comparison rust/hg-core/src/dirstate_tree/dirstate_map.rs @ 47349:7138c863d0a1

dirstate-v2: Skip readdir in status based on directory mtime

When calling `read_dir` during `status` and the directory is found to be
eligible for caching (see code comments), write the directory’s mtime to the
dirstate. The presence of a directory mtime in the dirstate is meaningful
and indicates eligibility.

When an eligible directory mtime is found in the dirstate and `stat()` shows
that the mtime has not changed, `status` can skip calling `read_dir` again
and instead rely on the names of child nodes in the dirstate tree.

The `tempfile` crate is used to create a temporary file in order to use its
modification time as "current time" with the same truncation as other files
and directories would have in their own modification time.

Differential Revision: https://phab.mercurial-scm.org/D10826

47348:a4de570e61fa

        match self {
            NodeRef::InMemory(_path, node) => {
                Ok(node.data.as_entry().map(|entry| entry.state))
            }
            NodeRef::OnDisk(node) => node.state(),
        }
    }

    pub(super) fn tracked_descendants_count(&self) -> u32 {
        match self {

                return Ok(None);
            }
        }
    }

    fn get_or_insert_node<'tree, 'path>(
        on_disk: &'on_disk [u8],
        root: &'tree mut ChildNodes<'on_disk>,
        path: &'path HgPath,
        to_cow: impl Fn(
            WithBasename<&'path HgPath>,

47349:7138c863d0a1

        match self {
            NodeRef::InMemory(_path, node) => {
                Ok(node.data.as_entry().map(|entry| entry.state))
            }
            NodeRef::OnDisk(node) => node.state(),
        }
    }

    pub(super) fn cached_directory_mtime(
        &self,
    ) -> Option<&on_disk::Timestamp> {
        match self {
            NodeRef::InMemory(_path, node) => match &node.data {
                NodeData::CachedDirectory { mtime } => Some(mtime),
                _ => None,
            },
            NodeRef::OnDisk(node) => node.cached_directory_mtime(),
        }
    }

    pub(super) fn tracked_descendants_count(&self) -> u32 {
        match self {

                return Ok(None);
            }
        }
    }

    pub(super) fn get_or_insert_node<'tree, 'path>(
        on_disk: &'on_disk [u8],
        root: &'tree mut ChildNodes<'on_disk>,
        path: &'path HgPath,
        to_cow: impl Fn(
            WithBasename<&'path HgPath>,