comparison rust/hg-core/src/revlog/mod.rs @ 50985:363620b934aa stable

revlog: fix a bug where NULL_NODE failed to be resolved to NULL_REV

The problem is that nodemap already takes care about NULL_NODE
resolution (in `validate_candidate` in `nodemap.rs`), so the special
handling in `rev_from_node` is unnecessary and incorrect.

50984:2dcb6a6c7540

    /// revlog
    pub fn rev_from_node(
        &self,
        node: NodePrefix,
    ) -> Result<Revision, RevlogError> {
        let looked_up = if let Some(nodemap) = &self.nodemap {
            nodemap
                .find_bin(&self.index, node)?
                .ok_or(RevlogError::InvalidRevision)
        } else {
            self.rev_from_node_no_persistent_nodemap(node)
        };

        if node.is_prefix_of(&NULL_NODE) {
            return match looked_up {
                Ok(_) => Err(RevlogError::AmbiguousPrefix),
                Err(RevlogError::InvalidRevision) => Ok(NULL_REVISION),
                res => res,
            };
        };

        looked_up
    }

    /// Same as `rev_from_node`, without using a persistent nodemap
    ///
    /// This is used as fallback when a persistent nodemap is not present.

    ) -> Result<Revision, RevlogError> {
        // Linear scan of the revlog
        // TODO: consider building a non-persistent nodemap in memory to
        // optimize these cases.
        let mut found_by_prefix = None;
        for rev in (0..self.len() as Revision).rev() {
            let index_entry = self.index.get_entry(rev).ok_or_else(|| {
                HgError::corrupted(
                    "revlog references a revision not in the index",
                )
            })?;
            if node == *index_entry.hash() {
                return Ok(rev);
            }
            if node.is_prefix_of(index_entry.hash()) {
                if found_by_prefix.is_some() {
                    return Err(RevlogError::AmbiguousPrefix);
                }
                found_by_prefix = Some(rev)
            }

50985:363620b934aa

    /// revlog
    pub fn rev_from_node(
        &self,
        node: NodePrefix,
    ) -> Result<Revision, RevlogError> {
        if let Some(nodemap) = &self.nodemap {
            nodemap
                .find_bin(&self.index, node)?
                .ok_or(RevlogError::InvalidRevision)
        } else {
            self.rev_from_node_no_persistent_nodemap(node)
        }
    }

    /// Same as `rev_from_node`, without using a persistent nodemap
    ///
    /// This is used as fallback when a persistent nodemap is not present.

    ) -> Result<Revision, RevlogError> {
        // Linear scan of the revlog
        // TODO: consider building a non-persistent nodemap in memory to
        // optimize these cases.
        let mut found_by_prefix = None;
        for rev in (-1..self.len() as Revision).rev() {
            let candidate_node = if rev == -1 {
                NULL_NODE
            } else {
                let index_entry =
                    self.index.get_entry(rev).ok_or_else(|| {
                        HgError::corrupted(
                            "revlog references a revision not in the index",
                        )
                    })?;
                *index_entry.hash()
            };
            if node == candidate_node {
                return Ok(rev);
            }
            if node.is_prefix_of(&candidate_node) {
                if found_by_prefix.is_some() {
                    return Err(RevlogError::AmbiguousPrefix);
                }
                found_by_prefix = Some(rev)
            }