstPtr &source,
-                                const ResolvedProjectPtr &target, Logger logger);
+    static void rescueBuildData(const TopLevelProjectConstPtr &source,
+                                const TopLevelProjectPtr &target, Logger logger);
 
 private:
     void resolveProductBuildData(const ResolvedProductPtr &product);
@@ -95,7 +95,7 @@ private:
     ScriptEngine *engine() const;
     QScriptValue scope() const;
 
-    ResolvedProjectPtr m_project;
+    TopLevelProjectPtr m_project;
     Logger m_logger;
 };
 
diff --git a/src/lib/buildgraph/rulesapplicator.cpp b/src/lib/buildgraph/rulesapplicator.cpp
index 96054c328..11405a716 100644
--- a/src/lib/buildgraph/rulesapplicator.cpp
+++ b/src/lib/buildgraph/rulesapplicator.cpp
@@ -59,7 +59,7 @@ RulesApplicator::RulesApplicator(const ResolvedProductPtr &product,
 
 void RulesApplicator::applyAllRules()
 {
-    RulesEvaluationContext::Scope s(m_product->project->buildData->evaluationContext.data());
+    RulesEvaluationContext::Scope s(m_product->topLevelProject()->buildData->evaluationContext.data());
     foreach (const RuleConstPtr &rule, m_product->topSortedRules())
         applyRule(rule);
 }
@@ -147,7 +147,8 @@ void RulesApplicator::doApply(const ArtifactList &inputArtifacts)
         }
         m_transformer->outputs.insert(outputArtifact);
 
-        m_product->project->buildData->artifactsThatMustGetNewTransformers -= outputArtifact;
+        m_product->topLevelProject()->buildData->artifactsThatMustGetNewTransformers
+                -= outputArtifact;
     }
 
     m_transformer->setupInputs(engine(), scope());
@@ -199,7 +200,7 @@ void RulesApplicator::setupScriptEngineForArtifact(Artifact *artifact)
         QDir sourceDir(m_product->sourceDirectory);
         basedir = FileInfo::path(sourceDir.relativeFilePath(artifact->filePath()));
     } else {
-        QDir buildDir(m_product->project->buildDirectory);
+        QDir buildDir(m_product->topLevelProject()->buildDirectory);
         basedir = FileInfo::path(buildDir.relativeFilePath(artifact->filePath()));
     }
 
@@ -303,7 +304,7 @@ Artifact *RulesApplicator::createOutputArtifact(const RuleArtifactConstPtr &rule
 
 QString RulesApplicator::resolveOutPath(const QString &path) const
 {
-    QString buildDir = m_product->project->buildDirectory;
+    QString buildDir = m_product->topLevelProject()->buildDirectory;
     QString result = FileInfo::resolvePath(buildDir, path);
     result = QDir::cleanPath(result);
     return result;
@@ -311,7 +312,7 @@ QString RulesApplicator::resolveOutPath(const QString &path) const
 
 RulesEvaluationContextPtr RulesApplicator::evalContext() const
 {
-    return m_product->project->buildData->evaluationContext;
+    return m_product->topLevelProject()->buildData->evaluationContext;
 }
 
 ScriptEngine *RulesApplicator::engine() const
diff --git a/src/lib/buildgraph/timestampsupdater.cpp b/src/lib/buildgraph/timestampsupdater.cpp
index 9c338a965..44130b06f 100644
--- a/src/lib/buildgraph/timestampsupdater.cpp
+++ b/src/lib/buildgraph/timestampsupdater.cpp
@@ -70,7 +70,7 @@ private:
     FileTime m_now;
 };
 
-void TimestampsUpdater::updateTimestamps(const ResolvedProjectPtr &project,
+void TimestampsUpdater::updateTimestamps(const TopLevelProjectPtr &project,
         const QList<ResolvedProductPtr> &products, const Logger &logger)
 {
     TimestampsUpdateVisitor v;
diff --git a/src/lib/buildgraph/timestampsupdater.h b/src/lib/buildgraph/timestampsupdater.h
index 561714ea4..8505b8f34 100644
--- a/src/lib/buildgraph/timestampsupdater.h
+++ b/src/lib/buildgraph/timestampsupdater.h
@@ -40,7 +40,7 @@ class Logger;
 class TimestampsUpdater
 {
 public:
-    void updateTimestamps(const ResolvedProjectPtr &project,
+    void updateTimestamps(const TopLevelProjectPtr &project,
                           const QList<ResolvedProductPtr> &products, const Logger &logger);
 };
 
diff --git a/src/lib/language/builtindeclarations.cpp b/src/lib/language/builtindeclarations.cpp
index 9697c82d8..1df7649a9 100644
--- a/src/lib/language/builtindeclarations.cpp
+++ b/src/lib/language/builtindeclarations.cpp
@@ -251,6 +251,8 @@ void BuiltinDeclarations::addProductItem()
 void BuiltinDeclarations::addProjectItem()
 {
     QList<PropertyDeclaration> properties;
+    properties += nameProperty();
+    properties += conditionProperty();
     properties += PropertyDeclaration(QLatin1String("references"), PropertyDeclaration::Variant,
                                       PropertyDeclaration::PropertyNotAvailableInConfig);
     properties += PropertyDeclaration(QLatin1String("moduleSearchPaths"),
@@ -280,6 +282,18 @@ void BuiltinDeclarations::addRuleItem()
     m_builtins[QLatin1String("Rule")] = properties;
 }
 
+void BuiltinDeclarations::addSubprojectItem()
+{
+    QList<PropertyDeclaration> properties;
+    properties += PropertyDeclaration(QLatin1String("filePath"), PropertyDeclaration::Path);
+    PropertyDeclaration inheritProperty;
+    inheritProperty.name = QLatin1String("inheritProperties");
+    inheritProperty.type = PropertyDeclaration::Boolean;
+    inheritProperty.initialValueSource = QLatin1String("true");
+    properties += inheritProperty;
+    m_builtins[QLatin1String("SubProject")] = properties;
+}
+
 void BuiltinDeclarations::addTransformerItem()
 {
     QList<PropertyDeclaration> properties;
diff --git a/src/lib/language/builtindeclarations.h b/src/lib/language/builtindeclarations.h
index 1f5869b53..7f5ddeda6 100644
--- a/src/lib/language/builtindeclarations.h
+++ b/src/lib/language/builtindeclarations.h
@@ -58,6 +58,7 @@ private:
     void addProjectItem();
     void addPropertyOptionsItem();
     void addRuleItem();
+    void addSubprojectItem();
     void addTransformerItem();
 
     QString m_languageVersion;
diff --git a/src/lib/language/evaluator.cpp b/src/lib/language/evaluator.cpp
index 12ec26d7b..e80351ca3 100644
--- a/src/lib/language/evaluator.cpp
+++ b/src/lib/language/evaluator.cpp
@@ -31,10 +31,12 @@
 #include "evaluationdata.h"
 #include "evaluatorscriptclass.h"
 #include "filecontext.h"
+#include "filetags.h"
 #include "item.h"
 #include <logging/translator.h>
 #include <tools/error.h>
 #include <tools/qbsassert.h>
+#include <tools/scripttools.h>
 #include <QDebug>
 #include <QScriptEngine>
 
@@ -82,6 +84,57 @@ QScriptValue Evaluator::property(const Item *item, const QStringList &nameParts)
     return property(targetItem, nameParts.last());
 }
 
+bool Evaluator::boolValue(const Item *item, const QString &name, bool defaultValue,
+                          bool *propertyWasSet)
+{
+    QScriptValue v = property(item, name);
+    if (Q_UNLIKELY(v.isError())) {
+        ValuePtr value = item->property(name);
+        throw Error(v.toString(), value ? value->location() : CodeLocation());
+    }
+    if (!v.isValid() || v.isUndefined()) {
+        if (propertyWasSet)
+            *propertyWasSet = false;
+        return defaultValue;
+    }
+    if (propertyWasSet)
+        *propertyWasSet = true;
+    return v.toBool();
+}
+
+FileTags Evaluator::fileTagsValue(const Item *item, const QString &name)
+{
+    return FileTags::fromStringList(stringListValue(item, name));
+}
+
+QString Evaluator::stringValue(const Item *item, const QString &name,
+                               const QString &defaultValue, bool *propertyWasSet)
+{
+    QScriptValue v = property(item, name);
+    if (Q_UNLIKELY(v.isError())) {
+        ValuePtr value = item->property(name);
+        throw Error(v.toString(), value ? value->location() : CodeLocation());
+    }
+    if (!v.isValid() || v.isUndefined()) {
+        if (propertyWasSet)
+            *propertyWasSet = false;
+        return defaultValue;
+    }
+    if (propertyWasSet)
+        *propertyWasSet = true;
+    return v.toString();
+}
+
+QStringList Evaluator::stringListValue(const Item *item, const QString &name)
+{
+    QScriptValue v = property(item, name);
+    if (Q_UNLIKELY(v.isError())) {
+        ValuePtr value = item->property(name);
+        throw Error(v.toString(), value ? value->location() : CodeLocation());
+    }
+    return toStringList(v);
+}
+
 QScriptValue Evaluator::scriptValue(const Item *item)
 {
     QScriptValue &scriptValue = m_scriptValueMap[item];
diff --git a/src/lib/language/evaluator.h b/src/lib/language/evaluator.h
index 9262cc48d..54ae6b24d 100644
--- a/src/lib/language/evaluator.h
+++ b/src/lib/language/evaluator.h
@@ -39,6 +39,7 @@
 
 namespace qbs {
 namespace Internal {
+class FileTags;
 
 class EvaluatorScriptClass;
 
@@ -53,6 +54,14 @@ public:
     ScriptEngine *engine() const;
     QScriptValue property(const Item *item, const QString &name);
     QScriptValue property(const Item *item, const QStringList &nameParts);
+
+    bool boolValue(const Item *item, const QString &name, bool defaultValue = false,
+                   bool *propertyWasSet = 0);
+    FileTags fileTagsValue(const Item *item, const QString &name);
+    QString stringValue(const Item *item, const QString &name,
+                        const QString &defaultValue = QString(), bool *propertyWasSet = 0);
+    QStringList stringListValue(const Item *item, const QString &name);
+
     QScriptValue scriptValue(const Item *item);
     QScriptValue fileScope(const FileContextConstPtr &file);
 
diff --git a/src/lib/language/forward_decls.h b/src/lib/language/forward_decls.h
index cd6117412..f05148902 100644
--- a/src/lib/language/forward_decls.h
+++ b/src/lib/language/forward_decls.h
@@ -74,6 +74,10 @@ class ResolvedProject;
 typedef QSharedPointer<ResolvedProject> ResolvedProjectPtr;
 typedef QSharedPointer<const ResolvedProject> ResolvedProjectConstPtr;
 
+class TopLevelProject;
+typedef QSharedPointer<TopLevelProject> TopLevelProjectPtr;
+typedef QSharedPointer<const TopLevelProject> TopLevelProjectConstPtr;
+
 class Rule;
 typedef QSharedPointer<Rule> RulePtr;
 typedef QSharedPointer<const Rule> RuleConstPtr;
diff --git a/src/lib/language/item.h b/src/lib/language/item.h
index 12380aaec..d298c9788 100644
--- a/src/lib/language/item.h
+++ b/src/lib/language/item.h
@@ -37,6 +37,7 @@
 #include "propertydeclaration.h"
 #include <parser/qmljsmemorypool_p.h>
 #include <tools/codelocation.h>
+#include <tools/error.h>
 #include <tools/weakpointer.h>
 
 #include <QList>
@@ -70,6 +71,8 @@ public:
         Item *item;
     };
     typedef QList<Module> Modules;
+    typedef QMap<QString, PropertyDeclaration> PropertyDeclarationMap;
+    typedef QMap<QString, ValuePtr> PropertyMap;
 
     static Item *create(ItemPool *pool);
     Item *clone(ItemPool *pool) const;
@@ -85,10 +88,11 @@ public:
     Item *parent() const;
     const FileContextPtr file() const;
     QList<Item *> children() const;
-    const QMap<QString, ValuePtr> &properties() const;
-    const QMap<QString, PropertyDeclaration> &propertyDeclarations() const;
+    const PropertyMap &properties() const;
+    const PropertyDeclarationMap &propertyDeclarations() const;
     const Modules &modules() const;
     Modules &modules();
+    const Error &error() const { return m_error; }
 
     bool hasProperty(const QString &name) const;
     bool hasOwnProperty(const QString &name) const;
@@ -97,6 +101,7 @@ public:
     JSSourceValuePtr sourceProperty(const QString &name) const;
     void setPropertyObserver(ItemObserver *observer) const;
     void setProperty(const QString &name, const ValuePtr &value);
+    void setPropertyDeclaration(const QString &name, const PropertyDeclaration &declaration);
     void setTypeName(const QString &name);
     void setLocation(const CodeLocation &location);
     void setPrototype(Item *prototype);
@@ -107,6 +112,7 @@ public:
     void setChildren(const QList<Item *> &children);
     void setParent(Item *item);
     static void addChild(Item *parent, Item *child);
+    void setError(const Error &error) { m_error = error; }
 
 private:
     ItemPool *m_pool;
@@ -121,10 +127,11 @@ private:
     Item *m_parent;
     QList<Item *> m_children;
     FileContextPtr m_file;
-    QMap<QString, ValuePtr> m_properties;
-    QMap<QString, PropertyDeclaration> m_propertyDeclarations;
+    PropertyMap m_properties;
+    PropertyDeclarationMap m_propertyDeclarations;
     QList<FunctionDeclaration> m_functions;
     Modules m_modules;
+    Error m_error; // For SubProject items. May or may not be reported depending on their condition.
 };
 
 inline ItemPool *Item::pool() const
@@ -182,12 +189,12 @@ inline QList<Item *> Item::children() const
     return m_children;
 }
 
-inline const QMap<QString, ValuePtr> &Item::properties() const
+inline const Item::PropertyMap &Item::properties() const
 {
     return m_properties;
 }
 
-inline const QMap<QString, PropertyDeclaration> &Item::propertyDeclarations() const
+inline const Item::PropertyDeclarationMap &Item::propertyDeclarations() const
 {
     return m_propertyDeclarations;
 }
@@ -199,6 +206,12 @@ inline void Item::setProperty(const QString &name, const ValuePtr &value)
         m_propertyObserver->onItemPropertyChanged(this);
 }
 
+inline void Item::setPropertyDeclaration(const QString &name,
+                                         const PropertyDeclaration &declaration)
+{
+    m_propertyDeclarations.insert(name, declaration);
+}
+
 inline void Item::setTypeName(const QString &name)
 {
     m_typeName = name;
diff --git a/src/lib/language/itemreaderastvisitor.cpp b/src/lib/language/itemreaderastvisitor.cpp
index e3fcaac78..dd4be9350 100644
--- a/src/lib/language/itemreaderastvisitor.cpp
+++ b/src/lib/language/itemreaderastvisitor.cpp
@@ -252,8 +252,10 @@ bool ItemReaderASTVisitor::visit(AST::UiObjectDefinition *ast)
         }
     }
 
-    if (item->typeName() != QLatin1String("Properties"))
+    if (item->typeName() != QLatin1String("Properties")
+            && item->typeName() != QLatin1String("SubProject")) {
         setupAlternatives(item);
+    }
 
     // resolve inheritance
     const QStringList fullTypeName = toStringList(ast->qualifiedTypeNameId);
diff --git a/src/lib/language/language.cpp b/src/lib/language/language.cpp
index 25f09df5e..51586ef57 100644
--- a/src/lib/language/language.cpp
+++ b/src/lib/language/language.cpp
@@ -441,7 +441,7 @@ enum EnvType
 static QProcessEnvironment getProcessEnvironment(ScriptEngine *engine, EnvType envType,
                                                  const QList<ResolvedModuleConstPtr> &modules,
                                                  const PropertyMapConstPtr &productConfiguration,
-                                                 ResolvedProject *project,
+                                                 TopLevelProject *project,
                                                  const QProcessEnvironment &env)
 {
     QProcessEnvironment procenv = env;
@@ -541,7 +541,8 @@ void ResolvedProduct::setupBuildEnvironment(ScriptEngine *engine, const QProcess
     if (!buildEnvironment.isEmpty())
         return;
 
-    buildEnvironment = getProcessEnvironment(engine, BuildEnv, modules, properties, project, env);
+    buildEnvironment = getProcessEnvironment(engine, BuildEnv, modules, properties,
+                                             topLevelProject(), env);
 }
 
 void ResolvedProduct::setupRunEnvironment(ScriptEngine *engine, const QProcessEnvironment &env) const
@@ -549,7 +550,8 @@ void ResolvedProduct::setupRunEnvironment(ScriptEngine *engine, const QProcessEn
     if (!runEnvironment.isEmpty())
         return;
 
-    runEnvironment = getProcessEnvironment(engine, RunEnv, modules, properties, project, env);
+    runEnvironment = getProcessEnvironment(engine, RunEnv, modules, properties,
+                                           topLevelProject(), env);
 }
 
 const QList<RuleConstPtr> &ResolvedProduct::topSortedRules() const
@@ -568,8 +570,107 @@ const QList<RuleConstPtr> &ResolvedProduct::topSortedRules() const
     return buildData->topSortedRules;
 }
 
+TopLevelProject *ResolvedProduct::topLevelProject() const
+{
+     return project->topLevelProject();
+}
+
+
+ResolvedProject::ResolvedProject() : enabled(true), m_topLevelProject(0)
+{
+}
+
+TopLevelProject *ResolvedProject::topLevelProject()
+{
+    if (m_topLevelProject)
+        return m_topLevelProject;
+    TopLevelProject *tlp = dynamic_cast<TopLevelProject *>(this);
+    if (tlp) {
+        m_topLevelProject = tlp;
+        return m_topLevelProject;
+    }
+    QBS_CHECK(!parentProject.isNull());
+    m_topLevelProject = parentProject->topLevelProject();
+    return m_topLevelProject;
+}
+
+QList<ResolvedProjectPtr> ResolvedProject::allSubProjects() const
+{
+    QList<ResolvedProjectPtr> projectList = subProjects;
+    foreach (const ResolvedProjectConstPtr &subProject, subProjects)
+        projectList << subProject->allSubProjects();
+    return projectList;
+}
+
+QList<ResolvedProductPtr> ResolvedProject::allProducts() const
+{
+    QList<ResolvedProductPtr> productList = products;
+    foreach (const ResolvedProjectConstPtr &subProject, subProjects)
+        productList << subProject->allProducts();
+    return productList;
+}
+
+void ResolvedProject::load(PersistentPool &pool)
+{
+    name = pool.idLoadString();
+    const QString fileName = pool.idLoadString();
+    int line;
+    int column;
+    pool.stream() >> line;
+    pool.stream() >> column;
+    location = CodeLocation(fileName, line, column);
+    pool.stream() >> enabled;
 
-QString ResolvedProject::deriveId(const QVariantMap &config)
+    int count;
+    pool.stream() >> count;
+    products.clear();
+    products.reserve(count);
+    for (; --count >= 0;) {
+        ResolvedProductPtr rProduct = pool.idLoadS<ResolvedProduct>();
+        if (rProduct->buildData) {
+            foreach (Artifact * const a, rProduct->buildData->artifacts)
+                a->product = rProduct;
+        }
+        products.append(rProduct);
+    }
+
+    pool.stream() >> count;
+    subProjects.clear();
+    subProjects.reserve(count);
+    for (; --count >= 0;) {
+        ResolvedProjectPtr p = pool.idLoadS<ResolvedProject>();
+        subProjects.append(p);
+    }
+
+    pool.stream() >> m_projectProperties;
+}
+
+void ResolvedProject::store(PersistentPool &pool) const
+{
+    pool.storeString(name);
+    pool.storeString(location.fileName());
+    pool.stream() << location.line();
+    pool.stream() << location.column();
+    pool.stream() << enabled;
+    pool.stream() << products.count();
+    foreach (const ResolvedProductConstPtr &product, products)
+        pool.store(product);
+    pool.stream() << subProjects.count();
+    foreach (const ResolvedProjectConstPtr &project, subProjects)
+        pool.store(project);
+    pool.stream() << m_projectProperties;
+}
+
+
+TopLevelProject::TopLevelProject()
+{
+}
+
+TopLevelProject::~TopLevelProject()
+{
+}
+
+QString TopLevelProject::deriveId(const QVariantMap &config)
 {
     const QVariantMap qbsProperties = config.value(QLatin1String("qbs")).toMap();
     const QString buildVariant = qbsProperties.value(QLatin1String("buildVariant")).toString();
@@ -577,28 +678,23 @@ QString ResolvedProject::deriveId(const QVariantMap &config)
     return profile + QLatin1Char('-') + buildVariant;
 }
 
-QString ResolvedProject::deriveBuildDirectory(const QString &buildRoot, const QString &id)
+QString TopLevelProject::deriveBuildDirectory(const QString &buildRoot, const QString &id)
 {
     return buildRoot + QLatin1Char('/') + id;
 }
 
-void ResolvedProject::setBuildConfiguration(const QVariantMap &config)
+void TopLevelProject::setBuildConfiguration(const QVariantMap &config)
 {
     m_buildConfiguration = config;
     m_id = deriveId(config);
 }
 
-void ResolvedProject::setProjectProperties(const QVariantMap &config)
-{
-    m_projectProperties = config;
-}
-
-QString ResolvedProject::buildGraphFilePath() const
+QString TopLevelProject::buildGraphFilePath() const
 {
     return ProjectBuildData::deriveBuildGraphFilePath(buildDirectory, id());
 }
 
-void ResolvedProject::store(const Logger &logger) const
+void TopLevelProject::store(const Logger &logger) const
 {
     // TODO: Use progress observer here.
 
@@ -619,65 +715,29 @@ void ResolvedProject::store(const Logger &logger) const
     buildData->isDirty = false;
 }
 
-ResolvedProject::ResolvedProject()
-{
-}
-
-ResolvedProject::~ResolvedProject()
+void TopLevelProject::load(PersistentPool &pool)
 {
-}
-
-void ResolvedProject::load(PersistentPool &pool)
-{
-    const QString fileName = pool.idLoadString();
-    int line;
-    int column;
-    pool.stream() >> line;
-    pool.stream() >> column;
-    location = CodeLocation(fileName, line, column);
+    ResolvedProject::load(pool);
     pool.stream() >> m_id;
     pool.stream() >> platformEnvironment;
-
-    int count;
-    pool.stream() >> count;
-    products.clear();
-    products.reserve(count);
-    for (; --count >= 0;) {
-        ResolvedProductPtr rProduct = pool.idLoadS<ResolvedProduct>();
-        if (rProduct->buildData) {
-            foreach (Artifact * const a, rProduct->buildData->artifacts)
-                a->product = rProduct;
-        }
-        products.append(rProduct);
-    }
+    pool.stream() >> usedEnvironment;
     QHash<QString, QString> envHash;
-    pool.stream()
-        >> usedEnvironment
-        >> m_projectProperties
-        >> envHash;
+    pool.stream() >> envHash;
     for (QHash<QString, QString>::const_iterator i = envHash.begin(); i != envHash.end(); ++i)
         environment.insert(i.key(), i.value());
     buildData.reset(pool.idLoad<ProjectBuildData>());
+    buildData->isDirty = false;
 }
 
-void ResolvedProject::store(PersistentPool &pool) const
+void TopLevelProject::store(PersistentPool &pool) const
 {
-    pool.storeString(location.fileName());
-    pool.stream() << location.line();
-    pool.stream() << location.column();
+    ResolvedProject::store(pool);
     pool.stream() << m_id;
-    pool.stream() << platformEnvironment;
-
-    pool.stream() << products.count();
-    foreach (const ResolvedProductConstPtr &product, products)
-        pool.store(product);
+    pool.stream() << platformEnvironment << usedEnvironment;
     QHash<QString, QString> envHash;
     foreach (const QString &key, environment.keys())
         envHash.insert(key, environment.value(key));
-    pool.stream()
-        << usedEnvironment
-        << m_projectProperties
-        << envHash;
+    pool.stream() << envHash;
     pool.store(buildData.data());
 }
 
diff --git a/src/lib/language/language.h b/src/lib/language/language.h
index e41f8d997..4fb477e86 100644
--- a/src/lib/language/language.h
+++ b/src/lib/language/language.h
@@ -273,7 +273,7 @@ private:
     ResolvedTransformer() {}
 };
 
-class ResolvedProject;
+class TopLevelProject;
 class ScriptEngine;
 
 class ResolvedProduct : public PersistentObject
@@ -313,6 +313,7 @@ public:
     void setupRunEnvironment(ScriptEngine *scriptEngine, const QProcessEnvironment &env) const;
 
     const QList<RuleConstPtr> &topSortedRules() const;
+    TopLevelProject *topLevelProject() const;
 
 private:
     ResolvedProduct();
@@ -321,43 +322,67 @@ private:
     void store(PersistentPool &pool) const;
 };
 
-class ResolvedProject: public PersistentObject
+class ResolvedProject : public PersistentObject
+{
+public:
+    static ResolvedProjectPtr create() { return ResolvedProjectPtr(new ResolvedProject); }
+
+    QString name;
+    CodeLocation location;
+    bool enabled;
+    QList<ResolvedProductPtr> products;
+    QList<ResolvedProjectPtr> subProjects;
+    WeakPointer<ResolvedProject> parentProject;
+
+    void setProjectProperties(const QVariantMap &config) { m_projectProperties = config; }
+    const QVariantMap &projectProperties() const { return m_projectProperties; }
+
+    TopLevelProject *topLevelProject();
+    QList<ResolvedProjectPtr> allSubProjects() const;
+    QList<ResolvedProductPtr> allProducts() const;
+
+protected:
+    ResolvedProject();
+
+    void load(PersistentPool &pool);
+    void store(PersistentPool &pool) const;
+private:
+    QVariantMap m_projectProperties;
+    TopLevelProject *m_topLevelProject;
+};
+
+class TopLevelProject : public ResolvedProject
 {
     friend class BuildGraphLoader;
 public:
-    ~ResolvedProject();
+    ~TopLevelProject();
 
-    static ResolvedProjectPtr create() { return ResolvedProjectPtr(new ResolvedProject); }
+    static TopLevelProjectPtr create() { return TopLevelProjectPtr(new TopLevelProject); }
 
     static QString deriveId(const QVariantMap &config);
     static QString deriveBuildDirectory(const QString &buildRoot, const QString &id);
 
-    CodeLocation location;
     QString buildDirectory; // Not saved
     QProcessEnvironment environment;
     QVariantMap platformEnvironment;
     QHash<QString, QString> usedEnvironment; // Environment variables requested by the project while resolving.
-    QList<ResolvedProductPtr> products;
     QScopedPointer<ProjectBuildData> buildData;
 
     void setBuildConfiguration(const QVariantMap &config);
     const QVariantMap &buildConfiguration() const { return m_buildConfiguration; }
-    void setProjectProperties(const QVariantMap &config);
-    const QVariantMap &projectProperties() const { return m_projectProperties; }
     QString id() const { return m_id; }
 
     QString buildGraphFilePath() const;
     void store(const Logger &logger) const;
 
 private:
-    ResolvedProject();
+    TopLevelProject();
 
     void load(PersistentPool &pool);
     void store(PersistentPool &pool) const;
 
-    QVariantMap m_buildConfiguration;
-    QVariantMap m_projectProperties;
     QString m_id;
+    QVariantMap m_buildConfiguration;
 };
 
 } // namespace Internal
diff --git a/src/lib/language/loader.cpp b/src/lib/language/loader.cpp
index 10e36efb8..22a286b48 100644
--- a/src/lib/language/loader.cpp
+++ b/src/lib/language/loader.cpp
@@ -82,7 +82,7 @@ void Loader::setSearchPaths(const QStringList &_searchPaths)
     m_moduleLoader->setSearchPaths(searchPaths);
 }
 
-ResolvedProjectPtr Loader::loadProject(const SetupProjectParameters &parameters)
+TopLevelProjectPtr Loader::loadProject(const SetupProjectParameters &parameters)
 {
     QBS_CHECK(QFileInfo(parameters.projectFilePath()).isAbsolute());
 
@@ -92,7 +92,7 @@ ResolvedProjectPtr Loader::loadProject(const SetupProjectParameters &parameters)
     // we have enough information.
     if (m_progressObserver) {
         m_progressObserver->initialize(Tr::tr("Resolving project for configuration %1")
-                .arg(ResolvedProject::deriveId(parameters.buildConfiguration())), 1);
+                .arg(TopLevelProject::deriveId(parameters.buildConfiguration())), 1);
     }
     ModuleLoaderResult loadResult
             = m_moduleLoader->load(parameters.projectFilePath(),
diff --git a/src/lib/language/loader.h b/src/lib/language/loader.h
index 12f73b2e7..30ecba75b 100644
--- a/src/lib/language/loader.h
+++ b/src/lib/language/loader.h
@@ -54,7 +54,7 @@ public:
 
     void setProgressObserver(ProgressObserver *observer);
     void setSearchPaths(const QStringList &searchPaths);
-    ResolvedProjectPtr loadProject(const SetupProjectParameters &parameters);
+    TopLevelProjectPtr loadProject(const SetupProjectParameters &parameters);
     QByteArray qmlTypeInfo();
 
 private:
diff --git a/src/lib/language/moduleloader.cpp b/src/lib/language/moduleloader.cpp
index 041226316..56b8284e8 100644
--- a/src/lib/language/moduleloader.cpp
+++ b/src/lib/language/moduleloader.cpp
@@ -29,6 +29,7 @@
 
 #include "moduleloader.h"
 
+#include "builtindeclarations.h"
 #include "builtinvalue.h"
 #include "evaluator.h"
 #include "filecontext.h"
@@ -135,23 +136,36 @@ void ModuleLoader::handleProject(ModuleLoaderResult *loadResult, Item *item)
 
     foreach (Item *child, item->children()) {
         child->setScope(projectContext.scope);
-        if (child->typeName() == QLatin1String("Product"))
+        if (child->typeName() == QLatin1String("Product")) {
             handleProduct(&projectContext, child);
+        } else if (child->typeName() == QLatin1String("SubProject")) {
+            handleSubProject(&projectContext, child);
+        } else if (child->typeName() == QLatin1String("Project")) {
+            copyProperties(item, child);
+            handleProject(loadResult, child);
+        }
     }
 
     const QString projectFileDirPath = FileInfo::path(item->file()->filePath());
     const QStringList refs = toStringList(m_evaluator->property(item, "references"));
     foreach (const QString &filePath, refs) {
         const QString absReferencePath = FileInfo::resolvePath(projectFileDirPath, filePath);
-        Item *subprj = m_reader->readFile(absReferencePath);
-        if (subprj->typeName() != "Product")
-            throw Error(Tr::tr("%1 is not a product.").arg(subprj->typeName()), subprj->location());
-        subprj->setScope(projectContext.scope);
-        subprj->setParent(projectContext.item);
+        Item *subItem = m_reader->readFile(absReferencePath);
+        subItem->setScope(projectContext.scope);
+        subItem->setParent(projectContext.item);
         QList<Item *> projectChildren = projectContext.item->children();
-        projectChildren += subprj;
+        projectChildren += subItem;
         projectContext.item->setChildren(projectChildren);
-        handleProduct(&projectContext, subprj);
+        if (subItem->typeName() == "Product") {
+            handleProduct(&projectContext, subItem);
+        } else if (subItem->typeName() == "Project") {
+            copyProperties(item, subItem);
+            handleProject(loadResult, subItem);
+        } else {
+            throw Error(Tr::tr("The top-level item of a file in a \"references\" list must be "
+                               "a Product or a Project, but it is \"%1\".").arg(subItem->typeName()),
+                        subItem->location());
+        }
     }
 }
 
@@ -192,6 +206,59 @@ void ModuleLoader::handleProduct(ProjectContext *projectContext, Item *item)
     projectContext->result->productInfos.insert(item, productContext.info);
 }
 
+void ModuleLoader::handleSubProject(ModuleLoader::ProjectContext *projectContext, Item *item)
+{
+    if (m_logger.traceEnabled())
+        m_logger.qbsTrace() << "[MODLDR] handleSubProject " << item->file()->filePath();
+
+    Item *propertiesItem = 0;
+    foreach (Item * const subItem, item->children()) {
+        if (subItem->typeName() == QLatin1String("Properties")) {
+            propertiesItem = subItem;
+            break;
+        }
+    }
+
+    bool subProjectEnabled = true;
+    if (propertiesItem)
+        subProjectEnabled = checkItemCondition(propertiesItem);
+    if (!subProjectEnabled)
+        return;
+
+    const QString projectFileDirPath = FileInfo::path(item->file()->filePath());
+    QString subProjectFilePath = m_evaluator->property(item, "filePath").toString();
+    subProjectFilePath = FileInfo::resolvePath(projectFileDirPath, subProjectFilePath);
+    Item *loadedItem = m_reader->readFile(subProjectFilePath);
+    if (loadedItem->typeName() == QLatin1String("Product"))
+        loadedItem = wrapWithProject(loadedItem);
+    const bool inheritProperties
+            = m_evaluator->boolValue(item, QLatin1String("inheritProperties"), true);
+
+    if (inheritProperties)
+        copyProperties(item->parent(), loadedItem);
+    if (propertiesItem) {
+        const Item::PropertyMap &overriddenProperties = propertiesItem->properties();
+        for (Item::PropertyMap::ConstIterator it = overriddenProperties.constBegin();
+             it != overriddenProperties.constEnd(); ++it) {
+            loadedItem->setProperty(it.key(), overriddenProperties.value(it.key()));
+        }
+    }
+
+    if (loadedItem->typeName() != QLatin1String("Project")) {
+        Error error;
+        error.append(Tr::tr("Expected Project item, but encountered '%1'.")
+                     .arg(loadedItem->typeName()), loadedItem->location());
+        const ValuePtr &filePathProperty = item->properties().value(QLatin1String("filePath"));
+        error.append(Tr::tr("The problematic file was referenced from here."),
+                     filePathProperty->location());
+        throw error;
+    }
+
+    Item::addChild(item, loadedItem);
+    item->setScope(projectContext->scope);
+    handleProject(projectContext->result, loadedItem);
+}
+
 void ModuleLoader::createAdditionalModuleInstancesInProduct(ProductContext *productContext)
 {
     Item::Modules modulesToCheck;
@@ -723,27 +790,13 @@ void ModuleLoader::checkCancelation() const
 {
     if (m_progressObserver && m_progressObserver->canceled()) {
         throw Error(Tr::tr("Project resolving canceled for configuration %1.")
-                    .arg(ResolvedProject::deriveId(m_userProperties)));
+                    .arg(TopLevelProject::deriveId(m_userProperties)));
     }
 }
 
 bool ModuleLoader::checkItemCondition(Item *item)
 {
-    QScriptValue value = m_evaluator->property(item, QLatin1String("condition"));
-    if (!value.isValid() || value.isUndefined()) {
-        // Item doesn't have a condition binding. Handled as true.
-        return true;
-    }
-    if (Q_UNLIKELY(value.isError())) {
-        CodeLocation location;
-        ValuePtr prop = item->property("condition");
-        if (prop && prop->type() == Value::JSSourceValueType)
-            location = prop.staticCast<JSSourceValue>()->location();
-        Error e(Tr::tr("Error in condition."), location);
-        e.append(value.toString());
-        throw e;
-    }
-    return value.toBool();
+    return m_evaluator->boolValue(item, QLatin1String("condition"), true);
 }
 
 QStringList ModuleLoader::readExtraSearchPaths(Item *item)
@@ -755,6 +808,27 @@ QStringList ModuleLoader::readExtraSearchPaths(Item *item)
     return result;
 }
 
+void ModuleLoader::copyProperties(const Item *sourceProject, Item *targetProject)
+{
+    if (!sourceProject)
+        return;
+    const QList<PropertyDeclaration> &builtinProjectProperties
+            = m_reader->builtins()->declarationsForType(QLatin1String("Project"));
+    QSet<QString> builtinProjectPropertyNames;
+    foreach (const PropertyDeclaration &p, builtinProjectProperties)
+        builtinProjectPropertyNames << p.name;
+    for (Item::PropertyDeclarationMap::ConstIterator it
+         = sourceProject->propertyDeclarations().constBegin();
+         it != sourceProject->propertyDeclarations().constEnd(); ++it) {
+        if (builtinProjectPropertyNames.contains(it.key()))
+            continue; // Ignore built-ins.
+        if (targetProject->propertyDeclarations().contains(it.key()))
+            continue; // Ignore stuff the target project already has.
+        targetProject->setPropertyDeclaration(it.key(), it.value());
+        copyProperty(it.key(), sourceProject, targetProject);
+    }
+}
+
 Item *ModuleLoader::wrapWithProject(Item *item)
 {
     Item *prj = Item::create(item->pool());
diff --git a/src/lib/language/moduleloader.h b/src/lib/language/moduleloader.h
index 9a0075ba5..8ea9448fe 100644
--- a/src/lib/language/moduleloader.h
+++ b/src/lib/language/moduleloader.h
@@ -145,6 +145,7 @@ private:
 
     void handleProject(ModuleLoaderResult *loadResult, Item *item);
     void handleProduct(ProjectContext *projectContext, Item *item);
+    void handleSubProject(ProjectContext *projectContext, Item *item);
     void createAdditionalModuleInstancesInProduct(ProductContext *productContext);
     void handleGroup(ProductContext *productContext, Item *group);
     void handleArtifact(ProductContext *productContext, Item *item);
@@ -171,6 +172,7 @@ private:
     void checkCancelation() const;
     bool checkItemCondition(Item *item);
     QStringList readExtraSearchPaths(Item *item);
+    void copyProperties(const Item *sourceProject, Item *targetProject);
     static Item *wrapWithProject(Item *item);
     static QString findExistingModulePath(const QString &searchPath,
             const QStringList &moduleName);
diff --git a/src/lib/language/projectresolver.cpp b/src/lib/language/projectresolver.cpp
index 85d8df6bc..2444c62a8 100644
--- a/src/lib/language/projectresolver.cpp
+++ b/src/lib/language/projectresolver.cpp
@@ -33,7 +33,6 @@
 #include "builtindeclarations.h"
 #include "evaluator.h"
 #include "filecontext.h"
-#include "item.h"
 #include "moduleloader.h"
 #include "propertymapinternal.h"
 #include "scriptengine.h"
@@ -48,6 +47,7 @@
 
 #include <QFileInfo>
 #include <QDir>
+#include <QSet>
 #include <set>
 
 namespace qbs {
@@ -67,9 +67,8 @@ ProjectResolver::ProjectResolver(ModuleLoader *ldr, const BuiltinDeclarations *b
     , m_logger(logger)
     , m_engine(m_evaluator->engine())
     , m_progressObserver(0)
+    , m_builtinDeclarations(builtins)
 {
-    foreach (const PropertyDeclaration &pd, builtins->declarationsForType("Group"))
-        m_groupPropertyDeclarations += pd.name;
 }
 
 ProjectResolver::~ProjectResolver()
@@ -81,12 +80,12 @@ void ProjectResolver::setProgressObserver(ProgressObserver *observer)
     m_progressObserver = observer;
 }
 
-ResolvedProjectPtr ProjectResolver::resolve(ModuleLoaderResult &loadResult,
+TopLevelProjectPtr ProjectResolver::resolve(ModuleLoaderResult &loadResult,
                                             const QString &buildRoot,
                                             const QVariantMap &buildConfiguration,
                                             const QProcessEnvironment &environment)
 {
-    QBS_ASSERT(FileInfo::isAbsolute(buildRoot), return ResolvedProjectPtr());
+    QBS_ASSERT(FileInfo::isAbsolute(buildRoot), return TopLevelProjectPtr());
     if (m_logger.traceEnabled())
         m_logger.qbsTrace() << "[PR] resolving " << loadResult.root->file()->filePath();
 
@@ -95,64 +94,20 @@ ResolvedProjectPtr ProjectResolver::resolve(ModuleLoaderResult &loadResult,
     m_buildRoot = buildRoot;
     m_buildConfiguration = buildConfiguration;
     m_environment = environment;
-    m_projectContext = &projectContext;
     m_productContext = 0;
     m_moduleContext = 0;
-    resolveProject(loadResult.root);
-    m_projectContext = 0;
-    projectContext.project->usedEnvironment = m_engine->usedEnvironment();
-    projectContext.project->environment = m_environment;
-    return projectContext.project;
+    resolveTopLevelProject(loadResult.root, &projectContext);
+    return projectContext.project.staticCast<TopLevelProject>();
 }
 
 void ProjectResolver::checkCancelation() const
 {
     if (m_progressObserver && m_progressObserver->canceled()) {
         throw Error(Tr::tr("Project resolving canceled for configuration %1.")
-                    .arg(ResolvedProject::deriveId(m_buildConfiguration)));
+                    .arg(TopLevelProject::deriveId(m_buildConfiguration)));
     }
 }
 
-bool ProjectResolver::boolValue(const Item *item, const QString &name, bool defaultValue) const
-{
-    QScriptValue v = m_evaluator->property(item, name);
-    if (Q_UNLIKELY(v.isError())) {
-        ValuePtr value = item->property(name);
-        throw Error(v.toString(), value ? value->location() : CodeLocation());
-    }
-    if (!v.isValid() || v.isUndefined())
-        return defaultValue;
-    return v.toBool();
-}
-
-FileTags ProjectResolver::fileTagsValue(const Item *item, const QString &name) const
-{
-    return FileTags::fromStringList(stringListValue(item, name));
-}
-
-QString ProjectResolver::stringValue(const Item *item, const QString &name,
-                                     const QString &defaultValue) const
-{
-    QScriptValue v = m_evaluator->property(item, name);
-    if (Q_UNLIKELY(v.isError())) {
-        ValuePtr value = item->property(name);
-        throw Error(v.toString(), value ? value->location() : CodeLocation());
-    }
-    if (!v.isValid() || v.isUndefined())
-        return defaultValue;
-    return v.toString();
-}
-
-QStringList ProjectResolver::stringListValue(const Item *item, const QString &name) const
-{
-    QScriptValue v = m_evaluator->property(item, name);
-    if (Q_UNLIKELY(v.isError())) {
-        ValuePtr value = item->property(name);
-        throw Error(v.toString(), value ? value->location() : CodeLocation());
-    }
-    return toStringList(v);
-}
-
 QString ProjectResolver::verbatimValue(const ValueConstPtr &value) const
 {
     QString result;
@@ -168,22 +123,66 @@ QString ProjectResolver::verbatimValue(Item *item, const QString &name) const
     return verbatimValue(item->property(name));
 }
 
-void ProjectResolver::ignoreItem(Item *item)
+void ProjectResolver::ignoreItem(Item *item, ProjectContext *projectContext)
 {
     Q_UNUSED(item);
+    Q_UNUSED(projectContext);
 }
 
-void ProjectResolver::resolveProject(Item *item)
+static void makeSubProjectNamesUniqe(const ResolvedProjectPtr &parentProject)
 {
-    checkCancelation();
+    QSet<QString> subProjectNames;
+    QSet<ResolvedProjectPtr> projectsInNeedOfNameChange;
+    foreach (const ResolvedProjectPtr &p, parentProject->subProjects) {
+        if (subProjectNames.contains(p->name))
+            projectsInNeedOfNameChange << p;
+        else
+            subProjectNames << p->name;
+        makeSubProjectNamesUniqe(p);
+    }
+    while (!projectsInNeedOfNameChange.isEmpty()) {
+        QSet<ResolvedProjectPtr>::Iterator it = projectsInNeedOfNameChange.begin();
+        while (it != projectsInNeedOfNameChange.end()) {
+            const ResolvedProjectPtr p = *it;
+            p->name += QLatin1Char('_');
+            if (!subProjectNames.contains(p->name)) {
+                subProjectNames << p->name;
+                it = projectsInNeedOfNameChange.erase(it);
+            } else {
+                ++it;
+            }
+        }
+    }
+}
 
-    ResolvedProjectPtr project = ResolvedProject::create();
-    m_projectContext->project = project;
-    m_projectContext->dummyModule = ResolvedModule::create();
-    m_projectContext->dummyModule->jsImports = item->file()->jsImports();
-    project->location = item->location();
+void ProjectResolver::resolveTopLevelProject(Item *item, ProjectContext *projectContext)
+{
+    const TopLevelProjectPtr project = TopLevelProject::create();
     project->setBuildConfiguration(m_buildConfiguration);
-    project->buildDirectory = ResolvedProject::deriveBuildDirectory(m_buildRoot, project->id());
+    project->buildDirectory = TopLevelProject::deriveBuildDirectory(m_buildRoot, project->id());
+    projectContext->project = project;
+    resolveProject(item, projectContext);
+    project->usedEnvironment = m_engine->usedEnvironment();
+    project->environment = m_environment;
+    makeSubProjectNamesUniqe(project);
+    resolveProductDependencies(projectContext);
+}
+
+void ProjectResolver::resolveProject(Item *item, ProjectContext *projectContext)
+{
+    checkCancelation();
+
+    projectContext->project->name = m_evaluator->stringValue(item, QLatin1String("name"));
+    projectContext->project->location = item->location();
+    if (projectContext->project->name.isEmpty())
+        projectContext->project->name = FileInfo::baseName(item->location().fileName()); // FIXME: Must also be changed in item?
+    projectContext->project->enabled
+            = m_evaluator->boolValue(item, QLatin1String("condition"), true);
+    if (!projectContext->project->enabled)
+        return;
+
+    projectContext->dummyModule = ResolvedModule::create();
+    projectContext->dummyModule->jsImports = item->file()->jsImports();
 
     m_evaluator->engine()->setEnvironment(m_environment);
 
@@ -197,32 +196,36 @@ void ProjectResolver::resolveProject(Item *item)
         QBS_ASSERT(v && v->type() != Value::ItemValueType, continue);
         projectProperties.insert(it.key(), m_evaluator->property(item, it.key()).toVariant());
     }
-    project->setProjectProperties(projectProperties);
+    projectContext->project->setProjectProperties(projectProperties);
 
     ItemFuncMap mapping;
+    mapping["Project"] = &ProjectResolver::resolveProject;
+    mapping["SubProject"] = &ProjectResolver::resolveSubProject;
     mapping["Product"] = &ProjectResolver::resolveProduct;
     mapping["FileTagger"] = &ProjectResolver::resolveFileTagger;
     mapping["Rule"] = &ProjectResolver::resolveRule;
 
-    if (m_progressObserver)
-        m_progressObserver->setMaximum(item->children().count() + 2);
     foreach (Item *child, item->children()) {
-        callItemFunction(mapping, child);
+        callItemFunction(mapping, child, projectContext);
         if (m_progressObserver)
             m_progressObserver->incrementProgressValue();
     }
 
-    foreach (const ResolvedProductPtr &product, project->products)
-        postProcess(product);
-    if (m_progressObserver)
-        m_progressObserver->incrementProgressValue();
+    foreach (const ResolvedProductPtr &product, projectContext->project->products)
+        postProcess(product, projectContext);
+}
+
+void ProjectResolver::resolveSubProject(Item *item, ProjectResolver::ProjectContext *projectContext)
+{
+    ProjectContext subProjectContext = createProjectContext(projectContext);
 
-    resolveProductDependencies();
-    if (m_progressObserver)
-        m_progressObserver->incrementProgressValue();
+    foreach (Item * const subItem, item->children()) {
+        if (subItem->typeName() == QLatin1String("Project"))
+            resolveProject(subItem, &subProjectContext);
+    }
 }
 
-void ProjectResolver::resolveProduct(Item *item)
+void ProjectResolver::resolveProduct(Item *item, ProjectContext *projectContext)
 {
     checkCancelation();
     ProductContext productContext;
@@ -231,28 +234,30 @@ void ProjectResolver::resolveProduct(Item *item)
     const QString productSourceDirectory = QFileInfo(item->file()->filePath()).absolutePath();
     item->setProperty(QLatin1String("sourceDirectory"),
                       VariantValue::create(productSourceDirectory));
-    item->setProperty(QLatin1String("buildDirectory"),
-                      VariantValue::create(m_projectContext->project->buildDirectory));
+    item->setProperty(QLatin1String("buildDirectory"), VariantValue::create(projectContext
+            ->project->topLevelProject()->buildDirectory));
     ResolvedProductPtr product = ResolvedProduct::create();
-    m_projectContext->productItemMap.insert(product, item);
-    m_projectContext->project->products += product;
+    product->project = projectContext->project;
+    m_productItemMap.insert(product, item);
+    projectContext->project->products += product;
     productContext.product = product;
-    product->name = stringValue(item, QLatin1String("name"));
+    product->name = m_evaluator->stringValue(item, QLatin1String("name"));
     if (product->name.isEmpty()) {
         product->name = FileInfo::completeBaseName(item->file()->filePath());
         item->setProperty("name", VariantValue::create(product->name));
     }
     m_logger.qbsTrace() << "[PR] resolveProduct " << product->name;
     ModuleLoader::overrideItemProperties(item, product->name, m_buildConfiguration);
-    m_projectContext->productsByName.insert(product->name, product);
-    product->enabled = boolValue(item, QLatin1String("condition"), true);
-    product->additionalFileTags = fileTagsValue(item, QLatin1String("additionalFileTags"));
-    product->fileTags = fileTagsValue(item, QLatin1String("type"));
-    product->targetName = stringValue(item, QLatin1String("targetName"));
+    m_productsByName.insert(product->name, product);
+    product->enabled = m_evaluator->boolValue(item, QLatin1String("condition"), true);
+    product->additionalFileTags
+            = m_evaluator->fileTagsValue(item, QLatin1String("additionalFileTags"));
+    product->fileTags = m_evaluator->fileTagsValue(item, QLatin1String("type"));
+    product->targetName = m_evaluator->stringValue(item, QLatin1String("targetName"));
     product->sourceDirectory = productSourceDirectory;
-    product->destinationDirectory = stringValue(item, QLatin1String("destinationDirectory"));
+    product->destinationDirectory
+            = m_evaluator->stringValue(item, QLatin1String("destinationDirectory"));
     product->location = item->location();
-    product->project = m_projectContext->project;
     product->properties = PropertyMapInternal::create();
     product->properties->setValue(createProductConfig());
     ModuleProperties::init(m_evaluator->scriptValue(item), product);
@@ -283,15 +288,16 @@ void ProjectResolver::resolveProduct(Item *item)
     mapping["Probe"] = &ProjectResolver::ignoreItem;
 
     foreach (Item *child, subItems)
-        callItemFunction(mapping, child);
+        callItemFunction(mapping, child, projectContext);
 
     foreach (const Item::Module &module, item->modules())
-        resolveModule(module.name, module.item);
+        resolveModule(module.name, module.item, projectContext);
 
     m_productContext = 0;
 }
 
-void ProjectResolver::resolveModule(const QStringList &moduleName, Item *item)
+void ProjectResolver::resolveModule(const QStringList &moduleName, Item *item,
+                                    ProjectContext *projectContext)
 {
     checkCancelation();
     ModuleContext moduleContext;
@@ -304,7 +310,7 @@ void ProjectResolver::resolveModule(const QStringList &moduleName, Item *item)
     module->setupRunEnvironmentScript = verbatimValue(item, "setupRunEnvironment");
 
     m_productContext->product->additionalFileTags
-            += fileTagsValue(item, "additionalProductFileTags");
+            += m_evaluator->fileTagsValue(item, "additionalProductFileTags");
 
     // TODO: instead of jsImports, we need the file context for both setup scripts separately.
     //       ATM the setup scripts must be in the first file of the inheritance chain.
@@ -323,7 +329,7 @@ void ProjectResolver::resolveModule(const QStringList &moduleName, Item *item)
     mapping["Depends"] = &ProjectResolver::ignoreItem;
     mapping["Probe"] = &ProjectResolver::ignoreItem;
     foreach (Item *child, item->children())
-        callItemFunction(mapping, child);
+        callItemFunction(mapping, child, projectContext);
 
     m_moduleContext = 0;
 }
@@ -360,8 +366,9 @@ static bool isSomeModulePropertySet(Item *group)
     return false;
 }
 
-void ProjectResolver::resolveGroup(Item *item)
+void ProjectResolver::resolveGroup(Item *item, ProjectContext *projectContext)
 {
+    Q_UNUSED(projectContext);
     checkCancelation();
     PropertyMapPtr properties = m_productContext->product->properties;
     if (isSomeModulePropertySet(item)) {
@@ -369,8 +376,9 @@ void ProjectResolver::resolveGroup(Item *item)
         properties->setValue(evaluateModuleValues(item));
     }
 
-    QStringList files = stringListValue(item, QLatin1String("files"));
-    const QStringList fileTagsFilter = stringListValue(item, QLatin1String("fileTagsFilter"));
+    QStringList files = m_evaluator->stringListValue(item, QLatin1String("files"));
+    const QStringList fileTagsFilter
+            = m_evaluator->stringListValue(item, QLatin1String("fileTagsFilter"));
     if (!fileTagsFilter.isEmpty()) {
         if (Q_UNLIKELY(!files.isEmpty()))
             throw Error(Tr::tr("Group.files and Group.fileTagsFilters are exclusive."),
@@ -395,21 +403,21 @@ void ProjectResolver::resolveGroup(Item *item)
         if (FileInfo::isPattern(files[i]))
             patterns.append(files.takeAt(i));
     }
-    prefix = stringValue(item, QLatin1String("prefix"));
+    prefix = m_evaluator->stringValue(item, QLatin1String("prefix"));
     if (!prefix.isEmpty()) {
         for (int i = files.count(); --i >= 0;)
                 files[i].prepend(prefix);
     }
-    FileTags fileTags = fileTagsValue(item, QLatin1String("fileTags"));
-    bool overrideTags = boolValue(item, QLatin1String("overrideTags"), true);
+    FileTags fileTags = m_evaluator->fileTagsValue(item, QLatin1String("fileTags"));
+    bool overrideTags = m_evaluator->boolValue(item, QLatin1String("overrideTags"), true);
 
     GroupPtr group = ResolvedGroup::create();
     group->location = item->location();
-    group->enabled = boolValue(item, QLatin1String("condition"), true);
+    group->enabled = m_evaluator->boolValue(item, QLatin1String("condition"), true);
 
     if (!patterns.isEmpty()) {
         SourceWildCards::Ptr wildcards = SourceWildCards::create();
-        wildcards->excludePatterns = stringListValue(item, "excludeFiles");
+        wildcards->excludePatterns = m_evaluator->stringListValue(item, "excludeFiles");
         wildcards->prefix = prefix;
         wildcards->patterns = patterns;
         QSet<QString> files = wildcards->expandPatterns(group, m_productContext->product->sourceDirectory);
@@ -432,7 +440,7 @@ void ProjectResolver::resolveGroup(Item *item)
     if (!fileError.entries().isEmpty())
         throw Error(fileError);
 
-    group->name = stringValue(item, "name");
+    group->name = m_evaluator->stringValue(item, "name");
     if (group->name.isEmpty())
         group->name = Tr::tr("Group %1").arg(m_productContext->product->groups.count());
     group->properties = properties;
@@ -451,11 +459,11 @@ static QString sourceCodeAsFunction(const JSSourceValueConstPtr &value)
     }
 }
 
-void ProjectResolver::resolveRule(Item *item)
+void ProjectResolver::resolveRule(Item *item, ProjectContext *projectContext)
 {
     checkCancelation();
 
-    if (!boolValue(item, QLatin1String("condition"), true))
+    if (!m_evaluator->boolValue(item, QLatin1String("condition"), true))
         return;
 
     RulePtr rule = Rule::create();
@@ -484,15 +492,15 @@ void ProjectResolver::resolveRule(Item *item)
 
     rule->jsImports = item->file()->jsImports();
     rule->script = prepareScript;
-    rule->multiplex = boolValue(item, "multiplex", false);
-    rule->inputs = fileTagsValue(item, "inputs");
-    rule->usings = fileTagsValue(item, "usings");
-    rule->explicitlyDependsOn = fileTagsValue(item, "explicitlyDependsOn");
-    rule->module = m_moduleContext ? m_moduleContext->module : m_projectContext->dummyModule;
+    rule->multiplex = m_evaluator->boolValue(item, "multiplex", false);
+    rule->inputs = m_evaluator->fileTagsValue(item, "inputs");
+    rule->usings = m_evaluator->fileTagsValue(item, "usings");
+    rule->explicitlyDependsOn = m_evaluator->fileTagsValue(item, "explicitlyDependsOn");
+    rule->module = m_moduleContext ? m_moduleContext->module : projectContext->dummyModule;
     if (m_productContext)
         m_productContext->product->rules += rule;
     else
-        m_projectContext->rules += rule;
+        projectContext->rules += rule;
 }
 
 class StringListLess
@@ -524,8 +532,8 @@ void ProjectResolver::resolveRuleArtifact(const RulePtr &rule, Item *item,
     RuleArtifactPtr artifact = RuleArtifact::create();
     rule->artifacts += artifact;
     artifact->fileName = verbatimValue(item, "fileName");
-    artifact->fileTags = fileTagsValue(item, "fileTags");
-    artifact->alwaysUpdated = boolValue(item, "alwaysUpdated", true);
+    artifact->fileTags = m_evaluator->fileTagsValue(item, "fileTags");
+    artifact->alwaysUpdated = m_evaluator->boolValue(item, "alwaysUpdated", true);
     if (artifact->alwaysUpdated)
         *hasAlwaysUpdatedArtifact = true;
 
@@ -571,27 +579,27 @@ void ProjectResolver::resolveRuleArtifactBinding(const RuleArtifactPtr &ruleArti
     }
 }
 
-void ProjectResolver::resolveFileTagger(Item *item)
+void ProjectResolver::resolveFileTagger(Item *item, ProjectContext *projectContext)
 {
     checkCancelation();
     QSet<FileTaggerConstPtr> &fileTaggers = m_productContext
-            ? m_productContext->product->fileTaggers : m_projectContext->fileTaggers;
-    fileTaggers += FileTagger::create(QRegExp(stringValue(item,"pattern")),
-            fileTagsValue(item, "fileTags"));
+            ? m_productContext->product->fileTaggers : projectContext->fileTaggers;
+    fileTaggers += FileTagger::create(QRegExp(m_evaluator->stringValue(item,"pattern")),
+            m_evaluator->fileTagsValue(item, "fileTags"));
 }
 
-void ProjectResolver::resolveTransformer(Item *item)
+void ProjectResolver::resolveTransformer(Item *item, ProjectContext *projectContext)
 {
     checkCancelation();
-    if (!boolValue(item, "condition", true)) {
+    if (!m_evaluator->boolValue(item, "condition", true)) {
         m_logger.qbsTrace() << "[PR] transformer condition is false";
         return;
     }
 
     ResolvedTransformer::Ptr rtrafo = ResolvedTransformer::create();
-    rtrafo->module = m_moduleContext ? m_moduleContext->module : m_projectContext->dummyModule;
+    rtrafo->module = m_moduleContext ? m_moduleContext->module : projectContext->dummyModule;
     rtrafo->jsImports = item->file()->jsImports();
-    rtrafo->inputs = stringListValue(item, "inputs");
+    rtrafo->inputs = m_evaluator->stringListValue(item, "inputs");
     for (int i = 0; i < rtrafo->inputs.count(); ++i)
         rtrafo->inputs[i] = FileInfo::resolvePath(m_productContext->product->sourceDirectory, rtrafo->inputs.at(i));
     const PrepareScriptPtr transform = PrepareScript::create();
@@ -605,12 +613,12 @@ void ProjectResolver::resolveTransformer(Item *item)
             throw Error(Tr::tr("Transformer: wrong child type '%0'.").arg(child->typeName()));
         SourceArtifactPtr artifact = SourceArtifact::create();
         artifact->properties = m_productContext->product->properties;
-        QString fileName = stringValue(child, "fileName");
+        QString fileName = m_evaluator->stringValue(child, "fileName");
         if (Q_UNLIKELY(fileName.isEmpty()))
             throw Error(Tr::tr("Artifact fileName must not be empty."));
-        artifact->absoluteFilePath = FileInfo::resolvePath(m_productContext->product->project->buildDirectory,
+        artifact->absoluteFilePath = FileInfo::resolvePath(m_productContext->product->topLevelProject()->buildDirectory,
                                                            fileName);
-        artifact->fileTags = fileTagsValue(child, "fileTags");
+        artifact->fileTags = m_evaluator->fileTagsValue(child, "fileTags");
         if (artifact->fileTags.isEmpty())
             artifact->fileTags.insert(unknownFileTag());
         rtrafo->outputs += artifact;
@@ -619,11 +627,12 @@ void ProjectResolver::resolveTransformer(Item *item)
     m_productContext->product->transformers += rtrafo;
 }
 
-void ProjectResolver::resolveExport(Item *item)
+void ProjectResolver::resolveExport(Item *item, ProjectContext *projectContext)
 {
+    Q_UNUSED(projectContext);
     checkCancelation();
     const QString &productName = m_productContext->product->name;
-    m_projectContext->exports[productName] = evaluateModuleValues(item);
+    m_exports[productName] = evaluateModuleValues(item);
 }
 
 static void insertExportedConfig(const QString &usedProductName,
@@ -655,26 +664,27 @@ static void addUsedProducts(ModuleLoaderResult::ProductInfo *productInfo,
     *productsAdded = (oldCount != productInfo->usedProducts.count());
 }
 
-void ProjectResolver::resolveProductDependencies()
+void ProjectResolver::resolveProductDependencies(ProjectContext *projectContext)
 {
     // Collect product dependencies from Export items.
     bool productDependenciesAdded;
+    QList<ResolvedProductPtr> allProducts = projectContext->project->allProducts();
     do {
         productDependenciesAdded = false;
-        foreach (ResolvedProductPtr rproduct, m_projectContext->project->products) {
-            Item *productItem = m_projectContext->productItemMap.value(rproduct);
+        foreach (const ResolvedProductPtr &rproduct, allProducts) {
+            Item *productItem = m_productItemMap.value(rproduct);
             ModuleLoaderResult::ProductInfo &productInfo
-                    = m_projectContext->loadResult->productInfos[productItem];
+                    = projectContext->loadResult->productInfos[productItem];
             foreach (const ModuleLoaderResult::ProductInfo::Dependency &dependency,
                         productInfo.usedProducts) {
                 ResolvedProductPtr usedProduct
-                        = m_projectContext->productsByName.value(dependency.name);
+                        = m_productsByName.value(dependency.name);
                 if (Q_UNLIKELY(!usedProduct))
                     throw Error(Tr::tr("Product dependency '%1' not found.").arg(dependency.name),
                                 productItem->location());
-                Item *usedProductItem = m_projectContext->productItemMap.value(usedProduct);
+                Item *usedProductItem = m_productItemMap.value(usedProduct);
                 const ModuleLoaderResult::ProductInfo usedProductInfo
-                        = m_projectContext->loadResult->productInfos.value(usedProductItem);
+                        = projectContext->loadResult->productInfos.value(usedProductItem);
                 bool added;
                 addUsedProducts(&productInfo, usedProductInfo, &added);
                 if (added)
@@ -684,21 +694,19 @@ void ProjectResolver::resolveProductDependencies()
     } while (productDependenciesAdded);
 
     // Resolve all inter-product dependencies.
-    foreach (ResolvedProductPtr rproduct, m_projectContext->project->products) {
-        Item *productItem = m_projectContext->productItemMap.value(rproduct);
+    foreach (const ResolvedProductPtr &rproduct, allProducts) {
+        Item *productItem = m_productItemMap.value(rproduct);
         foreach (const ModuleLoaderResult::ProductInfo::Dependency &dependency,
-                 m_projectContext->loadResult->productInfos.value(productItem).usedProducts) {
+                 projectContext->loadResult->productInfos.value(productItem).usedProducts) {
             const QString &usedProductName = dependency.name;
-            ResolvedProductPtr usedProduct
-                    = m_projectContext->productsByName.value(usedProductName);
+            ResolvedProductPtr usedProduct = m_productsByName.value(usedProductName);
             if (Q_UNLIKELY(!usedProduct))
                 throw Error(Tr::tr("Product dependency '%1' not found.").arg(usedProductName),
                             productItem->location());
             rproduct->dependencies.insert(usedProduct);
 
             // insert the configuration of the Export item into the product's configuration
-            const QVariantMap exportedConfig
-                    = m_projectContext->exports.value(usedProductName);
+            const QVariantMap exportedConfig = m_exports.value(usedProductName);
             if (exportedConfig.isEmpty())
                 continue;
 
@@ -714,10 +722,11 @@ void ProjectResolver::resolveProductDependencies()
     }
 }
 
-void ProjectResolver::postProcess(const ResolvedProductPtr &product) const
+void ProjectResolver::postProcess(const ResolvedProductPtr &product,
+                                  ProjectContext *projectContext) const
 {
-    product->fileTaggers += m_projectContext->fileTaggers;
-    foreach (const RulePtr &rule, m_projectContext->rules)
+    product->fileTaggers += projectContext->fileTaggers;
+    foreach (const RulePtr &rule, projectContext->rules)
         product->rules += rule;
     applyFileTaggers(product);
 }
@@ -855,8 +864,8 @@ QStringList ProjectResolver::convertPathListProperty(const QStringList &paths,
     return result;
 }
 
-void ProjectResolver::callItemFunction(const ItemFuncMap &mappings,
-                                       Item *item)
+void ProjectResolver::callItemFunction(const ItemFuncMap &mappings, Item *item,
+                                       ProjectContext *projectContext)
 {
     const QByteArray typeName = item->typeName().toLocal8Bit();
     ItemFuncPtr f = mappings.value(typeName);
@@ -864,7 +873,22 @@ void ProjectResolver::callItemFunction(const ItemFuncMap &mappings,
         const QString msg = Tr::tr("Unexpected item type '%1'.");
         throw Error(msg.arg(item->typeName()), item->location());
     }
-    (this->*f)(item);
+    if (typeName == "Project") {
+        ProjectContext subProjectContext = createProjectContext(projectContext);
+        (this->*f)(item, &subProjectContext);
+    } else {
+        (this->*f)(item, projectContext);
+    }
+}
+
+ProjectResolver::ProjectContext ProjectResolver::createProjectContext(ProjectContext *parentProjectContext) const
+{
+    ProjectContext subProjectContext;
+    subProjectContext.project = ResolvedProject::create();
+    parentProjectContext->project->subProjects += subProjectContext.project;
+    subProjectContext.project->parentProject = parentProjectContext->project;
+    subProjectContext.loadResult = parentProjectContext->loadResult;
+    return subProjectContext;
 }
 
 } // namespace Internal
diff --git a/src/lib/language/projectresolver.h b/src/lib/language/projectresolver.h
index bf4350ceb..dacc839ed 100644
--- a/src/lib/language/projectresolver.h
+++ b/src/lib/language/projectresolver.h
@@ -32,6 +32,7 @@
 
 #include "evaluator.h"
 #include "filetags.h"
+#include "item.h"
 #include "language.h"
 #include <logging/logger.h>
 
@@ -56,7 +57,7 @@ public:
     ~ProjectResolver();
 
     void setProgressObserver(ProgressObserver *observer);
-    ResolvedProjectPtr resolve(ModuleLoaderResult &loadResult, const QString &buildRoot,
+    TopLevelProjectPtr resolve(ModuleLoaderResult &loadResult, const QString &buildRoot,
                                const QVariantMap &buildConfiguration,
                                const QProcessEnvironment &environment);
 
@@ -68,9 +69,6 @@ private:
         ModuleLoaderResult *loadResult;
         QList<RulePtr> rules;
         ResolvedModulePtr dummyModule;
-        QMap<QString, ResolvedProductPtr> productsByName;
-        QHash<ResolvedProductPtr, Item *> productItemMap;
-        QMap<QString, QVariantMap> exports;
     };
 
     struct ProductContext
@@ -85,27 +83,25 @@ private:
     };
 
     void checkCancelation() const;
-    bool boolValue(const Item *item, const QString &name, bool defaultValue = false) const;
-    FileTags fileTagsValue(const Item *item, const QString &name) const;
-    QString stringValue(const Item *item, const QString &name, const QString &defaultValue = QString()) const;
-    QStringList stringListValue(const Item *item, const QString &name) const;
     QString verbatimValue(const ValueConstPtr &value) const;
     QString verbatimValue(Item *item, const QString &name) const;
-    void ignoreItem(Item *item);
-    void resolveProject(Item *item);
-    void resolveProduct(Item *item);
-    void resolveModule(const QStringList &moduleName, Item *item);
-    void resolveGroup(Item *item);
-    void resolveRule(Item *item);
+    void ignoreItem(Item *item, ProjectContext *projectContext);
+    void resolveTopLevelProject(Item *item, ProjectContext *projectContext);
+    void resolveProject(Item *item, ProjectContext *projectContext);
+    void resolveSubProject(Item *item, ProjectContext *projectContext);
+    void resolveProduct(Item *item, ProjectContext *projectContext);
+    void resolveModule(const QStringList &moduleName, Item *item, ProjectContext *projectContext);
+    void resolveGroup(Item *item, ProjectContext *projectContext);
+    void resolveRule(Item *item, ProjectContext *projectContext);
     void resolveRuleArtifact(const RulePtr &rule, Item *item, bool *hasAlwaysUpdatedArtifact);
     static void resolveRuleArtifactBinding(const RuleArtifactPtr &ruleArtifact, Item *item,
                                            const QStringList &namePrefix,
                                            StringListSet *seenBindings);
-    void resolveFileTagger(Item *item);
-    void resolveTransformer(Item *item);
-    void resolveExport(Item *item);
-    void resolveProductDependencies();
-    void postProcess(const ResolvedProductPtr &product) const;
+    void resolveFileTagger(Item *item, ProjectContext *projectContext);
+    void resolveTransformer(Item *item, ProjectContext *projectContext);
+    void resolveExport(Item *item, ProjectContext *projectContext);
+    void resolveProductDependencies(ProjectContext *projectContext);
+    void postProcess(const ResolvedProductPtr &product, ProjectContext *projectContext) const;
     void applyFileTaggers(const ResolvedProductPtr &product) const;
     void applyFileTaggers(const SourceArtifactPtr &artifact,
                           const ResolvedProductConstPtr &product) const;
@@ -117,6 +113,7 @@ private:
     QVariantMap createProductConfig() const;
     QString convertPathProperty(const QString &path, const QString &dirPath) const;
     QStringList convertPathListProperty(const QStringList &paths, const QString &dirPath) const;
+    ProjectContext createProjectContext(ProjectContext *parentProjectContext) const;
 
     Evaluator *m_evaluator;
     Logger m_logger;
@@ -124,15 +121,17 @@ private:
     ProgressObserver *m_progressObserver;
     QString m_buildRoot;
     QVariantMap m_buildConfiguration;
-    ProjectContext *m_projectContext;
     ProductContext *m_productContext;
     ModuleContext *m_moduleContext;
-    QSet<QString> m_groupPropertyDeclarations;
     QProcessEnvironment m_environment;
+    QMap<QString, ResolvedProductPtr> m_productsByName;
+    QHash<ResolvedProductPtr, Item *> m_productItemMap;
+    QMap<QString, QVariantMap> m_exports;
+    const BuiltinDeclarations * const m_builtinDeclarations;
 
-    typedef void (ProjectResolver::*ItemFuncPtr)(Item *item);
+    typedef void (ProjectResolver::*ItemFuncPtr)(Item *item, ProjectContext *projectContext);
     typedef QMap<QByteArray, ItemFuncPtr> ItemFuncMap;
-    void callItemFunction(const ItemFuncMap &mappings, Item *item);
+    void callItemFunction(const ItemFuncMap &mappings, Item *item, ProjectContext *projectContext);
 };
 
 } // namespace Internal
diff --git a/src/lib/language/tst_language.cpp b/src/lib/language/tst_language.cpp
index 23a01d062..49f5ade73 100644
--- a/src/lib/language/tst_language.cpp
+++ b/src/lib/language/tst_language.cpp
@@ -314,7 +314,7 @@ void TestLanguage::exports()
     bool exceptionCaught = false;
     try {
         defaultParameters.setProjectFilePath(testProject("exports.qbs"));
-        ResolvedProjectPtr project = loader->loadProject(defaultParameters);
+        TopLevelProjectPtr project = loader->loadProject(defaultParameters);
         QVERIFY(project);
         QHash<QString, ResolvedProductPtr> products = productsFromProject(project);
         QCOMPARE(products.count(), 8);
@@ -431,7 +431,7 @@ void TestLanguage::groupName()
     bool exceptionCaught = false;
     try {
         defaultParameters.setProjectFilePath(testProject("groupname.qbs"));
-        ResolvedProjectPtr project = loader->loadProject(defaultParameters);
+        TopLevelProjectPtr project = loader->loadProject(defaultParameters);
         QVERIFY(project);
         QHash<QString, ResolvedProductPtr> products = productsFromProject(project);
         QCOMPARE(products.count(), 2);
@@ -575,7 +575,7 @@ void TestLanguage::idUsage()
     bool exceptionCaught = false;
     try {
         defaultParameters.setProjectFilePath(testProject("idusage.qbs"));
-        ResolvedProjectPtr project = loader->loadProject(defaultParameters);
+        TopLevelProjectPtr project = loader->loadProject(defaultParameters);
         QVERIFY(project);
         QHash<QString, ResolvedProductPtr> products = productsFromProject(project);
         QCOMPARE(products.count(), 3);
@@ -686,7 +686,7 @@ void TestLanguage::jsImportUsedInMultipleScopes()
         SetupProjectParameters params = defaultParameters;
         params.setProjectFilePath(testProject("jsimportsinmultiplescopes.qbs"));
         params.setBuildConfiguration(customBuildConfig);
-        ResolvedProjectPtr project = loader->loadProject(params);
+        TopLevelProjectPtr project = loader->loadProject(params);
         QVERIFY(project);
         QHash<QString, ResolvedProductPtr> products = productsFromProject(project);
         QCOMPARE(products.count(), 1);
@@ -755,7 +755,7 @@ void TestLanguage::moduleScope()
     bool exceptionCaught = false;
     try {
         defaultParameters.setProjectFilePath(testProject("modulescope.qbs"));
-        ResolvedProjectPtr project = loader->loadProject(defaultParameters);
+        TopLevelProjectPtr project = loader->loadProject(defaultParameters);
         QVERIFY(project);
         QHash<QString, ResolvedProductPtr> products = productsFromProject(project);
         QCOMPARE(products.count(), 1);
@@ -827,7 +827,7 @@ void TestLanguage::outerInGroup()
     bool exceptionCaught = false;
     try {
         defaultParameters.setProjectFilePath(testProject("outerInGroup.qbs"));
-        ResolvedProjectPtr project = loader->loadProject(defaultParameters);
+        TopLevelProjectPtr project = loader->loadProject(defaultParameters);
         QVERIFY(project);
         QHash<QString, ResolvedProductPtr> products = productsFromProject(project);
         QCOMPARE(products.count(), 1);
@@ -892,7 +892,7 @@ void TestLanguage::productConditions()
     bool exceptionCaught = false;
     try {
         defaultParameters.setProjectFilePath(testProject("productconditions.qbs"));
-        ResolvedProjectPtr project = loader->loadProject(defaultParameters);
+        TopLevelProjectPtr project = loader->loadProject(defaultParameters);
         QVERIFY(project);
         QHash<QString, ResolvedProductPtr> products = productsFromProject(project);
         QCOMPARE(products.count(), 4);
diff --git a/src/lib/language/tst_language.h b/src/lib/language/tst_language.h
index 3784ccba0..e820c3224 100644
--- a/src/lib/language/tst_language.h
+++ b/src/lib/language/tst_language.h
@@ -52,7 +52,7 @@ private:
     Logger m_logger;
     ScriptEngine *m_engine;
     Loader *loader;
-    ResolvedProjectPtr project;
+    TopLevelProjectPtr project;
     SetupProjectParameters defaultParameters;
     const QString m_wildcardsTestDirPath;
 
diff --git a/src/lib/tools/persistence.cpp b/src/lib/tools/persistence.cpp
index 4a22e2eaa..1e93e0950 100644
--- a/src/lib/tools/persistence.cpp
+++ b/src/lib/tools/persistence.cpp
@@ -39,7 +39,7 @@
 namespace qbs {
 namespace Internal {
 
-static const char QBS_PERSISTENCE_MAGIC[] = "QBSPERSISTENCE-40";
+static const char QBS_PERSISTENCE_MAGIC[] = "QBSPERSISTENCE-41";
 
 PersistentPool::PersistentPool(const Logger &logger) : m_logger(logger)
 {
diff --git a/src/lib/tools/weakpointer.h b/src/lib/tools/weakpointer.h
index 2b6e820e7..a8a82a5dd 100644
--- a/src/lib/tools/weakpointer.h
+++ b/src/lib/tools/weakpointer.h
@@ -39,6 +39,8 @@ template<typename T> class WeakPointer : public QWeakPointer<T>
 public:
     WeakPointer() : QWeakPointer<T>() {}
     WeakPointer(const QSharedPointer<T> &sharedPointer) : QWeakPointer<T>(sharedPointer) {}
+    template <class X> WeakPointer(const QSharedPointer<X> &sp) : QWeakPointer<T>(sp) { }
+
 
     operator T*() const { return checkedData(); }
     T *operator->() const { return checkedData(); }
author	Christian Kandeler <christian.kandeler@digia.com>	2013-06-06 10:06:30 +0200
committer	Joerg Bornemann <joerg.bornemann@digia.com>	2013-06-17 14:23:19 +0200
commit	ab60f6e4c489ace089785c002d75018ac6a31e30 (patch)
tree	91053ec752d9aa56df8061ba5e62c13431804a6b /src
parent	d3877c67d060d454ac66fde7b6ad41a2bb50d808 (diff)