The classic CLI status bar could appear twice after a horizontal terminal
resize — two bars at two widths with two different elapsed readings.
Root cause: prompt_toolkit's Application._on_resize() calls renderer.erase(),
which does cursor_up(_cursor_pos.y) + erase_down() using the _cursor_pos.y
cached from the LAST render at the OLD width (renderer.py:745). On a column
shrink the terminal reflows the already-painted full-width chrome into extra
physical rows, so the cached y undershoots: cursor_up doesn't climb past the
reflowed rows and erase_down leaves the old bar stranded ABOVE the live
origin. The next paint stacks a fresh bar below it. The existing post-resize
suppression hides the NEW bar for ~0.35s but never erases the already-reflowed
OLD one, so the ghost survives the whole window. Ctrl+L / /redraw clears it,
confirming a viewport wipe is the fix.
Fix: on a WIDTH change, _recover_after_resize now routes through the same
recovery as Ctrl+L — _clear_prompt_toolkit_screen(rebuild_scrollback=False)
(CSI 2J, visible viewport only) + _replay_output_history() — BEFORE delegating
to prompt_toolkit's resize. Banner-safe: 2J never touches scrollback history
(that's CSI 3J, which we don't send here), so the startup banner is preserved.
Rows-only resizes skip the clear (no reflow → no ghost) to avoid an extra
repaint. Tracks _last_resize_width to distinguish the two.
Tests: replace the now-obsolete 'never clears on resize' assertion with two
tests — rows-only resize delegates without clearing; width change clears the
viewport + replays and never wipes scrollback.
When the terminal shrinks, already-printed box-drawing rules (response,
reasoning, streaming TTS, background-task Panels) reflow into multiple
narrower rows — visible as duplicated horizontal separators / ghost
lines in scrollback. Similarly, prompt_toolkit redraws a fresh status
bar on SIGWINCH on top of one the terminal just reflowed, producing
double-bar artifacts on column shrink.
Two surgical changes:
1. Decorative scrollback boxes now use a new
`HermesCLI._scrollback_box_width()` helper that clamps to
`max(32, min(width, 56))`. The live TUI footer is unaffected and still
uses the full width. Covers: streaming response box (open + close),
reasoning box (open + close, both streaming and post-stream paths),
streaming-TTS box close, final-response Rich Panel, and the
background-task Rich Panel.
2. `_recover_after_resize()` now also sets a new
`_status_bar_suppressed_after_resize` flag so the dynamic status bar
and both input separator rules stay hidden until the next user input.
The flag is cleared in the process loop the moment the user submits
their next prompt, restoring chrome cleanly.
Tests:
- New `test_input_rules_hide_after_resize_until_next_input` covers the
flag's effect on rule heights.
- New `test_scrollback_box_width_caps_to_resize_safe_value` covers the
helper at floor / cap / mid-range / overflow.
- Existing resize-recovery test extended to assert the flag flips.
Refs: #18449#19280#22976
Salvage of #24403.
Co-authored-by: Szymonclawd <szymonclawd@mac.home>
Recover from SIGWINCH without clearing the physical screen or scrollback
buffer. The startup banner and tool summary are printed before
prompt_toolkit owns the live chrome, so they live in normal terminal
scrollback. Calling erase_screen() + \x1b[3J] on every resize removed
that UI permanently — _replay_output_history cannot reconstruct it
because the banner was never added to _OUTPUT_HISTORY.
Instead, just reset prompt_toolkit's renderer cache and invalidate so
the next incremental redraw starts from a clean slate, then let the
original on_resize handler recalculate layout for the new terminal
size. This matches the behaviour of bash/zsh/fish on SIGWINCH.
FixesNousResearch/hermes-agent#22999
The CLI renders through prompt_toolkit in non-full-screen mode, so every
repaint uses the renderer's tracked _cursor_pos.y to cursor_up() + erase
before drawing the new frame. Any time that tracked position drifts from
terminal reality, redraws stack on top of stale content instead of
overwriting it. Four user-visible bugs share this root cause.
Fixes:
- #5474 (SIGWINCH ghosts): the resize wrapper previously only handled
column-shrink reflow. Generalize it to force a full screen-clear
(erase_screen + cursor_goto(0,0)) and renderer.reset() on every resize
— covers widen, row-shrink, and multiplexer SIGWINCH-less redraws.
- #8688 (cmux/tmux tab switch): no SIGWINCH fires on focus regain, so
prompt_toolkit has no signal to recover. Add a _force_full_redraw()
helper, bound to Ctrl+L (standard bash/zsh/vim convention) and exposed
as /redraw. Users can manually clear drift without restarting Hermes.
- #14692 (DSR response leaks — ^[[53;1R): resize storms make
prompt_toolkit's CSI 6n queries race past the input parser; the
terminal's reply ends up as literal input text. Add a sibling of the
bracketed-paste sanitizer that strips \x1b[<row>;<col>R and the
caret-escape visible form from paste text, buffer text-filter, and
the input-processing loop.
The idle-redraw removal (#12641) is in the preceding commit from
@foxion37 — keeping them as separate commits preserves attribution.
