##// END OF EJS Templates
revlog: using two new functions in C capsule from Rust code...
revlog: using two new functions in C capsule from Rust code We expose `index_length` and `index_node` in the C capsule, so that the Rust representation of the C index can implement the `RevlogIndex` trait. Because our `Node` is actually a one-field struct, we have to decorate it for direct FFI exchange with the C `char*` It would be a good thing to get a length from the C layer, but doing so right now would probably interfere with the upcoming changes that will happen there for the hash length. Differential Revision: https://phab.mercurial-scm.org/D8152

File last commit:

r44573:8a3b045d default
r44989:16634951 default
Show More
README.rst
58 lines | 1.8 KiB | text/x-rst | RstLexer

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.