##// END OF EJS Templates
debugcommands: move away from line buffered output on binary stream...
debugcommands: move away from line buffered output on binary stream Line buffering on binary file objects is apparently undefined behavior in Python and emits a RuntimeWarning on Python 3.8. See https://bugs.python.org/issue32236. This commit changes the I/O logging file descriptor from line buffered to unbuffered to work around this. I'm no fan of unbuffered I/O for performance reasons. But I don't think it is an issue here given the nature of the code. With this change, test-ssh-proto.t now passes on Python 3.8. Differential Revision: https://phab.mercurial-scm.org/D7948
Gregory Szorc -
r44582:52f8b07a default
Show More
Name Size Modified Last Commit Author
/ rust / hgcli
src
Cargo.lock Loading ...
Cargo.toml Loading ...
README.rst Loading ...
build.rs Loading ...

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.