bendns' repos / rust-analyzer
Unnamed repository; edit this file 'description' to name the repository.
Diffstat (limited to 'crates/vfs/src/lib.rs')
-rw-r--r--crates/vfs/src/lib.rs110
1 files changed, 52 insertions, 58 deletions
diff --git a/crates/vfs/src/lib.rs b/crates/vfs/src/lib.rs
index ef5b10ee9d..34a85818eb 100644
--- a/crates/vfs/src/lib.rs
+++ b/crates/vfs/src/lib.rs
@@ -1,8 +1,8 @@
//! # Virtual File System
//!
-//! VFS stores all files read by rust-analyzer. Reading file contents from VFS
-//! always returns the same contents, unless VFS was explicitly modified with
-//! [`set_file_contents`]. All changes to VFS are logged, and can be retrieved via
+//! VFS records all file changes pushed to it via [`set_file_contents`].
+//! As such it only ever stores changes, not the actual content of a file at any given moment.
+//! All file changes are logged, and can be retrieved via
//! [`take_changes`] method. The pack of changes is then pushed to `salsa` and
//! triggers incremental recomputation.
//!
@@ -84,40 +84,65 @@ impl FileId {
/// safe because `FileId` is a newtype of `u32`
impl nohash_hasher::IsEnabled for FileId {}
-/// Storage for all files read by rust-analyzer.
+/// Storage for all file changes and the file id to path mapping.
///
/// For more information see the [crate-level](crate) documentation.
#[derive(Default)]
pub struct Vfs {
interner: PathInterner,
- data: Vec<Option<Vec<u8>>>,
+ data: Vec<FileState>,
changes: Vec<ChangedFile>,
}
+#[derive(Copy, PartialEq, PartialOrd, Clone)]
+pub enum FileState {
+ Exists,
+ Deleted,
+}
+
/// Changed file in the [`Vfs`].
#[derive(Debug)]
pub struct ChangedFile {
/// Id of the changed file
pub file_id: FileId,
/// Kind of change
- pub change_kind: ChangeKind,
+ pub change: Change,
}
impl ChangedFile {
/// Returns `true` if the change is not [`Delete`](ChangeKind::Delete).
pub fn exists(&self) -> bool {
- self.change_kind != ChangeKind::Delete
+ !matches!(self.change, Change::Delete)
}
/// Returns `true` if the change is [`Create`](ChangeKind::Create) or
- /// [`Delete`](ChangeKind::Delete).
+ /// [`Delete`](Change::Delete).
pub fn is_created_or_deleted(&self) -> bool {
- matches!(self.change_kind, ChangeKind::Create | ChangeKind::Delete)
+ matches!(self.change, Change::Create(_) | Change::Delete)
}
+
+ pub fn kind(&self) -> ChangeKind {
+ match self.change {
+ Change::Create(_) => ChangeKind::Create,
+ Change::Modify(_) => ChangeKind::Modify,
+ Change::Delete => ChangeKind::Delete,
+ }
+ }
+}
+
+/// Kind of [file change](ChangedFile).
+#[derive(Eq, PartialEq, Debug)]
+pub enum Change {
+ /// The file was (re-)created
+ Create(Vec<u8>),
+ /// The file was modified
+ Modify(Vec<u8>),
+ /// The file was deleted
+ Delete,
}
/// Kind of [file change](ChangedFile).
-#[derive(Eq, PartialEq, Copy, Clone, Debug)]
+#[derive(Eq, PartialEq, Debug)]
pub enum ChangeKind {
/// The file was (re-)created
Create,
@@ -130,7 +155,7 @@ pub enum ChangeKind {
impl Vfs {
/// Id of the given path if it exists in the `Vfs` and is not deleted.
pub fn file_id(&self, path: &VfsPath) -> Option<FileId> {
- self.interner.get(path).filter(|&it| self.get(it).is_some())
+ self.interner.get(path).filter(|&it| matches!(self.get(it), FileState::Exists))
}
/// File path corresponding to the given `file_id`.
@@ -142,28 +167,13 @@ impl Vfs {
self.interner.lookup(file_id).clone()
}
- /// File content corresponding to the given `file_id`.
- ///
- /// # Panics
- ///
- /// Panics if the id is not present in the `Vfs`, or if the corresponding file is
- /// deleted.
- pub fn file_contents(&self, file_id: FileId) -> &[u8] {
- self.get(file_id).as_deref().unwrap()
- }
-
- /// Returns the overall memory usage for the stored files.
- pub fn memory_usage(&self) -> usize {
- self.data.iter().flatten().map(|d| d.capacity()).sum()
- }
-
/// Returns an iterator over the stored ids and their corresponding paths.
///
/// This will skip deleted files.
pub fn iter(&self) -> impl Iterator<Item = (FileId, &VfsPath)> + '_ {
(0..self.data.len())
.map(|it| FileId(it as u32))
- .filter(move |&file_id| self.get(file_id).is_some())
+ .filter(move |&file_id| matches!(self.get(file_id), FileState::Exists))
.map(move |file_id| {
let path = self.interner.lookup(file_id);
(file_id, path)
@@ -176,28 +186,21 @@ impl Vfs {
///
/// If the path does not currently exists in the `Vfs`, allocates a new
/// [`FileId`] for it.
- pub fn set_file_contents(&mut self, path: VfsPath, mut contents: Option<Vec<u8>>) -> bool {
+ pub fn set_file_contents(&mut self, path: VfsPath, contents: Option<Vec<u8>>) -> bool {
let file_id = self.alloc_file_id(path);
- let change_kind = match (self.get(file_id), &contents) {
- (None, None) => return false,
- (Some(old), Some(new)) if old == new => return false,
- (None, Some(_)) => ChangeKind::Create,
- (Some(_), None) => ChangeKind::Delete,
- (Some(_), Some(_)) => ChangeKind::Modify,
+ let change_kind = match (self.get(file_id), contents) {
+ (FileState::Deleted, None) => return false,
+ (FileState::Deleted, Some(v)) => Change::Create(v),
+ (FileState::Exists, None) => Change::Delete,
+ (FileState::Exists, Some(v)) => Change::Modify(v),
};
- if let Some(contents) = &mut contents {
- contents.shrink_to_fit();
- }
- *self.get_mut(file_id) = contents;
- self.changes.push(ChangedFile { file_id, change_kind });
+ let changed_file = ChangedFile { file_id, change: change_kind };
+ self.data[file_id.0 as usize] =
+ if changed_file.exists() { FileState::Exists } else { FileState::Deleted };
+ self.changes.push(changed_file);
true
}
- /// Returns `true` if the `Vfs` contains [changes](ChangedFile).
- pub fn has_changes(&self) -> bool {
- !self.changes.is_empty()
- }
-
/// Drain and returns all the changes in the `Vfs`.
pub fn take_changes(&mut self) -> Vec<ChangedFile> {
mem::take(&mut self.changes)
@@ -205,7 +208,7 @@ impl Vfs {
/// Provides a panic-less way to verify file_id validity.
pub fn exists(&self, file_id: FileId) -> bool {
- self.get(file_id).is_some()
+ matches!(self.get(file_id), FileState::Exists)
}
/// Returns the id associated with `path`
@@ -219,26 +222,17 @@ impl Vfs {
let file_id = self.interner.intern(path);
let idx = file_id.0 as usize;
let len = self.data.len().max(idx + 1);
- self.data.resize_with(len, || None);
+ self.data.resize(len, FileState::Deleted);
file_id
}
- /// Returns the content associated with the given `file_id`.
- ///
- /// # Panics
- ///
- /// Panics if no file is associated to that id.
- fn get(&self, file_id: FileId) -> &Option<Vec<u8>> {
- &self.data[file_id.0 as usize]
- }
-
- /// Mutably returns the content associated with the given `file_id`.
+ /// Returns the status of the file associated with the given `file_id`.
///
/// # Panics
///
/// Panics if no file is associated to that id.
- fn get_mut(&mut self, file_id: FileId) -> &mut Option<Vec<u8>> {
- &mut self.data[file_id.0 as usize]
+ fn get(&self, file_id: FileId) -> FileState {
+ self.data[file_id.0 as usize]
}
}