ctrl+c of repl task exits the repl entirely

[thegu5]

I have confirmed that this is a bug related to nh

• This is a bug, and not an user error or a support request. I understand that my issue will be closed if it is not a bug in NH.
• I have checked the issues tab and confirmed that my issue has not yet been reported. I understand that my issue will be closed if it is a duplicate.

Description

When cancelling a long running task in a repl launched via nh os repl, the repl is exited entirely instead of just cancelling the task.

$ nh os repl                                                                                                                                                                                                1358ms
Nix 2.31.2
Type :? for help.
Loading installable 'git+file:///home/gu5/Documents/git/nix-config#nixosConfigurations.enth'...
Added 11 variables.
_module, _type, class, config, extendModules, extraArgs, graph, lib, options, pkgs, type
nix-repl> pkgs
{
  AAAAAASomeThingsFailToEvaluate = «error: This pseudo-package is likely not the only part of Nixpkgs that fails to evaluate.
You should not evaluate entire Nixpkgs without measures to handle failing packages.
»;
  AMB-plugins = «derivation /nix/store/2x7yz3gavrqlx7q2n5qvf6fjxar52d4j-AMB-plugins-0.8.1.drv»;
error: interrupted by the user

Failed tcsetattr(TCSADRAIN): Input/output error
nix-repl> Failed tcsetattr(TCSADRAIN): Input/output error
$ # back at the shell prompt

vs

nix repl
Nix 2.31.2
Type :? for help.
nix-repl> import <nixpkgs> { }
{
  AAAAAASomeThingsFailToEvaluate = «error: This pseudo-package is likely not the only part of Nixpkgs that fails to evaluate.
You should not evaluate entire Nixpkgs without measures to handle failing packages.
»;
  AMB-plugins = «derivation /nix/store/2x7yz3gavrqlx7q2n5qvf6fjxar52d4j-AMB-plugins-0.8.1.drv»;
error: interrupted by the user

nix-repl> # still in the repl

Installation Method

Stable Release (nixpkgs, pkgs.nh from nixos-unstable or nixos-yy-mm)

Installation Method (Other)

No response

NH Version

v4.2.0

System Information

• system: "x86_64-linux"
• host os: Linux 6.12.58, NixOS, 26.05 (Yarara), 26.05.20251127.2fad6ea
• multi-user?: yes
• sandbox: yes
• version: nix-env (Nix) 2.31.2
• nixpkgs: /nix/store/fqyqwsw82v7jr6ncgrrg7cama5sl577r-source