comparison rust/chg/src/message.rs @ 44679:82adc720c0a3

rust-chg: add helper to parse instructions sent from server

This is well structured version of runinstructions() of chg.c.

Differential Revision: https://phab.mercurial-scm.org/D8378

44678:806f1f1ba430

use bytes::{BufMut, Bytes, BytesMut};
use std::error;
use std::ffi::{OsStr, OsString};
use std::io;
use std::os::unix::ffi::OsStrExt;

pub use tokio_hglib::message::*; // re-exports

/// Shell command type requested by the server.
#[derive(Clone, Copy, Debug, Eq, PartialEq)]

        _ => Err(new_parse_error(format!(
            "unknown command type: {}",
            decode_latin1(value)
        ))),
    }
}

// allocate large buffer as environment variables can be quite long
const INITIAL_PACKED_ENV_VARS_CAPACITY: usize = 4096;

    fn parse_command_spec_unknown_type() {
        assert!(parse_command_spec(Bytes::from_static(b"paper\0less")).is_err());
    }

    #[test]
    fn pack_env_vars_os_good() {
        assert_eq!(
            pack_env_vars_os(vec![] as Vec<(OsString, OsString)>),
            Bytes::new()
        );

    }

    fn os_string_pair_from(k: &[u8], v: &[u8]) -> (OsString, OsString) {
        (os_string_from(k), os_string_from(v))
    }
}

44679:82adc720c0a3

use bytes::{BufMut, Bytes, BytesMut};
use std::error;
use std::ffi::{OsStr, OsString};
use std::io;
use std::os::unix::ffi::OsStrExt;
use std::path::PathBuf;

pub use tokio_hglib::message::*; // re-exports

/// Shell command type requested by the server.
#[derive(Clone, Copy, Debug, Eq, PartialEq)]

        _ => Err(new_parse_error(format!(
            "unknown command type: {}",
            decode_latin1(value)
        ))),
    }
}

/// Client-side instruction requested by the server.
#[derive(Clone, Debug, Eq, PartialEq)]
pub enum Instruction {
    Exit(i32),
    Reconnect,
    Redirect(PathBuf),
    Unlink(PathBuf),
}

/// Parses validation result into instructions.
pub fn parse_instructions(data: Bytes) -> io::Result<Vec<Instruction>> {
    let mut instructions = Vec::new();
    for l in data.split(|&c| c == b'\0') {
        if l.is_empty() {
            continue;
        }
        let mut s = l.splitn(2, |&c| c == b' ');
        let inst = match (s.next().unwrap(), s.next()) {
            (b"exit", Some(arg)) => decode_latin1(arg)
                .parse()
                .map(Instruction::Exit)
                .map_err(|_| new_parse_error(format!("invalid exit code: {:?}", arg)))?,
            (b"reconnect", None) => Instruction::Reconnect,
            (b"redirect", Some(arg)) => {
                Instruction::Redirect(OsStr::from_bytes(arg).to_owned().into())
            }
            (b"unlink", Some(arg)) => Instruction::Unlink(OsStr::from_bytes(arg).to_owned().into()),
            _ => {
                return Err(new_parse_error(format!("unknown command: {:?}", l)));
            }
        };
        instructions.push(inst);
    }
    Ok(instructions)
}

// allocate large buffer as environment variables can be quite long
const INITIAL_PACKED_ENV_VARS_CAPACITY: usize = 4096;

    fn parse_command_spec_unknown_type() {
        assert!(parse_command_spec(Bytes::from_static(b"paper\0less")).is_err());
    }

    #[test]
    fn parse_instructions_good() {
        let src = [
            b"exit 123".as_ref(),
            b"reconnect".as_ref(),
            b"redirect /whatever".as_ref(),
            b"unlink /someother".as_ref(),
        ]
        .join(&0);
        let insts = vec![
            Instruction::Exit(123),
            Instruction::Reconnect,
            Instruction::Redirect(path_buf_from(b"/whatever")),
            Instruction::Unlink(path_buf_from(b"/someother")),
        ];
        assert_eq!(parse_instructions(Bytes::from(src)).unwrap(), insts);
    }

    #[test]
    fn parse_instructions_empty() {
        assert_eq!(parse_instructions(Bytes::new()).unwrap(), vec![]);
        assert_eq!(
            parse_instructions(Bytes::from_static(b"\0")).unwrap(),
            vec![]
        );
    }

    #[test]
    fn parse_instructions_malformed_exit_code() {
        assert!(parse_instructions(Bytes::from_static(b"exit foo")).is_err());
    }

    #[test]
    fn parse_instructions_missing_argument() {
        assert!(parse_instructions(Bytes::from_static(b"exit")).is_err());
        assert!(parse_instructions(Bytes::from_static(b"redirect")).is_err());
        assert!(parse_instructions(Bytes::from_static(b"unlink")).is_err());
    }

    #[test]
    fn parse_instructions_unknown_command() {
        assert!(parse_instructions(Bytes::from_static(b"quit 0")).is_err());
    }

    #[test]
    fn pack_env_vars_os_good() {
        assert_eq!(
            pack_env_vars_os(vec![] as Vec<(OsString, OsString)>),
            Bytes::new()
        );

    }

    fn os_string_pair_from(k: &[u8], v: &[u8]) -> (OsString, OsString) {
        (os_string_from(k), os_string_from(v))
    }

    fn path_buf_from(s: &[u8]) -> PathBuf {
        os_string_from(s).into()
    }
}