comparison rust/hg-core/src/repo.rs @ 50658:1e2c6cda2309 stable

rust-dirstate: rename `has_dirstate_v2` to `use_dirstate_v2`

It is closer to the right semantics. I added a docstring to better explain
the reasonning. In the next patch(es), I will address the underlying issue
of finding the "wrong" version of the dirstate on disk.

50657:e77ca247b85b

        f: impl FnOnce() -> R,
    ) -> Result<R, LockError> {
        try_with_lock_no_wait(self.hg_vfs(), "wlock", f)
    }

    pub fn has_dirstate_v2(&self) -> bool {
        self.requirements
            .contains(requirements::DIRSTATE_V2_REQUIREMENT)
    }

    pub fn has_sparse(&self) -> bool {

    fn read_dirstate_parents(&self) -> Result<DirstateParents, HgError> {
        let dirstate = self.dirstate_file_contents()?;
        let parents = if dirstate.is_empty() {
            DirstateParents::NULL
        } else if self.has_dirstate_v2() {
            let docket =
                crate::dirstate_tree::on_disk::read_docket(&dirstate)?;
            docket.parents()
        } else {
            *crate::dirstate::parsers::parse_dirstate_parents(&dirstate)?

    /// Namely, the inode, data file uuid and the data size.
    fn get_dirstate_data_file_integrity(
        &self,
    ) -> Result<DirstateMapIdentity, HgError> {
        assert!(
            self.has_dirstate_v2(),
            "accessing dirstate data file ID without dirstate-v2"
        );
        // Get the identity before the contents since we could have a race
        // between the two. Having an identity that is too old is fine, but
        // one that is younger than the content change is bad.

            Ok((identity, Some(docket.uuid.to_owned()), docket.data_size()))
        }
    }

    fn new_dirstate_map(&self) -> Result<OwningDirstateMap, DirstateError> {
        if self.has_dirstate_v2() {
            // The v2 dirstate is split into a docket and a data file.
            // Since we don't always take the `wlock` to read it
            // (like in `hg status`), it is susceptible to races.
            // A simple retry method should be enough since full rewrites
            // only happen when too much garbage data is present and

    pub fn write_dirstate(&self) -> Result<(), DirstateError> {
        let map = self.dirstate_map()?;
        // TODO: Maintain a `DirstateMap::dirty` flag, and return early here if
        // it’s unset
        let parents = self.dirstate_parents()?;
        let (packed_dirstate, old_uuid_to_remove) = if self.has_dirstate_v2() {
            let (identity, uuid, data_size) =
                self.get_dirstate_data_file_integrity()?;
            let identity_changed = identity != map.old_identity();
            let uuid_changed = uuid.as_deref() != map.old_uuid();
            let data_length_changed = data_size != map.old_data_size();

50658:1e2c6cda2309

        f: impl FnOnce() -> R,
    ) -> Result<R, LockError> {
        try_with_lock_no_wait(self.hg_vfs(), "wlock", f)
    }

    /// Whether this repo should use dirstate-v2.
    /// The presence of `dirstate-v2` in the requirements does not mean that
    /// the on-disk dirstate is necessarily in version 2. In most cases,
    /// a dirstate-v2 file will indeed be found, but in rare cases (like the
    /// upgrade mechanism being cut short), the on-disk version will be a
    /// v1 file.
    /// Semantically, having a requirement only means that a client should be
    /// able to understand the repo *if* it uses the requirement, but not that
    /// the requirement is actually used.
    pub fn use_dirstate_v2(&self) -> bool {
        self.requirements
            .contains(requirements::DIRSTATE_V2_REQUIREMENT)
    }

    pub fn has_sparse(&self) -> bool {

    fn read_dirstate_parents(&self) -> Result<DirstateParents, HgError> {
        let dirstate = self.dirstate_file_contents()?;
        let parents = if dirstate.is_empty() {
            DirstateParents::NULL
        } else if self.use_dirstate_v2() {
            let docket =
                crate::dirstate_tree::on_disk::read_docket(&dirstate)?;
            docket.parents()
        } else {
            *crate::dirstate::parsers::parse_dirstate_parents(&dirstate)?

    /// Namely, the inode, data file uuid and the data size.
    fn get_dirstate_data_file_integrity(
        &self,
    ) -> Result<DirstateMapIdentity, HgError> {
        assert!(
            self.use_dirstate_v2(),
            "accessing dirstate data file ID without dirstate-v2"
        );
        // Get the identity before the contents since we could have a race
        // between the two. Having an identity that is too old is fine, but
        // one that is younger than the content change is bad.

            Ok((identity, Some(docket.uuid.to_owned()), docket.data_size()))
        }
    }

    fn new_dirstate_map(&self) -> Result<OwningDirstateMap, DirstateError> {
        if self.use_dirstate_v2() {
            // The v2 dirstate is split into a docket and a data file.
            // Since we don't always take the `wlock` to read it
            // (like in `hg status`), it is susceptible to races.
            // A simple retry method should be enough since full rewrites
            // only happen when too much garbage data is present and

    pub fn write_dirstate(&self) -> Result<(), DirstateError> {
        let map = self.dirstate_map()?;
        // TODO: Maintain a `DirstateMap::dirty` flag, and return early here if
        // it’s unset
        let parents = self.dirstate_parents()?;
        let (packed_dirstate, old_uuid_to_remove) = if self.use_dirstate_v2() {
            let (identity, uuid, data_size) =
                self.get_dirstate_data_file_integrity()?;
            let identity_changed = identity != map.old_identity();
            let uuid_changed = uuid.as_deref() != map.old_uuid();
            let data_length_changed = data_size != map.old_data_size();