view rust/hg-core/src/revlog/changelog.rs @ 46243:63c923fd7fa8

setup: when possible, build and bundle man pages

This makes it so the manual pages are built as part of the Python
build, and includes them in any wheel generated. This should make
Python wheels a much more useful and complete way of distributing
Mercurial binaries.

Differential Revision: https://phab.mercurial-scm.org/D9640

use crate::repo::Repo;
use crate::revlog::revlog::{Revlog, RevlogError};
use crate::revlog::NodePrefixRef;
use crate::revlog::Revision;

/// A specialized `Revlog` to work with `changelog` data format.
pub struct Changelog {
    /// The generic `revlog` format.
    revlog: Revlog,
}

impl Changelog {
    /// Open the `changelog` of a repository given by its root.
    pub fn open(repo: &Repo) -> Result<Self, RevlogError> {
        let revlog = Revlog::open(repo, "00changelog.i", None)?;
        Ok(Self { revlog })
    }

    /// Return the `ChangelogEntry` a given node id.
    pub fn get_node(
        &self,
        node: NodePrefixRef,
    ) -> Result<ChangelogEntry, RevlogError> {
        let rev = self.revlog.get_node_rev(node)?;
        self.get_rev(rev)
    }

    /// Return the `ChangelogEntry` of a given node revision.
    pub fn get_rev(
        &self,
        rev: Revision,
    ) -> Result<ChangelogEntry, RevlogError> {
        let bytes = self.revlog.get_rev_data(rev)?;
        Ok(ChangelogEntry { bytes })
    }
}

/// `Changelog` entry which knows how to interpret the `changelog` data bytes.
#[derive(Debug)]
pub struct ChangelogEntry {
    /// The data bytes of the `changelog` entry.
    bytes: Vec<u8>,
}

impl ChangelogEntry {
    /// Return an iterator over the lines of the entry.
    pub fn lines(&self) -> impl Iterator<Item = &[u8]> {
        self.bytes
            .split(|b| b == &b'\n')
            .filter(|line| !line.is_empty())
    }

    /// Return the node id of the `manifest` referenced by this `changelog`
    /// entry.
    pub fn manifest_node(&self) -> Result<&[u8], RevlogError> {
        self.lines().next().ok_or(RevlogError::Corrupted)
    }
}