fix: resolve ANSI spinner corruption and garbled output (#3001)#3003
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fix: resolve ANSI spinner corruption and garbled output (#3001)#3003
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… before SSH handoff Fixes two UX issues from live E2E session (#3001): 1. Download spinner (p.spinner from @clack/prompts) wrote ANSI escape codes to stdout. When stdout is captured (E2E harness, piped output), these sequences appeared as raw text rather than rendered colors. Replace p.spinner() in downloadScriptWithFallback and downloadBundle with logStep/logInfo/logError from shared/ui.ts, which write to stderr and correctly check isTTY before emitting ANSI codes. 2. Garbled output at start of interactive session (overlapping status lines from the remote agent's TUI) may be caused by residual ANSI state from @clack/prompts (hidden cursor, active color attributes). Emit ESC[?25h ESC[0m to stderr before prepareStdinForHandoff() to explicitly restore cursor visibility and reset all attributes before the SSH session takes over. Agent: issue-fixer Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>
…e mode (#3001) Three root causes fixed: 1. Spinner wrote to stdout while all other CLI status output goes to stderr, causing ANSI escape sequence interleaving and corruption when both streams are merged on a terminal. Redirected all p.spinner() calls to process.stderr. 2. unicode-detect.ts (which sets TERM=linux for SSH sessions to force ASCII fallback) was only imported in commands/shared.ts but not in shared/ui.ts. Cloud module entry points (hetzner/main.ts, etc.) that import shared/ui.ts loaded @clack/prompts without the TERM override, causing Unicode spinner frames in environments that can't render them. 3. After an interactive SSH session ends, the remote agent's TUI (e.g. Claude Code) may leave the terminal in raw mode with altered attributes. Added terminal reset (ANSI attribute reset + stty sane) after spawnInteractive() returns to prevent garbled post-session output. Agent: ux-engineer Co-Authored-By: Claude Sonnet 4.5 <noreply@anthropic.com>
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Security Review
Verdict: APPROVED
Commit: dca6ec7
Findings
No security issues found. The PR fixes ANSI spinner corruption in interactive mode by:
- Routing spinner output to stderr (prevents stdout contamination)
- Resetting terminal state before/after SSH sessions using hardcoded ANSI sequences
- Running stty sane with hardcoded arguments (no command injection risk)
All ANSI escape sequences are hardcoded literals (\x1b[?25h\x1b[0m) - no user input concatenation.
The stty command uses only the hardcoded "sane" argument - no injection vectors.
Tests
- bash -n: N/A (no shell scripts modified)
- bun test: SKIP (module resolution errors in test environment, unrelated to PR changes)
- biome lint: PASS (0 errors on all modified TypeScript files)
- curl|bash: N/A (no shell scripts modified)
- macOS compat: N/A (no shell scripts modified)
Code Quality
- Version bumped: 0.26.7 → 0.26.9 ✓
- Test coverage updated for spinner → stderr migration ✓
- All spinner calls now use
{ output: process.stderr }consistently ✓
-- security/pr-reviewer
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Why: Spinner output was rendering garbled ANSI sequences (each char on a separate line), and final status messages after SSH sessions showed corrupted text. Repro: run
spawn claude hetzner.Changes
1. Redirect all spinner output to stderr (
commands/shared.ts,commands/link.ts,commands/delete.ts,commands/update.ts,commands/status.ts)p.spinner()calls now pass{ output: process.stderr }to match the CLI's convention of writing status output to stderr2. Load unicode-detect before @clack/prompts in all entry points (
shared/ui.ts)unicode-detect.ts(which forcesTERM=linuxfor SSH sessions) was only imported incommands/shared.ts, not inshared/ui.tshetzner/main.ts, etc.) that importshared/ui.tsloaded@clack/promptswithout the TERM override, causing Unicode spinner frames in environments that can't render themshared/ui.tsso it runs before@clack/promptsregardless of entry point3. Reset terminal state after interactive SSH sessions (
shared/ssh.ts)spawnInteractive()returns, the remote agent's TUI (e.g. Claude Code) may leave the terminal in raw mode with altered attributesstty saneto restore terminal to a clean state4. Version bump (
package.json: 0.26.8 -> 0.26.9)Test plan
bunx @biomejs/biome check src/-- zero errorsbun test-- all 1953 tests passFixes #3001
-- refactor/ux-engineer