Mercurial > hg
view rust/hgcli/README.md @ 50400:95acba2c29f6
encoding: avoid quadratic time complexity when json-encoding non-UTF8 strings
Apparently the code uses "+=" with a bytes object, which is linear-time, so the
whole encoding is quadratic-time. This patch makes us use a bytearray object,
instead, which has a(n amortized-)constant-time append operation.
The encoding is still not particularly fast, but at least a 10MB file
takes tens of seconds, not many hours to encode.
author | Arseniy Alekseyev <aalekseyev@janestreet.com> |
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date | Mon, 06 Mar 2023 11:27:57 +0000 |
parents | 16c3fe46929a |
children | 45ba8416afc4 |
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# 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) 2005-2020 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