annotate rust/hg-cpython/src/dirstate/dirstate_map.rs @ 44203:2a24ead003f0

rust-cpython: add panicking version of borrow_mut() and use it

The original borrow_mut() is renamed to try_borrow_mut().

Since leak_immutable() no longer incref the borrow count, the caller should
know if the underlying value is borrowed or not. No Python world is involved.
That's why we can simply use the panicking borrow_mut().

// dirstate_map.rs
//
// Copyright 2019 Raphaël Gomès <[e-mail]>
//
// This software may be used and distributed according to the terms of the
// GNU General Public License version 2 or any later version.

//! Bindings for the `hg::dirstate::dirstate_map` file provided by the
//! `hg-core` package.

use std::cell::{Ref, RefCell};
use std::convert::TryInto;
use std::time::Duration;

use cpython::{
    exc, ObjectProtocol, PyBool, PyBytes, PyClone, PyDict, PyErr, PyObject,
    PyResult, PyTuple, Python, PythonObject, ToPyObject,
};

use crate::{
    dirstate::copymap::{CopyMap, CopyMapItemsIterator, CopyMapKeysIterator},
    dirstate::{dirs_multiset::Dirs, make_dirstate_tuple},
    ref_sharing::{PyLeaked, PySharedRefCell},
};
use hg::{
    utils::hg_path::{HgPath, HgPathBuf},
    DirsMultiset, DirstateEntry, DirstateMap as RustDirstateMap,
    DirstateMapError, DirstateParents, DirstateParseError, EntryState,
    StateMapIter, PARENT_SIZE,
};

// TODO
//     This object needs to share references to multiple members of its Rust
//     inner struct, namely `copy_map`, `dirs` and `all_dirs`.
//     Right now `CopyMap` is done, but it needs to have an explicit reference
//     to `RustDirstateMap` which itself needs to have an encapsulation for
//     every method in `CopyMap` (copymapcopy, etc.).
//     This is ugly and hard to maintain.
//     The same logic applies to `dirs` and `all_dirs`, however the `Dirs`
//     `py_class!` is already implemented and does not mention
//     `RustDirstateMap`, rightfully so.
//     All attributes also have to have a separate refcount data attribute for
//     leaks, with all methods that go along for reference sharing.
py_class!(pub class DirstateMap |py| {
    data inner: PySharedRefCell<RustDirstateMap>;

    def __new__(_cls, _root: PyObject) -> PyResult<Self> {
        let inner = RustDirstateMap::default();
        Self::create_instance(
            py,
            PySharedRefCell::new(inner),
        )
    }

    def clear(&self) -> PyResult<PyObject> {
        self.inner_shared(py).borrow_mut().clear();
        Ok(py.None())
    }

    def get(
        &self,
        key: PyObject,
        default: Option<PyObject> = None
    ) -> PyResult<Option<PyObject>> {
        let key = key.extract::<PyBytes>(py)?;
        match self.inner_shared(py).borrow().get(HgPath::new(key.data(py))) {
            Some(entry) => {
                Ok(Some(make_dirstate_tuple(py, entry)?))
            },
            None => Ok(default)
        }
    }

    def addfile(
        &self,
        f: PyObject,
        oldstate: PyObject,
        state: PyObject,
        mode: PyObject,
        size: PyObject,
        mtime: PyObject
    ) -> PyResult<PyObject> {
        self.inner_shared(py).borrow_mut().add_file(
            HgPath::new(f.extract::<PyBytes>(py)?.data(py)),
            oldstate.extract::<PyBytes>(py)?.data(py)[0]
                .try_into()
                .map_err(|e: DirstateParseError| {
                    PyErr::new::<exc::ValueError, _>(py, e.to_string())
                })?,
            DirstateEntry {
                state: state.extract::<PyBytes>(py)?.data(py)[0]
                    .try_into()
                    .map_err(|e: DirstateParseError| {
                        PyErr::new::<exc::ValueError, _>(py, e.to_string())
                    })?,
                mode: mode.extract(py)?,
                size: size.extract(py)?,
                mtime: mtime.extract(py)?,
            },
        ).and(Ok(py.None())).or_else(|e: DirstateMapError| {
            Err(PyErr::new::<exc::ValueError, _>(py, e.to_string()))
        })
    }

    def removefile(
        &self,
        f: PyObject,
        oldstate: PyObject,
        size: PyObject
    ) -> PyResult<PyObject> {
        self.inner_shared(py).borrow_mut()
            .remove_file(
                HgPath::new(f.extract::<PyBytes>(py)?.data(py)),
                oldstate.extract::<PyBytes>(py)?.data(py)[0]
                    .try_into()
                    .map_err(|e: DirstateParseError| {
                        PyErr::new::<exc::ValueError, _>(py, e.to_string())
                    })?,
                size.extract(py)?,
            )
            .or_else(|_| {
                Err(PyErr::new::<exc::OSError, _>(
                    py,
                    "Dirstate error".to_string(),
                ))
            })?;
        Ok(py.None())
    }

    def dropfile(
        &self,
        f: PyObject,
        oldstate: PyObject
    ) -> PyResult<PyBool> {
        self.inner_shared(py).borrow_mut()
            .drop_file(
                HgPath::new(f.extract::<PyBytes>(py)?.data(py)),
                oldstate.extract::<PyBytes>(py)?.data(py)[0]
                    .try_into()
                    .map_err(|e: DirstateParseError| {
                        PyErr::new::<exc::ValueError, _>(py, e.to_string())
                    })?,
            )
            .and_then(|b| Ok(b.to_py_object(py)))
            .or_else(|_| {
                Err(PyErr::new::<exc::OSError, _>(
                    py,
                    "Dirstate error".to_string(),
                ))
            })
    }

    def clearambiguoustimes(
        &self,
        files: PyObject,
        now: PyObject
    ) -> PyResult<PyObject> {
        let files: PyResult<Vec<HgPathBuf>> = files
            .iter(py)?
            .map(|filename| {
                Ok(HgPathBuf::from_bytes(
                    filename?.extract::<PyBytes>(py)?.data(py),
                ))
            })
            .collect();
        self.inner_shared(py).borrow_mut()
            .clear_ambiguous_times(files?, now.extract(py)?);
        Ok(py.None())
    }

    // TODO share the reference
    def nonnormalentries(&self) -> PyResult<PyObject> {
        let (non_normal, other_parent) =
            self.inner_shared(py).borrow().non_normal_other_parent_entries();

        let locals = PyDict::new(py);
        locals.set_item(
            py,
            "non_normal",
            non_normal
                .iter()
                .map(|v| PyBytes::new(py, v.as_ref()))
                .collect::<Vec<PyBytes>>()
                .to_py_object(py),
        )?;
        locals.set_item(
            py,
            "other_parent",
            other_parent
                .iter()
                .map(|v| PyBytes::new(py, v.as_ref()))
                .collect::<Vec<PyBytes>>()
                .to_py_object(py),
        )?;

        py.eval("set(non_normal), set(other_parent)", None, Some(&locals))
    }

    def hastrackeddir(&self, d: PyObject) -> PyResult<PyBool> {
        let d = d.extract::<PyBytes>(py)?;
        Ok(self.inner_shared(py).borrow_mut()
            .has_tracked_dir(HgPath::new(d.data(py)))
            .map_err(|e| {
                PyErr::new::<exc::ValueError, _>(py, e.to_string())
            })?
            .to_py_object(py))
    }

    def hasdir(&self, d: PyObject) -> PyResult<PyBool> {
        let d = d.extract::<PyBytes>(py)?;
        Ok(self.inner_shared(py).borrow_mut()
            .has_dir(HgPath::new(d.data(py)))
            .map_err(|e| {
                PyErr::new::<exc::ValueError, _>(py, e.to_string())
            })?
            .to_py_object(py))
    }

    def parents(&self, st: PyObject) -> PyResult<PyTuple> {
        self.inner_shared(py).borrow_mut()
            .parents(st.extract::<PyBytes>(py)?.data(py))
            .and_then(|d| {
                Ok((PyBytes::new(py, &d.p1), PyBytes::new(py, &d.p2))
                    .to_py_object(py))
            })
            .or_else(|_| {
                Err(PyErr::new::<exc::OSError, _>(
                    py,
                    "Dirstate error".to_string(),
                ))
            })
    }

    def setparents(&self, p1: PyObject, p2: PyObject) -> PyResult<PyObject> {
        let p1 = extract_node_id(py, &p1)?;
        let p2 = extract_node_id(py, &p2)?;

        self.inner_shared(py).borrow_mut()
            .set_parents(&DirstateParents { p1, p2 });
        Ok(py.None())
    }

    def read(&self, st: PyObject) -> PyResult<Option<PyObject>> {
        match self.inner_shared(py).borrow_mut()
            .read(st.extract::<PyBytes>(py)?.data(py))
        {
            Ok(Some(parents)) => Ok(Some(
                (PyBytes::new(py, &parents.p1), PyBytes::new(py, &parents.p2))
                    .to_py_object(py)
                    .into_object(),
            )),
            Ok(None) => Ok(Some(py.None())),
            Err(_) => Err(PyErr::new::<exc::OSError, _>(
                py,
                "Dirstate error".to_string(),
            )),
        }
    }
    def write(
        &self,
        p1: PyObject,
        p2: PyObject,
        now: PyObject
    ) -> PyResult<PyBytes> {
        let now = Duration::new(now.extract(py)?, 0);
        let parents = DirstateParents {
            p1: extract_node_id(py, &p1)?,
            p2: extract_node_id(py, &p2)?,
        };

        match self.inner_shared(py).borrow_mut().pack(parents, now) {
            Ok(packed) => Ok(PyBytes::new(py, &packed)),
            Err(_) => Err(PyErr::new::<exc::OSError, _>(
                py,
                "Dirstate error".to_string(),
            )),
        }
    }

    def filefoldmapasdict(&self) -> PyResult<PyDict> {
        let dict = PyDict::new(py);
        for (key, value) in
            self.inner_shared(py).borrow_mut().build_file_fold_map().iter()
        {
            dict.set_item(py, key.as_ref().to_vec(), value.as_ref().to_vec())?;
        }
        Ok(dict)
    }

    def __len__(&self) -> PyResult<usize> {
        Ok(self.inner_shared(py).borrow().len())
    }

    def __contains__(&self, key: PyObject) -> PyResult<bool> {
        let key = key.extract::<PyBytes>(py)?;
        Ok(self.inner_shared(py).borrow().contains_key(HgPath::new(key.data(py))))
    }

    def __getitem__(&self, key: PyObject) -> PyResult<PyObject> {
        let key = key.extract::<PyBytes>(py)?;
        let key = HgPath::new(key.data(py));
        match self.inner_shared(py).borrow().get(key) {
            Some(entry) => {
                Ok(make_dirstate_tuple(py, entry)?)
            },
            None => Err(PyErr::new::<exc::KeyError, _>(
                py,
                String::from_utf8_lossy(key.as_bytes()),
            )),
        }
    }

    def keys(&self) -> PyResult<DirstateMapKeysIterator> {
        let leaked_ref = self.inner_shared(py).leak_immutable();
        DirstateMapKeysIterator::from_inner(
            py,
            unsafe { leaked_ref.map(py, |o| o.iter()) },
        )
    }

    def items(&self) -> PyResult<DirstateMapItemsIterator> {
        let leaked_ref = self.inner_shared(py).leak_immutable();
        DirstateMapItemsIterator::from_inner(
            py,
            unsafe { leaked_ref.map(py, |o| o.iter()) },
        )
    }

    def __iter__(&self) -> PyResult<DirstateMapKeysIterator> {
        let leaked_ref = self.inner_shared(py).leak_immutable();
        DirstateMapKeysIterator::from_inner(
            py,
            unsafe { leaked_ref.map(py, |o| o.iter()) },
        )
    }

    def getdirs(&self) -> PyResult<Dirs> {
        // TODO don't copy, share the reference
        self.inner_shared(py).borrow_mut().set_dirs()
            .map_err(|e| {
                PyErr::new::<exc::ValueError, _>(py, e.to_string())
            })?;
        Dirs::from_inner(
            py,
            DirsMultiset::from_dirstate(
                &self.inner_shared(py).borrow(),
                Some(EntryState::Removed),
            )
            .map_err(|e| {
                PyErr::new::<exc::ValueError, _>(py, e.to_string())
            })?,
        )
    }
    def getalldirs(&self) -> PyResult<Dirs> {
        // TODO don't copy, share the reference
        self.inner_shared(py).borrow_mut().set_all_dirs()
            .map_err(|e| {
                PyErr::new::<exc::ValueError, _>(py, e.to_string())
            })?;
        Dirs::from_inner(
            py,
            DirsMultiset::from_dirstate(
                &self.inner_shared(py).borrow(),
                None,
            ).map_err(|e| {
                PyErr::new::<exc::ValueError, _>(py, e.to_string())
            })?,
        )
    }

    // TODO all copymap* methods, see docstring above
    def copymapcopy(&self) -> PyResult<PyDict> {
        let dict = PyDict::new(py);
        for (key, value) in self.inner_shared(py).borrow().copy_map.iter() {
            dict.set_item(
                py,
                PyBytes::new(py, key.as_ref()),
                PyBytes::new(py, value.as_ref()),
            )?;
        }
        Ok(dict)
    }

    def copymapgetitem(&self, key: PyObject) -> PyResult<PyBytes> {
        let key = key.extract::<PyBytes>(py)?;
        match self.inner_shared(py).borrow().copy_map.get(HgPath::new(key.data(py))) {
            Some(copy) => Ok(PyBytes::new(py, copy.as_ref())),
            None => Err(PyErr::new::<exc::KeyError, _>(
                py,
                String::from_utf8_lossy(key.data(py)),
            )),
        }
    }
    def copymap(&self) -> PyResult<CopyMap> {
        CopyMap::from_inner(py, self.clone_ref(py))
    }

    def copymaplen(&self) -> PyResult<usize> {
        Ok(self.inner_shared(py).borrow().copy_map.len())
    }
    def copymapcontains(&self, key: PyObject) -> PyResult<bool> {
        let key = key.extract::<PyBytes>(py)?;
        Ok(self
            .inner_shared(py)
            .borrow()
            .copy_map
            .contains_key(HgPath::new(key.data(py))))
    }
    def copymapget(
        &self,
        key: PyObject,
        default: Option<PyObject>
    ) -> PyResult<Option<PyObject>> {
        let key = key.extract::<PyBytes>(py)?;
        match self
            .inner_shared(py)
            .borrow()
            .copy_map
            .get(HgPath::new(key.data(py)))
        {
            Some(copy) => Ok(Some(
                PyBytes::new(py, copy.as_ref()).into_object(),
            )),
            None => Ok(default),
        }
    }
    def copymapsetitem(
        &self,
        key: PyObject,
        value: PyObject
    ) -> PyResult<PyObject> {
        let key = key.extract::<PyBytes>(py)?;
        let value = value.extract::<PyBytes>(py)?;
        self.inner_shared(py).borrow_mut().copy_map.insert(
            HgPathBuf::from_bytes(key.data(py)),
            HgPathBuf::from_bytes(value.data(py)),
        );
        Ok(py.None())
    }
    def copymappop(
        &self,
        key: PyObject,
        default: Option<PyObject>
    ) -> PyResult<Option<PyObject>> {
        let key = key.extract::<PyBytes>(py)?;
        match self
            .inner_shared(py)
            .borrow_mut()
            .copy_map
            .remove(HgPath::new(key.data(py)))
        {
            Some(_) => Ok(None),
            None => Ok(default),
        }
    }

    def copymapiter(&self) -> PyResult<CopyMapKeysIterator> {
        let leaked_ref = self.inner_shared(py).leak_immutable();
        CopyMapKeysIterator::from_inner(
            py,
            unsafe { leaked_ref.map(py, |o| o.copy_map.iter()) },
        )
    }

    def copymapitemsiter(&self) -> PyResult<CopyMapItemsIterator> {
        let leaked_ref = self.inner_shared(py).leak_immutable();
        CopyMapItemsIterator::from_inner(
            py,
            unsafe { leaked_ref.map(py, |o| o.copy_map.iter()) },
        )
    }

});

impl DirstateMap {
    pub fn get_inner<'a>(
        &'a self,
        py: Python<'a>,
    ) -> Ref<'a, RustDirstateMap> {
        self.inner_shared(py).borrow()
    }
    fn translate_key(
        py: Python,
        res: (&HgPathBuf, &DirstateEntry),
    ) -> PyResult<Option<PyBytes>> {
        Ok(Some(PyBytes::new(py, res.0.as_ref())))
    }
    fn translate_key_value(
        py: Python,
        res: (&HgPathBuf, &DirstateEntry),
    ) -> PyResult<Option<(PyBytes, PyObject)>> {
        let (f, entry) = res;
        Ok(Some((
            PyBytes::new(py, f.as_ref()),
            make_dirstate_tuple(py, entry)?,
        )))
    }
}

py_shared_ref!(DirstateMap, RustDirstateMap, inner, inner_shared);

py_shared_iterator!(
    DirstateMapKeysIterator,
    PyLeaked<StateMapIter<'static>>,
    DirstateMap::translate_key,
    Option<PyBytes>
);

py_shared_iterator!(
    DirstateMapItemsIterator,
    PyLeaked<StateMapIter<'static>>,
    DirstateMap::translate_key_value,
    Option<(PyBytes, PyObject)>
);

fn extract_node_id(py: Python, obj: &PyObject) -> PyResult<[u8; PARENT_SIZE]> {
    let bytes = obj.extract::<PyBytes>(py)?;
    match bytes.data(py).try_into() {
        Ok(s) => Ok(s),
        Err(e) => Err(PyErr::new::<exc::ValueError, _>(py, e.to_string())),
    }
}