view rust/rhg/src/commands/root.rs @ 45381:47997afadf08

rhg: ask the error message from `CommandError`

Avoid repeating the display of the same error messages in different commands.

Differential Revision: https://phab.mercurial-scm.org/D8865

use crate::commands::Command;
use crate::error::{CommandError, CommandErrorKind};
use crate::ui::Ui;
use hg::operations::{FindRoot, FindRootErrorKind};
use hg::utils::files::get_bytes_from_path;

pub const HELP_TEXT: &str = "
Print the root directory of the current repository.

Returns 0 on success.
";

pub struct RootCommand<'a> {
    ui: &'a Ui,
}

impl<'a> RootCommand<'a> {
    pub fn new(ui: &'a Ui) -> Self {
        RootCommand { ui }
    }
}

impl<'a> Command<'a> for RootCommand<'a> {
    fn run(&self) -> Result<(), CommandError> {
        let path_buf =
            FindRoot::new().run().map_err(|err| match err.kind {
                FindRootErrorKind::RootNotFound(path) => {
                    CommandErrorKind::RootNotFound(path)
                }
                FindRootErrorKind::GetCurrentDirError(e) => {
                    CommandErrorKind::CurrentDirNotFound(e)
                }
            })?;

        let bytes = get_bytes_from_path(path_buf);

        // TODO use formating macro
        self.ui.write_stdout(&[bytes.as_slice(), b"\n"].concat())?;

        Ok(())
    }
}