From 9dc8b42ec9bdd7e39bea3698d8c7b607fe604e4e Mon Sep 17 00:00:00 2001
From: Henning Gruendl <henning.gruendl@qt.io>
Date: Wed, 22 Feb 2023 14:55:53 +0100
Subject: [PATCH] QmlDesigner: Fix re-opening project error

Task-number: QDS-9242
Change-Id: Iecd0271014d2f3e3ea8b3cb13271c2cf4a612ce8
Reviewed-by: Thomas Hartmann <thomas.hartmann@qt.io>
---
 src/plugins/qmlprojectmanager/qmlproject.cpp | 14 ++++++++++++--
 1 file changed, 12 insertions(+), 2 deletions(-)

diff --git a/src/plugins/qmlprojectmanager/qmlproject.cpp b/src/plugins/qmlprojectmanager/qmlproject.cpp
index 2f7cc3699d0..86f22a2eba9 100644
--- a/src/plugins/qmlprojectmanager/qmlproject.cpp
+++ b/src/plugins/qmlprojectmanager/qmlproject.cpp
@@ -342,12 +342,22 @@ QString QmlBuildSystem::mainUiFile() const
 
 Utils::FilePath QmlBuildSystem::mainFilePath() const
 {
-    return projectDirectory().pathAppended(mainFile());
+    const auto mainFileString = mainFile();
+
+    if (mainFileString.isEmpty())
+        return {};
+
+    return projectDirectory().pathAppended(mainFileString);
 }
 
 Utils::FilePath QmlBuildSystem::mainUiFilePath() const
 {
-    return projectDirectory().pathAppended(mainUiFile());
+    const auto mainUiFileString = mainUiFile();
+
+    if (mainUiFileString.isEmpty())
+        return {};
+
+    return projectDirectory().pathAppended(mainUiFileString);
 }
 
 bool QmlBuildSystem::setMainFileInProjectFile(const Utils::FilePath &newMainFilePath)