diff --git a/src/plugins/autotest/testcodeparser.cpp b/src/plugins/autotest/testcodeparser.cpp
index 01b50a7e1e6..f4076153d5f 100644
--- a/src/plugins/autotest/testcodeparser.cpp
+++ b/src/plugins/autotest/testcodeparser.cpp
@@ -208,7 +208,7 @@ void TestCodeParser::onDocumentUpdated(const QString &fileName, bool isQmlFile)
     if (!project)
         return;
     // Quick tests: qml files aren't necessarily listed inside project files
-    if (!isQmlFile && !SessionManager::projectContainsFile(project, Utils::FileName::fromString(fileName)))
+    if (!isQmlFile && !project->isKnownFile(Utils::FileName::fromString(fileName)))
         return;
 
     scanForTests(QStringList(fileName));
diff --git a/src/plugins/projectexplorer/session.cpp b/src/plugins/projectexplorer/session.cpp
index 74c530d7b90..35608f91551 100644
--- a/src/plugins/projectexplorer/session.cpp
+++ b/src/plugins/projectexplorer/session.cpp
@@ -666,18 +666,13 @@ Project *SessionManager::projectForFile(const Utils::FileName &fileName)
 {
     const QList<Project *> &projectList = projects();
     foreach (Project *p, projectList) {
-        if (projectContainsFile(p, fileName))
+        if (p->isKnownFile(fileName))
             return p;
     }
 
     return nullptr;
 }
 
-bool SessionManager::projectContainsFile(Project *p, const Utils::FileName &fileName)
-{
-    return p && p->isKnownFile(fileName);
-}
-
 void SessionManager::configureEditor(IEditor *editor, const QString &fileName)
 {
     if (auto textEditor = qobject_cast<TextEditor::BaseTextEditor*>(editor)) {
@@ -691,7 +686,7 @@ void SessionManager::configureEditor(IEditor *editor, const QString &fileName)
 void SessionManager::configureEditors(Project *project)
 {
     foreach (IDocument *document, DocumentModel::openedDocuments()) {
-        if (projectContainsFile(project, document->filePath())) {
+        if (project->isKnownFile(document->filePath())) {
             foreach (IEditor *editor, DocumentModel::editorsForDocument(document)) {
                 if (auto textEditor = qobject_cast<TextEditor::BaseTextEditor*>(editor)) {
                         project->editorConfiguration()->configureEditor(textEditor);
diff --git a/src/plugins/projectexplorer/session.h b/src/plugins/projectexplorer/session.h
index c54bc6d9eee..9558b6bbfbf 100644
--- a/src/plugins/projectexplorer/session.h
+++ b/src/plugins/projectexplorer/session.h
@@ -115,7 +115,6 @@ public:
     static Project *projectForNode(Node *node);
     static Node *nodeForFile(const Utils::FileName &fileName);
     static Project *projectForFile(const Utils::FileName &fileName);
-    static bool projectContainsFile(Project *p, const Utils::FileName &fileName);
 
     static QStringList projectsForSessionName(const QString &session);