Activity

1. atagtm

   added

   type-bugAn unexpected behavior, bug, or errorAn unexpected behavior, bug, or error

   on Oct 12, 2025
2. StanFromIreland

   added

   stdlibStandard Library Python modules in the Lib/ directoryStandard Library Python modules in the Lib/ directory

   topic-venvRelated to the venv moduleRelated to the venv module

   on Oct 12, 2025
3. dr-carlos commented on Feb 5, 2026

   

   dr-carlos

   on Feb 5, 2026

   Last edited by dr-carlos

   Contributor

   More actions

   causes ls-like output on every command.

   Not entirely sure what this means, could you provide an example?
   I haven't been able to reproduce this on fish 4.1.2 or the latest fish (4.3.3)
4. gaborbernat commented on Jun 5, 2026

   

   gaborbernat

   on Jun 5, 2026

   Contributor

   More actions

   I found the root cause: a user-defined function . (or function source) that shadows fish's source builtin.

   The venv prompt override restores $status for the wrapped prompt with this line:

   echo "exit $old_status" | .

   . is the source builtin, but fish resolves a function ahead of a builtin for an undecorated command, so a function . shadows it even inside a pipe. Every prompt render then pipes exit $old_status into that function instead of sourcing. When the function lists the directory (dot-style navigation plugins do exactly this), the prompt prints a directory listing on every command. The status restore also breaks.

   Minimal reproduction (fish), confirmed on fish 4.1.2 (the reported version) and 4.7.1 against a venv from CPython main:

   python3 -m venv /tmp/venv-gh140006
   function . ; ls ; end          # stand-in for any plugin or config that shadows '.'
   source /tmp/venv-gh140006/bin/activate.fish
   # every prompt from here on runs your `.` function instead of `source`,
   # so the directory gets listed after each command

   The override only runs when VIRTUAL_ENV_DISABLE_PROMPT is unset, which is why a default setup hides it. tide (sets it here) and starship (sets it here) both disable the venv prompt, so their users never reach this code. The symptom needs the override active and . shadowed together.

   The fix forces the builtins so no user function intercepts the line:

   builtin echo "exit $old_status" | builtin source -

   fish runs a builtin-decorated command as a builtin directly, bypassing any shadowing function. I verified the fix on fish 4.1.2 and 4.7.1 with ., source, and echo all shadowed: the status restores and nothing leaks.

   The linked PR gh-144558 no longer exists (its URL returns 404 while neighboring numbers resolve), so no fix is open. I will open a PR that hardens the prompt override against shadowed builtins, with a regression test. Once it lands, @atagtm can confirm against the updated script.
5. FFY00

   added a commit that references this issue on Jun 22, 2026

   gh-140006: Harden fish prompt against shadowed builtins (#150936)

   ...

   0d540af
6. pyctrl

   added a commit that references this issue on Jul 5, 2026

   pythongh-140006: Harden fish prompt against shadowed builtins (python…

   ...

   69a5ca9