ProjectExplorer: Fix initial top level expansion of projects

For freshly created projects using the json wizard, this
expands the outermost level of that project's entry in
the project tree.

This intentionally does not trigger when reloading from existing
sessions do honor a user's choice after collapsing that
item manually.

Fixes: QTCREATORBUG-17800
Change-Id: I101efaea84e68a4e769c803918652a1447805b2b
Reviewed-by: Christian Kandeler <christian.kandeler@qt.io>

src/plugins/projectexplorer/jsonwizard/jsonwizard.cpp

@@ -354,6 +354,7 @@ void JsonWizard::openFiles(const JsonWizard::GeneratorFiles &files)
                 }
                 break;
             }
+            result.project()->setNeedsInitialExpansion(true);
             openedSomething = true;
         }
         if (file.attributes() & Core::GeneratedFile::OpenEditorAttribute) {

src/plugins/projectexplorer/project.cpp

@@ -160,6 +160,7 @@ public:
     Core::Id m_id;
     bool m_isParsing = false;
     bool m_hasParsingData = false;
+    bool m_needsInitialExpansion = false;
     std::unique_ptr<Core::IDocument> m_document;
     std::unique_ptr<ProjectNode> m_rootProjectNode;
     std::unique_ptr<ContainerNode> m_containerNode;
@@ -306,6 +307,16 @@ void Project::setActiveTarget(Target *target)
     }
 }
 
+bool Project::needsInitialExpansion() const
+{
+    return d->m_needsInitialExpansion;
+}
+
+void Project::setNeedsInitialExpansion(bool needsExpansion)
+{
+    d->m_needsInitialExpansion = needsExpansion;
+}
+
 Target *Project::target(Core::Id id) const
 {
     return Utils::findOrDefault(d->m_targets, Utils::equal(&Target::id, id));

src/plugins/projectexplorer/project.h

@@ -189,6 +189,9 @@ public:
         }, recv, this);
     }
 
+    bool needsInitialExpansion() const;
+    void setNeedsInitialExpansion(bool needsInitialExpansion);
+
 signals:
     void displayNameChanged();
     void fileListChanged();

src/plugins/projectexplorer/projectmodels.cpp

@@ -239,6 +239,10 @@ void FlatModel::addOrRebuildProjectModel(Project *project)
         if (m_trimEmptyDirectories)
             trimEmptyDirectories(container);
     }
+
+    if (project->needsInitialExpansion())
+        m_toExpand.insert(expandDataForNode(container->m_node));
+
     if (container->childCount() == 0) {
         auto projectFileNode = std::make_unique<FileNode>(project->projectFilePath(),
                                                           FileType::Project, false);