comparison rust/hg-cpython/src/ancestors.rs @ 50979:4c5f6e95df84

rust: make `Revision` a newtype

This change is the one we've been building towards during this series.
The aim is to make `Revision` mean more than a simple integer, holding
the information that it is valid for a given revlog index.
While this still allows for programmer error, since creating a revision
directly and querying a different index with a "checked" revision are
still possible, the friction created by the newtype will hopefully make
us think twice about which type to use.

Enough of the Rust ecosystem relies on the newtype pattern to be
efficiently optimized away (even compiler in codegen tests¹), so I'm not
worried about this being a fundamental problem.

[1] https://github.com/rust-lang/rust/blob/7a70647f195f6b0a0f1ebd72b1542ba91a32f43a/tests/codegen/vec-in-place.rs#L47

50978:27e773aa607d

//!
//! [`LazyAncestors`]: struct.LazyAncestors.html
//! [`MissingAncestors`]: struct.MissingAncestors.html
//! [`AncestorsIterator`]: struct.AncestorsIterator.html
use crate::revlog::pyindex_to_graph;
use crate::{
    cindex::Index, conversion::rev_pyiter_collect, exceptions::GraphError,
};
use cpython::{
    ObjectProtocol, PyClone, PyDict, PyList, PyModule, PyObject, PyResult,

};

py_class!(pub class AncestorsIterator |py| {
    data inner: RefCell<Box<VCGAncestorsIterator<Index>>>;

    def __next__(&self) -> PyResult<Option<Revision>> {
        match self.inner(py).borrow_mut().next() {
            Some(Err(e)) => Err(GraphError::pynew_from_vcsgraph(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_from_vcsgraph(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: Vec<Revision> = rev_pyiter_collect(py, &initrevs)?;
        let ait = VCGAncestorsIterator::new(
            pyindex_to_graph(py, index)?,
            initvec,
            stoprev,
            inclusive,
        )
        .map_err(|e| GraphError::pynew_from_vcsgraph(py, e))?;
        AncestorsIterator::from_inner(py, ait)
    }

}

py_class!(pub class LazyAncestors |py| {
    data inner: RefCell<Box<VCGLazyAncestors<Index>>>;

    def __contains__(&self, rev: Revision) -> PyResult<bool> {
        self.inner(py)
            .borrow_mut()
            .contains(rev)
            .map_err(|e| GraphError::pynew_from_vcsgraph(py, e))
    }

    def __iter__(&self) -> PyResult<AncestorsIterator> {
        AncestorsIterator::from_inner(py, self.inner(py).borrow().iter())

    def __bool__(&self) -> PyResult<bool> {
        Ok(!self.inner(py).borrow().is_empty())
    }

    def __new__(_cls, index: PyObject, initrevs: PyObject, stoprev: Revision,
                inclusive: bool) -> PyResult<Self> {
        let initvec: Vec<Revision> = rev_pyiter_collect(py, &initrevs)?;

        let lazy =
            VCGLazyAncestors::new(pyindex_to_graph(py, index)?,
                          initvec, stoprev, inclusive)
                .map_err(|e| GraphError::pynew_from_vcsgraph(py, e))?;

        Self::create_instance(py, RefCell::new(Box::new(lazy)))
        }

});

py_class!(pub class MissingAncestors |py| {
    data inner: RefCell<Box<CoreMissing<Index>>>;

    def __new__(
        _cls,
        index: PyObject,
        bases: PyObject
    )
    -> PyResult<MissingAncestors> {
        let bases_vec: Vec<Revision> = rev_pyiter_collect(py, &bases)?;
        let inner = CoreMissing::new(pyindex_to_graph(py, index)?, bases_vec);
        MissingAncestors::create_instance(py, RefCell::new(Box::new(inner)))
    }

    def hasbases(&self) -> PyResult<bool> {
        Ok(self.inner(py).borrow().has_bases())
    }

    def addbases(&self, bases: PyObject) -> PyResult<PyObject> {
        let mut inner = self.inner(py).borrow_mut();
        let bases_vec: Vec<Revision> = rev_pyiter_collect(py, &bases)?;
        inner.add_bases(bases_vec);
        // cpython doc has examples with PyResult<()> but this gives me
        //   the trait `cpython::ToPyObject` is not implemented for `()`
        // so let's return an explicit None
        Ok(py.None())
    }

    def bases(&self) -> PyResult<HashSet<Revision>> {
        Ok(self.inner(py).borrow().get_bases().clone())
    }

    def basesheads(&self) -> PyResult<HashSet<Revision>> {
        let inner = self.inner(py).borrow();
        inner.bases_heads().map_err(|e| GraphError::pynew(py, e))
    }

    def removeancestorsfrom(&self, revs: PyObject) -> PyResult<PyObject> {
        let mut inner = self.inner(py).borrow_mut();
        // this is very lame: we convert to a Rust set, update it in place
        // and then convert back to Python, only to have Python remove the
        // excess (thankfully, Python is happy with a list or even an iterator)
        // Leads to improve this:
        //  - have the CoreMissing instead do something emit revisions to
        //    discard
        //  - define a trait for sets of revisions in the core and implement
        //    it for a Python set rewrapped with the GIL marker
        let mut revs_pyset: HashSet<Revision> = rev_pyiter_collect(py, &revs)?;
        inner.remove_ancestors_from(&mut revs_pyset)
            .map_err(|e| GraphError::pynew(py, e))?;

        // convert as Python list
        let mut remaining_pyint_vec: Vec<PyObject> = Vec::with_capacity(
            revs_pyset.len());
        for rev in revs_pyset {
            remaining_pyint_vec.push(rev.to_py_object(py).into_object());
        }
        let remaining_pylist = PyList::new(py, remaining_pyint_vec.as_slice());
        revs.call_method(py, "intersection_update", (remaining_pylist, ), None)
    }

    def missingancestors(&self, revs: PyObject) -> PyResult<PyList> {
        let mut inner = self.inner(py).borrow_mut();
        let revs_vec: Vec<Revision> = rev_pyiter_collect(py, &revs)?;
        let missing_vec = match inner.missing_ancestors(revs_vec) {
            Ok(missing) => missing,
            Err(e) => {
                return Err(GraphError::pynew(py, e));
            }
        };
        // convert as Python list
        let mut missing_pyint_vec: Vec<PyObject> = Vec::with_capacity(
            missing_vec.len());
        for rev in missing_vec {
            missing_pyint_vec.push(rev.to_py_object(py).into_object());
        }
        Ok(PyList::new(py, missing_pyint_vec.as_slice()))
    }
});

50979:4c5f6e95df84

//!
//! [`LazyAncestors`]: struct.LazyAncestors.html
//! [`MissingAncestors`]: struct.MissingAncestors.html
//! [`AncestorsIterator`]: struct.AncestorsIterator.html
use crate::revlog::pyindex_to_graph;
use crate::PyRevision;
use crate::{
    cindex::Index, conversion::rev_pyiter_collect, exceptions::GraphError,
};
use cpython::{
    ObjectProtocol, PyClone, PyDict, PyList, PyModule, PyObject, PyResult,

};

py_class!(pub class AncestorsIterator |py| {
    data inner: RefCell<Box<VCGAncestorsIterator<Index>>>;

    def __next__(&self) -> PyResult<Option<PyRevision>> {
        match self.inner(py).borrow_mut().next() {
            Some(Err(e)) => Err(GraphError::pynew_from_vcsgraph(py, e)),
            None => Ok(None),
            Some(Ok(r)) => Ok(Some(PyRevision(r))),
        }
    }

    def __contains__(&self, rev: PyRevision) -> PyResult<bool> {
        self.inner(py).borrow_mut().contains(rev.0)
            .map_err(|e| GraphError::pynew_from_vcsgraph(py, e))
    }

    def __iter__(&self) -> PyResult<Self> {
        Ok(self.clone_ref(py))
    }

    def __new__(
        _cls,
        index: PyObject,
        initrevs: PyObject,
        stoprev: PyRevision,
        inclusive: bool
    ) -> PyResult<AncestorsIterator> {
        let index = pyindex_to_graph(py, index)?;
        let initvec: Vec<_> = rev_pyiter_collect(py, &initrevs, &index)?;
        let ait = VCGAncestorsIterator::new(
            index,
            initvec.into_iter().map(|r| r.0),
            stoprev.0,
            inclusive,
        )
        .map_err(|e| GraphError::pynew_from_vcsgraph(py, e))?;
        AncestorsIterator::from_inner(py, ait)
    }

}

py_class!(pub class LazyAncestors |py| {
    data inner: RefCell<Box<VCGLazyAncestors<Index>>>;

    def __contains__(&self, rev: PyRevision) -> PyResult<bool> {
        self.inner(py)
            .borrow_mut()
            .contains(rev.0)
            .map_err(|e| GraphError::pynew_from_vcsgraph(py, e))
    }

    def __iter__(&self) -> PyResult<AncestorsIterator> {
        AncestorsIterator::from_inner(py, self.inner(py).borrow().iter())

    def __bool__(&self) -> PyResult<bool> {
        Ok(!self.inner(py).borrow().is_empty())
    }

    def __new__(
        _cls,
        index: PyObject,
        initrevs: PyObject,
        stoprev: PyRevision,
        inclusive: bool
    ) -> PyResult<Self> {
        let index = pyindex_to_graph(py, index)?;
        let initvec: Vec<_> = rev_pyiter_collect(py, &initrevs, &index)?;

        let lazy =
            VCGLazyAncestors::new(
                index,
                initvec.into_iter().map(|r| r.0),
                stoprev.0,
                inclusive
            )
            .map_err(|e| GraphError::pynew_from_vcsgraph(py, e))?;

        Self::create_instance(py, RefCell::new(Box::new(lazy)))
        }

});

py_class!(pub class MissingAncestors |py| {
    data inner: RefCell<Box<CoreMissing<Index>>>;
    data index: RefCell<Index>;

    def __new__(
        _cls,
        index: PyObject,
        bases: PyObject
    )
    -> PyResult<MissingAncestors> {
        let index = pyindex_to_graph(py, index)?;
        let bases_vec: Vec<_> = rev_pyiter_collect(py, &bases, &index)?;

        let inner = CoreMissing::new(index.clone_ref(py), bases_vec);
        MissingAncestors::create_instance(
            py,
            RefCell::new(Box::new(inner)),
            RefCell::new(index)
        )
    }

    def hasbases(&self) -> PyResult<bool> {
        Ok(self.inner(py).borrow().has_bases())
    }

    def addbases(&self, bases: PyObject) -> PyResult<PyObject> {
        let index = self.index(py).borrow();
        let bases_vec: Vec<_> = rev_pyiter_collect(py, &bases, &*index)?;
        let mut inner = self.inner(py).borrow_mut();
        inner.add_bases(bases_vec);
        // cpython doc has examples with PyResult<()> but this gives me
        //   the trait `cpython::ToPyObject` is not implemented for `()`
        // so let's return an explicit None
        Ok(py.None())
    }

    def bases(&self) -> PyResult<HashSet<PyRevision>> {
        Ok(
            self.inner(py)
                .borrow()
                .get_bases()
                .iter()
                .map(|r| PyRevision(r.0))
                .collect()
        )
    }

    def basesheads(&self) -> PyResult<HashSet<PyRevision>> {
        let inner = self.inner(py).borrow();
        Ok(
            inner
                .bases_heads()
                .map_err(|e| GraphError::pynew(py, e))?
                .into_iter()
                .map(|r| PyRevision(r.0))
                .collect()
        )
    }

    def removeancestorsfrom(&self, revs: PyObject) -> PyResult<PyObject> {
        let index = self.index(py).borrow();
        // this is very lame: we convert to a Rust set, update it in place
        // and then convert back to Python, only to have Python remove the
        // excess (thankfully, Python is happy with a list or even an iterator)
        // Leads to improve this:
        //  - have the CoreMissing instead do something emit revisions to
        //    discard
        //  - define a trait for sets of revisions in the core and implement
        //    it for a Python set rewrapped with the GIL marker
        let mut revs_pyset: HashSet<Revision> = rev_pyiter_collect(
            py, &revs, &*index
        )?;
        let mut inner = self.inner(py).borrow_mut();
        inner.remove_ancestors_from(&mut revs_pyset)
            .map_err(|e| GraphError::pynew(py, e))?;

        // convert as Python list
        let mut remaining_pyint_vec: Vec<PyObject> = Vec::with_capacity(
            revs_pyset.len());
        for rev in revs_pyset {
            remaining_pyint_vec.push(
                PyRevision(rev.0).to_py_object(py).into_object()
            );
        }
        let remaining_pylist = PyList::new(py, remaining_pyint_vec.as_slice());
        revs.call_method(py, "intersection_update", (remaining_pylist, ), None)
    }

    def missingancestors(&self, revs: PyObject) -> PyResult<PyList> {
        let index = self.index(py).borrow();
        let revs_vec: Vec<Revision> = rev_pyiter_collect(py, &revs, &*index)?;

        let mut inner = self.inner(py).borrow_mut();
        let missing_vec = match inner.missing_ancestors(revs_vec) {
            Ok(missing) => missing,
            Err(e) => {
                return Err(GraphError::pynew(py, e));
            }
        };
        // convert as Python list
        let mut missing_pyint_vec: Vec<PyObject> = Vec::with_capacity(
            missing_vec.len());
        for rev in missing_vec {
            missing_pyint_vec.push(
                PyRevision(rev.0).to_py_object(py).into_object()
            );
        }
        Ok(PyList::new(py, missing_pyint_vec.as_slice()))
    }
});