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Differential D10919

rust: Document the DirstateMapMethods trait
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Authored by SimonSapin on Jul 1 2021, 12:51 PM.

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pulkit
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rHG8851acad5906: rust: Document the DirstateMapMethods trait

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SimonSapin created this revision.Jul 1 2021, 12:51 PM
pulkit accepted this revision.Jul 3 2021, 7:37 AM
This revision is now accepted and ready to land.Jul 3 2021, 7:37 AM
SimonSapin added a commit: rHG8851acad5906: rust: Document the DirstateMapMethods trait.Jul 3 2021, 3:28 PM
Closed by commit rHG8851acad5906: rust: Document the DirstateMapMethods trait (authored by SimonSapin). · Explain Why
This revision was automatically updated to reflect the committed changes.

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Diff 28768

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

use crate::DirstateParents; use crate::DirstateParents;
use crate::DirstateStatus; use crate::DirstateStatus;
use crate::EntryState; use crate::EntryState;
use crate::PatternFileWarning; use crate::PatternFileWarning;
use crate::StateMapIter; use crate::StateMapIter;
use crate::StatusError; use crate::StatusError;
use crate::StatusOptions; use crate::StatusOptions;
/// `rust/hg-cpython/src/dirstate/dirstate_map.rs` implements in Rust a
/// `DirstateMap` Python class that wraps `Box<dyn DirstateMapMethods + Send>`,
/// a trait object of this trait. Except for constructors, this trait defines
/// all APIs that the class needs to interact with its inner dirstate map.
///
/// A trait object is used to support two different concrete types:
///
/// * `rust/hg-core/src/dirstate/dirstate_map.rs` defines the "flat dirstate
/// map" which is based on a few large `HgPath`-keyed `HashMap` and `HashSet`
/// fields.
/// * `rust/hg-core/src/dirstate_tree/dirstate_map.rs` defines the "tree
/// dirstate map" based on a tree data struture with nodes for directories
/// containing child nodes for their files and sub-directories. This tree
/// enables a more efficient algorithm for `hg status`, but its details are
/// abstracted in this trait.
///
/// The dirstate map associates paths of files in the working directory to
/// various information about the state of those files.
pub trait DirstateMapMethods { pub trait DirstateMapMethods {
/// Remove information about all files in this map
fn clear(&mut self); fn clear(&mut self);
/// Add or change the information associated to a given file.
///
/// `old_state` is the state in the entry that `get` would have returned
/// before this call, or `EntryState::Unknown` if there was no such entry.
///
/// `entry.state` should never be `EntryState::Unknown`.
fn add_file( fn add_file(
&mut self, &mut self,
filename: &HgPath, filename: &HgPath,
old_state: EntryState, old_state: EntryState,
entry: DirstateEntry, entry: DirstateEntry,
) -> Result<(), DirstateError>; ) -> Result<(), DirstateError>;
/// Mark a file as "removed" (as in `hg rm`).
///
/// `old_state` is the state in the entry that `get` would have returned
/// before this call, or `EntryState::Unknown` if there was no such entry.
///
/// `size` is not actually a size but the 0 or -1 or -2 value that would be
/// put in the size field in the dirstate-v1!format.
fn remove_file( fn remove_file(
&mut self, &mut self,
filename: &HgPath, filename: &HgPath,
old_state: EntryState, old_state: EntryState,
size: i32, size: i32,
) -> Result<(), DirstateError>; ) -> Result<(), DirstateError>;
/// Drop information about this file from the map if any, and return
/// whether there was any.
///
/// `get` will now return `None` for this filename.
///
/// `old_state` is the state in the entry that `get` would have returned
/// before this call, or `EntryState::Unknown` if there was no such entry.
fn drop_file( fn drop_file(
&mut self, &mut self,
filename: &HgPath, filename: &HgPath,
old_state: EntryState, old_state: EntryState,
) -> Result<bool, DirstateError>; ) -> Result<bool, DirstateError>;
/// Among given files, mark the stored `mtime` as ambiguous if there is one
/// (if `state == EntryState::Normal`) equal to the given current Unix
/// timestamp.
fn clear_ambiguous_times( fn clear_ambiguous_times(
&mut self, &mut self,
filenames: Vec<HgPathBuf>, filenames: Vec<HgPathBuf>,
now: i32, now: i32,
) -> Result<(), DirstateV2ParseError>; ) -> Result<(), DirstateV2ParseError>;
/// Return whether the map has an "non-normal" entry for the given
/// filename. That is, any entry with a `state` other than
/// `EntryState::Normal` or with an ambiguous `mtime`.
fn non_normal_entries_contains( fn non_normal_entries_contains(
&mut self, &mut self,
key: &HgPath, key: &HgPath,
) -> Result<bool, DirstateV2ParseError>; ) -> Result<bool, DirstateV2ParseError>;
/// Mark the given path as "normal" file. This is only relevant in the flat
/// dirstate map where there is a separate `HashSet` that needs to be kept
/// up to date.
fn non_normal_entries_remove(&mut self, key: &HgPath); fn non_normal_entries_remove(&mut self, key: &HgPath);
/// Return an iterator of paths whose respective entry are either
/// "non-normal" (see `non_normal_entries_contains`) or "from other
/// parent".
///
/// If that information is cached, create the cache as needed.
///
/// "From other parent" is defined as `state == Normal && size == -2`.
///
/// Because parse errors can happen during iteration, the iterated items
/// are `Result`s.
fn non_normal_or_other_parent_paths( fn non_normal_or_other_parent_paths(
&mut self, &mut self,
) -> Box<dyn Iterator<Item = Result<&HgPath, DirstateV2ParseError>> + '_>; ) -> Box<dyn Iterator<Item = Result<&HgPath, DirstateV2ParseError>> + '_>;
/// Create the cache for `non_normal_or_other_parent_paths` if needed.
///
/// If `force` is true, the cache is re-created even if it already exists.
fn set_non_normal_other_parent_entries(&mut self, force: bool); fn set_non_normal_other_parent_entries(&mut self, force: bool);
/// Return an iterator of paths whose respective entry are "non-normal"
/// (see `non_normal_entries_contains`).
///
/// If that information is cached, create the cache as needed.
///
/// Because parse errors can happen during iteration, the iterated items
/// are `Result`s.
fn iter_non_normal_paths( fn iter_non_normal_paths(
&mut self, &mut self,
) -> Box< ) -> Box<
dyn Iterator<Item = Result<&HgPath, DirstateV2ParseError>> + Send + '_, dyn Iterator<Item = Result<&HgPath, DirstateV2ParseError>> + Send + '_,
>; >;
/// Same as `iter_non_normal_paths`, but takes `&self` instead of `&mut
/// self`.
///
/// Panics if a cache is necessary but does not exist yet.
fn iter_non_normal_paths_panic( fn iter_non_normal_paths_panic(
&self, &self,
) -> Box< ) -> Box<
dyn Iterator<Item = Result<&HgPath, DirstateV2ParseError>> + Send + '_, dyn Iterator<Item = Result<&HgPath, DirstateV2ParseError>> + Send + '_,
>; >;
/// Return an iterator of paths whose respective entry are "from other
/// parent".
///
/// If that information is cached, create the cache as needed.
///
/// "From other parent" is defined as `state == Normal && size == -2`.
///
/// Because parse errors can happen during iteration, the iterated items
/// are `Result`s.
fn iter_other_parent_paths( fn iter_other_parent_paths(
&mut self, &mut self,
) -> Box< ) -> Box<
dyn Iterator<Item = Result<&HgPath, DirstateV2ParseError>> + Send + '_, dyn Iterator<Item = Result<&HgPath, DirstateV2ParseError>> + Send + '_,
>; >;
/// Returns whether the sub-tree rooted at the given directory contains any
/// tracked file.
///
/// A file is tracked if it has a `state` other than `EntryState::Removed`.
fn has_tracked_dir( fn has_tracked_dir(
&mut self, &mut self,
directory: &HgPath, directory: &HgPath,
) -> Result<bool, DirstateError>; ) -> Result<bool, DirstateError>;
/// Returns whether the sub-tree rooted at the given directory contains any
/// file with a dirstate entry.
fn has_dir(&mut self, directory: &HgPath) -> Result<bool, DirstateError>; fn has_dir(&mut self, directory: &HgPath) -> Result<bool, DirstateError>;
/// Clear mtimes that are ambigous with `now` (similar to
/// `clear_ambiguous_times` but for all files in the dirstate map), and
/// serialize bytes to write the `.hg/dirstate` file to disk in dirstate-v1
/// format.
fn pack_v1( fn pack_v1(
&mut self, &mut self,
parents: DirstateParents, parents: DirstateParents,
now: Timestamp, now: Timestamp,
) -> Result<Vec<u8>, DirstateError>; ) -> Result<Vec<u8>, DirstateError>;
/// Clear mtimes that are ambigous with `now` (similar to
/// `clear_ambiguous_times` but for all files in the dirstate map), and
/// serialize bytes to write the `.hg/dirstate` file to disk in dirstate-v2
/// format.
///
/// Note: this is only supported by the tree dirstate map.
fn pack_v2( fn pack_v2(
&mut self, &mut self,
parents: DirstateParents, parents: DirstateParents,
now: Timestamp, now: Timestamp,
) -> Result<Vec<u8>, DirstateError>; ) -> Result<Vec<u8>, DirstateError>;
/// Run the status algorithm.
///
/// This is not sematically a method of the dirstate map, but a different
/// algorithm is used for the flat v.s. tree dirstate map so having it in
/// this trait enables the same dynamic dispatch as with other methods.
fn status<'a>( fn status<'a>(
&'a mut self, &'a mut self,
matcher: &'a (dyn Matcher + Sync), matcher: &'a (dyn Matcher + Sync),
root_dir: PathBuf, root_dir: PathBuf,
ignore_files: Vec<PathBuf>, ignore_files: Vec<PathBuf>,
options: StatusOptions, options: StatusOptions,
) -> Result<(DirstateStatus<'a>, Vec<PatternFileWarning>), StatusError>; ) -> Result<(DirstateStatus<'a>, Vec<PatternFileWarning>), StatusError>;
/// Returns how many files in the dirstate map have a recorded copy source.
fn copy_map_len(&self) -> usize; fn copy_map_len(&self) -> usize;
/// Returns an iterator of `(path, copy_source)` for all files that have a
/// copy source.
fn copy_map_iter(&self) -> CopyMapIter<'_>; fn copy_map_iter(&self) -> CopyMapIter<'_>;
/// Returns whether the givef file has a copy source.
fn copy_map_contains_key( fn copy_map_contains_key(
&self, &self,
key: &HgPath, key: &HgPath,
) -> Result<bool, DirstateV2ParseError>; ) -> Result<bool, DirstateV2ParseError>;
/// Returns the copy source for the given file.
fn copy_map_get( fn copy_map_get(
&self, &self,
key: &HgPath, key: &HgPath,
) -> Result<Option<&HgPath>, DirstateV2ParseError>; ) -> Result<Option<&HgPath>, DirstateV2ParseError>;
/// Removes the recorded copy source if any for the given file, and returns
/// it.
fn copy_map_remove( fn copy_map_remove(
&mut self, &mut self,
key: &HgPath, key: &HgPath,
) -> Result<Option<HgPathBuf>, DirstateV2ParseError>; ) -> Result<Option<HgPathBuf>, DirstateV2ParseError>;
/// Set the given `value` copy source for the given `key` file.
fn copy_map_insert( fn copy_map_insert(
&mut self, &mut self,
key: HgPathBuf, key: HgPathBuf,
value: HgPathBuf, value: HgPathBuf,
) -> Result<Option<HgPathBuf>, DirstateV2ParseError>; ) -> Result<Option<HgPathBuf>, DirstateV2ParseError>;
/// Returns the number of files that have an entry.
fn len(&self) -> usize; fn len(&self) -> usize;
/// Returns whether the given file has an entry.
fn contains_key(&self, key: &HgPath) fn contains_key(&self, key: &HgPath)
-> Result<bool, DirstateV2ParseError>; -> Result<bool, DirstateV2ParseError>;
/// Returns the entry, if any, for the given file.
fn get( fn get(
&self, &self,
key: &HgPath, key: &HgPath,
) -> Result<Option<DirstateEntry>, DirstateV2ParseError>; ) -> Result<Option<DirstateEntry>, DirstateV2ParseError>;
/// Returns a `(path, entry)` iterator of files that have an entry.
///
/// Because parse errors can happen during iteration, the iterated items
/// are `Result`s.
fn iter(&self) -> StateMapIter<'_>; fn iter(&self) -> StateMapIter<'_>;
/// In the tree dirstate, return an iterator of "directory" (entry-less)
/// nodes with the data stored for them. This is for `hg debugdirstate
/// --dirs`.
///
/// In the flat dirstate, returns an empty iterator.
///
/// Because parse errors can happen during iteration, the iterated items
/// are `Result`s.
fn iter_directories( fn iter_directories(
&self, &self,
) -> Box< ) -> Box<
dyn Iterator< dyn Iterator<
Item = Result< Item = Result<
(&HgPath, Option<Timestamp>), (&HgPath, Option<Timestamp>),
DirstateV2ParseError, DirstateV2ParseError,
>, >,

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

/// In bytes from `self.full_path.start` /// In bytes from `self.full_path.start`
base_name_start: Size, base_name_start: Size,
copy_source: OptPathSlice, copy_source: OptPathSlice,
children: ChildNodes, children: ChildNodes,
pub(super) descendants_with_entry_count: Size, pub(super) descendants_with_entry_count: Size,
pub(super) tracked_descendants_count: Size, pub(super) tracked_descendants_count: Size,
/// Dependending on the value of `state`: /// Depending on the value of `state`:
/// ///
/// * A null byte: `data` is not used. /// * A null byte: `data` is not used.
/// ///
/// * A `n`, `a`, `r`, or `m` ASCII byte: `state` and `data` together /// * A `n`, `a`, `r`, or `m` ASCII byte: `state` and `data` together
/// represent a dirstate entry like in the v1 format. /// represent a dirstate entry like in the v1 format.
/// ///
/// * A `d` ASCII byte: the bytes of `data` should instead be interpreted /// * A `d` ASCII byte: the bytes of `data` should instead be interpreted
/// as the `Timestamp` for the mtime of a cached directory. /// as the `Timestamp` for the mtime of a cached directory.