annotate rust/hg-core/src/lib.rs @ 44528:c8891bca40fb

rust-status: add bare `hg status` support in hg-core

A lot of performance remains to be gained, most notably by doing more things
in parallel, but also by caching, not falling back to Python but switching
to another regex engine, etc..

I have measured on multiple repositories that this change, when in combination
with the next two patches, improve bare `hg status` performance, and has no
observable impact when falling back (because it does so early).

On the Netbeans repository:
C: 840ms
Rust+C: 556ms

Mozilla Central with the one pattern that causes a fallback removed:
C: 2.315s
Rust+C: 1.700 s

Differential Revision: https://phab.mercurial-scm.org/D7929

// Copyright 2018-2020 Georges Racinet <[e-mail]>
//           and Mercurial contributors
//
// This software may be used and distributed according to the terms of the
// GNU General Public License version 2 or any later version.
mod ancestors;
pub mod dagops;
pub use ancestors::{AncestorsIterator, LazyAncestors, MissingAncestors};
mod dirstate;
pub mod discovery;
pub mod testing; // unconditionally built, for use from integration tests
pub use dirstate::{
    dirs_multiset::{DirsMultiset, DirsMultisetIter},
    dirstate_map::DirstateMap,
    parsers::{pack_dirstate, parse_dirstate, PARENT_SIZE},
    status::{
        status, BadMatch, BadType, DirstateStatus, StatusError, StatusOptions,
    },
    CopyMap, CopyMapIter, DirstateEntry, DirstateParents, EntryState,
    StateMap, StateMapIter,
};
mod filepatterns;
pub mod matchers;
pub mod revlog;
pub use revlog::*;
#[cfg(feature = "with-re2")]
pub mod re2;
pub mod utils;

use crate::utils::hg_path::{HgPathBuf, HgPathError};
pub use filepatterns::{
    parse_pattern_syntax, read_pattern_file, IgnorePattern,
    PatternFileWarning, PatternSyntax,
};
use std::collections::HashMap;
use twox_hash::RandomXxHashBuilder64;

pub type LineNumber = usize;

/// Rust's default hasher is too slow because it tries to prevent collision
/// attacks. We are not concerned about those: if an ill-minded person has
/// write access to your repository, you have other issues.
pub type FastHashMap<K, V> = HashMap<K, V, RandomXxHashBuilder64>;

#[derive(Clone, Debug, PartialEq)]
pub enum DirstateParseError {
    TooLittleData,
    Overflow,
    CorruptedEntry(String),
    Damaged,
}

impl From<std::io::Error> for DirstateParseError {
    fn from(e: std::io::Error) -> Self {
        DirstateParseError::CorruptedEntry(e.to_string())
    }
}

impl ToString for DirstateParseError {
    fn to_string(&self) -> String {
        use crate::DirstateParseError::*;
        match self {
            TooLittleData => "Too little data for dirstate.".to_string(),
            Overflow => "Overflow in dirstate.".to_string(),
            CorruptedEntry(e) => format!("Corrupted entry: {:?}.", e),
            Damaged => "Dirstate appears to be damaged.".to_string(),
        }
    }
}

#[derive(Debug, PartialEq)]
pub enum DirstatePackError {
    CorruptedEntry(String),
    CorruptedParent,
    BadSize(usize, usize),
}

impl From<std::io::Error> for DirstatePackError {
    fn from(e: std::io::Error) -> Self {
        DirstatePackError::CorruptedEntry(e.to_string())
    }
}
#[derive(Debug, PartialEq)]
pub enum DirstateMapError {
    PathNotFound(HgPathBuf),
    EmptyPath,
    InvalidPath(HgPathError),
}

impl ToString for DirstateMapError {
    fn to_string(&self) -> String {
        match self {
            DirstateMapError::PathNotFound(_) => {
                "expected a value, found none".to_string()
            }
            DirstateMapError::EmptyPath => "Overflow in dirstate.".to_string(),
            DirstateMapError::InvalidPath(e) => e.to_string(),
        }
    }
}

pub enum DirstateError {
    Parse(DirstateParseError),
    Pack(DirstatePackError),
    Map(DirstateMapError),
    IO(std::io::Error),
}

impl From<DirstateParseError> for DirstateError {
    fn from(e: DirstateParseError) -> Self {
        DirstateError::Parse(e)
    }
}

impl From<DirstatePackError> for DirstateError {
    fn from(e: DirstatePackError) -> Self {
        DirstateError::Pack(e)
    }
}

#[derive(Debug)]
pub enum PatternError {
    Path(HgPathError),
    UnsupportedSyntax(String),
    UnsupportedSyntaxInFile(String, String, usize),
    TooLong(usize),
    IO(std::io::Error),
    /// Needed a pattern that can be turned into a regex but got one that
    /// can't. This should only happen through programmer error.
    NonRegexPattern(IgnorePattern),
    /// This is temporary, see `re2/mod.rs`.
    /// This will cause a fallback to Python.
    Re2NotInstalled,
}

impl ToString for PatternError {
    fn to_string(&self) -> String {
        match self {
            PatternError::UnsupportedSyntax(syntax) => {
                format!("Unsupported syntax {}", syntax)
            }
            PatternError::UnsupportedSyntaxInFile(syntax, file_path, line) => {
                format!(
                    "{}:{}: unsupported syntax {}",
                    file_path, line, syntax
                )
            }
            PatternError::TooLong(size) => {
                format!("matcher pattern is too long ({} bytes)", size)
            }
            PatternError::IO(e) => e.to_string(),
            PatternError::Path(e) => e.to_string(),
            PatternError::NonRegexPattern(pattern) => {
                format!("'{:?}' cannot be turned into a regex", pattern)
            }
            PatternError::Re2NotInstalled => {
                "Re2 is not installed, cannot use regex functionality."
                    .to_string()
            }
        }
    }
}

impl From<DirstateMapError> for DirstateError {
    fn from(e: DirstateMapError) -> Self {
        DirstateError::Map(e)
    }
}

impl From<std::io::Error> for DirstateError {
    fn from(e: std::io::Error) -> Self {
        DirstateError::IO(e)
    }
}

impl From<std::io::Error> for PatternError {
    fn from(e: std::io::Error) -> Self {
        PatternError::IO(e)
    }
}

impl From<HgPathError> for PatternError {
    fn from(e: HgPathError) -> Self {
        PatternError::Path(e)
    }
}