view rust/hg-core/src/exit_codes.rs @ 48846:006688e36e12 stable

rhg: use `Command::exec` instead of `Command::status`

`rhg` is supposed to be a transparent executable, using a subprocess defeats
that purpose. See inline comments for more details.

This also introduces the `which` crate to check if the fallback executable
actually exists to help debugging (plain `execve` doesn't give much
information).

The error code 253 is used to signify that the fallback is not found, but may
mean in the future that it is otherwise invalid if we start being more
specific.

Differential Revision: https://phab.mercurial-scm.org/D12578

pub type ExitCode = i32;

/// Successful exit
pub const OK: ExitCode = 0;

/// Generic abort
pub const ABORT: ExitCode = 255;

// Abort when there is a config related error
pub const CONFIG_ERROR_ABORT: ExitCode = 30;

// Abort when there is an error while parsing config
pub const CONFIG_PARSE_ERROR_ABORT: ExitCode = 10;

/// Generic something completed but did not succeed
pub const UNSUCCESSFUL: ExitCode = 1;

/// Command or feature not implemented by rhg
pub const UNIMPLEMENTED: ExitCode = 252;

/// The fallback path is not valid
pub const INVALID_FALLBACK: ExitCode = 253;