rust-cpython: binding for AncestorsIterator
It's now reachable from Python as
rustext.ancestor.AncestorsIterator
Tests are provided in the previously introduced
Python testcase: this is much more convenient
that writing lengthy Rust code to call into Python.
Differential Revision: https://phab.mercurial-scm.org/D5439
--- a/rust/hg-cpython/src/ancestors.rs Mon Dec 03 07:44:08 2018 +0100
+++ b/rust/hg-cpython/src/ancestors.rs Thu Dec 06 20:01:21 2018 +0100
@@ -7,7 +7,68 @@
//! Bindings for the hg::ancestors module provided by the
//! `hg-core` crate. From Python, this will be seen as `rustext.ancestor`
-use cpython::{PyDict, PyModule, PyResult, Python};
+use cindex::Index;
+use cpython::{
+ ObjectProtocol, PyClone, PyDict, PyModule, PyObject, PyResult, Python,
+};
+use exceptions::GraphError;
+use hg;
+use hg::AncestorsIterator as CoreIterator;
+use hg::Revision;
+use std::cell::RefCell;
+
+/// Utility function to convert a Python iterable into a Vec<Revision>
+///
+/// We need this to feed to AncestorIterators constructors because
+/// a PyErr can arise at each step of iteration, whereas our inner objects
+/// expect iterables over Revision, not over some Result<Revision, PyErr>
+fn reviter_to_revvec(py: Python, revs: PyObject) -> PyResult<Vec<Revision>> {
+ revs.iter(py)?
+ .map(|r| r.and_then(|o| o.extract::<Revision>(py)))
+ .collect()
+}
+
+py_class!(class AncestorsIterator |py| {
+ // TODO RW lock ?
+ data inner: RefCell<Box<CoreIterator<Index>>>;
+
+ def __next__(&self) -> PyResult<Option<Revision>> {
+ match self.inner(py).borrow_mut().next() {
+ Some(Err(e)) => Err(GraphError::pynew(py, e)),
+ None => Ok(None),
+ Some(Ok(r)) => Ok(Some(r)),
+ }
+ }
+
+ def __contains__(&self, rev: Revision) -> PyResult<bool> {
+ self.inner(py).borrow_mut().contains(rev).map_err(|e| GraphError::pynew(py, e))
+ }
+
+ def __iter__(&self) -> PyResult<Self> {
+ Ok(self.clone_ref(py))
+ }
+
+ def __new__(_cls, index: PyObject, initrevs: PyObject, stoprev: Revision,
+ inclusive: bool) -> PyResult<AncestorsIterator> {
+ let initvec = reviter_to_revvec(py, initrevs)?;
+ let ait = match hg::AncestorsIterator::new(Index::new(py, index)?,
+ initvec, stoprev,
+ inclusive) {
+ Ok(ait) => ait,
+ Err(e) => {
+ return Err(GraphError::pynew(py, e));
+ }
+ };
+ AncestorsIterator::from_inner(py, ait)
+ }
+
+});
+
+impl AncestorsIterator {
+ pub fn from_inner(py: Python, ait: CoreIterator<Index>) -> PyResult<Self> {
+ Self::create_instance(py, RefCell::new(Box::new(ait)))
+ }
+}
/// Create the module, with __package__ given from parent
pub fn init_module(py: Python, package: &str) -> PyResult<PyModule> {
@@ -19,6 +80,7 @@
"__doc__",
"Generic DAG ancestor algorithms - Rust implementation",
)?;
+ m.add_class::<AncestorsIterator>(py)?;
let sys = PyModule::import(py, "sys")?;
let sys_modules: PyDict = sys.get(py, "modules")?.extract(py)?;
--- a/tests/test-rust-ancestor.py Mon Dec 03 07:44:08 2018 +0100
+++ b/tests/test-rust-ancestor.py Thu Dec 06 20:01:21 2018 +0100
@@ -1,19 +1,46 @@
from __future__ import absolute_import
+import sys
import unittest
try:
from mercurial import rustext
+ rustext.__name__ # trigger immediate actual import
except ImportError:
rustext = None
+else:
+ # this would fail already without appropriate ancestor.__package__
+ from mercurial.rustext.ancestor import AncestorsIterator
try:
from mercurial.cext import parsers as cparsers
except ImportError:
cparsers = None
+# picked from test-parse-index2, copied rather than imported
+# so that it stays stable even if test-parse-index2 changes or disappears.
+data_non_inlined = (
+ b'\x00\x00\x00\x01\x00\x00\x00\x00\x00\x01D\x19'
+ b'\x00\x07e\x12\x00\x00\x00\x00\x00\x00\x00\x00\xff\xff\xff\xff'
+ b'\xff\xff\xff\xff\xd1\xf4\xbb\xb0\xbe\xfc\x13\xbd\x8c\xd3\x9d'
+ b'\x0f\xcd\xd9;\x8c\x07\x8cJ/\x00\x00\x00\x00\x00\x00\x00\x00\x00'
+ b'\x00\x00\x00\x00\x00\x00\x01D\x19\x00\x00\x00\x00\x00\xdf\x00'
+ b'\x00\x01q\x00\x00\x00\x01\x00\x00\x00\x01\x00\x00\x00\x00\xff'
+ b'\xff\xff\xff\xc1\x12\xb9\x04\x96\xa4Z1t\x91\xdfsJ\x90\xf0\x9bh'
+ b'\x07l&\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00'
+ b'\x00\x01D\xf8\x00\x00\x00\x00\x01\x1b\x00\x00\x01\xb8\x00\x00'
+ b'\x00\x01\x00\x00\x00\x02\x00\x00\x00\x01\xff\xff\xff\xff\x02\n'
+ b'\x0e\xc6&\xa1\x92\xae6\x0b\x02i\xfe-\xe5\xbao\x05\xd1\xe7\x00'
+ b'\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x01F'
+ b'\x13\x00\x00\x00\x00\x01\xec\x00\x00\x03\x06\x00\x00\x00\x01'
+ b'\x00\x00\x00\x03\x00\x00\x00\x02\xff\xff\xff\xff\x12\xcb\xeby1'
+ b'\xb6\r\x98B\xcb\x07\xbd`\x8f\x92\xd9\xc4\x84\xbdK\x00\x00\x00'
+ b'\x00\x00\x00\x00\x00\x00\x00\x00\x00'
+ )
+
+
@unittest.skipIf(rustext is None or cparsers is None,
- "rustext.ancestor or the C Extension parsers module "
- "it relies on is not available")
+ "rustext or the C Extension parsers module "
+ "ancestor relies on is not available")
class rustancestorstest(unittest.TestCase):
"""Test the correctness of binding to Rust code.
@@ -27,11 +54,52 @@
Algorithmic correctness is asserted by the Rust unit tests.
"""
- def testmodule(self):
- self.assertTrue('DAG' in rustext.ancestor.__doc__)
+ def parseindex(self):
+ return cparsers.parse_index2(data_non_inlined, False)[0]
+
+ def testiteratorrevlist(self):
+ idx = self.parseindex()
+ # checking test assumption about the index binary data:
+ self.assertEqual({i: (r[5], r[6]) for i, r in enumerate(idx)},
+ {0: (-1, -1),
+ 1: (0, -1),
+ 2: (1, -1),
+ 3: (2, -1)})
+ ait = AncestorsIterator(idx, [3], 0, True)
+ self.assertEqual([r for r in ait], [3, 2, 1, 0])
+
+ ait = AncestorsIterator(idx, [3], 0, False)
+ self.assertEqual([r for r in ait], [2, 1, 0])
+
+ def testrefcount(self):
+ idx = self.parseindex()
+ start_count = sys.getrefcount(idx)
+
+ # refcount increases upon iterator init...
+ ait = AncestorsIterator(idx, [3], 0, True)
+ self.assertEqual(sys.getrefcount(idx), start_count + 1)
+ self.assertEqual(next(ait), 3)
+
+ # and decreases once the iterator is removed
+ del ait
+ self.assertEqual(sys.getrefcount(idx), start_count)
+
+ # and removing ref to the index after iterator init is no issue
+ ait = AncestorsIterator(idx, [3], 0, True)
+ del idx
+ self.assertEqual([r for r in ait], [3, 2, 1, 0])
def testgrapherror(self):
- self.assertTrue('GraphError' in dir(rustext))
+ data = (data_non_inlined[:64 + 27] +
+ b'\xf2' +
+ data_non_inlined[64 + 28:])
+ idx = cparsers.parse_index2(data, False)[0]
+ with self.assertRaises(rustext.GraphError) as arc:
+ AncestorsIterator(idx, [1], -1, False)
+ exc = arc.exception
+ self.assertIsInstance(exc, ValueError)
+ # rust-cpython issues appropriate str instances for Python 2 and 3
+ self.assertEqual(exc.args, ('ParentOutOfRange', 1))
if __name__ == '__main__':