## Summary
This PR extends the `always_allow` tool permission patterns to work with
Nushell, Elvish, and Rc shells. Previously, these shells were
incorrectly excluded because they don't use `&&`/`||` operators for
command chaining. However, brush-parser can safely parse their command
syntax since they all use `;` for sequential execution.
## Changes
- Add `ShellKind::Nushell`, `ShellKind::Elvish`, and `ShellKind::Rc` to
`supports_posix_chaining()`
- Split `ShellKind::Unknown` into `ShellKind::UnknownWindows` and
`ShellKind::UnknownUnix` to preserve platform-specific fallback behavior
while still denying `always_allow` patterns for unrecognized shells
- Add comprehensive tests for the new shell support
- Clarify documentation about shell compatibility
## Shell Notes
- **Nushell**: Uses `;` for sequential execution. The `and`/`or`
keywords are boolean operators on values, not command chaining.
- **Elvish**: Uses `;` to separate pipelines. Does not have `&&` or `||`
operators. Its `and`/`or` are special commands operating on values.
- **Rc (Plan 9)**: Uses `;` for sequential execution and `|` for piping.
Does not have `&&`/`||` operators.
## Security
Unknown shells still return `false` from `supports_posix_chaining()`, so
`always_allow` patterns are denied for safety when we can't verify the
shell's syntax.
(No release notes because granular tool permissions are still
feature-flagged.)
Release Notes:
- N/A
---------
Co-authored-by: Zed Zippy <234243425+zed-zippy[bot]@users.noreply.github.com>
Closes#45211
This ensures that all sub-processes that were launched by the ACP server
are terminated. One scenario where this is easily reproducible:
- Start a new Claude Code ACP session
- Submit a prompt
- While Claude-code is still responding, start a new session
- The `claude-code` subprocess is leaked from the previous session (The
Claude-code SDK runs the Claude-code binary in a sub process)
This PR fixes this by using process groups on Unix.
It does not fix the process leaks on Windows yet (will follow up with
another PR)
Release Notes:
- Fixed an issue where subprocesses of ACP servers could be leaked after
starting a new session
Using `shlex` unconditionally is dangerous as it assumes the underlying
shell is POSIX which is not the case for PowerShell, CMD, or Nushell.
Therefore, whenever we want to quote the args we should utilise our
helper `util::shell::ShellKind::try_quote` which takes into account
which shell is being used to actually exec/spawn the invocation.
Release Notes:
- N/A
---------
Co-authored-by: Lukas Wirth <me@lukaswirth.dev>
Joseph T. Lyons