[robobun]

Fixes #27560

Problem

• bun repl takes every byte of stdin for a key press, also in piped or pasted text. printf 'var proc\t= 5\n' | bun repl runs var process= 5.
• The cause is one reader for every stdin: the loop in run_with_vm (src/runtime/cli/repl.rs:2346) calls read_key for each byte.

Fix

• Commit 1: without a raw terminal, the new read_text_lines takes stdin as lines of text.
• Commit 2: on a raw terminal the REPL sets bracketed paste. A paste arrives as Key::Paste, waits for Enter and runs as one entry.
• Correct: a byte is a key only where a key press can produce it, as in node -i with piped output.
• Verified: test/js/bun/repl/repl.test.ts, 79 new tests, 70 fail on 1.4.3. Self-reviewed twice: 81 concerns raised, 78 addressed, 3 rejected (Notes).

Background

• In raw mode a terminal sends key presses as bytes (Tab is byte 9). In line mode it sends whole lines.
• Bracketed paste is a terminal mode (ESC[?2004h): the terminal sends ESC[200~, the pasted bytes, ESC[201~. The mode outlives the process, so bun_restore_stdio resets it.
• Considered a guard in the Tab arm: it fixes 1 of 31 control bytes and no paste.

Downsides

• A multi-line paste now waits for Enter and runs as one entry. A paste with no markers (tmux send-keys) stays keys.
• A pipe no longer drives the editor: a TAB does not complete, 0x04 does not quit. A last line with no line end runs.
• Cost: +16 bytes per entered line, +16 instructions per key (0.11%, A/A spread 59), +5,888 bytes of binary.

Notes

Origin. A fuzz run on the REPL's stdin found the key decoding of piped and pasted text. There is no GitHub issue for it. The key loop is unchanged since the first native REPL (#26304). #27560 is a separate report: a recalled multi-line entry is drawn again on each key. The paste needs the same drawing code, so this PR fixes it too.

Two commits. A maintainer can take the first one alone.

1. The text reader. It changes repl.rs, the test file and the docs only. It also has the parts that do not depend on a paste: read_csi, the display form of control bytes, and the rows of a multi-line entry (bun repl: code repeatly printed when deleting multi-line history code #27560).
2. Bracketed paste. It adds Key::Paste, the mode switches, the keys that act on a paste that waits, and the DEC_MODES row in src/bun_core/tty.rs with its two call sites.

The later commits are a merge of main and the fixes from review. 8d7e6ea belongs to the first commit. 32a1ee4 belongs to the second.

For a maintainer to decide

• The DEC_MODES row puts one more call on the exit path of every bun process. Reset cursor and mouse modes on every exit that restores termios #41977 adds the same table for bun update -i and has no review yet. May the row land before it?
• A paste waits for Enter and runs as one entry. 1.4.3 runs each pasted line as it arrives.
• .editor on a pipe keeps the 1.4.3 rule: a line that starts with 0x04 runs the lines, one that starts with 0x03 cancels them, and the end of a pipe runs nothing. The other choice is to refuse .editor there, as node -i does.

Repro. Piped input, stdout a pipe. main is a release build of 91e7e3b.

Input	1.4.3 and main	this PR	node -i 26.3
"a<TAB>b"	"a b"	"a\tb"	'a\tb'
var proc<TAB>= 5; typeof proc + "," + typeof process	"undefined,number"	"number,object"	'number,object'
a block indented with TAB	213 completions, then the output	the output	the output
"ab<DEL>c".length	2	4	4
1+1, ESC [ A, 2+2	2, 2, 4	2, SyntaxError, 4	2, SyntaxError, 4
"a<NUL>b".length	2	3	3
1+1, 2+2 with CR LF	2, empty prompt, 4, empty prompt	2, 4	2, 4
1+1, 2+2 with no final line end	2	2, 4	2, 4

On a pty, each of the first six rows gives the PR column when the text is pasted between ESC[200~ and ESC[201~. A paste of the two lines 1+1 and 2+2 prints 4 only, because it is one entry. With stdin a pipe and stdout a terminal, node decodes keys ("ab<DEL>c".length is 2). This PR reads text there too (4): stdin is not a terminal, so no key press can be in it.

The rule for each kind of stdin

• A terminal that the REPL put in raw mode: key presses (read_keys). drawing is Some only there.
• Everything else: lines of text (read_text_lines). That is a pipe, a file, a terminal with stdout redirected, and a terminal that refuses raw mode. A line ends at LF, CR LF or CR. A CR LF that two reads cut is one line end.
• At the end of a pipe or a file, a last line with no line end runs. A read error runs nothing and the exit code stays 0, as on main.
• On a terminal in line mode, a read of no bytes is the Ctrl+D key: the last line runs and .editor finishes. On a terminal in another mode it is also a read timeout or a hang-up, and on a Windows console also Ctrl+C. Nothing runs there.
• 0x04 outside .editor is text, as in node -i. .exit and the end of input end a session.

Bracketed paste

• The mode is on only while the prompt is shown. refresh_line sets it with the first write of a redraw, and leave_input resets it with a write that it makes anyway. So prompt() and a child process that an entered line starts never read the markers. JS that runs while the prompt is shown can: a getter that completion or the ghost text calls.
• handle_paste changes CR LF and CR to LF and inserts the text. Bytes that are not UTF-8 become U+FFFD. The line end that ends a paste stays, so a second paste starts on the next line. Enter does not count it as part of a REPL command.
• A paste waits for Enter, also when it has several lines. VS Code, Windows Terminal and Ghostty show no paste warning once a program has set the mode, because they expect the program not to run the lines.
• The lines run as one entry, as in .editor. So only the last value prints, an exception ends the entry, and a SyntaxError or a repeated const runs nothing. The other choice is what bash does: hold the paste, then enter each line at Enter. That cuts a statement that continues on the next line (.then on its own line, else after }), which is what 1.4.3 does to such a paste.
• A REPL command can take a pasted argument of several lines (.copy). A file name cannot. A paste whose first line is only a command name is code.
• A start marker with no end marker: Ctrl+C with no more input within 500 ms ends the paste. Before the end marker, every other byte is text.
• The Esc key and then a paste: the ESC of the start marker is not lost. After two ESC, [ or O starts a sequence (ESC ESC [ A is Up). Any other byte is the next key, as on main.
• Down with no newer entry keeps the line, and Ctrl+C in .editor or at ... clears it. Without these, one key erased a paste that waits, or left it to run at the next Enter. repl: keep the line on Down with no newer entry, reset the history cursor at every line start #46084 and repl: clear the typed line on Ctrl+C in every mode, evaluate it on Ctrl+D in editor mode #46083 make the same two changes.

Also changed in the REPL. Each item has a test.

• read_csi reads a CSI sequence to its final byte. A sequence that names no key leaves no text on the line. Before, F5 (ESC[15~) left ~ and a paste marker left 0~. At most 64 parameter bytes are read. A byte that cannot be in a key sequence ends it and is the next key.
• An entry of several lines is drawn one row per line, and each later row starts with ... (bun repl: code repeatly printed when deleting multi-line history code #27560). Before, each key added a copy of the upper rows.
• An entry with more lines than the terminal has rows is drawn as the lines around the cursor that fit. A redraw cannot go back to a row that scrolled off the top. Still wrong, as on main: one line that is longer than the whole screen.
• A TAB in the line is drawn as blanks to the next tab stop. Other control characters are drawn as escapes (\x1b). The line keeps the bytes. A text session writes such bytes to the history file, so Up needs this.
• .load, .save, .history and Unknown command escape control characters in the names they print. .load and .save refuse a file name with a NUL byte or a line break.
• .editor keeps a line of only blanks or tabs as it is, and Ctrl+D takes a line that was typed and not entered.
• A control byte at the top level of an entry, outside a string, does not start a multi-line entry. A piped ESC [ A line gives SyntaxError: Invalid character '\^[' and the next lines run. Inside an open bracket the entry goes on: there the byte can be in a comment or a regex literal.
• A line with await no longer puts a line-mode terminal in raw mode.

Piped inputs that change and are not in the table

• A TAB before a REPL command (<TAB>.load file) is text now, so the line is not a command. 1.4.3 and node load the file.
• An arrow key inside an open bracket (foo(, Enter, Up) is text that waits for the closing bracket. .break cancels the entry.
• A driver that sends 0x04 to quit gets SyntaxError: Invalid character '\^D'. The session ends at the end of input.
• Input in UTF-16 worked by accident on 1.4.3, because NUL was a key that did nothing. It is now SyntaxError: Invalid character: '\0'.
• The REPL reads up to 256 bytes ahead of the line that it runs, as on main. Code that reads stdin itself (prompt()) loses lines. New: the cut-off head of a line can now run as the last line.

Measurements. Release builds of 91e7e3b and of the first two commits on it, Linux x64. The fixes from review are not in these numbers. They add the row count of visible_lines to the path for an entry with control bytes, and one store per redraw for the height of the terminal. strace, perf, valgrind and bloaty are not in the container. The tools are /proc/<pid>/io, gdb catchpoints, perf_event_open and objdump.

• typed key on a pty: 1 read + 8 write(2) + 1 ioctl (main: 1 + 8 + 1, /proc/<pid>/io slope, 200 vs 1000 keys)
• bracketed-paste arming: +0 bytes/+0 write(2) per key, +16/+0 per entered line, +8/+0 at the first prompt and +8/+0 at .exit
• typed-key path: +15.6 instructions per key (14,142.0 to 14,157.6, 10 interleaved runs, A/A spread 58.5). Repl::refresh_line has 336 and 439 instructions, leave_input 134 and 149.
• process exit: bun_restore_stdio makes 1 more call. 14 instructions run when no mode is set, with no syscall. bun -e 0 makes 0 write(2) on both builds.
• piped LF line: 3.000 write(2), 0.019 read(2), 49.1 to 49.4 allocations on both builds. stdout is identical for 22 of 22 inputs of the existing piped tests. ioctl per awaited piped line: 1 to 0.
• 52-byte bracketed paste: 1 redraw, 8 write(2). The same bytes with no markers: 52 redraws, 416 write(2) on both builds.
• control bytes kept as text (31 values, Linux pty): pipe 31/31, file 31/31, bracketed paste 31/31 (main 0/31 each)
• release binary: text 107,073,052 to 107,078,940 bytes. Data and bss do not change.

Exit paths. ESC[?2004l is the last mode switch on 8 close paths, each a test: .exit, Ctrl+D, Ctrl+C twice, process.exit() in a line, process.exit() in a getter that Tab completion runs, SIGTERM and SIGINT at the first prompt, SIGTERM after an awaited line. On the normal exits it comes before the exit listeners run. A ninth test crashes the process through the crash handler. A REPL that is stopped in the background of a stty tostop terminal still ends on SIGTERM, with the reset written (40 of 40 runs).

Not covered, and termios stays raw on these routes on main too:

• SIGINT from another process after an awaited line. The REPL leaves SIGINT at its default action after a wait, as on main. bun test --parallel, repl: act on a signal at once, and survive its repeat #45756 changes that rule.
• SIGTERM or SIGINT after the session removed its last listener for that signal. process.off then installs the default action.
• SIGHUP, SIGQUIT, SIGKILL and a hang-up.
• A Rust panic!. Its hook does not restore the terminal. The crash handler for a segfault does.

Not in this PR

• bun init and bun update -i have their own three-byte escape decoders. Shift+Up (ESC[1;2A) picks React in bun init and selects every package in bun update -i. That is a separate fix.
• The table has 1 of the 5 DEC private modes that bun sets. The cursor and mouse modes of bun init and bun update -i (Cursor does not reset when pressing Ctrl+C during interactive update #30890) are Reset cursor and mouse modes on every exit that restores termios #41977.
• bun --interactive (node:repl) does not change.
• The printer escapes a control byte in a regex literal (Transpiler rewrites raw NUL bytes (0x00) in regex literals: match failure before 1.3.12, RegExp.prototype.source still corrupted in 1.3.14 #33930, raw tagged template literals show escapes for non ascii text #8745).
• is_incomplete_code decides with a bracket counter which lines make one entry (REPL doesn't know how to handle regex literals #37326, repl: recognize regex literals and comments in continuation detection #37327). A piped // don't line still opens a string.
• In a text session the REPL still writes color escapes, .clear and the OSC 52 of .copy to the pipe. That is on main too.

Relation to open PRs

• repl: evaluate a last line that has no newline at the end of piped input #46126 runs a last piped line with no newline. This PR has that rule and its 11 tests. If this PR merges, repl: evaluate a last line that has no newline at the end of piped input #46126 is covered. One difference: on a terminal in line mode, a half line and then Ctrl+D twice runs the line here, as in node -i | cat.
• repl: redraw a recalled multi-line history entry in place #46095 draws a recalled multi-line entry (bun repl: code repeatly printed when deleting multi-line history code #27560). This PR has the same write_lines and Layout::advance_lines and its 10 tests. If repl: redraw a recalled multi-line history entry in place #46095 merges first, this PR rebases and that code leaves its diff. The two assertions that repl: redraw a recalled multi-line history entry in place #46095 adds to LineEditor::insert do not hold for a paste.
• repl: clear the typed line on Ctrl+C in every mode, evaluate it on Ctrl+D in editor mode #46083 and repl: keep the line on Down with no newer entry, reset the history cursor at every line start #46084: this PR has their changes to handle_ctrl_c, to Ctrl+D in .editor and to Down. It does not have the reset of the history position at each line start (repl: keep the line on Down with no newer entry, reset the history cursor at every line start #46084). 24 of their tests send key bytes through a pipe. After this PR a pipe holds text, so those tests need a pty.
• Reset cursor and mouse modes on every exit that restores termios #41977: see the first question above. The second of the two to merge adds its rows.
• bun test --parallel, repl: act on a signal at once, and survive its repeat #45756 and CLI: fixes for bun run, flags, bunfig.toml, .env, --filter, bun init and completions #46007 edit enable_signals_during_wait and sigint_handler. This PR changes one condition in disable_signals_during_wait.
• Bun.highlight: syntax highlighting to HTML and ANSI, on the formatter's parsers #45208 removes the fmt import of repl.rs. The new calls here use the full path bun_core::fmt::, so both merge orders compile. Hardening: fix crashes across the runtime, bundler, dev server, shell and CLI #46021 is merged, and the branch has a merge of main for it.
• repl: bind page up and page down to first and last history entry #38748 binds PageUp and PageDown. read_csi returns both keys.
• repl: keep multi-line history entries on one line of the history file #38023 keeps a multi-line entry on one line of the history file. Without it, an entry of several lines comes back as one entry per line after a restart, as on main. A paste is now a second source of such entries.
• repl: pump event loop while waiting for stdin so timers and IPC fire #30560 polls stdin in the key loop. After this PR its wait belongs in fill_stdin_buf, the one read that both readers use.
• The branch robobun/c1f23755/repl-input has no PR. It holds another text reader, with node's rule for a paste (a TAB with more bytes in the same read is text). This PR replaces that commit.

Considered

• node's rule for a paste on a terminal. It covers TAB only: DEL, Ctrl+U and Ctrl+A in the same read stay keys. A TAB that ends a read is a key: offset 4094 in node, offset 255 with the 256-byte reads here.
• Escape control bytes when a paste is inserted. Rejected: it changes the pasted program. The display form is made at draw time only.
• The design review picked a caret form (^[) for the display of control bytes. The code uses the shared bun_core::fmt::escape_control_chars helpers (\x1b), so that a name reads the same in every message.
• Restore the SIGINT action from before an awaited line. A first version did. It left a stale handler when the line removed its own listener, so it is not here.

Self-review. Two reviews, 36 and 45 concerns. 78 addressed. The 3 rejected ones, all from the first review, each ask for the opposite of another concern:

• Keep the entry of each pasted line. Rejected: the paste waits for Enter.
• Keep a REPL-only flag for the exit reset. Rejected: the reset is one row in the bun_core::tty table, with the names of Reset cursor and mouse modes on every exit that restores termios #41977.
• Leave is_incomplete_code as it is. Rejected: one arrow key made a piped session silent.

Two concerns of the second review got the other option that it named: .editor on a pipe is not refused, and the reader is not stacked on #46126.

Tests. 208 tests: 129 from main, unchanged, and 79 new. 21 of the new ones come from #46095 and #46126.

• Release build of the first two commits: the file passes 23 of 23 runs. The 3 signal tests pass 50 of 50 runs. A bun test --parallel=3 batch of 8 files passes 10 of 10 runs, and 5 of 6 with 24 busy processes on 12 cores. The one failure there is a test from main that hit its 3 s screen deadline.
• Debug build (ASAN) of the first two commits: the file passes 7 of 9 runs on an idle machine. The other 2 runs had only timeouts: the node:repl test is hollow until start() from main in both, and 4 paste tests in one. Right after a build, while the disk is busy, more tests of both kinds go over their 5 s. With the fixes from review: 4 of 4 runs.
• 1.4.3: 136 pass, 72 fail. 70 of the 72 are new. The other 2 are tests of main for a fix that is newer than 1.4.3. The 9 new tests that pass there pin what must stay.
• In a debug build a second thread can take the SIGTERM of the stopped-job test. The main thread then reads the terminal from the background and the kernel stops the job with SIGTTIN. This happens without this change too (7 of 40 runs on a debug build of main, 0 of 240 on release builds). The test continues such a job.

Platforms. Locally the tests ran on Linux x64 only. CI runs the file on macOS and Windows.

• bun run rust:check-all passes 12 of 12 targets.
• 23 of the new tests use a pipe and run on Windows too. The pty tests are in the existing describe.todoIf(isWindows) block. The call in windows_stdio::restore has no test.
• Windows keeps Ctrl+C a console signal in raw mode, so a 0x03 in a paste ends the REPL there. Windows Terminal removes control characters other than TAB, CR and LF from a paste.
• The stopped-job test needs job control in a shell script. It runs on glibc Linux, where sh is dash or bash 5. The sh of macOS (bash 3.2) does not run it.
• The tests compare the local flags of the terminal without PENDIN. macOS sets that state bit when a terminal goes back to line mode.

---

no test proof · iteration 0 · platform-specific test(s) that do not run on this machine, deferring to CI, which covers all platforms: test/js/bun/repl/repl.test.ts

[robobun]

Status: ready for review

How the bug was reproduced (Bun 1.4.3 and main at 91e7e3b, Linux x64):

printf 'var proc\t= 5; typeof proc + "," + typeof process\n' | bun repl

This prints "undefined,number": the TAB byte runs completion, so the line becomes var process= 5. With this PR it prints "number,object", as node -i does. On a pty, the same line between the paste markers ESC[200~ and ESC[201~ gives the same two results.

Test file: test/js/bun/repl/repl.test.ts (79 new tests, 70 of them fail on 1.4.3).

[robobun]

^{Updated 4:05 AM PT - Oct 22nd, 2026}

❌ @robobun, your commit 32a1ee4 has some failures in Build #130756 (All Failures)

---

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bunx bun-pr 46248

That installs a local version of the PR into your bun-46248 executable, so you can run:

bun-46248 --bun

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Walkthrough

The REPL adds piped stdin and bracketed-paste support, updates multiline editing and rendering, and resets tracked terminal modes during restoration. Documentation and tests cover these input and terminal behaviors.

Changes

REPL input and terminal handling

Layer / File(s)	Summary
Input parsing and paste submission src/runtime/cli/repl.rs, docs/runtime/repl.mdx, test/js/bun/repl/repl.test.ts	The REPL parses terminal sequences and piped text, buffers bracketed pastes, and submits normalized input. Documentation and tests cover piped input, paste behavior, and input edge cases.
Multiline editing and rendering src/runtime/cli/repl.rs, test/js/bun/repl/repl.test.ts	The line editor tracks control bytes and multiline layout. Rendering uses continuation prompts, and .load and .save reject file names containing NUL or line breaks. Tests cover multiline history, rendering, and file-name validation.
Terminal mode restoration src/bun_core/tty.rs, src/bun_core/output.rs, src/jsc/bindings/c-bindings.cpp, src/runtime/cli/repl.rs, test/js/bun/repl/repl.test.ts	The REPL tracks bracketed-paste mode and resets active DEC modes during terminal restoration. Tests cover mode cleanup, terminal restoration, and process termination.

Suggested reviewers: jarred-sumner

Priority: ➖ Normal

Severity of issue fixed: Low

Merge Risk: ⚪ Minimal · up to 32a1e

The REPL input and terminal changes show no concrete merge-blocking issue. The earlier test-timeout concern has been addressed. The macOS and Windows behaviors were not run, but nothing in the evidence shows a failure there.

Pre-merge checks: 3 · 1

Failed checks: 1 warning

Check name	Status	Explanation	Resolution
Out of Scope Changes check		The only supplied active direct issue is #27560, which covers recalled multi-line history rendering. The PR also changes non-terminal stdin parsing, bracketed-paste handling, DEC-mode tracking and exi…	Keep this PR limited to the #27560 multi-line history rendering changes and their tests, or link active issues that explicitly require the stdin, paste, terminal-mode, command, signal, and documentation changes.

Passed checks: 3 passed

Check name	Status	Explanation
Description check		The description clearly explains the problem, implementation, behavior changes, limitations, and verification results. It does not use the exact template headings, but it includes the required informa…
Title check		The title clearly and concisely summarizes the primary changes: non-terminal stdin is read as text lines, and bracketed pastes are handled as text.
Linked Issues check		Issue #27560 requires stable rendering while a recalled multi-line history entry is edited. The PR adds multi-line layout advancement, continuation prompts, viewport-aware drawing, and related redraw …

Full details: Description check

Explanation

The description clearly explains the problem, implementation, behavior changes, limitations, and verification results. It does not use the exact template headings, but it includes the required information, including how the changes were verified.

Full details: Linked Issues check

Explanation

Issue #27560 requires stable rendering while a recalled multi-line history entry is edited. The PR adds multi-line layout advancement, continuation prompts, viewport-aware drawing, and related redraw logic in src/runtime/cli/repl.rs. The REPL tests include multi-line history editing and rendering coverage. These changes address the issue requirement.

Full details: Out of Scope Changes check

Explanation

The only supplied active direct issue is #27560, which covers recalled multi-line history rendering. The PR also changes non-terminal stdin parsing, bracketed-paste handling, DEC-mode tracking and exit resets in src/bun_core/tty.rs, CSI decoding, .editor behavior, file-name validation, signal handling, and related documentation and tests. These changes implement behavior outside #27560. The issue does not connect them to its rendering requirement.

Resolution

Keep this PR limited to the #27560 multi-line history rendering changes and their tests, or link active issues that explicitly require the stdin, paste, terminal-mode, command, signal, and documentation changes.

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Inline comments:
Review comments at @test/js/bun/repl/repl.test.ts:
- Line 2445: Remove the explicit 20_000 timeout argument from the affected test
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retaining the inner waitFor deadline. Also remove the nearby comment explaining
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[claude]

Beyond the inline findings, I also checked the stdin_buf_start -= 1 push-backs in read_csi and read_key (each follows a successful read_byte, which leaves stdin_buf_start >= 1 with the byte still in the 256-byte buffer, so no underflow or stale byte), and the exit-path reset in src/bun_core/tty.rs (reset_active_dec_modes uses only atomics, the stdio tty flag and raw write(2) with SIGTTOU blocked, so the async-signal-safe claim holds). The .editor Ctrl+D with stdout redirected case was also examined and not reproduced from the code.

Extended reasoning...

The change reworks REPL stdin handling in src/runtime/cli/repl.rs (text-line reader for non-raw stdin, bracketed paste, a new CSI parser, multi-row drawing) and adds a process-exit DEC-mode reset in bun_core/tty.rs wired through bun_restore_stdio and the Windows stdio restore. It touches no auth, crypto or injection surface, but it is a large, behavior-changing terminal-input change with several confirmed inline findings, so a human look is warranted; the note above records only what was additionally ruled out.

Findings marked 🟡 are optional suggestions and need no follow-up push.

Additional findings (outside the current diff — GitHub can't attach inline comments there):

• 🟡 src/runtime/cli/repl.rs — After one awaited line, a SIGINT at the prompt leaves the user's shell in bracketed-paste mode, so a later paste in the shell types ESC[200~ as text; the base never set that mode. disable_signals_during_wait at src/runtime/cli/repl.rs:1224 installs SIG_DFL instead of the onExitSignal handler that bun_initialize_process set, so bun_restore_stdio and Bun__ttyResetActiveDecModes (src/jsc/bindings/c-bindings.cpp:598) never run on that exit. Fix: save the previous disposition with sigaction's oldact in enable_signals_during_wait and restore it, so every signal exit still writes the ?2004l reset the PR relies on.

  Why this was flagged

  The PR turns on DEC mode 2004 at every prompt (refresh_line, src/runtime/cli/repl.rs:1519) and relies on the signal path for an abnormal exit: tty.rs:121 says every exit through bun_restore_stdio resets it, and c-bindings.cpp:770-773 installs onExitSignal for SIGINT only at startup. The first line with await calls enable_signals_during_wait (:1163), and disable_signals_during_wait then writes SIG_DFL at :1224 instead of the saved handler. From then on, a SIGINT from kill -INT, a timeout wrapper or a supervisor at the prompt kills the process with no handler; raw termios is left (that half is on the base too) and now the terminal also stays in bracketed paste, which the base never enabled. Shells without readline bracketed-paste support (dash, older bash, fish configs that disable it) then receive paste markers as typed text. Remedy: restore the previous sigaction instead of SIG_DFL.

  Verification: Triggered when, after any line that awaited a promise, the REPL receives an externally sent SIGINT while the prompt is shown. disable_signals_during_wait (src/runtime/cli/repl.rs:1220-1225) installs act.sa_sigaction = libc::SIG_DFL instead of the saved onExitSignal. From then on SIGINT kills the process, no bun_restore_stdio runs, and ESC[?2004h stays set; the base never set mode 2004.

• 🟣 src/runtime/cli/repl.rs — pre-existing: after a restart, Up recalls a pasted multi-line entry as several fragments, one per line, instead of the entry. handle_enter adds the entry with its inner LFs to history (src/runtime/cli/repl.rs:2906), History::save writes it as-is, and History::load splits the file on LF (src/runtime/cli/repl.rs:230). Fix: store one entry per record on disk, for example escape LF in save and unescape in load, so that pasted and Multiline-mode entries survive a restart. This PR adds the paste as a new producer of such entries; Multiline mode already produced them on the base.

  Why this was flagged

  A user pastes if (1) {\n x\n} on a raw terminal (Key::Paste, handle_paste at src/runtime/cli/repl.rs:2875) and presses Enter. handle_enter at src/runtime/cli/repl.rs:2906 calls history.add with the entry containing two LFs. History::save at src/runtime/cli/repl.rs:260-264 writes each entry followed by one LF. On the next bun repl, History::load at src/runtime/cli/repl.rs:230 splits the file on LF, so the user gets three entries if (1) {, x, } on Up, and the first is incomplete code that enters Multiline mode. The base branch has the same split for entries typed in Multiline mode; this PR makes a paste a second source of them. No guard in load or save distinguishes an entry boundary from an inner LF.

  Verification: pre-existing. Trigger: any multi-line entry is entered, the session exits and saves history, and a later bun repl loads it. In src/runtime/cli/repl.rs handle_enter line 2906 strips only outer LFs, so inner LFs stay in the entry; History::save lines 261-264 writes each entry with no escaping; History::load line 230 splits on every LF. The base already fails the same way.

[robobun]

Overlap note: this PR also covers the case that #46126 leaves open (stdin a terminal, stdout redirected, a half line, then Ctrl+D twice). No separate PR is open for that case.

stdin_is_line_mode_terminal has no check for a hang-up. The effect differs by platform:

• Linux (kernel 6.1, a pty probe with SIGHUP ignored): a read that is blocked at the hang-up fails with EIO. A read that starts later returns 0 bytes, and tcgetattr(0) then fails with EIO. Nothing runs in either case.
• macOS: not checked. If a hang-up there gives a read of 0 bytes and tcgetattr(0) still succeeds, a half line that one Ctrl+D handed over runs when the terminal goes away.

A test that can show it on the macOS lanes: stdout in a file, SIGHUP ignored, a half line that writes a marker file, one Ctrl+D, then close the pty. Expect no marker file. A possible guard is a zero-timeout poll of fd 0 for POLLHUP, POLLERR and POLLNVAL next to the ICANON check.

[robobun]

Replies to the review findings that are not on a line of the diff. The six inline threads have their own replies.

• SIGINT after an awaited line leaves bracketed paste on. Known, and in the PR notes under "Not covered". After a wait the REPL sets SIGINT to its default action, as on main, so termios stays raw on that route on main too. An earlier version of this PR put back the action from before the wait. It left a stale handler when the awaited line removed its own SIGINT listener, so that change went out again. bun test --parallel, repl: act on a signal at once, and survive its repeat #45756 changes which handler the REPL keeps after a wait, and the reset belongs with that rule.
• A multi-line entry comes back as one entry per line after a restart. This is on main for an entry that was typed over several lines. repl: keep multi-line history entries on one line of the history file #38023 keeps such an entry on one line of the history file. The PR notes now name it.
• Scope warning. bun repl: code repeatly printed when deleting multi-line history code #27560 is not the subject of this PR. It is linked because a paste of several lines needs the multi-row drawing, and that drawing fixes bun repl: code repeatly printed when deleting multi-line history code #27560.

The macOS failures of the first CI run were in the tests: they compared the local flags of the terminal with the kernel's PENDIN state bit in them. 32a1ee4 leaves that bit out of the comparison.

[claude]

I re-reviewed the three commits pushed since my earlier comments and found no new bugs; because this is a large rewrite of the REPL's stdin handling that also adds a write to the exit path of every bun process, a human look is still worthwhile.

What was reviewed:

• The Esc-Esc fix in read_key (third byte is pushed back unless it starts a CSI/SS3 sequence) and the visible_lines viewport in refresh_line plus the height field on Drawing, against the scenarios I raised before.
• The is_incomplete_code change that only treats a top-level control byte as terminating, and the removal of the per-test timeout (the one remaining 15000 in the test file predates this PR).
• reset_active_dec_modes / write_stdout_raw in src/bun_core/tty.rs and its call sites in bun_restore_stdio and Windows restore: the atomic swap-to-zero and the stdout-TTY gate mean it is a no-op unless the REPL set bracketed paste.
• Ctrl+D ending a session from .editor on a line-mode terminal with stdout redirected was examined and judged consistent with how EOF already ended the base REPL, not a regression.

Extended reasoning...

The PR replaces the REPL's single byte-as-key stdin reader with two paths (raw-terminal key reading with bracketed-paste support, and line-of-text reading for pipes, files and non-raw terminals), rewrites CSI parsing, adds a display form for control bytes and multi-line entries, and registers a DEC-mode reset table in bun_core::tty that bun_restore_stdio calls on every process exit and from the signal handler. It touches no auth, crypto or network surface; the untrusted-input surface is stdin bytes and terminal escape sequences, which the new parser bounds (64-byte CSI parameter limit, pushback of one byte). Since my prior review the author pushed commits that address the tall-entry redraw, the Esc-Esc lost key, the control-byte-in-bracket SyntaxError and the test timeout, and I verified each in the code. The remaining reasons for a human look are the size (+2152/-165, 745 lines changed in repl.rs with unix/windows cfg branches), the exit-path hook that affects every bun process, and the behavior decisions the author explicitly leaves to a maintainer (paste runs as one entry on Enter, .editor on a pipe).