rust/hg-core/build.rs

phabricator: extract the logic to amend diff properties to a function

This will be needed on a separate code path when dealing with folding revisions.
And since we know that will involve adding multiple local commmits to the diff
properties instead of just one, restructure the logic slightly to allow it.

Differential Revision: https://phab.mercurial-scm.org/D8312

// build.rs
//
// Copyright 2020 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.

#[cfg(feature = "with-re2")]
use cc;

#[cfg(feature = "with-re2")]
fn compile_re2() {
    cc::Build::new()
        .cpp(true)
        .flag("-std=c++11")
        .file("src/re2/rust_re2.cpp")
        .compile("librustre.a");

    println!("cargo:rustc-link-lib=re2");
}

fn main() {
    #[cfg(feature = "with-re2")]
    compile_re2();
}