`Pane.send_keys` types nothing and raises nothing for text that starts with `-`

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Assessment

Difficulty
2/5
Estimated time
1-3 hours
Newbie friendliness
82/100
Issue type
Bug
Clarity
Clearly specified
Activity status
Active
Tech stack
python
Domain
backend-api-design, cli

Research direction

Read src/libtmux/pane.py around the Pane.send_keys argv construction at line 847 and check how Pane.cmd handles tmux arguments. Reproduce with the provided -n hello input, then verify that it reaches the pane or that tmux's error is raised. Done when both literal=False and literal=True behave as expected for text beginning with a dash.

Written by the indexing model from the issue text.

Description

bug
Summary

Pane.send_keys("-n hello") returns normally, yet nothing reaches the pane, with literal=False and with literal=True. tmux rejects the call with unknown flag -n and exit status 1. send_keys passes the text right after its own flags with no --, and does not check the result. Text that starts with - is ordinary in scripted input: command-line flags, Markdown bullets, negative numbers.

Reproduction
  1. Start a private server with a sh pane and send text that starts with -:
import libtmux
srv = libtmux.Server(socket_name="sendkeys-dash", config_file="/dev/null")
pane = srv.new_session("probe", window_command="sh").active_window.active_pane
pane.send_keys("-n hello", enter=False)
pane.send_keys("-n hello", enter=False, literal=True)
print(repr(pane.capture_pane()[-1]))
srv.kill()
  1. Send the same text through Pane.cmd with --:
proc = pane.cmd("send-keys", "-l", "--", "-n hello")
Expected

The pane shows $ -n hello, or send_keys raises with tmux's error.

Actual

The pane shows '$'. Both calls return without raising. The raw call without -- fails with command send-keys: unknown flag -n; with -- it types the text.

Environment
  • libtmux: master at 886b1cd (v0.62.0 plus 114 commits)
  • tmux: 3.8 (system build reports 3.8a)
  • Python: run with uv run --frozen from the libtmux checkout
  • OS: Linux (WSL2), private -L socket, -f /dev/null
Evidence 
send_keys('-n hello', literal=False): no exception
send_keys('-n hello', literal=True): no exception
pane line after sends: '$'
pane.cmd('send-keys', ('-l', '-n hello')): returncode=1 stderr=['command send-keys: unknown flag -n']
pane.cmd('send-keys', ('-l', '--', '-n hello')): returncode=0 stderr=[]
pane line after raw sends: '$ -n hello'
References
Dominant language
Python
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