nushell/crates/nu-system
nome a948ec6c2c
Fix handling of stopped TUI applications on unix (#13741)
# Description

Instead of handling a foreground process being stopped in any way, we
were simply ignoring SIGTSTP (which the terminal usually sends to the
foreground process group when Ctrl-Z is pressed), and propagating this
to our foreground children. This works for most processes, but it
generally fails for applications which put the terminal in raw mode[1]
and implement their own suspension mechanism (typically TUI apps like
helix[2], neovim[3], top[4] or amp[5]). In these cases, triggering
suspension within the app results in the terminal getting blocked, since
the application is waiting for a SIGCONT, while nushell is waiting for
it to exit.

Fix this by unblocking SIGTSTP for our foreground children (neovim,
helix and probably others send this to themselves while trying to
suspend), and displaying the following message whenever one of them gets
stopped:

    nushell currently does not support background jobs
    press any key to continue

Pressing any key will then send SIGCONT to the child's process group and
resume waiting.

This fix is probably going to be superseded by a proper background job
implementation (#247) at some point, but for now it's better than
completely blocking the terminal.

[1]
https://docs.rs/crossterm/latest/crossterm/terminal/index.html#raw-mode
[2] https://helix-editor.com/
[3] https://neovim.io/
[4] https://man7.org/linux/man-pages/man1/top.1.html
[5] https://amp.rs/

- fixes #1038
- fixes #7335
- fixes #10335

# User-Facing Changes

While any foreground process is running, Ctrl-Z is no longer ignored.
Instead, the message described above is displayed, and nushell waits for
a key to be pressed.

# Tests + Formatting

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# After Submitting
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2024-09-24 06:44:58 -05:00
..
examples Reduce again the number of match calls (#7815) 2023-01-24 12:23:42 +01:00
src Fix handling of stopped TUI applications on unix (#13741) 2024-09-24 06:44:58 -05:00
.gitignore Add nu-system and rewrite ps command (#734) 2022-01-14 17:20:53 +11:00
Cargo.toml Bump version to 0.98.1 (#13896) 2024-09-22 12:41:44 +08:00
LICENSE Nu glob (#4818) 2022-03-13 11:30:27 -07:00
README.md Add top-level crate documentation/READMEs (#12907) 2024-07-14 10:10:41 +02:00

Operating system specific bindings used by Nushell.

Currently primarily wrappers around processes and ways to gather process info from the system

Internal Nushell crate

This crate implements components of Nushell and is not designed to support plugin authors or other users directly.