Ensure append mode works properly for stdout

rhpvorderman · rhpvorderman · commit 938f148f36a5 · 2024-03-20T09:46:09.000+01:00
diff --git a/src/xopen/__init__.py b/src/xopen/__init__.py
@@ -433,7 +433,7 @@ def flush(self) -> None:
 
 def _open_stdin_or_out(mode: str) -> BinaryIO:
     assert "b" in mode
-    std = sys.stdout if "w" in mode else sys.stdin
+    std = sys.stdin if mode == "rb" else sys.stdout
     return open(std.fileno(), mode=mode, closefd=False)  # type: ignore
 
 
