##// END OF EJS Templates
copies: move short-circuiting of dirstate copies out of _forwardcopies()...
copies: move short-circuiting of dirstate copies out of _forwardcopies() I'd like to move the filtering of copies we do after chaining to the end of all chaining (in a single place in pathcopies()). One problem that came up when trying that was that we allow things like `hg cp -f <file> <existing file>` so the user can later amend that in. Filtering at the end would mean that we remove those copies. That would break `hg st -C`. This patch therefore moves the short-circuiting of dirstate copies into pathcopies() so we can more easily handle the dirstate-only case differently. I initially thought this might change some behavior when the user does `hg status --rev 'wdir()' --rev .` during an uncommitted merge, since _backwardrenames() would reverse the copies in that case. However, I couldn't come up with a test case where it made a difference. Differential Revision: https://phab.mercurial-scm.org/D6600
Martin von Zweigbergk -
r42794:bcb4b5c5 default
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Mercurial Rust Code

This directory contains various Rust code for the Mercurial project.

The top-level Cargo.toml file defines a workspace containing all primary Mercurial crates.

Building

To build the Rust components:

$ cargo build

If you prefer a non-debug / release configuration:

$ cargo build --release

Features

The following Cargo features are available:

localdev (default)

Produce files that work with an in-source-tree build.

In this mode, the build finds and uses a python2.7 binary from PATH. The hg binary assumes it runs from rust/target/<target>hg and it finds Mercurial files at dirname($0)/../../../.

Build Mechanism

The produced hg binary is bound to a CPython installation. The binary links against and loads a CPython library that is discovered at build time (by a build.rs Cargo build script). The Python standard library defined by this CPython installation is also used.

Finding the appropriate CPython installation to use is done by the python27-sys crate's build.rs. Its search order is:

  1. PYTHON_SYS_EXECUTABLE environment variable.
  2. python executable on PATH
  3. python2 executable on PATH
  4. python2.7 executable on PATH

Additional verification of the found Python will be performed by our build.rs to ensure it meets Mercurial's requirements.

Details about the build-time configured Python are built into the produced hg binary. This means that a built hg binary is only suitable for a specific, well-defined role. These roles are controlled by Cargo features (see above).

Running

The hgcli crate produces an hg binary. You can run this binary via cargo run:

$ cargo run --manifest-path hgcli/Cargo.toml

Or directly:

$ target/debug/hg
$ target/release/hg

You can also run the test harness with this binary:

$ ./run-tests.py --with-hg ../rust/target/debug/hg

Note

Integration with the test harness is still preliminary. Remember to cargo build after changes because the test harness doesn't yet automatically build Rust code.