ca TUI: fix the railway harness launch hang, ⇧esc release, and the shift+enter newline - #1079
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Launching the railway harness left a pane holding nothing but the relay's banner. `railway-agent-tui` opens by writing its whole startup burst in one go — bracketed paste, focus reporting, the kitty keyboard query, DA1, then the cursor-position query — and then waits. crossterm uses DA1 as the sentinel in `supports_keyboard_enhancement`: it writes the kitty query and `ESC[c` immediately after, then reads until one of them answers, because a terminal too old to know the kitty query will still answer DA1. Answering the kitty query while ignoring DA1 is therefore the one combination that hangs outright — the harness is told the protocol exists and then waits on a reply that never comes, never reaching the cursor query the pane was already answering. Before the pane learned `ESC[?u` it answered neither, crossterm's two-second timeout expired, and the harness drew; adding half the handshake turned a slow launch into a stuck one. So answer DA1 too. Measured against the real binary under a pty: no DA1 reply and it emits 23 bytes and stops forever; with one it draws in full in 0.07s, which also retires the two-second timeout that was there before any of this.
codyde
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⌥esc stopped releasing the session pane because macOS cannot send it. Option is a compose key unless the terminal maps it to Meta, and the other ⌥ chords survive that by arriving as the character they compose to — ⌥f as `ƒ`, ⌥[ as a curly quote, which `alt_chord` already matches. Escape composes to nothing, so ⌥esc arrives as a bare Escape with no modifier left to tell it apart from the one meant for the agent. Shift is never composed and the kitty protocol reports a shifted Escape as `CSI 27;2u`, so ⇧esc is taken alongside it and is what the hints now name. ⌥esc, `^]` and `^o` all keep working. Modified Enter falls back to `ESC CR` rather than a bare `\r` when the remote side has not pushed the kitty protocol. A bare `\r` submits the half-written prompt, which is the one outcome shift+enter exists to prevent; `ESC CR` is the legacy newline chord harnesses have always taken, and the exact bytes Claude Code's own `/terminal-setup` binds shift+enter to. Worth recording why the CSI-u path alone was not enough: the kitty protocol exempts Enter, Tab and Backspace from disambiguate mode by design, so a stock terminal reports shift+enter as a bare `\r` with no modifier on it and there is nothing for `encode_key_for` to act on. Lifting that needs REPORT_ALL_KEYS_AS_ESCAPE_CODES, which crossterm cannot yet pair with the associated text those events carry — composed ⌥ characters, dead keys and IMEs would all break — so reporting shift+enter stays the terminal's to opt into.
codyde
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Three fixes in the
railway casession pane. All three are the pane failing to speak the terminal's side of a protocol.1. Fix: railway harness hung on launch — pane showed only the relay banner
railway-agent-tuiwrites its startup burst in one write — bracketed paste, focus reporting,ESC[?u,ESC[c,ESC[6n— then waits.ESC[c) as the sentinel insupports_keyboard_enhancement. The pane answeredESC[?ubut never DA1, so the harness waited on a reply that never came and never reached the cursor query the pane already answered.ESC[?62;22c.2. Fix: ⌥esc no longer released the session pane
ƒ, ⌥[ as a curly quote — whichalt_chordalready matches.CSI 27;3u); it is dead where Option composes, which is the default in Ghostty and Terminal.app.railway cato drive them #1013 shipped this chord as ⇧esc, TUI: replace the wizard-replay ⌥s with a proper settings card #1069 swapped it to ⌥esc.CSI 27;2u. ⌥esc,^]and^oare untouched, so terminals where ⌥esc already worked are unaffected. Hints read⌥/⇧esc / ^].3. Partial fix: shift+enter did not insert a newline in the harness
\rwith no modifier on it. There was nothing forencode_key_forto act on — the CSI-u encoding added earlier could never fire.ESC CRinstead of a bare\rwhen the remote has not pushed the kitty protocol. A bare\rsubmits the half-written prompt;ESC CRis the legacy newline chord, and the bytes Claude Code's/terminal-setupbinds shift+enter to./terminal-setup(or an equivalent keybind sendingESC CR), or Option-as-Meta plus ⌥enter, which already worked.REPORT_ALL_KEYS_AS_ESCAPE_CODESwould lift the exemption, but crossterm cannot pair it with the associated text those events carry — composed ⌥ characters, dead keys and IMEs would all break. Recorded in a comment onsetup_terminal.Tests
ESC[?62;22creplies or otherc-terminated sequences, and the real startup burst gets all three answers in the order asked.3 pre-existing
auth_simfailures on master, unrelated to this branch.