diff --git a/src/plugins/projectexplorer/projectmodels.cpp b/src/plugins/projectexplorer/projectmodels.cpp
index 4f4e69f180a..a8139f686ae 100644
--- a/src/plugins/projectexplorer/projectmodels.cpp
+++ b/src/plugins/projectexplorer/projectmodels.cpp
@@ -266,7 +266,8 @@ void FlatModel::addFolderNode(WrapperNode *parent, FolderNode *folderNode, QSet<
 {
     for (Node *node : folderNode->nodes()) {
         if (FolderNode *subFolderNode = node->asFolderNode()) {
-            if (!filter(subFolderNode) && !seen->contains(subFolderNode)) {
+            const bool isHidden = m_filterProjects && !subFolderNode->showInSimpleTree();
+            if (!isHidden && !seen->contains(subFolderNode)) {
                 seen->insert(subFolderNode);
                 auto node = new WrapperNode(subFolderNode);
                 parent->appendChild(node);
@@ -275,11 +276,9 @@ void FlatModel::addFolderNode(WrapperNode *parent, FolderNode *folderNode, QSet<
             } else {
                 addFolderNode(parent, subFolderNode, seen);
             }
-        }
-    }
-    for (Node *node : folderNode->nodes()) {
-        if (FileNode *fileNode = node->asFileNode()) {
-            if (!filter(fileNode) && !seen->contains(fileNode)) {
+        } else if (FileNode *fileNode = node->asFileNode()) {
+            const bool isHidden = m_filterProjects && fileNode->isGenerated();
+            if (!isHidden && !seen->contains(fileNode)) {
                 seen->insert(fileNode);
                 parent->appendChild(new WrapperNode(fileNode));
             }
@@ -353,19 +352,6 @@ Node *FlatModel::nodeForIndex(const QModelIndex &index) const
     return flatNode ? flatNode->m_node : nullptr;
 }
 
-bool FlatModel::filter(Node *node) const
-{
-    bool isHidden = false;
-    if (FolderNode *folderNode = node->asFolderNode()) {
-        if (m_filterProjects)
-            isHidden = !folderNode->showInSimpleTree();
-    } else if (FileNode *fileNode = node->asFileNode()) {
-        if (m_filterGeneratedFiles)
-            isHidden = fileNode->isGenerated();
-    }
-    return isHidden;
-}
-
 const QLoggingCategory &FlatModel::logger()
 {
     static QLoggingCategory logger("qtc.projectexplorer.flatmodel");
diff --git a/src/plugins/projectexplorer/projectmodels.h b/src/plugins/projectexplorer/projectmodels.h
index 8d177c8b0c7..b59e08e04fa 100644
--- a/src/plugins/projectexplorer/projectmodels.h
+++ b/src/plugins/projectexplorer/projectmodels.h
@@ -85,8 +85,6 @@ signals:
     void requestExpansion(const QModelIndex &index);
 
 private:
-    bool filter(Node *node) const; // Returns true if node is hidden.
-
     bool m_filterProjects = false;
     bool m_filterGeneratedFiles = true;