fix: fix fatal error when exporting virtools file

- fix fatal error that user only can export virtools file into existing file, rather than any new file.

bbp_ng/OP_EXPORT_virtools.py

@@ -44,9 +44,18 @@ class BBP_OT_export_virtools(bpy.types.Operator, UTIL_file_browser.ExportVirtool
             self.report({'ERROR'}, 'You must specify at least one encoding for file saving (e.g. cp1252, gbk)!')
             return {'CANCELLED'}
 
-        # check file name
+        # check file name, but has slightly difference with importer.
+        # when exporting, file can be inexisting in file system, so we can't check it directly.
         filename = self.general_get_filename()
-        if not os.path.isfile(filename):
+        bad_filename: bool = False
+        # for filename, at first, it should not be empty surely.
+        if len(filename) == 0:
+            bad_filename = True
+        # then, if it is existing, it should be a file, otherwise everything is okey.
+        if os.path.exists(filename) and (not os.path.isfile(filename)):
+            bad_filename = True
+        # now, show message and exit if we have bad file name
+        if bad_filename:
             self.report({'ERROR'}, 'No file was selected!')
             return {'CANCELLED'}
 

bbp_ng/blender_manifest.toml

@@ -6,7 +6,7 @@ schema_version = "1.0.0"
 # Example of manifest file for a Blender extension
 # Change the values according to your extension
 id = "bbp_ng"
-version = "4.3.0"
+version = "4.3.1"
 name = "Ballance Blender Plugin"
 tagline = "The specialized add-on served for creating game map of Ballance"
 maintainer = "yyc12345 <yyc12321@outlook.com>"