Add books dialog: When a non-book file type is added the next time the dialog is used, preselect the "All files" filter. Fixes #1952562 [Update default selection filter for manual format adds via GUI](https://bugs.launchpad.net/calibre/+bug/1952562)

src/calibre/gui2/__init__.py

@@ -688,6 +688,26 @@ else:
     choose_files, choose_images, choose_dir, choose_save_file
 
 
+def choose_files_and_remember_all_files(
+    window, name, title, filters=[], select_only_single_file=False, default_dir='~'
+):
+    pref_name = f'{name}-last-used-filter-spec-all-files'
+    lufs = dynamic.get(pref_name, False)
+    af = _('All files'), ['*']
+    filters = list(filters)
+    filters.insert(0, af) if lufs else filters.append(af)
+    paths = choose_files(window, name, title, list(filters), False, select_only_single_file, default_dir)
+    if paths:
+        ext = paths[0].rpartition(os.extsep)[-1].lower()
+        used_all_files = True
+        for i, (name, exts) in enumerate(filters):
+            if ext in exts:
+                used_all_files = False
+                break
+        dynamic.set(pref_name, used_all_files)
+    return paths
+
+
 def is_dark_theme():
     pal = QApplication.instance().palette()
     col = pal.color(QPalette.ColorRole.Window)

src/calibre/gui2/actions/add.py

@@ -16,8 +16,8 @@ from calibre.constants import iswindows
 from calibre.ebooks import BOOK_EXTENSIONS
 from calibre.ebooks.metadata import MetaInformation, normalize_isbn
 from calibre.gui2 import (
-    choose_dir, choose_files, error_dialog, gprefs, info_dialog, question_dialog,
+    choose_dir, choose_files, choose_files_and_remember_all_files, error_dialog,
-    warning_dialog
+    gprefs, info_dialog, question_dialog, warning_dialog
 )
 from calibre.gui2.actions import InterfaceAction
 from calibre.gui2.dialogs.add_empty_book import AddEmptyBookDialog
@@ -139,7 +139,7 @@ class AddAction(InterfaceAction):
         ids = self._check_add_formats_ok()
         if not ids:
             return
-        books = choose_files(self.gui, 'add formats dialog dir',
+        books = choose_files_and_remember_all_files(self.gui, 'add formats dialog dir',
                 _('Select book files'), filters=get_filters())
         if books:
             self._add_formats(books, ids)
@@ -529,7 +529,7 @@ class AddAction(InterfaceAction):
             fmts = self.gui.device_manager.device.settings().format_map
             filters = [(_('Supported books'), fmts)]
 
-        books = choose_files(self.gui, 'add books dialog dir',
+        books = choose_files_and_remember_all_files(self.gui, 'add books dialog dir',
                 _('Select books'), filters=filters)
         if not books:
             return

src/calibre/gui2/linux_file_dialogs.py

@@ -163,7 +163,10 @@ def kdialog_choose_dir(window, name, title, default_dir='~', no_save_dir=False):
 def kdialog_filters(filters, all_files=True):
     ans = []
     for name, exts in filters:
-        ans.append('{} ({})'.format(name, ' '.join('*.' + x for x in exts)))
+        if not exts or (len(exts) == 1 and exts[0] == '*'):
+            ans.append(name + ' (*)')
+        else:
+            ans.append('{} ({})'.format(name, ' '.join('*.' + x for x in exts)))
     if all_files:
         ans.append(_('All files') + ' (*)')
     return '\n'.join(ans)
@@ -240,7 +243,10 @@ def zenity_choose_dir(window, name, title, default_dir='~', no_save_dir=False):
 def zenity_filters(filters, all_files=True):
     ans = []
     for name, exts in filters:
-        ans.append('--file-filter={} | {}'.format(name, ' '.join('*.' + x for x in exts)))
+        if not exts or (len(exts) == 1 and exts[0] == '*'):
+            ans.append('--file-filter={} | {}'.format(name, '*'))
+        else:
+            ans.append('--file-filter={} | {}'.format(name, ' '.join('*.' + x for x in exts)))
     if all_files:
         ans.append('--file-filter={} | {}'.format(_('All files'), '*'))
     return ans

src/calibre/gui2/qt_file_dialogs.py

@@ -56,8 +56,11 @@ class FileDialog(QObject):
         if filters:
             for filter in filters:
                 text, extensions = filter
-                extensions = ['*'+(i if i.startswith('.') else '.'+i) for i in
+                if not extensions or (len(extensions) == 1 and extensions[0] == '*'):
-                        extensions]
+                    extensions = ['*']
+                else:
+                    extensions = ['*'+(i if i.startswith('.') else '.'+i) for i in
+                            extensions]
                 etext = '%s (%s);;'%(text, ' '.join(extensions))
                 if len(etext) > 72:
                     has_long_filter = True