view rust/hg-cpython/src/dirstate/status.rs @ 47385:f6bb181c75f8

rust: Parse "subinclude"d files along the way, not later

When parsing a `.hgignore` file and encountering an `include:` line,
the included file is parsed recursively right then in a depth-first fashion.

With `subinclude:` however included files were parsed (recursively) much later.
This changes it to be expanded during parsing, like `.hgignore`.

The motivation for this is an upcoming changeset that needs to detect changes
in which files are ignored or not. The plan is to hash all ignore files while
they are being read, and store that hash in the dirstate (in v2 format).
In order to allow a potential alternative implementations to read that format,
the algorithm to compute that hash must be documented. Having a well-defined
depth-first ordering for the tree of (sub-)included files makes that easier.

Differential Revision: https://phab.mercurial-scm.org/D10834

// status.rs
//
// Copyright 2019, Raphaël Gomès <[e-mail]>
//
// This software may be used and distributed according to the terms of the
// GNU General Public License version 2 or any later version.

//! Bindings for the `hg::status` module provided by the
//! `hg-core` crate. From Python, this will be seen as
//! `rustext.dirstate.status`.

use crate::{dirstate::DirstateMap, exceptions::FallbackError};
use cpython::exc::OSError;
use cpython::{
    exc::ValueError, ObjectProtocol, PyBytes, PyErr, PyList, PyObject,
    PyResult, PyTuple, Python, PythonObject, ToPyObject,
};
use hg::{
    matchers::{AlwaysMatcher, FileMatcher, IncludeMatcher},
    parse_pattern_syntax,
    utils::{
        files::{get_bytes_from_path, get_path_from_bytes},
        hg_path::{HgPath, HgPathBuf},
    },
    BadMatch, DirstateStatus, IgnorePattern, PatternFileWarning, StatusError,
    StatusOptions,
};
use std::borrow::Borrow;

/// This will be useless once trait impls for collection are added to `PyBytes`
/// upstream.
fn collect_pybytes_list(
    py: Python,
    collection: &[impl AsRef<HgPath>],
) -> PyList {
    let list = PyList::new(py, &[]);

    for path in collection.iter() {
        list.append(
            py,
            PyBytes::new(py, path.as_ref().as_bytes()).into_object(),
        )
    }

    list
}

fn collect_bad_matches(
    py: Python,
    collection: &[(impl AsRef<HgPath>, BadMatch)],
) -> PyResult<PyList> {
    let list = PyList::new(py, &[]);

    let os = py.import("os")?;
    let get_error_message = |code: i32| -> PyResult<_> {
        os.call(
            py,
            "strerror",
            PyTuple::new(py, &[code.to_py_object(py).into_object()]),
            None,
        )
    };

    for (path, bad_match) in collection.iter() {
        let message = match bad_match {
            BadMatch::OsError(code) => get_error_message(*code)?,
            BadMatch::BadType(bad_type) => format!(
                "unsupported file type (type is {})",
                bad_type.to_string()
            )
            .to_py_object(py)
            .into_object(),
        };
        list.append(
            py,
            (PyBytes::new(py, path.as_ref().as_bytes()), message)
                .to_py_object(py)
                .into_object(),
        )
    }

    Ok(list)
}

fn handle_fallback(py: Python, err: StatusError) -> PyErr {
    match err {
        StatusError::Pattern(e) => {
            let as_string = e.to_string();
            log::trace!("Rust status fallback: `{}`", &as_string);

            PyErr::new::<FallbackError, _>(py, &as_string)
        }
        StatusError::IO(e) => PyErr::new::<OSError, _>(py, e.to_string()),
        e => PyErr::new::<ValueError, _>(py, e.to_string()),
    }
}

pub fn status_wrapper(
    py: Python,
    dmap: DirstateMap,
    matcher: PyObject,
    root_dir: PyObject,
    ignore_files: PyList,
    check_exec: bool,
    last_normal_time: i64,
    list_clean: bool,
    list_ignored: bool,
    list_unknown: bool,
    collect_traversed_dirs: bool,
) -> PyResult<PyTuple> {
    let bytes = root_dir.extract::<PyBytes>(py)?;
    let root_dir = get_path_from_bytes(bytes.data(py));

    let dmap: DirstateMap = dmap.to_py_object(py);
    let mut dmap = dmap.get_inner_mut(py);

    let ignore_files: PyResult<Vec<_>> = ignore_files
        .iter(py)
        .map(|b| {
            let file = b.extract::<PyBytes>(py)?;
            Ok(get_path_from_bytes(file.data(py)).to_owned())
        })
        .collect();
    let ignore_files = ignore_files?;

    match matcher.get_type(py).name(py).borrow() {
        "alwaysmatcher" => {
            let matcher = AlwaysMatcher;
            let (status_res, warnings) = dmap
                .status(
                    &matcher,
                    root_dir.to_path_buf(),
                    ignore_files,
                    StatusOptions {
                        check_exec,
                        last_normal_time,
                        list_clean,
                        list_ignored,
                        list_unknown,
                        collect_traversed_dirs,
                    },
                )
                .map_err(|e| handle_fallback(py, e))?;
            build_response(py, status_res, warnings)
        }
        "exactmatcher" => {
            let files = matcher.call_method(
                py,
                "files",
                PyTuple::new(py, &[]),
                None,
            )?;
            let files: PyList = files.cast_into(py)?;
            let files: PyResult<Vec<HgPathBuf>> = files
                .iter(py)
                .map(|f| {
                    Ok(HgPathBuf::from_bytes(
                        f.extract::<PyBytes>(py)?.data(py),
                    ))
                })
                .collect();

            let files = files?;
            let matcher = FileMatcher::new(files.as_ref())
                .map_err(|e| PyErr::new::<ValueError, _>(py, e.to_string()))?;
            let (status_res, warnings) = dmap
                .status(
                    &matcher,
                    root_dir.to_path_buf(),
                    ignore_files,
                    StatusOptions {
                        check_exec,
                        last_normal_time,
                        list_clean,
                        list_ignored,
                        list_unknown,
                        collect_traversed_dirs,
                    },
                )
                .map_err(|e| handle_fallback(py, e))?;
            build_response(py, status_res, warnings)
        }
        "includematcher" => {
            // Get the patterns from Python even though most of them are
            // redundant with those we will parse later on, as they include
            // those passed from the command line.
            let ignore_patterns: PyResult<Vec<_>> = matcher
                .getattr(py, "_kindpats")?
                .iter(py)?
                .map(|k| {
                    let k = k?;
                    let syntax = parse_pattern_syntax(
                        &[
                            k.get_item(py, 0)?
                                .extract::<PyBytes>(py)?
                                .data(py),
                            &b":"[..],
                        ]
                        .concat(),
                    )
                    .map_err(|e| {
                        handle_fallback(py, StatusError::Pattern(e))
                    })?;
                    let pattern = k.get_item(py, 1)?.extract::<PyBytes>(py)?;
                    let pattern = pattern.data(py);
                    let source = k.get_item(py, 2)?.extract::<PyBytes>(py)?;
                    let source = get_path_from_bytes(source.data(py));
                    let new = IgnorePattern::new(syntax, pattern, source);
                    Ok(new)
                })
                .collect();

            let ignore_patterns = ignore_patterns?;

            let matcher = IncludeMatcher::new(ignore_patterns)
                .map_err(|e| handle_fallback(py, e.into()))?;

            let (status_res, warnings) = dmap
                .status(
                    &matcher,
                    root_dir.to_path_buf(),
                    ignore_files,
                    StatusOptions {
                        check_exec,
                        last_normal_time,
                        list_clean,
                        list_ignored,
                        list_unknown,
                        collect_traversed_dirs,
                    },
                )
                .map_err(|e| handle_fallback(py, e))?;

            build_response(py, status_res, warnings)
        }
        e => Err(PyErr::new::<ValueError, _>(
            py,
            format!("Unsupported matcher {}", e),
        )),
    }
}

fn build_response(
    py: Python,
    status_res: DirstateStatus,
    warnings: Vec<PatternFileWarning>,
) -> PyResult<PyTuple> {
    let modified = collect_pybytes_list(py, status_res.modified.as_ref());
    let added = collect_pybytes_list(py, status_res.added.as_ref());
    let removed = collect_pybytes_list(py, status_res.removed.as_ref());
    let deleted = collect_pybytes_list(py, status_res.deleted.as_ref());
    let clean = collect_pybytes_list(py, status_res.clean.as_ref());
    let ignored = collect_pybytes_list(py, status_res.ignored.as_ref());
    let unknown = collect_pybytes_list(py, status_res.unknown.as_ref());
    let unsure = collect_pybytes_list(py, status_res.unsure.as_ref());
    let bad = collect_bad_matches(py, status_res.bad.as_ref())?;
    let traversed = collect_pybytes_list(py, status_res.traversed.as_ref());
    let dirty = status_res.dirty.to_py_object(py);
    let py_warnings = PyList::new(py, &[]);
    for warning in warnings.iter() {
        // We use duck-typing on the Python side for dispatch, good enough for
        // now.
        match warning {
            PatternFileWarning::InvalidSyntax(file, syn) => {
                py_warnings.append(
                    py,
                    (
                        PyBytes::new(py, &get_bytes_from_path(&file)),
                        PyBytes::new(py, syn),
                    )
                        .to_py_object(py)
                        .into_object(),
                );
            }
            PatternFileWarning::NoSuchFile(file) => py_warnings.append(
                py,
                PyBytes::new(py, &get_bytes_from_path(&file)).into_object(),
            ),
        }
    }

    Ok(PyTuple::new(
        py,
        &[
            unsure.into_object(),
            modified.into_object(),
            added.into_object(),
            removed.into_object(),
            deleted.into_object(),
            clean.into_object(),
            ignored.into_object(),
            unknown.into_object(),
            py_warnings.into_object(),
            bad.into_object(),
            traversed.into_object(),
            dirty.into_object(),
        ][..],
    ))
}