tinymist_vfs/
overlay.rs

1use std::{borrow::Borrow, marker::PhantomData, num::NonZeroU16, path::Path};
2
3use rpds::RedBlackTreeMapSync;
4use tinymist_std::ImmutPath;
5use typst::diag::FileResult;
6
7use crate::{AccessModel, Bytes, FileId, FileSnapshot, PathAccessModel};
8
9pub(crate) type RawFileId = NonZeroU16;
10
11/// Provides overlay access model which allows to shadow the underlying access
12/// model with memory contents.
13#[derive(Default, Debug, Clone)]
14pub struct OverlayAccessModel<K, M, S = K>
15where
16    S: Ord,
17{
18    files: RedBlackTreeMapSync<S, FileSnapshot>,
19    /// The underlying access model
20    pub inner: M,
21    _key: PhantomData<fn() -> K>,
22}
23
24impl<K, M, S> OverlayAccessModel<K, M, S>
25where
26    S: Ord,
27{
28    /// Create a new [`OverlayAccessModel`] with the given inner access model
29    pub fn new(inner: M) -> Self {
30        Self {
31            files: RedBlackTreeMapSync::default(),
32            inner,
33            _key: PhantomData,
34        }
35    }
36
37    /// Get the inner access model
38    pub fn inner(&self) -> &M {
39        &self.inner
40    }
41
42    /// Get the mutable reference to the inner access model
43    pub fn inner_mut(&mut self) -> &mut M {
44        &mut self.inner
45    }
46
47    /// Clear the shadowed files
48    pub fn clear_shadow(&mut self) {
49        self.files = RedBlackTreeMapSync::default();
50    }
51}
52
53impl<M> OverlayAccessModel<ImmutPath, M> {
54    /// Get the shadowed file paths
55    pub fn file_paths(&self) -> Vec<ImmutPath> {
56        self.files.keys().cloned().collect()
57    }
58
59    /// Add a shadow file to the [`OverlayAccessModel`]
60    pub fn add_file<Q: Ord + ?Sized>(
61        &mut self,
62        path: &Q,
63        snap: FileSnapshot,
64        cast: impl Fn(&Q) -> ImmutPath,
65    ) where
66        ImmutPath: Borrow<Q>,
67    {
68        match self.files.get_mut(path) {
69            Some(e) => {
70                *e = snap;
71            }
72            None => {
73                self.files.insert_mut(cast(path), snap);
74            }
75        }
76    }
77
78    /// Remove a shadow file from the [`OverlayAccessModel`]
79    pub fn remove_file<Q: Ord + ?Sized>(&mut self, path: &Q)
80    where
81        ImmutPath: Borrow<Q>,
82    {
83        self.files.remove_mut(path);
84    }
85}
86
87impl<M> OverlayAccessModel<FileId, M, RawFileId> {
88    /// Get the shadowed file ids
89    pub fn file_paths(&self) -> Vec<FileId> {
90        self.files.keys().copied().map(FileId::from_raw).collect()
91    }
92
93    /// Add a shadow file to the [`OverlayAccessModel`]
94    pub fn add_file(&mut self, id: &FileId, snap: FileSnapshot, cast: impl Fn(&FileId) -> FileId) {
95        match self.files.get_mut(&id.into_raw()) {
96            Some(e) => {
97                *e = snap;
98            }
99            None => {
100                self.files.insert_mut(cast(id).into_raw(), snap);
101            }
102        }
103    }
104
105    /// Remove a shadow file from the [`OverlayAccessModel`]
106    pub fn remove_file(&mut self, id: &FileId) {
107        self.files.remove_mut(&id.into_raw());
108    }
109}
110
111impl<M: PathAccessModel> PathAccessModel for OverlayAccessModel<ImmutPath, M> {
112    fn content(&self, src: &Path) -> FileResult<Bytes> {
113        if let Some(content) = self.files.get(src) {
114            return content.content().cloned();
115        }
116
117        self.inner.content(src)
118    }
119}
120
121impl<M: AccessModel> AccessModel for OverlayAccessModel<FileId, M, RawFileId> {
122    fn reset(&mut self) {
123        self.inner.reset();
124    }
125
126    fn content(&self, src: FileId) -> (Option<ImmutPath>, FileResult<Bytes>) {
127        if let Some(content) = self.files.get(&src.into_raw()) {
128            return (None, content.content().cloned());
129        }
130
131        self.inner.content(src)
132    }
133}
tinymist_vfs/overlay.rs

tinymist_vfs/
overlay.rs
