rust/hgcli/build.rs

packaging: add dependencies to the PyOxidizer build on macOS

Otherwise, we get a bunch of test failures for missing things like pygments, or
tests skipped entirely.  The input file is a copy/paste from the equivalent
Windows file, but with dulwich, pygit2, and pytest-vcr commented out because
the build process errors out with them, flagging them as incompatible with
loading from memory.  I have no idea if that's actually true or not, because
I've noticed that if I don't `make clean` after every build, the next build
flags the watchman stuff as incompatible with loading from memory.

The remaining failures are:

    Failed test-alias.t: output changed
    Failed test-basic.t: output changed
    Failed test-check-help.t: output changed
    Failed test-commit-interactive.t: output changed
    Failed test-extension.t: output changed
    Failed test-help.t: output changed
    Failed test-i18n.t: output changed
    Failed test-log.t: output changed
    Failed test-qrecord.t: output changed
    Failed test-share-safe.t: output changed

Most of the issues seem related to loading help for disabled extensions from
`hgext.__index__`, namely the full extension help being unavailable, not being
able to resolve what commands are provided by what extension, and not having the
command level help available.

test-log.t, test-commit-interactive.t, and test-i18n.t look like i18n (or lack
thereof) issues.

test-basic.t is just odd:
    @@ -55,7 +55,7 @@
     On Python 3, stdio may be None:

       $ hg debuguiprompt --config ui.interactive=true 0<&-
    -   abort: Bad file descriptor (no-rhg !)
    +   abort: response expected
        abort: response expected (rhg !)
       [255]
       $ hg version -q 0<&-

// This Source Code Form is subject to the terms of the Mozilla Public
// License, v. 2.0. If a copy of the MPL was not distributed with this
// file, You can obtain one at https://mozilla.org/MPL/2.0/.

/*! Build script to integrate PyOxidizer. */

fn main() {
    if let Ok(config_rs) =
        std::env::var("DEP_PYTHONXY_DEFAULT_PYTHON_CONFIG_RS")
    {
        println!(
            "cargo:rustc-env=PYOXIDIZER_DEFAULT_PYTHON_CONFIG_RS={}",
            config_rs
        );
    } else {
        panic!("unable to find build artifacts generated by pyembed crate");
    }
}