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

chg: populate CHGHG if not set...

chg: populate CHGHG if not set Normally, chg determines which `hg` executable to use by first consulting the `$CHGHG` and `$HG` environment variables, and if neither are present defaults to the `hg` found in the user's `$PATH`. If built with the `HGPATHREL` compiler flag, chg will instead assume that there exists an `hg` executable in the same directory as the `chg` binary and attempt to use that. This can cause problems in situations where there are multiple actively-used Mercurial installations on the same system. When a `chg` client connects to a running command server, the server process performs some basic validation to determine whether a new command server needs to be spawned. These checks include things like checking certain "sensitive" environment variables and config sections, as well as checking whether the mtime of the extensions, hg's `__version__.py` module, and the Python interpreter have changed. Crucially, the command server doesn't explicitly check whether the executable it is running from matches the executable that the `chg` client would have otherwise invoked had there been no existing command server process. Without `HGPATHREL`, this still gets implicitly checked during the validation step, because the only way to specify an alternate hg executable (apart from `$PATH`) is via the `$CHGHG` and `$HG` environment variables, both of which are checked. With `HGPATHREL`, however, the command server has no way of knowing which hg executable the client would have run. This means that a client located at `/version_B/bin/chg` will happily connect to a command server running `/version_A/bin/hg` instead of `/version_B/bin/hg` as expected. A simple solution is to have the client set `$CHGHG` itself, which then allows the command server's environment validation to work as intended. I have tested this manually using two locally built hg installations and it seems to work with no ill effects. That said, I'm not sure how to write an automated test for this since the `chg` available to the tests isn't even built with the `HGPATHREL` compiler flag to begin with.

Kyle Lippincott - - Load All Authors

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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

        Kyle Lippincott
    
pyoxidizer: update README.md with several small fixes...

              r49087
            
      First, acquire and build a copy of PyOxidizer; you probably want to do this in

      some directory outside of your clone of Mercurial:

        Gregory Szorc
    
hgcli: customize for Mercurial...

              r45129
            
          $ git clone https://github.com/indygreg/PyOxidizer.git

          $ cd PyOxidizer

          $ cargo build --release

        Kyle Lippincott
    
pyoxidizer: update README.md with several small fixes...

              r49087
            
      Then build this Rust project using the built `pyoxidizer` executable:

        Gregory Szorc
    
hgcli: customize for Mercurial...

              r45129
            
        Kyle Lippincott
    
pyoxidizer: update README.md with several small fixes...

              r49087
            
          $ /path/to/pyoxidizer/target/release/pyoxidizer build --release

        Gregory Szorc
    
hgcli: customize for Mercurial...

              r45129
            
      If all goes according to plan, there should be an assembled application

        Kyle Lippincott
    
pyoxidizer: update README.md with several small fixes...

              r49087
            
      under `build/<arch>/release/app/` with an `hg` executable:

        Gregory Szorc
    
hgcli: customize for Mercurial...

              r45129
            
        Kyle Lippincott
    
pyoxidizer: update README.md with several small fixes...

              r49087
            
          $ build/x86_64-unknown-linux-gnu/release/app/hg version

        Gregory Szorc
    
hgcli: customize for Mercurial...

              r45129
            
          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

        Kyle Lippincott
    
pyoxidizer: update README.md with several small fixes...

              r49087
            
          $ PYTHONPATH=`pwd`/.. python3.9 run-tests.py \

              --with-hg `pwd`/../rust/hgcli/build/x86_64-unknown-linux-gnu/release/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
g F	Goto files page with file search activated
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

Kyle Lippincott pyoxidizer: update README.md with several small fixes...	r49087	First, acquire and build a copy of PyOxidizer; you probably want to do this in
		some directory outside of your clone of Mercurial:
Gregory Szorc hgcli: customize for Mercurial...	r45129
		$ git clone https://github.com/indygreg/PyOxidizer.git
		$ cd PyOxidizer
		$ cargo build --release

Kyle Lippincott pyoxidizer: update README.md with several small fixes...	r49087	Then build this Rust project using the built `pyoxidizer` executable:
Gregory Szorc hgcli: customize for Mercurial...	r45129
Kyle Lippincott pyoxidizer: update README.md with several small fixes...	r49087	$ /path/to/pyoxidizer/target/release/pyoxidizer build --release
Gregory Szorc hgcli: customize for Mercurial...	r45129
		If all goes according to plan, there should be an assembled application
Kyle Lippincott pyoxidizer: update README.md with several small fixes...	r49087	under `build/<arch>/release/app/` with an `hg` executable:
Gregory Szorc hgcli: customize for Mercurial...	r45129
Kyle Lippincott pyoxidizer: update README.md with several small fixes...	r49087	$ build/x86_64-unknown-linux-gnu/release/app/hg version
Gregory Szorc hgcli: customize for Mercurial...	r45129	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
Kyle Lippincott pyoxidizer: update README.md with several small fixes...	r49087	$ PYTHONPATH=`pwd`/.. python3.9 run-tests.py \
		--with-hg `pwd`/../rust/hgcli/build/x86_64-unknown-linux-gnu/release/app/hg