upstream/mercurial-mirror Files · rust/hgcli/README.md

dirstate-tree: Avoid BTreeMap double-lookup when inserting a dirstate entry...

dirstate-tree: Avoid BTreeMap double-lookup when inserting a dirstate entry The child nodes of a given node in the tree-shaped dirstate are kept in a `BTreeMap` where keys are file names as strings. Finding or inserting a value in the map takes `O(log(n))` string comparisons, which adds up when constructing the tree. The `entry` API allows finding a "spot" in the map that may or may not be occupied and then access that value or insert a new one without doing map lookup again. However the current API is limited in that calling `entry` requires an owned key (and so a memory allocation), even if it ends up not being used in the case where the map already has a value with an equal key. This is still a win, with 4% better end-to-end time for `hg status` measured here with hyperfine: ``` Benchmark : ../hg2/hg status -R $REPO --config=experimental.dirstate-tree.in-memory=1 Time (mean ± σ): 1.337 s ± 0.018 s [User: 892.9 ms, System: 437.5 ms] Range (min … max): 1.316 s … 1.373 s 10 runs Benchmark : ./hg status -R $REPO --config=experimental.dirstate-tree.in-memory=1 Time (mean ± σ): 1.291 s ± 0.008 s [User: 853.4 ms, System: 431.1 ms] Range (min … max): 1.283 s … 1.309 s 10 runs Summary './hg status -R $REPO --config=experimental.dirstate-tree.in-memory=1' ran 1.04 ± 0.02 times faster than '../hg2/hg status -R $REPO --config=experimental.dirstate-tree.in-memory=1' ``` * ./hg is this revision * ../hg2/hg is its parent * $REPO is an old snapshot of mozilla-central Differential Revision: https://phab.mercurial-scm.org/D10550

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        Gregory Szorc
    
hgcli: customize for Mercurial...

              r45129
            
      # 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

      This project currently requires an unreleased version of PyOxidizer

      (0.7.0-pre). For best results, build the exact PyOxidizer commit

      as defined in the `pyoxidizer.bzl` file:

          $ git clone https://github.com/indygreg/PyOxidizer.git

          $ cd PyOxidizer

          $ git checkout <Git commit from pyoxidizer.bzl>

          $ cargo build --release

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

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

      If all goes according to plan, there should be an assembled application

      under `build/<arch>/debug/app/` with an `hg` executable:

          $ build/x86_64-unknown-linux-gnu/debug/app/hg version

          Mercurial Distributed SCM (version 5.3.1+433-f99cd77d53dc+20200331)

          (see https://mercurial-scm.org for more information)

        Raphaël Gomès
    
contributor: change mentions of mpm to olivia...

              r47575
            
          Copyright (C) 2005-2020 Olivia Mackall and others

        Gregory Szorc
    
hgcli: customize for Mercurial...

              r45129
            
          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`/.. python3.7 run-tests.py \

              --with-hg `pwd`/../rust/hgcli/build/x86_64-unknown-linux-gnu/debug/app/hg

	Site-wide shortcuts
/	Use quick search box
g h	Goto home page
g g	Goto my private gists page
g G	Goto my public gists page
g 0-9	Goto bookmarked items from 0-9
n r	New repository page
n g	New gist page

	Repositories
g s	Goto summary page
g c	Goto changelog page
g f	Goto files page
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g p	Goto pull requests page
g o	Goto repository settings
g O	Goto repository access permissions settings
t s	Toggle sidebar on some pages

Gregory Szorc hgcli: customize for Mercurial...	r45129	# 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

		This project currently requires an unreleased version of PyOxidizer
		(0.7.0-pre). For best results, build the exact PyOxidizer commit
		as defined in the `pyoxidizer.bzl` file:

		$ git clone https://github.com/indygreg/PyOxidizer.git
		$ cd PyOxidizer
		$ git checkout <Git commit from pyoxidizer.bzl>
		$ cargo build --release

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

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

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

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

Raphaël Gomès contributor: change mentions of mpm to olivia...	r47575	Copyright (C) 2005-2020 Olivia Mackall and others
Gregory Szorc hgcli: customize for Mercurial...	r45129	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`/.. python3.7 run-tests.py \
		--with-hg `pwd`/../rust/hgcli/build/x86_64-unknown-linux-gnu/debug/app/hg