Fixed a regression, that "export as" ran into a segmentation fault

Fixes #2386

src/control/jobs/BaseExportJob.cpp

@@ -41,7 +41,7 @@ auto BaseExportJob::checkOverwriteBackgroundPDF(fs::path const& file) const -> b
     return true;
 }
 
-auto BaseExportJob::getFilterName() -> string {
+auto BaseExportJob::getFilterName() const -> string {
     GtkFileFilter* filter = gtk_file_chooser_get_filter(GTK_FILE_CHOOSER(dialog));
     return gtk_file_filter_get_name(filter);
 }
@@ -68,10 +68,10 @@ auto BaseExportJob::showFilechooser() -> bool {
             gtk_widget_destroy(dialog);
             return false;
         }
-        this->filepath = Util::fromGFilename(gtk_file_chooser_get_filename(GTK_FILE_CHOOSER(dialog)));
-        Util::clearExtensions(this->filepath);
+        auto file =  Util::fromGFilename(gtk_file_chooser_get_filename(GTK_FILE_CHOOSER(dialog)));
+        Util::clearExtensions(file);
         // Since we add the extension after the OK button, we have to check manually on existing files
-        if (control->askToReplace(filepath)) {
+        if (testAndSetFilepath(std::move(file)) && control->askToReplace(this->filepath)) {
             break;
         }
     }
@@ -83,14 +83,17 @@ auto BaseExportJob::showFilechooser() -> bool {
     return true;
 }
 
-auto BaseExportJob::isUriValid(string& uri) -> bool {
-    if (!StringUtils::startsWith(uri, "file://")) {
-        string msg = FS(_F("Only local files are supported\nPath: {1}") % uri);
+auto BaseExportJob::testAndSetFilepath(fs::path file) -> bool {
+    try {
+        if(fs::is_directory(file.parent_path())){
+            this->filepath = std::move(file);
+            return true;
+        }
+    } catch (fs::filesystem_error const& e) {
+        string msg = FS(_F("Failed to resolve path with the following error:\n{1}") % e.what());
         XojMsgBox::showErrorToUser(control->getGtkWindow(), msg);
-        return false;
     }
-
-    return true;
+    return false;
 }
 
 void BaseExportJob::afterRun() {

src/control/jobs/BaseExportJob.h

@@ -33,14 +33,14 @@ public:
 
 public:
     virtual bool showFilechooser();
-    string getFilterName();
+    string getFilterName() const;
 
 protected:
     void initDialog();
     virtual void addFilterToDialog() = 0;
     void addFileFilterToDialog(const string& name, const string& pattern);
     bool checkOverwriteBackgroundPDF(fs::path const& file) const;
-    virtual bool isUriValid(string& uri);
+    virtual bool testAndSetFilepath(fs::path file);
 
 private:
 protected:

src/control/jobs/CustomExportJob.cpp

@@ -45,17 +45,18 @@ void CustomExportJob::addFilterToDialog() {
     }
 }
 
-auto CustomExportJob::isUriValid(string& uri) -> bool {
-    if (!BaseExportJob::isUriValid(uri)) {
+auto CustomExportJob::testAndSetFilepath(fs::path file) -> bool {
+    if (!BaseExportJob::testAndSetFilepath(std::move(file))) {
         return false;
     }
 
     // Extract the file filter selected
     this->chosenFilterName = BaseExportJob::getFilterName();
+    auto chosenFilter = filters.at(this->chosenFilterName);
 
     // Remove any pre-existing extension and adds the chosen one
-    Util::clearExtensions(filepath, filters[this->chosenFilterName]->extension);
-    filepath += filters[this->chosenFilterName]->extension;
+    Util::clearExtensions(filepath, chosenFilter->extension);
+    filepath += chosenFilter->extension;
 
     return checkOverwriteBackgroundPDF(filepath);
 }
@@ -105,12 +106,10 @@ auto CustomExportJob::showFilechooser() -> bool {
  * Create one Graphics file per page
  */
 void CustomExportJob::exportGraphics() {
-    bool hideBackground = filters[this->chosenFilterName]->withoutBackground;
-
+    bool hideBackground = filters.at(this->chosenFilterName)->withoutBackground;
     ImageExport imgExport(control->getDocument(), filepath, format, hideBackground, exportRange);
     imgExport.setPngDpi(pngDpi);
     imgExport.exportGraphics(control);
-
     errorMsg = imgExport.getLastErrorMsg();
 }
 

src/control/jobs/CustomExportJob.h

@@ -44,7 +44,7 @@ protected:
      */
     void exportGraphics();
 
-    virtual bool isUriValid(string& uri);
+    bool testAndSetFilepath(fs::path file) override;
 
 private:
     /**

src/control/jobs/PdfExportJob.cpp

@@ -12,8 +12,8 @@ PdfExportJob::~PdfExportJob() = default;
 
 void PdfExportJob::addFilterToDialog() { addFileFilterToDialog(_("PDF files"), "*.pdf"); }
 
-auto PdfExportJob::isUriValid(string& uri) -> bool {
-    if (!BaseExportJob::isUriValid(uri)) {
+auto PdfExportJob::testAndSetFilepath(fs::path file) -> bool {
+    if (!BaseExportJob::testAndSetFilepath(std::move(file))) {
         return false;
     }
 

src/control/jobs/PdfExportJob.h

@@ -25,7 +25,7 @@ public:
 
 protected:
     virtual void addFilterToDialog();
-    virtual bool isUriValid(string& uri);
+    bool testAndSetFilepath(fs::path file) override;
 
 private:
 };