Add assert to make issue pypa#1949 more apparent

petamas · Jul 20, 2023 · 2fde5c4 · 2fde5c4
1 parent 0114a68
commit 2fde5c4
Showing 1 changed file with 3 additions and 1 deletion.
diff --git a/src/virtualenv/util/zipapp.py b/src/virtualenv/util/zipapp.py
@@ -24,7 +24,9 @@ def extract(full_path, dest):
 
 def _get_path_within_zip(full_path):
     full_path = os.path.abspath(str(full_path))
-    sub_file = full_path[len(ROOT) + 1 :]
+    prefix = ROOT + os.sep
+    assert full_path.startswith(prefix), f"full_path={full_path} should start with prefix={prefix}"
+    sub_file = full_path[len(prefix) :]
     if IS_WIN:
         # paths are always UNIX separators, even on Windows, though __file__ still follows platform default
         sub_file = sub_file.replace(os.sep, "/")