diff --git a/rust/hg-core/src/repo.rs b/rust/hg-core/src/repo.rs --- a/rust/hg-core/src/repo.rs +++ b/rust/hg-core/src/repo.rs @@ -29,11 +29,11 @@ store: PathBuf, requirements: HashSet, config: Config, - dirstate_parents: LazyCell, - dirstate_data_file_uuid: LazyCell>, HgError>, - dirstate_map: LazyCell, - changelog: LazyCell, - manifestlog: LazyCell, + dirstate_parents: LazyCell, + dirstate_data_file_uuid: LazyCell>>, + dirstate_map: LazyCell, + changelog: LazyCell, + manifestlog: LazyCell, } #[derive(Debug, derive_more::From)] @@ -182,13 +182,11 @@ store: store_path, dot_hg, config: repo_config, - dirstate_parents: LazyCell::new(Self::read_dirstate_parents), - dirstate_data_file_uuid: LazyCell::new( - Self::read_dirstate_data_file_uuid, - ), - dirstate_map: LazyCell::new(Self::new_dirstate_map), - changelog: LazyCell::new(Self::new_changelog), - manifestlog: LazyCell::new(Self::new_manifestlog), + dirstate_parents: LazyCell::new(), + dirstate_data_file_uuid: LazyCell::new(), + dirstate_map: LazyCell::new(), + changelog: LazyCell::new(), + manifestlog: LazyCell::new(), }; requirements::check(&repo)?; @@ -260,7 +258,9 @@ } pub fn dirstate_parents(&self) -> Result { - Ok(*self.dirstate_parents.get_or_init(self)?) + Ok(*self + .dirstate_parents + .get_or_init(|| self.read_dirstate_parents())?) } fn read_dirstate_parents(&self) -> Result { @@ -340,13 +340,14 @@ pub fn dirstate_map( &self, ) -> Result, DirstateError> { - self.dirstate_map.get_or_init(self) + self.dirstate_map.get_or_init(|| self.new_dirstate_map()) } pub fn dirstate_map_mut( &self, ) -> Result, DirstateError> { - self.dirstate_map.get_mut_or_init(self) + self.dirstate_map + .get_mut_or_init(|| self.new_dirstate_map()) } fn new_changelog(&self) -> Result { @@ -354,11 +355,11 @@ } pub fn changelog(&self) -> Result, HgError> { - self.changelog.get_or_init(self) + self.changelog.get_or_init(|| self.new_changelog()) } pub fn changelog_mut(&self) -> Result, HgError> { - self.changelog.get_mut_or_init(self) + self.changelog.get_mut_or_init(|| self.new_changelog()) } fn new_manifestlog(&self) -> Result { @@ -366,11 +367,11 @@ } pub fn manifestlog(&self) -> Result, HgError> { - self.manifestlog.get_or_init(self) + self.manifestlog.get_or_init(|| self.new_manifestlog()) } pub fn manifestlog_mut(&self) -> Result, HgError> { - self.manifestlog.get_mut_or_init(self) + self.manifestlog.get_mut_or_init(|| self.new_manifestlog()) } /// Returns the manifest of the *changeset* with the given node ID @@ -424,7 +425,7 @@ // it’s unset let parents = self.dirstate_parents()?; let (packed_dirstate, old_uuid_to_remove) = if self.has_dirstate_v2() { - let uuid_opt = self.dirstate_data_file_uuid.get_or_init(self)?; + let uuid_opt = self.dirstate_data_file_uuid.get_or_init(|| self.read_dirstate_data_file_uuid())?; let uuid_opt = uuid_opt.as_ref(); let can_append = uuid_opt.is_some(); let (data, tree_metadata, append, old_data_size) = @@ -508,19 +509,17 @@ /// Lazily-initialized component of `Repo` with interior mutability /// /// This differs from `OnceCell` in that the value can still be "deinitialized" -/// later by setting its inner `Option` to `None`. -struct LazyCell { +/// later by setting its inner `Option` to `None`. It also takes the +/// initialization function as an argument when the value is requested, not +/// when the instance is created. +struct LazyCell { value: RefCell>, - // `Fn`s that don’t capture environment are zero-size, so this box does - // not allocate: - init: Box Result>, } -impl LazyCell { - fn new(init: impl Fn(&Repo) -> Result + 'static) -> Self { +impl LazyCell { + fn new() -> Self { Self { value: RefCell::new(None), - init: Box::new(init), } } @@ -528,23 +527,29 @@ *self.value.borrow_mut() = Some(value) } - fn get_or_init(&self, repo: &Repo) -> Result, E> { + fn get_or_init( + &self, + init: impl Fn() -> Result, + ) -> Result, E> { let mut borrowed = self.value.borrow(); if borrowed.is_none() { drop(borrowed); // Only use `borrow_mut` if it is really needed to avoid panic in // case there is another outstanding borrow but mutation is not // needed. - *self.value.borrow_mut() = Some((self.init)(repo)?); + *self.value.borrow_mut() = Some(init()?); borrowed = self.value.borrow() } Ok(Ref::map(borrowed, |option| option.as_ref().unwrap())) } - fn get_mut_or_init(&self, repo: &Repo) -> Result, E> { + fn get_mut_or_init( + &self, + init: impl Fn() -> Result, + ) -> Result, E> { let mut borrowed = self.value.borrow_mut(); if borrowed.is_none() { - *borrowed = Some((self.init)(repo)?); + *borrowed = Some(init()?); } Ok(RefMut::map(borrowed, |option| option.as_mut().unwrap())) }