status: Extend read_dir caching to directories with ignored files

See code comments

Differential Revision: https://phab.mercurial-scm.org/D10909

rust/hg-core/src/dirstate_tree/on_disk.rs

@@ -1,600 +1,603 b''
 //! The "version 2" disk representation of the dirstate
 //!
 //! # File format
 //!
 //! The file starts with a fixed-sized header, whose layout is defined by the
 //! `Header` struct. Its `root` field contains the slice (offset and length) to
 //! the nodes representing the files and directories at the root of the
 //! repository. Each node is also fixed-size, defined by the `Node` struct.
 //! Nodes in turn contain slices to variable-size paths, and to their own child
 //! nodes (if any) for nested files and directories.
 
 use crate::dirstate_tree::dirstate_map::{self, DirstateMap, NodeRef};
 use crate::dirstate_tree::path_with_basename::WithBasename;
 use crate::errors::HgError;
 use crate::utils::hg_path::HgPath;
 use crate::DirstateEntry;
 use crate::DirstateError;
 use crate::DirstateParents;
 use crate::EntryState;
 use bytes_cast::unaligned::{I32Be, I64Be, U32Be, U64Be};
 use bytes_cast::BytesCast;
 use std::borrow::Cow;
 use std::convert::TryFrom;
 use std::time::{Duration, SystemTime, UNIX_EPOCH};
 
 /// Added at the start of `.hg/dirstate` when the "v2" format is used.
 /// This a redundant sanity check more than an actual "magic number" since
 /// `.hg/requires` already governs which format should be used.
 pub const V2_FORMAT_MARKER: &[u8; 12] = b"dirstate-v2\n";
 
 pub(super) const IGNORE_PATTERNS_HASH_LEN: usize = 20;
 pub(super) type IgnorePatternsHash = [u8; IGNORE_PATTERNS_HASH_LEN];
 
 #[derive(BytesCast)]
 #[repr(C)]
 struct Header {
     marker: [u8; V2_FORMAT_MARKER.len()],
 
     /// `dirstatemap.parents()` in `mercurial/dirstate.py` relies on this
     /// `parents` field being at this offset, immediately after `marker`.
     parents: DirstateParents,
 
     root: ChildNodes,
     nodes_with_entry_count: Size,
     nodes_with_copy_source_count: Size,
 
     /// If non-zero, a hash of ignore files that were used for some previous
     /// run of the `status` algorithm.
     ///
     /// We define:
     ///
     /// * "Root" ignore files are `.hgignore` at the root of the repository if
     ///   it exists, and files from `ui.ignore.*` config. This set of files is
     ///   then sorted by the string representation of their path.
     /// * The "expanded contents" of an ignore files is the byte string made
     ///   by concatenating its contents with the "expanded contents" of other
     ///   files included with `include:` or `subinclude:` files, in inclusion
     ///   order. This definition is recursive, as included files can
     ///   themselves include more files.
     ///
     /// This hash is defined as the SHA-1 of the concatenation (in sorted
     /// order) of the "expanded contents" of each "root" ignore file.
     /// (Note that computing this does not require actually concatenating byte
     /// strings into contiguous memory, instead SHA-1 hashing can be done
     /// incrementally.)
     ignore_patterns_hash: IgnorePatternsHash,
 }
 
 #[derive(BytesCast)]
 #[repr(C)]
 pub(super) struct Node {
     full_path: PathSlice,
 
     /// In bytes from `self.full_path.start`
     base_name_start: Size,
 
     copy_source: OptPathSlice,
     children: ChildNodes,
     pub(super) tracked_descendants_count: Size,
 
     /// Dependending on the value of `state`:
     ///
     /// * A null byte: `data` is not used.
     ///
     /// * A `n`, `a`, `r`, or `m` ASCII byte: `state` and `data` together
     ///   represent a dirstate entry like in the v1 format.
     ///
     /// * A `d` ASCII byte: the bytes of `data` should instead be interpreted
     ///   as the `Timestamp` for the mtime of a cached directory.
     ///
     ///   The presence of this state means that at some point, this path in
     ///   the working directory was observed:
     ///
     ///   - To be a directory
     ///   - With the modification time as given by `Timestamp`
     ///   - That timestamp was already strictly in the past when observed,
     ///     meaning that later changes cannot happen in the same clock tick
     ///     and must cause a different modification time (unless the system
     ///     clock jumps back and we get unlucky, which is not impossible but
     ///     but deemed unlikely enough).
-    ///   - The directory did not contain any child entry that did not have a
-    ///     corresponding dirstate node.
+    ///   - All direct children of this directory (as returned by
+    ///     `std::fs::read_dir`) either have a corresponding dirstate node, or
+    ///     are ignored by ignore patterns whose hash is in
+    ///     `Header::ignore_patterns_hash`.
     ///
     ///   This means that if `std::fs::symlink_metadata` later reports the
-    ///   same modification time, we don’t need to call `std::fs::read_dir`
-    ///   again for this directory and can iterate child dirstate nodes
-    ///   instead.
+    ///   same modification time and ignored patterns haven’t changed, a run
+    ///   of status that is not listing ignored   files can skip calling
+    ///   `std::fs::read_dir` again for this directory,   iterate child
+    ///   dirstate nodes instead.
     state: u8,
     data: Entry,
 }
 
 #[derive(BytesCast, Copy, Clone)]
 #[repr(C)]
 struct Entry {
     mode: I32Be,
     mtime: I32Be,
     size: I32Be,
 }
 
 /// Duration since the Unix epoch
 #[derive(BytesCast, Copy, Clone, PartialEq)]
 #[repr(C)]
 pub(super) struct Timestamp {
     seconds: I64Be,
 
     /// In `0 .. 1_000_000_000`.
     ///
     /// This timestamp is later or earlier than `(seconds, 0)` by this many
     /// nanoseconds, if `seconds` is non-negative or negative, respectively.
     nanoseconds: U32Be,
 }
 
 /// Counted in bytes from the start of the file
 ///
 /// NOTE: If we decide to never support `.hg/dirstate` files larger than 4 GiB
 /// we could save space by using `U32Be` instead.
 type Offset = U64Be;
 
 /// Counted in number of items
 ///
 /// NOTE: not supporting directories with more than 4 billion direct children,
 /// or filenames more than 4 GiB.
 type Size = U32Be;
 
 /// Location of consecutive, fixed-size items.
 ///
 /// An item can be a single byte for paths, or a struct with
 /// `derive(BytesCast)`.
 #[derive(BytesCast, Copy, Clone)]
 #[repr(C)]
 struct Slice {
     start: Offset,
     len: Size,
 }
 
 /// A contiguous sequence of `len` times `Node`, representing the child nodes
 /// of either some other node or of the repository root.
 ///
 /// Always sorted by ascending `full_path`, to allow binary search.
 /// Since nodes with the same parent nodes also have the same parent path,
 /// only the `base_name`s need to be compared during binary search.
 type ChildNodes = Slice;
 
 /// A `HgPath` of `len` bytes
 type PathSlice = Slice;
 
 /// Either nothing if `start == 0`, or a `HgPath` of `len` bytes
 type OptPathSlice = Slice;
 
 /// Make sure that size-affecting changes are made knowingly
 fn _static_assert_size_of() {
     let _ = std::mem::transmute::<Header, [u8; 92]>;
     let _ = std::mem::transmute::<Node, [u8; 57]>;
 }
 
 /// Unexpected file format found in `.hg/dirstate` with the "v2" format.
 ///
 /// This should only happen if Mercurial is buggy or a repository is corrupted.
 #[derive(Debug)]
 pub struct DirstateV2ParseError;
 
 impl From<DirstateV2ParseError> for HgError {
     fn from(_: DirstateV2ParseError) -> Self {
         HgError::corrupted("dirstate-v2 parse error")
     }
 }
 
 impl From<DirstateV2ParseError> for crate::DirstateError {
     fn from(error: DirstateV2ParseError) -> Self {
         HgError::from(error).into()
     }
 }
 
 fn read_header(on_disk: &[u8]) -> Result<&Header, DirstateV2ParseError> {
     let (header, _) =
         Header::from_bytes(on_disk).map_err(|_| DirstateV2ParseError)?;
     if header.marker == *V2_FORMAT_MARKER {
         Ok(header)
     } else {
         Err(DirstateV2ParseError)
     }
 }
 
 pub(super) fn read<'on_disk>(
     on_disk: &'on_disk [u8],
 ) -> Result<
     (DirstateMap<'on_disk>, Option<DirstateParents>),
     DirstateV2ParseError,
 > {
     if on_disk.is_empty() {
         return Ok((DirstateMap::empty(on_disk), None));
     }
     let header = read_header(on_disk)?;
     let dirstate_map = DirstateMap {
         on_disk,
         root: dirstate_map::ChildNodes::OnDisk(read_slice::<Node>(
             on_disk,
             header.root,
         )?),
         nodes_with_entry_count: header.nodes_with_entry_count.get(),
         nodes_with_copy_source_count: header
             .nodes_with_copy_source_count
             .get(),
         ignore_patterns_hash: header.ignore_patterns_hash,
     };
     let parents = Some(header.parents.clone());
     Ok((dirstate_map, parents))
 }
 
 impl Node {
     pub(super) fn full_path<'on_disk>(
         &self,
         on_disk: &'on_disk [u8],
     ) -> Result<&'on_disk HgPath, DirstateV2ParseError> {
         read_hg_path(on_disk, self.full_path)
     }
 
     pub(super) fn base_name_start<'on_disk>(
         &self,
     ) -> Result<usize, DirstateV2ParseError> {
         let start = self.base_name_start.get();
         if start < self.full_path.len.get() {
             let start = usize::try_from(start)
                 // u32 -> usize, could only panic on a 16-bit CPU
                 .expect("dirstate-v2 base_name_start out of bounds");
             Ok(start)
         } else {
             Err(DirstateV2ParseError)
         }
     }
 
     pub(super) fn base_name<'on_disk>(
         &self,
         on_disk: &'on_disk [u8],
     ) -> Result<&'on_disk HgPath, DirstateV2ParseError> {
         let full_path = self.full_path(on_disk)?;
         let base_name_start = self.base_name_start()?;
         Ok(HgPath::new(&full_path.as_bytes()[base_name_start..]))
     }
 
     pub(super) fn path<'on_disk>(
         &self,
         on_disk: &'on_disk [u8],
     ) -> Result<dirstate_map::NodeKey<'on_disk>, DirstateV2ParseError> {
         Ok(WithBasename::from_raw_parts(
             Cow::Borrowed(self.full_path(on_disk)?),
             self.base_name_start()?,
         ))
     }
 
     pub(super) fn has_copy_source<'on_disk>(&self) -> bool {
         self.copy_source.start.get() != 0
     }
 
     pub(super) fn copy_source<'on_disk>(
         &self,
         on_disk: &'on_disk [u8],
     ) -> Result<Option<&'on_disk HgPath>, DirstateV2ParseError> {
         Ok(if self.has_copy_source() {
             Some(read_hg_path(on_disk, self.copy_source)?)
         } else {
             None
         })
     }
 
     pub(super) fn node_data(
         &self,
     ) -> Result<dirstate_map::NodeData, DirstateV2ParseError> {
         let entry = |state| {
             dirstate_map::NodeData::Entry(self.entry_with_given_state(state))
         };
 
         match self.state {
             b'\0' => Ok(dirstate_map::NodeData::None),
             b'd' => Ok(dirstate_map::NodeData::CachedDirectory {
                 mtime: *self.data.as_timestamp(),
             }),
             b'n' => Ok(entry(EntryState::Normal)),
             b'a' => Ok(entry(EntryState::Added)),
             b'r' => Ok(entry(EntryState::Removed)),
             b'm' => Ok(entry(EntryState::Merged)),
             _ => Err(DirstateV2ParseError),
         }
     }
 
     pub(super) fn cached_directory_mtime(&self) -> Option<&Timestamp> {
         if self.state == b'd' {
             Some(self.data.as_timestamp())
         } else {
             None
         }
     }
 
     pub(super) fn state(
         &self,
     ) -> Result<Option<EntryState>, DirstateV2ParseError> {
         match self.state {
             b'\0' | b'd' => Ok(None),
             b'n' => Ok(Some(EntryState::Normal)),
             b'a' => Ok(Some(EntryState::Added)),
             b'r' => Ok(Some(EntryState::Removed)),
             b'm' => Ok(Some(EntryState::Merged)),
             _ => Err(DirstateV2ParseError),
         }
     }
 
     fn entry_with_given_state(&self, state: EntryState) -> DirstateEntry {
         DirstateEntry {
             state,
             mode: self.data.mode.get(),
             mtime: self.data.mtime.get(),
             size: self.data.size.get(),
         }
     }
 
     pub(super) fn entry(
         &self,
     ) -> Result<Option<DirstateEntry>, DirstateV2ParseError> {
         Ok(self
             .state()?
             .map(|state| self.entry_with_given_state(state)))
     }
 
     pub(super) fn children<'on_disk>(
         &self,
         on_disk: &'on_disk [u8],
     ) -> Result<&'on_disk [Node], DirstateV2ParseError> {
         read_slice::<Node>(on_disk, self.children)
     }
 
     pub(super) fn to_in_memory_node<'on_disk>(
         &self,
         on_disk: &'on_disk [u8],
     ) -> Result<dirstate_map::Node<'on_disk>, DirstateV2ParseError> {
         Ok(dirstate_map::Node {
             children: dirstate_map::ChildNodes::OnDisk(
                 self.children(on_disk)?,
             ),
             copy_source: self.copy_source(on_disk)?.map(Cow::Borrowed),
             data: self.node_data()?,
             tracked_descendants_count: self.tracked_descendants_count.get(),
         })
     }
 }
 
 impl Entry {
     fn from_timestamp(timestamp: Timestamp) -> Self {
         // Safety: both types implement the `ByteCast` trait, so we could
         // safely use `as_bytes` and `from_bytes` to do this conversion. Using
         // `transmute` instead makes the compiler check that the two types
         // have the same size, which eliminates the error case of
         // `from_bytes`.
         unsafe { std::mem::transmute::<Timestamp, Entry>(timestamp) }
     }
 
     fn as_timestamp(&self) -> &Timestamp {
         // Safety: same as above in `from_timestamp`
         unsafe { &*(self as *const Entry as *const Timestamp) }
     }
 }
 
 impl Timestamp {
     pub fn seconds(&self) -> i64 {
         self.seconds.get()
     }
 }
 
 impl From<SystemTime> for Timestamp {
     fn from(system_time: SystemTime) -> Self {
         let (secs, nanos) = match system_time.duration_since(UNIX_EPOCH) {
             Ok(duration) => {
                 (duration.as_secs() as i64, duration.subsec_nanos())
             }
             Err(error) => {
                 let negative = error.duration();
                 (-(negative.as_secs() as i64), negative.subsec_nanos())
             }
         };
         Timestamp {
             seconds: secs.into(),
             nanoseconds: nanos.into(),
         }
     }
 }
 
 impl From<&'_ Timestamp> for SystemTime {
     fn from(timestamp: &'_ Timestamp) -> Self {
         let secs = timestamp.seconds.get();
         let nanos = timestamp.nanoseconds.get();
         if secs >= 0 {
             UNIX_EPOCH + Duration::new(secs as u64, nanos)
         } else {
             UNIX_EPOCH - Duration::new((-secs) as u64, nanos)
         }
     }
 }
 
 fn read_hg_path(
     on_disk: &[u8],
     slice: Slice,
 ) -> Result<&HgPath, DirstateV2ParseError> {
     let bytes = read_slice::<u8>(on_disk, slice)?;
     Ok(HgPath::new(bytes))
 }
 
 fn read_slice<T>(
     on_disk: &[u8],
     slice: Slice,
 ) -> Result<&[T], DirstateV2ParseError>
 where
     T: BytesCast,
 {
     // Either `usize::MAX` would result in "out of bounds" error since a single
     // `&[u8]` cannot occupy the entire addess space.
     let start = usize::try_from(slice.start.get()).unwrap_or(std::usize::MAX);
     let len = usize::try_from(slice.len.get()).unwrap_or(std::usize::MAX);
     on_disk
         .get(start..)
         .and_then(|bytes| T::slice_from_bytes(bytes, len).ok())
         .map(|(slice, _rest)| slice)
         .ok_or_else(|| DirstateV2ParseError)
 }
 
 pub(crate) fn parse_dirstate_parents(
     on_disk: &[u8],
 ) -> Result<&DirstateParents, HgError> {
     Ok(&read_header(on_disk)?.parents)
 }
 
 pub(crate) fn for_each_tracked_path<'on_disk>(
     on_disk: &'on_disk [u8],
     mut f: impl FnMut(&'on_disk HgPath),
 ) -> Result<(), DirstateV2ParseError> {
     let header = read_header(on_disk)?;
     fn recur<'on_disk>(
         on_disk: &'on_disk [u8],
         nodes: Slice,
         f: &mut impl FnMut(&'on_disk HgPath),
     ) -> Result<(), DirstateV2ParseError> {
         for node in read_slice::<Node>(on_disk, nodes)? {
             if let Some(state) = node.state()? {
                 if state.is_tracked() {
                     f(node.full_path(on_disk)?)
                 }
             }
             recur(on_disk, node.children, f)?
         }
         Ok(())
     }
     recur(on_disk, header.root, &mut f)
 }
 
 pub(super) fn write(
     dirstate_map: &mut DirstateMap,
     parents: DirstateParents,
 ) -> Result<Vec<u8>, DirstateError> {
     let header_len = std::mem::size_of::<Header>();
 
     // This ignores the space for paths, and for nodes without an entry.
     // TODO: better estimate? Skip the `Vec` and write to a file directly?
     let size_guess = header_len
         + std::mem::size_of::<Node>()
             * dirstate_map.nodes_with_entry_count as usize;
     let mut out = Vec::with_capacity(size_guess);
 
     // Keep space for the header. We’ll fill it out at the end when we know the
     // actual offset for the root nodes.
     out.resize(header_len, 0_u8);
 
     let root =
         write_nodes(dirstate_map, dirstate_map.root.as_ref(), &mut out)?;
 
     let header = Header {
         marker: *V2_FORMAT_MARKER,
         parents: parents,
         root,
         nodes_with_entry_count: dirstate_map.nodes_with_entry_count.into(),
         nodes_with_copy_source_count: dirstate_map
             .nodes_with_copy_source_count
             .into(),
         ignore_patterns_hash: dirstate_map.ignore_patterns_hash,
     };
     out[..header_len].copy_from_slice(header.as_bytes());
     Ok(out)
 }
 
 fn write_nodes(
     dirstate_map: &DirstateMap,
     nodes: dirstate_map::ChildNodesRef,
     out: &mut Vec<u8>,
 ) -> Result<ChildNodes, DirstateError> {
     // `dirstate_map::ChildNodes` is a `HashMap` with undefined iteration
     // order. Sort to enable binary search in the written file.
     let nodes = nodes.sorted();
 
     // First accumulate serialized nodes in a `Vec`
     let mut on_disk_nodes = Vec::with_capacity(nodes.len());
     for node in nodes {
         let children = write_nodes(
             dirstate_map,
             node.children(dirstate_map.on_disk)?,
             out,
         )?;
         let full_path = node.full_path(dirstate_map.on_disk)?;
         let full_path = write_slice::<u8>(full_path.as_bytes(), out);
         let copy_source =
             if let Some(source) = node.copy_source(dirstate_map.on_disk)? {
                 write_slice::<u8>(source.as_bytes(), out)
             } else {
                 Slice {
                     start: 0.into(),
                     len: 0.into(),
                 }
             };
         on_disk_nodes.push(match node {
             NodeRef::InMemory(path, node) => {
                 let (state, data) = match &node.data {
                     dirstate_map::NodeData::Entry(entry) => (
                         entry.state.into(),
                         Entry {
                             mode: entry.mode.into(),
                             mtime: entry.mtime.into(),
                             size: entry.size.into(),
                         },
                     ),
                     dirstate_map::NodeData::CachedDirectory { mtime } => {
                         (b'd', Entry::from_timestamp(*mtime))
                     }
                     dirstate_map::NodeData::None => (
                         b'\0',
                         Entry {
                             mode: 0.into(),
                             mtime: 0.into(),
                             size: 0.into(),
                         },
                     ),
                 };
                 Node {
                     children,
                     copy_source,
                     full_path,
                     base_name_start: u32::try_from(path.base_name_start())
                         // Could only panic for paths over 4 GiB
                         .expect("dirstate-v2 offset overflow")
                         .into(),
                     tracked_descendants_count: node
                         .tracked_descendants_count
                         .into(),
                     state,
                     data,
                 }
             }
             NodeRef::OnDisk(node) => Node {
                 children,
                 copy_source,
                 full_path,
                 ..*node
             },
         })
     }
     // … so we can write them contiguously
     Ok(write_slice::<Node>(&on_disk_nodes, out))
 }
 
 fn write_slice<T>(slice: &[T], out: &mut Vec<u8>) -> Slice
 where
     T: BytesCast,
 {
     let start = u64::try_from(out.len())
         // Could only panic on a 128-bit CPU with a dirstate over 16 EiB
         .expect("dirstate-v2 offset overflow")
         .into();
     let len = u32::try_from(slice.len())
         // Could only panic for paths over 4 GiB or nodes with over 4 billions
         // child nodes
         .expect("dirstate-v2 offset overflow")
         .into();
     out.extend(slice.as_bytes());
     Slice { start, len }
 }

rust/hg-core/src/dirstate_tree/status.rs

@@ -1,728 +1,758 b''
 use crate::dirstate::status::IgnoreFnType;
 use crate::dirstate_tree::dirstate_map::BorrowedPath;
 use crate::dirstate_tree::dirstate_map::ChildNodesRef;
 use crate::dirstate_tree::dirstate_map::DirstateMap;
 use crate::dirstate_tree::dirstate_map::NodeData;
 use crate::dirstate_tree::dirstate_map::NodeRef;
 use crate::dirstate_tree::on_disk::DirstateV2ParseError;
 use crate::dirstate_tree::on_disk::Timestamp;
 use crate::matchers::get_ignore_function;
 use crate::matchers::Matcher;
 use crate::utils::files::get_bytes_from_os_string;
 use crate::utils::files::get_path_from_bytes;
 use crate::utils::hg_path::HgPath;
 use crate::BadMatch;
 use crate::DirstateStatus;
 use crate::EntryState;
 use crate::HgPathBuf;
 use crate::PatternFileWarning;
 use crate::StatusError;
 use crate::StatusOptions;
 use micro_timer::timed;
 use rayon::prelude::*;
 use sha1::{Digest, Sha1};
 use std::borrow::Cow;
 use std::io;
 use std::path::Path;
 use std::path::PathBuf;
 use std::sync::Mutex;
 use std::time::SystemTime;
 
 /// Returns the status of the working directory compared to its parent
 /// changeset.
 ///
 /// This algorithm is based on traversing the filesystem tree (`fs` in function
 /// and variable names) and dirstate tree at the same time. The core of this
 /// traversal is the recursive `traverse_fs_directory_and_dirstate` function
 /// and its use of `itertools::merge_join_by`. When reaching a path that only
 /// exists in one of the two trees, depending on information requested by
 /// `options` we may need to traverse the remaining subtree.
 #[timed]
 pub fn status<'tree, 'on_disk: 'tree>(
     dmap: &'tree mut DirstateMap<'on_disk>,
     matcher: &(dyn Matcher + Sync),
     root_dir: PathBuf,
     ignore_files: Vec<PathBuf>,
     options: StatusOptions,
 ) -> Result<(DirstateStatus<'on_disk>, Vec<PatternFileWarning>), StatusError> {
     let (ignore_fn, warnings, patterns_changed): (IgnoreFnType, _, _) =
         if options.list_ignored || options.list_unknown {
             let mut hasher = Sha1::new();
             let (ignore_fn, warnings) = get_ignore_function(
                 ignore_files,
                 &root_dir,
                 &mut |pattern_bytes| hasher.update(pattern_bytes),
             )?;
             let new_hash = *hasher.finalize().as_ref();
             let changed = new_hash != dmap.ignore_patterns_hash;
             dmap.ignore_patterns_hash = new_hash;
             (ignore_fn, warnings, Some(changed))
         } else {
             (Box::new(|&_| true), vec![], None)
         };
 
     let common = StatusCommon {
         dmap,
         options,
         matcher,
         ignore_fn,
         outcome: Default::default(),
         ignore_patterns_have_changed: patterns_changed,
         new_cachable_directories: Default::default(),
         outated_cached_directories: Default::default(),
         filesystem_time_at_status_start: filesystem_now(&root_dir).ok(),
     };
     let is_at_repo_root = true;
     let hg_path = &BorrowedPath::OnDisk(HgPath::new(""));
     let has_ignored_ancestor = false;
     let root_cached_mtime = None;
     let root_dir_metadata = None;
     // If the path we have for the repository root is a symlink, do follow it.
     // (As opposed to symlinks within the working directory which are not
     // followed, using `std::fs::symlink_metadata`.)
     common.traverse_fs_directory_and_dirstate(
         has_ignored_ancestor,
         dmap.root.as_ref(),
         hg_path,
         &root_dir,
         root_dir_metadata,
         root_cached_mtime,
         is_at_repo_root,
     )?;
     let mut outcome = common.outcome.into_inner().unwrap();
     let new_cachable = common.new_cachable_directories.into_inner().unwrap();
     let outdated = common.outated_cached_directories.into_inner().unwrap();
 
     outcome.dirty = common.ignore_patterns_have_changed == Some(true)
         || !outdated.is_empty()
         || !new_cachable.is_empty();
 
     // Remove outdated mtimes before adding new mtimes, in case a given
     // directory is both
     for path in &outdated {
         let node = dmap.get_or_insert(path)?;
         if let NodeData::CachedDirectory { .. } = &node.data {
             node.data = NodeData::None
         }
     }
     for (path, mtime) in &new_cachable {
         let node = dmap.get_or_insert(path)?;
         match &node.data {
             NodeData::Entry(_) => {} // Don’t overwrite an entry
             NodeData::CachedDirectory { .. } | NodeData::None => {
                 node.data = NodeData::CachedDirectory { mtime: *mtime }
             }
         }
     }
 
     Ok((outcome, warnings))
 }
 
 /// Bag of random things needed by various parts of the algorithm. Reduces the
 /// number of parameters passed to functions.
 struct StatusCommon<'a, 'tree, 'on_disk: 'tree> {
     dmap: &'tree DirstateMap<'on_disk>,
     options: StatusOptions,
     matcher: &'a (dyn Matcher + Sync),
     ignore_fn: IgnoreFnType<'a>,
     outcome: Mutex<DirstateStatus<'on_disk>>,
     new_cachable_directories: Mutex<Vec<(Cow<'on_disk, HgPath>, Timestamp)>>,
     outated_cached_directories: Mutex<Vec<Cow<'on_disk, HgPath>>>,
 
     /// Whether ignore files like `.hgignore` have changed since the previous
     /// time a `status()` call wrote their hash to the dirstate. `None` means
     /// we don’t know as this run doesn’t list either ignored or uknown files
     /// and therefore isn’t reading `.hgignore`.
     ignore_patterns_have_changed: Option<bool>,
 
     /// The current time at the start of the `status()` algorithm, as measured
     /// and possibly truncated by the filesystem.
     filesystem_time_at_status_start: Option<SystemTime>,
 }
 
 impl<'a, 'tree, 'on_disk> StatusCommon<'a, 'tree, 'on_disk> {
     fn read_dir(
         &self,
         hg_path: &HgPath,
         fs_path: &Path,
         is_at_repo_root: bool,
     ) -> Result<Vec<DirEntry>, ()> {
         DirEntry::read_dir(fs_path, is_at_repo_root)
             .map_err(|error| self.io_error(error, hg_path))
     }
 
     fn io_error(&self, error: std::io::Error, hg_path: &HgPath) {
         let errno = error.raw_os_error().expect("expected real OS error");
         self.outcome
             .lock()
             .unwrap()
             .bad
             .push((hg_path.to_owned().into(), BadMatch::OsError(errno)))
     }
 
     fn check_for_outdated_directory_cache(
         &self,
         dirstate_node: &NodeRef<'tree, 'on_disk>,
     ) -> Result<(), DirstateV2ParseError> {
         if self.ignore_patterns_have_changed == Some(true)
             && dirstate_node.cached_directory_mtime().is_some()
         {
             self.outated_cached_directories.lock().unwrap().push(
                 dirstate_node
                     .full_path_borrowed(self.dmap.on_disk)?
                     .detach_from_tree(),
             )
         }
         Ok(())
     }
 
     /// If this returns true, we can get accurate results by only using
     /// `symlink_metadata` for child nodes that exist in the dirstate and don’t
     /// need to call `read_dir`.
     fn can_skip_fs_readdir(
         &self,
         directory_metadata: Option<&std::fs::Metadata>,
         cached_directory_mtime: Option<&Timestamp>,
     ) -> bool {
         if !self.options.list_unknown && !self.options.list_ignored {
             // All states that we care about listing have corresponding
             // dirstate entries.
             // This happens for example with `hg status -mard`.
             return true;
         }
-        if let Some(cached_mtime) = cached_directory_mtime {
-            // The dirstate contains a cached mtime for this directory, set by
-            // a previous run of the `status` algorithm which found this
-            // directory eligible for `read_dir` caching.
-            if let Some(meta) = directory_metadata {
-                if let Ok(current_mtime) = meta.modified() {
-                    if current_mtime == cached_mtime.into() {
-                        // The mtime of that directory has not changed since
-                        // then, which means that the
-                        // results of `read_dir` should also
-                        // be unchanged.
-                        return true;
+        if !self.options.list_ignored
+            && self.ignore_patterns_have_changed == Some(false)
+        {
+            if let Some(cached_mtime) = cached_directory_mtime {
+                // The dirstate contains a cached mtime for this directory, set
+                // by a previous run of the `status` algorithm which found this
+                // directory eligible for `read_dir` caching.
+                if let Some(meta) = directory_metadata {
+                    if let Ok(current_mtime) = meta.modified() {
+                        if current_mtime == cached_mtime.into() {
+                            // The mtime of that directory has not changed
+                            // since then, which means that the results of
+                            // `read_dir` should also be unchanged.
+                            return true;
+                        }
                     }
                 }
             }
         }
         false
     }
 
-    /// Returns whether the filesystem directory was found to have any entry
-    /// that does not have a corresponding dirstate tree node.
+    /// Returns whether all child entries of the filesystem directory have a
+    /// corresponding dirstate node or are ignored.
     fn traverse_fs_directory_and_dirstate(
         &self,
         has_ignored_ancestor: bool,
         dirstate_nodes: ChildNodesRef<'tree, 'on_disk>,
         directory_hg_path: &BorrowedPath<'tree, 'on_disk>,
         directory_fs_path: &Path,
         directory_metadata: Option<&std::fs::Metadata>,
         cached_directory_mtime: Option<&Timestamp>,
         is_at_repo_root: bool,
     ) -> Result<bool, DirstateV2ParseError> {
         if self.can_skip_fs_readdir(directory_metadata, cached_directory_mtime)
         {
             dirstate_nodes
                 .par_iter()
                 .map(|dirstate_node| {
                     let fs_path = directory_fs_path.join(get_path_from_bytes(
                         dirstate_node.base_name(self.dmap.on_disk)?.as_bytes(),
                     ));
                     match std::fs::symlink_metadata(&fs_path) {
                         Ok(fs_metadata) => self.traverse_fs_and_dirstate(
                             &fs_path,
                             &fs_metadata,
                             dirstate_node,
                             has_ignored_ancestor,
                         ),
                         Err(e) if e.kind() == std::io::ErrorKind::NotFound => {
                             self.traverse_dirstate_only(dirstate_node)
                         }
                         Err(error) => {
                             let hg_path =
                                 dirstate_node.full_path(self.dmap.on_disk)?;
                             Ok(self.io_error(error, hg_path))
                         }
                     }
                 })
                 .collect::<Result<_, _>>()?;
 
-            // Conservatively don’t let the caller assume that there aren’t
-            // any, since we don’t know.
-            let directory_has_any_fs_only_entry = true;
+            // We don’t know, so conservatively say this isn’t the case
+            let children_all_have_dirstate_node_or_are_ignored = false;
 
-            return Ok(directory_has_any_fs_only_entry);
+            return Ok(children_all_have_dirstate_node_or_are_ignored);
         }
 
         let mut fs_entries = if let Ok(entries) = self.read_dir(
             directory_hg_path,
             directory_fs_path,
             is_at_repo_root,
         ) {
             entries
         } else {
             // Treat an unreadable directory (typically because of insufficient
             // permissions) like an empty directory. `self.read_dir` has
             // already called `self.io_error` so a warning will be emitted.
             Vec::new()
         };
 
         // `merge_join_by` requires both its input iterators to be sorted:
 
         let dirstate_nodes = dirstate_nodes.sorted();
         // `sort_unstable_by_key` doesn’t allow keys borrowing from the value:
         // https://github.com/rust-lang/rust/issues/34162
         fs_entries.sort_unstable_by(|e1, e2| e1.base_name.cmp(&e2.base_name));
 
         // Propagate here any error that would happen inside the comparison
         // callback below
         for dirstate_node in &dirstate_nodes {
             dirstate_node.base_name(self.dmap.on_disk)?;
         }
         itertools::merge_join_by(
             dirstate_nodes,
             &fs_entries,
             |dirstate_node, fs_entry| {
                 // This `unwrap` never panics because we already propagated
                 // those errors above
                 dirstate_node
                     .base_name(self.dmap.on_disk)
                     .unwrap()
                     .cmp(&fs_entry.base_name)
             },
         )
         .par_bridge()
         .map(|pair| {
             use itertools::EitherOrBoth::*;
-            let is_fs_only = pair.is_right();
+            let has_dirstate_node_or_is_ignored;
             match pair {
-                Both(dirstate_node, fs_entry) => self
-                    .traverse_fs_and_dirstate(
+                Both(dirstate_node, fs_entry) => {
+                    self.traverse_fs_and_dirstate(
                         &fs_entry.full_path,
                         &fs_entry.metadata,
                         dirstate_node,
                         has_ignored_ancestor,
-                    )?,
+                    )?;
+                    has_dirstate_node_or_is_ignored = true
+                }
                 Left(dirstate_node) => {
-                    self.traverse_dirstate_only(dirstate_node)?
+                    self.traverse_dirstate_only(dirstate_node)?;
+                    has_dirstate_node_or_is_ignored = true;
                 }
-                Right(fs_entry) => self.traverse_fs_only(
-                    has_ignored_ancestor,
-                    directory_hg_path,
-                    fs_entry,
-                ),
+                Right(fs_entry) => {
+                    has_dirstate_node_or_is_ignored = self.traverse_fs_only(
+                        has_ignored_ancestor,
+                        directory_hg_path,
+                        fs_entry,
+                    )
+                }
             }
-            Ok(is_fs_only)
+            Ok(has_dirstate_node_or_is_ignored)
         })
-        .try_reduce(|| false, |a, b| Ok(a || b))
+        .try_reduce(|| true, |a, b| Ok(a && b))
     }
 
     fn traverse_fs_and_dirstate(
         &self,
         fs_path: &Path,
         fs_metadata: &std::fs::Metadata,
         dirstate_node: NodeRef<'tree, 'on_disk>,
         has_ignored_ancestor: bool,
     ) -> Result<(), DirstateV2ParseError> {
         self.check_for_outdated_directory_cache(&dirstate_node)?;
         let hg_path = &dirstate_node.full_path_borrowed(self.dmap.on_disk)?;
         let file_type = fs_metadata.file_type();
         let file_or_symlink = file_type.is_file() || file_type.is_symlink();
         if !file_or_symlink {
             // If we previously had a file here, it was removed (with
             // `hg rm` or similar) or deleted before it could be
             // replaced by a directory or something else.
             self.mark_removed_or_deleted_if_file(
                 &hg_path,
                 dirstate_node.state()?,
             );
         }
         if file_type.is_dir() {
             if self.options.collect_traversed_dirs {
                 self.outcome
                     .lock()
                     .unwrap()
                     .traversed
                     .push(hg_path.detach_from_tree())
             }
             let is_ignored = has_ignored_ancestor || (self.ignore_fn)(hg_path);
             let is_at_repo_root = false;
-            let directory_has_any_fs_only_entry = self
+            let children_all_have_dirstate_node_or_are_ignored = self
                 .traverse_fs_directory_and_dirstate(
                     is_ignored,
                     dirstate_node.children(self.dmap.on_disk)?,
                     hg_path,
                     fs_path,
                     Some(fs_metadata),
                     dirstate_node.cached_directory_mtime(),
                     is_at_repo_root,
                 )?;
             self.maybe_save_directory_mtime(
-                directory_has_any_fs_only_entry,
+                children_all_have_dirstate_node_or_are_ignored,
                 fs_metadata,
                 dirstate_node,
             )?
         } else {
             if file_or_symlink && self.matcher.matches(hg_path) {
                 if let Some(state) = dirstate_node.state()? {
                     match state {
                         EntryState::Added => self
                             .outcome
                             .lock()
                             .unwrap()
                             .added
                             .push(hg_path.detach_from_tree()),
                         EntryState::Removed => self
                             .outcome
                             .lock()
                             .unwrap()
                             .removed
                             .push(hg_path.detach_from_tree()),
                         EntryState::Merged => self
                             .outcome
                             .lock()
                             .unwrap()
                             .modified
                             .push(hg_path.detach_from_tree()),
                         EntryState::Normal => self
                             .handle_normal_file(&dirstate_node, fs_metadata)?,
                         // This variant is not used in DirstateMap
                         // nodes
                         EntryState::Unknown => unreachable!(),
                     }
                 } else {
                     // `node.entry.is_none()` indicates a "directory"
                     // node, but the filesystem has a file
-                    self.mark_unknown_or_ignored(has_ignored_ancestor, hg_path)
+                    self.mark_unknown_or_ignored(
+                        has_ignored_ancestor,
+                        hg_path,
+                    );
                 }
             }
 
             for child_node in dirstate_node.children(self.dmap.on_disk)?.iter()
             {
                 self.traverse_dirstate_only(child_node)?
             }
         }
         Ok(())
     }
 
     fn maybe_save_directory_mtime(
         &self,
-        directory_has_any_fs_only_entry: bool,
+        children_all_have_dirstate_node_or_are_ignored: bool,
         directory_metadata: &std::fs::Metadata,
         dirstate_node: NodeRef<'tree, 'on_disk>,
     ) -> Result<(), DirstateV2ParseError> {
-        if !directory_has_any_fs_only_entry {
+        if children_all_have_dirstate_node_or_are_ignored {
             // All filesystem directory entries from `read_dir` have a
             // corresponding node in the dirstate, so we can reconstitute the
             // names of those entries without calling `read_dir` again.
             if let (Some(status_start), Ok(directory_mtime)) = (
                 &self.filesystem_time_at_status_start,
                 directory_metadata.modified(),
             ) {
                 // Although the Rust standard library’s `SystemTime` type
                 // has nanosecond precision, the times reported for a
                 // directory’s (or file’s) modified time may have lower
                 // resolution based on the filesystem (for example ext3
                 // only stores integer seconds), kernel (see
                 // https://stackoverflow.com/a/14393315/1162888), etc.
                 if &directory_mtime >= status_start {
                     // The directory was modified too recently, don’t cache its
                     // `read_dir` results.
                     //
                     // A timeline like this is possible:
                     //
                     // 1. A change to this directory (direct child was
                     //    added or removed) cause its mtime to be set
                     //    (possibly truncated) to `directory_mtime`
                     // 2. This `status` algorithm calls `read_dir`
                     // 3. An other change is made to the same directory is
                     //    made so that calling `read_dir` agin would give
                     //    different results, but soon enough after 1. that
                     //    the mtime stays the same
                     //
                     // On a system where the time resolution poor, this
                     // scenario is not unlikely if all three steps are caused
                     // by the same script.
                 } else {
                     // We’ve observed (through `status_start`) that time has
                     // “progressed” since `directory_mtime`, so any further
                     // change to this directory is extremely likely to cause a
                     // different mtime.
                     //
                     // Having the same mtime again is not entirely impossible
                     // since the system clock is not monotonous. It could jump
                     // backward to some point before `directory_mtime`, then a
                     // directory change could potentially happen during exactly
                     // the wrong tick.
                     //
                     // We deem this scenario (unlike the previous one) to be
                     // unlikely enough in practice.
                     let timestamp = directory_mtime.into();
                     let cached = dirstate_node.cached_directory_mtime();
                     if cached != Some(&timestamp) {
                         let hg_path = dirstate_node
                             .full_path_borrowed(self.dmap.on_disk)?
                             .detach_from_tree();
                         self.new_cachable_directories
                             .lock()
                             .unwrap()
                             .push((hg_path, timestamp))
                     }
                 }
             }
         }
         Ok(())
     }
 
     /// A file with `EntryState::Normal` in the dirstate was found in the
     /// filesystem
     fn handle_normal_file(
         &self,
         dirstate_node: &NodeRef<'tree, 'on_disk>,
         fs_metadata: &std::fs::Metadata,
     ) -> Result<(), DirstateV2ParseError> {
         // Keep the low 31 bits
         fn truncate_u64(value: u64) -> i32 {
             (value & 0x7FFF_FFFF) as i32
         }
         fn truncate_i64(value: i64) -> i32 {
             (value & 0x7FFF_FFFF) as i32
         }
 
         let entry = dirstate_node
             .entry()?
             .expect("handle_normal_file called with entry-less node");
         let hg_path = &dirstate_node.full_path_borrowed(self.dmap.on_disk)?;
         let mode_changed =
             || self.options.check_exec && entry.mode_changed(fs_metadata);
         let size_changed = entry.size != truncate_u64(fs_metadata.len());
         if entry.size >= 0
             && size_changed
             && fs_metadata.file_type().is_symlink()
         {
             // issue6456: Size returned may be longer due to encryption
             // on EXT-4 fscrypt. TODO maybe only do it on EXT4?
             self.outcome
                 .lock()
                 .unwrap()
                 .unsure
                 .push(hg_path.detach_from_tree())
         } else if dirstate_node.has_copy_source()
             || entry.is_from_other_parent()
             || (entry.size >= 0 && (size_changed || mode_changed()))
         {
             self.outcome
                 .lock()
                 .unwrap()
                 .modified
                 .push(hg_path.detach_from_tree())
         } else {
             let mtime = mtime_seconds(fs_metadata);
             if truncate_i64(mtime) != entry.mtime
                 || mtime == self.options.last_normal_time
             {
                 self.outcome
                     .lock()
                     .unwrap()
                     .unsure
                     .push(hg_path.detach_from_tree())
             } else if self.options.list_clean {
                 self.outcome
                     .lock()
                     .unwrap()
                     .clean
                     .push(hg_path.detach_from_tree())
             }
         }
         Ok(())
     }
 
     /// A node in the dirstate tree has no corresponding filesystem entry
     fn traverse_dirstate_only(
         &self,
         dirstate_node: NodeRef<'tree, 'on_disk>,
     ) -> Result<(), DirstateV2ParseError> {
         self.check_for_outdated_directory_cache(&dirstate_node)?;
         self.mark_removed_or_deleted_if_file(
             &dirstate_node.full_path_borrowed(self.dmap.on_disk)?,
             dirstate_node.state()?,
         );
         dirstate_node
             .children(self.dmap.on_disk)?
             .par_iter()
             .map(|child_node| self.traverse_dirstate_only(child_node))
             .collect()
     }
 
     /// A node in the dirstate tree has no corresponding *file* on the
     /// filesystem
     ///
     /// Does nothing on a "directory" node
     fn mark_removed_or_deleted_if_file(
         &self,
         hg_path: &BorrowedPath<'tree, 'on_disk>,
         dirstate_node_state: Option<EntryState>,
     ) {
         if let Some(state) = dirstate_node_state {
             if self.matcher.matches(hg_path) {
                 if let EntryState::Removed = state {
                     self.outcome
                         .lock()
                         .unwrap()
                         .removed
                         .push(hg_path.detach_from_tree())
                 } else {
                     self.outcome
                         .lock()
                         .unwrap()
                         .deleted
                         .push(hg_path.detach_from_tree())
                 }
             }
         }
     }
 
     /// Something in the filesystem has no corresponding dirstate node
+    ///
+    /// Returns whether that path is ignored
     fn traverse_fs_only(
         &self,
         has_ignored_ancestor: bool,
         directory_hg_path: &HgPath,
         fs_entry: &DirEntry,
-    ) {
+    ) -> bool {
         let hg_path = directory_hg_path.join(&fs_entry.base_name);
         let file_type = fs_entry.metadata.file_type();
         let file_or_symlink = file_type.is_file() || file_type.is_symlink();
         if file_type.is_dir() {
             let is_ignored =
                 has_ignored_ancestor || (self.ignore_fn)(&hg_path);
             let traverse_children = if is_ignored {
                 // Descendants of an ignored directory are all ignored
                 self.options.list_ignored
             } else {
                 // Descendants of an unknown directory may be either unknown or
                 // ignored
                 self.options.list_unknown || self.options.list_ignored
             };
             if traverse_children {
                 let is_at_repo_root = false;
                 if let Ok(children_fs_entries) = self.read_dir(
                     &hg_path,
                     &fs_entry.full_path,
                     is_at_repo_root,
                 ) {
                     children_fs_entries.par_iter().for_each(|child_fs_entry| {
                         self.traverse_fs_only(
                             is_ignored,
                             &hg_path,
                             child_fs_entry,
-                        )
+                        );
                     })
                 }
             }
             if self.options.collect_traversed_dirs {
                 self.outcome.lock().unwrap().traversed.push(hg_path.into())
             }
-        } else if file_or_symlink && self.matcher.matches(&hg_path) {
-            self.mark_unknown_or_ignored(
-                has_ignored_ancestor,
-                &BorrowedPath::InMemory(&hg_path),
-            )
+            is_ignored
+        } else {
+            if file_or_symlink {
+                if self.matcher.matches(&hg_path) {
+                    self.mark_unknown_or_ignored(
+                        has_ignored_ancestor,
+                        &BorrowedPath::InMemory(&hg_path),
+                    )
+                } else {
+                    // We haven’t computed whether this path is ignored. It
+                    // might not be, and a future run of status might have a
+                    // different matcher that matches it. So treat it as not
+                    // ignored. That is, inhibit readdir caching of the parent
+                    // directory.
+                    false
+                }
+            } else {
+                // This is neither a directory, a plain file, or a symlink.
+                // Treat it like an ignored file.
+                true
+            }
         }
     }
 
+    /// Returns whether that path is ignored
     fn mark_unknown_or_ignored(
         &self,
         has_ignored_ancestor: bool,
         hg_path: &BorrowedPath<'_, 'on_disk>,
-    ) {
+    ) -> bool {
         let is_ignored = has_ignored_ancestor || (self.ignore_fn)(&hg_path);
         if is_ignored {
             if self.options.list_ignored {
                 self.outcome
                     .lock()
                     .unwrap()
                     .ignored
                     .push(hg_path.detach_from_tree())
             }
         } else {
             if self.options.list_unknown {
                 self.outcome
                     .lock()
                     .unwrap()
                     .unknown
                     .push(hg_path.detach_from_tree())
             }
         }
+        is_ignored
     }
 }
 
 #[cfg(unix)] // TODO
 fn mtime_seconds(metadata: &std::fs::Metadata) -> i64 {
     // Going through `Metadata::modified()` would be portable, but would take
     // care to construct a `SystemTime` value with sub-second precision just
     // for us to throw that away here.
     use std::os::unix::fs::MetadataExt;
     metadata.mtime()
 }
 
 struct DirEntry {
     base_name: HgPathBuf,
     full_path: PathBuf,
     metadata: std::fs::Metadata,
 }
 
 impl DirEntry {
     /// Returns **unsorted** entries in the given directory, with name and
     /// metadata.
     ///
     /// If a `.hg` sub-directory is encountered:
     ///
     /// * At the repository root, ignore that sub-directory
     /// * Elsewhere, we’re listing the content of a sub-repo. Return an empty
     ///   list instead.
     fn read_dir(path: &Path, is_at_repo_root: bool) -> io::Result<Vec<Self>> {
         let mut results = Vec::new();
         for entry in path.read_dir()? {
             let entry = entry?;
             let metadata = entry.metadata()?;
             let name = get_bytes_from_os_string(entry.file_name());
             // FIXME don't do this when cached
             if name == b".hg" {
                 if is_at_repo_root {
                     // Skip the repo’s own .hg (might be a symlink)
                     continue;
                 } else if metadata.is_dir() {
                     // A .hg sub-directory at another location means a subrepo,
                     // skip it entirely.
                     return Ok(Vec::new());
                 }
             }
             results.push(DirEntry {
                 base_name: name.into(),
                 full_path: entry.path(),
                 metadata,
             })
         }
         Ok(results)
     }
 }
 
 /// Return the `mtime` of a temporary file newly-created in the `.hg` directory
 /// of the give repository.
 ///
 /// This is similar to `SystemTime::now()`, with the result truncated to the
 /// same time resolution as other files’ modification times. Using `.hg`
 /// instead of the system’s default temporary directory (such as `/tmp`) makes
 /// it more likely the temporary file is in the same disk partition as contents
 /// of the working directory, which can matter since different filesystems may
 /// store timestamps with different resolutions.
 ///
 /// This may fail, typically if we lack write permissions. In that case we
 /// should continue the `status()` algoritm anyway and consider the current
 /// date/time to be unknown.
 fn filesystem_now(repo_root: &Path) -> Result<SystemTime, io::Error> {
     tempfile::tempfile_in(repo_root.join(".hg"))?
         .metadata()?
         .modified()
 }