( )⚙ D12531 rust-dirstatemap: add simpler version of `get_node_mut`

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Differential D12531

rust-dirstatemap: add simpler version of `get_node_mut`
Needs ReviewPublic

Authored by Alphare on Tue, Apr 12, 12:05 PM.

Details

Reviewers
None
Group Reviewers
hg-reviewers
Summary

This will help reduce code and footgun potential for simpler callers.

Diff Detail

Repository
rHG Mercurial
Branch
default
Lint
No Linters Available
Unit
No Unit Test Coverage

Revision Contents
Changeset List

Diff 33094

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

} else { } else {
return Ok(None); return Ok(None);
} }
} }
} }
/// Returns a mutable reference to the node at `path` if it exists /// Returns a mutable reference to the node at `path` if it exists
/// ///
/// `each_ancestor` is a callback that is called for each ancestor node
/// when descending the tree. It is used to keep the different counters
/// of the `DirstateMap` up-to-date.
fn get_node_mut<'tree>(
&'tree mut self,
path: &HgPath,
each_ancestor: impl FnMut(&mut Node),
) -> Result<Option<&'tree mut Node<'on_disk>>, DirstateV2ParseError> {
Self::get_node_mut_inner(
self.on_disk,
&mut self.unreachable_bytes,
&mut self.root,
path,
each_ancestor,
)
}
/// Lower-level version of `get_node_mut`.
///
/// This takes `root` instead of `&mut self` so that callers can mutate /// This takes `root` instead of `&mut self` so that callers can mutate
/// other fields while the returned borrow is still valid. /// other fields while the returned borrow is still valid.
/// ///
/// `each_ancestor` is a callback that is called for each ancestor node /// `each_ancestor` is a callback that is called for each ancestor node
/// when descending the tree. It is used to keep the different counters /// when descending the tree. It is used to keep the different counters
/// of the `DirstateMap` up-to-date. /// of the `DirstateMap` up-to-date.
fn get_node_mut<'tree>( fn get_node_mut_inner<'tree>(
on_disk: &'on_disk [u8], on_disk: &'on_disk [u8],
unreachable_bytes: &mut u32, unreachable_bytes: &mut u32,
root: &'tree mut ChildNodes<'on_disk>, root: &'tree mut ChildNodes<'on_disk>,
path: &HgPath, path: &HgPath,
mut each_ancestor: impl FnMut(&mut Node), mut each_ancestor: impl FnMut(&mut Node),
) -> Result<Option<&'tree mut Node<'on_disk>>, DirstateV2ParseError> { ) -> Result<Option<&'tree mut Node<'on_disk>>, DirstateV2ParseError> {
let mut children = root; let mut children = root;
let mut components = path.components(); let mut components = path.components();
/// # Panics /// # Panics
/// ///
/// Panics if the node does not exist. /// Panics if the node does not exist.
fn set_untracked( fn set_untracked(
&mut self, &mut self,
filename: &HgPath, filename: &HgPath,
old_entry: DirstateEntry, old_entry: DirstateEntry,
) -> Result<(), DirstateV2ParseError> { ) -> Result<(), DirstateV2ParseError> {
let node = DirstateMap::get_node_mut( let node = self
self.on_disk, .get_node_mut(filename, |ancestor| {
&mut self.unreachable_bytes,
&mut self.root,
filename,
|ancestor| {
ancestor.tracked_descendants_count = ancestor ancestor.tracked_descendants_count = ancestor
.tracked_descendants_count .tracked_descendants_count
.checked_sub(1) .checked_sub(1)
.expect("tracked_descendants_count should be >= 0"); .expect("tracked_descendants_count should be >= 0");
}, })?
)?
.expect("node should exist"); .expect("node should exist");
let mut new_entry = old_entry.clone(); let mut new_entry = old_entry.clone();
new_entry.set_untracked(); new_entry.set_untracked();
node.data = NodeData::Entry(new_entry); node.data = NodeData::Entry(new_entry);
Ok(()) Ok(())
} }
/// Set a node as clean in the dirstate. /// Set a node as clean in the dirstate.
/// ///
/// It is the responsibility of the caller to remove the copy source. /// It is the responsibility of the caller to remove the copy source.
/// ///
/// # Panics /// # Panics
/// ///
/// Panics if the node does not exist. /// Panics if the node does not exist.
fn set_clean( fn set_clean(
&mut self, &mut self,
filename: &HgPath, filename: &HgPath,
old_entry: DirstateEntry, old_entry: DirstateEntry,
mode: u32, mode: u32,
size: u32, size: u32,
mtime: TruncatedTimestamp, mtime: TruncatedTimestamp,
) -> Result<(), DirstateError> { ) -> Result<(), DirstateError> {
let node = DirstateMap::get_node_mut( let node = self
self.on_disk, .get_node_mut(filename, |ancestor| {
&mut self.unreachable_bytes,
&mut self.root,
filename,
|ancestor| {
if !old_entry.tracked() { if !old_entry.tracked() {
ancestor.tracked_descendants_count += 1; ancestor.tracked_descendants_count += 1;
} }
}, })?
)?
.expect("node should exist"); .expect("node should exist");
let mut new_entry = old_entry.clone(); let mut new_entry = old_entry.clone();
new_entry.set_clean(mode, size, mtime); new_entry.set_clean(mode, size, mtime);
node.data = NodeData::Entry(new_entry); node.data = NodeData::Entry(new_entry);
Ok(()) Ok(())
} }
/// Set a node as possibly dirty in the dirstate. /// Set a node as possibly dirty in the dirstate.
/// ///
/// # Panics /// # Panics
/// ///
/// Panics if the node does not exist. /// Panics if the node does not exist.
fn set_possibly_dirty( fn set_possibly_dirty(
&mut self, &mut self,
filename: &HgPath, filename: &HgPath,
) -> Result<(), DirstateError> { ) -> Result<(), DirstateError> {
let node = DirstateMap::get_node_mut( let node = self
self.on_disk, .get_node_mut(filename, |_ancestor| {})?
&mut self.unreachable_bytes,
&mut self.root,
filename,
|_ancestor| {},
)?
.expect("node should exist"); .expect("node should exist");
let entry = node.data.as_entry_mut().expect("entry should exist"); let entry = node.data.as_entry_mut().expect("entry should exist");
entry.set_possibly_dirty(); entry.set_possibly_dirty();
node.data = NodeData::Entry(*entry); node.data = NodeData::Entry(*entry);
Ok(()) Ok(())
} }
/// Clears the cached mtime for the (potential) folder at `path`. /// Clears the cached mtime for the (potential) folder at `path`.
pub(super) fn clear_cached_mtime( pub(super) fn clear_cached_mtime(
&mut self, &mut self,
path: &HgPath, path: &HgPath,
) -> Result<(), DirstateV2ParseError> { ) -> Result<(), DirstateV2ParseError> {
let node = match DirstateMap::get_node_mut( let node = match self.get_node_mut(path, |_ancestor| {})? {
self.on_disk,
&mut self.unreachable_bytes,
&mut self.root,
path,
|_ancestor| {},
)? {
Some(node) => node, Some(node) => node,
None => return Ok(()), None => return Ok(()),
}; };
if let NodeData::CachedDirectory { .. } = &node.data { if let NodeData::CachedDirectory { .. } = &node.data {
node.data = NodeData::None node.data = NodeData::None
} }
Ok(()) Ok(())
} }
/// Sets the cached mtime for the (potential) folder at `path`. /// Sets the cached mtime for the (potential) folder at `path`.
pub(super) fn set_cached_mtime( pub(super) fn set_cached_mtime(
&mut self, &mut self,
path: &HgPath, path: &HgPath,
mtime: TruncatedTimestamp, mtime: TruncatedTimestamp,
) -> Result<(), DirstateV2ParseError> { ) -> Result<(), DirstateV2ParseError> {
let node = match DirstateMap::get_node_mut( let node = match self.get_node_mut(path, |_ancestor| {})? {
self.on_disk,
&mut self.unreachable_bytes,
&mut self.root,
path,
|_ancestor| {},
)? {
Some(node) => node, Some(node) => node,
None => return Ok(()), None => return Ok(()),
}; };
match &node.data { match &node.data {
NodeData::Entry(_) => {} // Don’t overwrite an entry NodeData::Entry(_) => {} // Don’t overwrite an entry
NodeData::CachedDirectory { .. } | NodeData::None => { NodeData::CachedDirectory { .. } | NodeData::None => {
node.data = NodeData::CachedDirectory { mtime } node.data = NodeData::CachedDirectory { mtime }
} }
pub fn copy_map_remove( pub fn copy_map_remove(
&mut self, &mut self,
key: &HgPath, key: &HgPath,
) -> Result<Option<HgPathBuf>, DirstateV2ParseError> { ) -> Result<Option<HgPathBuf>, DirstateV2ParseError> {
self.with_dmap_mut(|map| { self.with_dmap_mut(|map| {
let count = &mut map.nodes_with_copy_source_count; let count = &mut map.nodes_with_copy_source_count;
let unreachable_bytes = &mut map.unreachable_bytes; let unreachable_bytes = &mut map.unreachable_bytes;
Ok(DirstateMap::get_node_mut( Ok(DirstateMap::get_node_mut_inner(
map.on_disk, map.on_disk,
unreachable_bytes, unreachable_bytes,
&mut map.root, &mut map.root,
key, key,
|_ancestor| {}, |_ancestor| {},
)? )?
.and_then(|node| { .and_then(|node| {
if let Some(source) = &node.copy_source { if let Some(source) = &node.copy_source {