view rust/hg-cpython/src/lib.rs @ 44202:a7f8160cc4e4

setup: don't skip the search for global hg.exe if there is no local instance

The point of trying not to blindly execute `hg` on Windows is that the local
hg.exe would be given precedence, and if py3 isn't on PATH, it errors out with a
modal dialog.  But that's not a problem if there is no local executable that
could be run.

The problem that I recently ran into was I upgraded the repo format to use zstd.
But doing a `make clean` deletes all of the supporting libraries, causing the
next run to abort with a message about not understanding the
`revlog-compression-zstd` requirement.  By getting rid of the local executable
in the previous commit when cleaning, we avoid leaving a broken executable
around, and avoid the py3 PATH problem too.  There is still a small hole in that
`hg.exe` needs to be deleted before switching between py2/py3/PyOxidizer builds,
because the zstd module won't load.  But that seems like good hygiene anyway.

Differential Revision: https://phab.mercurial-scm.org/D8038

// lib.rs
//
// Copyright 2018 Georges Racinet <[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.

//! Python bindings of `hg-core` objects using the `cpython` crate.
//! Once compiled, the resulting single shared library object can be placed in
//! the `mercurial` package directly as `rustext.so` or `rustext.dll`.
//! It holds several modules, so that from the point of view of Python,
//! it behaves as the `cext` package.
//!
//! Example:
//!
//! ```text
//! >>> from mercurial.rustext import ancestor
//! >>> ancestor.__doc__
//! 'Generic DAG ancestor algorithms - Rust implementation'
//! ```

/// This crate uses nested private macros, `extern crate` is still needed in
/// 2018 edition.
#[macro_use]
extern crate cpython;

pub mod ancestors;
mod cindex;
mod conversion;
#[macro_use]
pub mod ref_sharing;
pub mod dagops;
pub mod dirstate;
pub mod discovery;
pub mod exceptions;
pub mod parsers;
pub mod revlog;
pub mod utils;

py_module_initializer!(rustext, initrustext, PyInit_rustext, |py, m| {
    m.add(
        py,
        "__doc__",
        "Mercurial core concepts - Rust implementation",
    )?;

    let dotted_name: String = m.get(py, "__name__")?.extract(py)?;
    m.add(py, "ancestor", ancestors::init_module(py, &dotted_name)?)?;
    m.add(py, "dagop", dagops::init_module(py, &dotted_name)?)?;
    m.add(py, "discovery", discovery::init_module(py, &dotted_name)?)?;
    m.add(py, "dirstate", dirstate::init_module(py, &dotted_name)?)?;
    m.add(py, "revlog", revlog::init_module(py, &dotted_name)?)?;
    m.add(
        py,
        "parsers",
        parsers::init_parsers_module(py, &dotted_name)?,
    )?;
    m.add(py, "GraphError", py.get_type::<exceptions::GraphError>())?;
    Ok(())
});

#[cfg(not(any(feature = "python27-bin", feature = "python3-bin")))]
#[test]
#[ignore]
fn libpython_must_be_linked_to_run_tests() {
    // stub function to tell that some tests wouldn't run
}