Fixed bug with number of recent files

The number of recent file actions in the menu is limited to
MAX_RECENT_FILES but on opening a new file which was not in the
list of recent files, it was added to the recent file list and
if there were more than MAX_RECENT_FILES in the list, an IndexError
was caused.

Added a few lines to mainwindow.open_file to ensure that the
list of recent files is never longer than MAX_RECENT_FILES.
Any new files are added to the start of the list and the end
of the list is clipped if necessary. This solved the above
problem.

src/hdf5view/main.py

@@ -53,7 +53,7 @@ def main():
     """
     parser = argparse.ArgumentParser()
     parser.add_argument('--version', action='version',
-                        version='%(prog)s {}'.format(__version__))
+                        version=f'%(prog)s {__version__}')
     parser.add_argument("-f", "--file", type=str, required=False)
     args = parser.parse_args()
 

src/hdf5view/mainwindow.py

@@ -258,6 +258,10 @@ def open_file(self, filename):
             # Add filename to top of recent files list
             self.recent_files.insert(0, filename)
 
+            # ensure not more than MAX_RECENT_FILES are kept:
+            if len(self.recent_files) > MAX_RECENT_FILES:
+                self.recent_files = self.recent_files[:MAX_RECENT_FILES]
+
             # Create a new widget and tab for the file
             # and select it.
             hdf_widget = HDF5Widget(hdf)