This is an archive of the discontinued Mercurial Phabricator instance.

Differential D7655

rust-index: add a struct wrapping the C index
ClosedPublic

Authored by marmoute on Dec 13 2019, 3:11 PM.

Details

Reviewers
Alphare
indygreg
Group Reviewers
hg-reviewers
Commits
rHGb69d5f3a41d0: rust-index: add a struct wrapping the C index
Summary

Implementing the full index logic in one go is journey larger than we would
like.

To achieve a smoother transition, we start with a simple Rust wrapper that delegates
allwork to the current C implementation. Once we will have a fully working index
object in Rust, we can easily start using more and more Rust Code with it.

The object in this patch is functional and tested. However, multiple of the
currently existing rust (in the hg-cpython crate) requires a Graph. Right
now we build this Graph (as cindex::Index) using the C index passed as
a PyObject. They will have to be updated to be made compatible.

Diff Detail

Repository
rHG Mercurial
Lint
Automatic diff as part of commit; lint not applicable.
Unit
Automatic diff as part of commit; unit tests not applicable.

Event Timeline

marmoute created this revision.Dec 13 2019, 3:11 PM
marmoute updated this revision to Diff 18888.Dec 19 2019, 1:09 PM
Alphare accepted this revision.Dec 20 2019, 3:38 AM
indygreg accepted this revision.Dec 23 2019, 1:01 PM
indygreg added a subscriber: indygreg.
indygreg added inline comments.
tests/test-rust-revlog.py
18

ancestor should probably be revlog here. I can fix in flight.

This revision is now accepted and ready to land.Dec 23 2019, 1:01 PM
gracinet added a commit: rHGb69d5f3a41d0: rust-index: add a struct wrapping the C index.Dec 23 2019, 1:07 PM
Closed by commit rHGb69d5f3a41d0: rust-index: add a struct wrapping the C index (authored by gracinet). · Explain Why
This revision was automatically updated to reflect the committed changes.

Revision Contents
Changeset List

Diff 18920

rust/hg-cpython/src/lib.rs

"Mercurial core concepts - Rust implementation", "Mercurial core concepts - Rust implementation",
)?; )?;
let dotted_name: String = m.get(py, "__name__")?.extract(py)?; let dotted_name: String = m.get(py, "__name__")?.extract(py)?;
m.add(py, "ancestor", ancestors::init_module(py, &dotted_name)?)?; m.add(py, "ancestor", ancestors::init_module(py, &dotted_name)?)?;
m.add(py, "dagop", dagops::init_module(py, &dotted_name)?)?; m.add(py, "dagop", dagops::init_module(py, &dotted_name)?)?;
m.add(py, "discovery", discovery::init_module(py, &dotted_name)?)?; m.add(py, "discovery", discovery::init_module(py, &dotted_name)?)?;
m.add(py, "dirstate", dirstate::init_module(py, &dotted_name)?)?; m.add(py, "dirstate", dirstate::init_module(py, &dotted_name)?)?;
m.add(py, "revlog", revlog::init_module(py, &dotted_name)?)?;
m.add( m.add(
py, py,
"filepatterns", "filepatterns",
filepatterns::init_module(py, &dotted_name)?, filepatterns::init_module(py, &dotted_name)?,
)?; )?;
m.add( m.add(
py, py,
"parsers", "parsers",

rust/hg-cpython/src/revlog.rs

// revlog.rs // revlog.rs
// //
// Copyright 2019 Georges Racinet <georges.racinet@octobus.net> // Copyright 2019 Georges Racinet <georges.racinet@octobus.net>
// //
// This software may be used and distributed according to the terms of the // This software may be used and distributed according to the terms of the
// GNU General Public License version 2 or any later version. // GNU General Public License version 2 or any later version.
use crate::cindex; use crate::cindex;
use cpython::{PyObject, PyResult, Python}; use cpython::{
ObjectProtocol, PyDict, PyModule, PyObject, PyResult, PyTuple, Python,
PythonObject, ToPyObject,
};
use hg::Revision;
use std::cell::RefCell;
/// Return a Struct implementing the Graph trait /// Return a Struct implementing the Graph trait
pub(crate) fn pyindex_to_graph( pub(crate) fn pyindex_to_graph(
py: Python, py: Python,
index: PyObject, index: PyObject,
) -> PyResult<cindex::Index> { ) -> PyResult<cindex::Index> {
cindex::Index::new(py, index) cindex::Index::new(py, index)
} }
py_class!(pub class MixedIndex |py| {
data cindex: RefCell<cindex::Index>;
def __new__(_cls, cindex: PyObject) -> PyResult<MixedIndex> {
Self::create_instance(py, RefCell::new(
cindex::Index::new(py, cindex)?))
}
// Reforwarded C index API
// index_methods (tp_methods). Same ordering as in revlog.c
/// return the gca set of the given revs
def ancestors(&self, *args, **kw) -> PyResult<PyObject> {
self.call_cindex(py, "ancestors", args, kw)
}
/// return the heads of the common ancestors of the given revs
def commonancestorsheads(&self, *args, **kw) -> PyResult<PyObject> {
self.call_cindex(py, "commonancestorsheads", args, kw)
}
/// clear the index caches
def clearcaches(&self, *args, **kw) -> PyResult<PyObject> {
self.call_cindex(py, "clearcaches", args, kw)
}
/// get an index entry
def get(&self, *args, **kw) -> PyResult<PyObject> {
self.call_cindex(py, "get", args, kw)
}
/// return `rev` associated with a node or None
def get_rev(&self, *args, **kw) -> PyResult<PyObject> {
self.call_cindex(py, "get_rev", args, kw)
}
/// return True if the node exist in the index
def has_node(&self, *args, **kw) -> PyResult<PyObject> {
self.call_cindex(py, "has_node", args, kw)
}
/// return `rev` associated with a node or raise RevlogError
def rev(&self, *args, **kw) -> PyResult<PyObject> {
self.call_cindex(py, "rev", args, kw)
}
/// compute phases
def computephasesmapsets(&self, *args, **kw) -> PyResult<PyObject> {
self.call_cindex(py, "computephasesmapsets", args, kw)
}
/// reachableroots
def reachableroots2(&self, *args, **kw) -> PyResult<PyObject> {
self.call_cindex(py, "reachableroots2", args, kw)
}
/// get head revisions
def headrevs(&self, *args, **kw) -> PyResult<PyObject> {
self.call_cindex(py, "headrevs", args, kw)
}
/// get filtered head revisions
def headrevsfiltered(&self, *args, **kw) -> PyResult<PyObject> {
self.call_cindex(py, "headrevsfiltered", args, kw)
}
/// True if the object is a snapshot
def issnapshot(&self, *args, **kw) -> PyResult<PyObject> {
self.call_cindex(py, "issnapshot", args, kw)
}
/// Gather snapshot data in a cache dict
def findsnapshots(&self, *args, **kw) -> PyResult<PyObject> {
self.call_cindex(py, "findsnapshots", args, kw)
}
/// determine revisions with deltas to reconstruct fulltext
def deltachain(&self, *args, **kw) -> PyResult<PyObject> {
self.call_cindex(py, "deltachain", args, kw)
}
/// slice planned chunk read to reach a density threshold
def slicechunktodensity(&self, *args, **kw) -> PyResult<PyObject> {
self.call_cindex(py, "slicechunktodensity", args, kw)
}
/// append an index entry
def append(&self, *args, **kw) -> PyResult<PyObject> {
self.call_cindex(py, "append", args, kw)
}
/// match a potentially ambiguous node ID
def partialmatch(&self, *args, **kw) -> PyResult<PyObject> {
self.call_cindex(py, "partialmatch", args, kw)
}
/// find length of shortest hex nodeid of a binary ID
def shortest(&self, *args, **kw) -> PyResult<PyObject> {
self.call_cindex(py, "shortest", args, kw)
}
/// stats for the index
def stats(&self, *args, **kw) -> PyResult<PyObject> {
self.call_cindex(py, "stats", args, kw)
}
// index_sequence_methods and index_mapping_methods.
//
// Since we call back through the high level Python API,
// there's no point making a distinction between index_get
// and index_getitem.
def __len__(&self) -> PyResult<usize> {
self.cindex(py).borrow().inner().len(py)
}
def __getitem__(&self, key: PyObject) -> PyResult<PyObject> {
// this conversion seems needless, but that's actually because
// `index_getitem` does not handle conversion from PyLong,
// which expressions such as [e for e in index] internally use.
// Note that we don't seem to have a direct way to call
// PySequence_GetItem (does the job), which would be better for
// for performance
let key = match key.extract::<Revision>(py) {
Ok(rev) => rev.to_py_object(py).into_object(),
Err(_) => key,
};
self.cindex(py).borrow().inner().get_item(py, key)
}
def __setitem__(&self, key: PyObject, value: PyObject) -> PyResult<()> {
self.cindex(py).borrow().inner().set_item(py, key, value)
}
def __delitem__(&self, key: PyObject) -> PyResult<()> {
self.cindex(py).borrow().inner().del_item(py, key)
}
def __contains__(&self, item: PyObject) -> PyResult<bool> {
// ObjectProtocol does not seem to provide contains(), so
// this is an equivalent implementation of the index_contains()
// defined in revlog.c
let cindex = self.cindex(py).borrow();
match item.extract::<Revision>(py) {
Ok(rev) => {
Ok(rev >= -1 && rev < cindex.inner().len(py)? as Revision)
}
Err(_) => {
cindex.inner().call_method(
py,
"has_node",
PyTuple::new(py, &[item]),
None)?
.extract(py)
}
}
}
});
impl MixedIndex {
/// forward a method call to the underlying C index
fn call_cindex(
&self,
py: Python,
name: &str,
args: &PyTuple,
kwargs: Option<&PyDict>,
) -> PyResult<PyObject> {
self.cindex(py)
.borrow()
.inner()
.call_method(py, name, args, kwargs)
}
}
/// Create the module, with __package__ given from parent
pub fn init_module(py: Python, package: &str) -> PyResult<PyModule> {
let dotted_name = &format!("{}.revlog", package);
let m = PyModule::new(py, dotted_name)?;
m.add(py, "__package__", package)?;
m.add(py, "__doc__", "RevLog - Rust implementations")?;
m.add_class::<MixedIndex>(py)?;
let sys = PyModule::import(py, "sys")?;
let sys_modules: PyDict = sys.get(py, "modules")?.extract(py)?;
sys_modules.set_item(py, dotted_name, &m)?;
Ok(m)
}

tests/test-rust-revlog.py

  • This file was added.
from __future__ import absolute_import
import unittest
try:
from mercurial import rustext
rustext.__name__ # trigger immediate actual import
except ImportError:
rustext = None
else:
from mercurial.rustext import revlog
from mercurial.testing import revlog as revlogtesting
@unittest.skipIf(
rustext is None, "rustext module revlog relies on is not available",
)
indygregUnsubmitted
Not Done

ancestor should probably be revlog here. I can fix in flight.

indygreg: `ancestor` should probably be `revlog` here. I can fix in flight.
class RustRevlogIndexTest(revlogtesting.RevlogBasedTestBase):
def test_heads(self):
idx = self.parseindex()
rustidx = revlog.MixedIndex(idx)
self.assertEqual(rustidx.headrevs(), idx.headrevs())
def test_len(self):
idx = self.parseindex()
rustidx = revlog.MixedIndex(idx)
self.assertEqual(len(rustidx), len(idx))
if __name__ == '__main__':
import silenttestrunner
silenttestrunner.main(__name__)