completion arguments may start with a "/"

1 files changed, 6 insertions, 1 deletions

diff --git a/src/click/shell_completion.py b/src/click/shell_completion.py
index b444bae..cad080d 100644
--- a/src/click/shell_completion.py
+++ b/src/click/shell_completion.py
@@ -450,7 +450,12 @@ def _is_incomplete_argument(ctx: Context, param: Parameter) -> bool:
 
 def _start_of_option(value: str) -> bool:
     """Check if the value looks like the start of an option."""
-    return not value[0].isalnum() if value else False
+    if not value:
+        return False
+
+    c = value[0]
+    # Allow "/" since that starts a path.
+    return not c.isalnum() and c != "/"
 
 
 def _is_incomplete_option(args: t.List[str], param: Parameter) -> bool: