view rust/hgcli/README.md @ 52095:3e7b9357bbb8

tests: add coverage to for `HGCB_BUNDLE_BASENAME` with special characters

Per request on IRC, to show the behavior of dropping the quoting of
`HGCB_BUNDLE_BASENAME` in the next commit.  This current failure is basically
the same error and output that currently happens on Windows with any path (even
without the embedded quote).  The only difference is Windows doesn't print the
`cp: cannot stat ...` line.

# Oxidized Mercurial

This project provides a Rust implementation of the Mercurial (`hg`)
version control tool.

Under the hood, the project uses
[PyOxidizer](https://github.com/indygreg/PyOxidizer) to embed a Python
interpreter in a binary built with Rust. At run-time, the Rust `fn main()`
is called and Rust code handles initial process startup. An in-process
Python interpreter is started (if needed) to provide additional
functionality.

# Building

First, acquire and build a copy of PyOxidizer; you probably want to do this in
some directory outside of your clone of Mercurial:

    $ git clone https://github.com/indygreg/PyOxidizer.git
    $ cd PyOxidizer
    $ cargo build --release

Then build this Rust project using the built `pyoxidizer` executable:

    $ /path/to/pyoxidizer/target/release/pyoxidizer build --release

If all goes according to plan, there should be an assembled application
under `build/<arch>/release/app/` with an `hg` executable:

    $ build/x86_64-unknown-linux-gnu/release/app/hg version
    Mercurial Distributed SCM (version 5.3.1+433-f99cd77d53dc+20200331)
    (see https://mercurial-scm.org for more information)

    Copyright (C) 2005-2024 Olivia Mackall and others
    This is free software; see the source for copying conditions. There is NO
    warranty; not even for MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.

# Running Tests

To run tests with a built `hg` executable, you can use the `--with-hg`
argument to `run-tests.py`. But there's a wrinkle: many tests run custom
Python scripts that need to `import` modules provided by Mercurial. Since
these modules are embedded in the produced `hg` executable, a regular
Python interpreter can't access them! To work around this, set `PYTHONPATH`
to the Mercurial source directory. e.g.:

    $ cd /path/to/hg/src/tests
    $ PYTHONPATH=`pwd`/.. python3.9 run-tests.py \
        --with-hg `pwd`/../rust/hgcli/build/x86_64-unknown-linux-gnu/release/app/hg