Fix rojo plugin install by adding Vfs::exists (#1169)

crates/memofs/CHANGELOG.md

@@ -1,11 +1,15 @@
 # memofs Changelog
 
 ## Unreleased Changes
+* Added `Vfs::exists`. [#1169]
+* Added `create_dir` and `create_dir_all` to allow creating directories. [#937]
+
+[#1169]: https://github.com/rojo-rbx/rojo/pull/1169
+[#937]: https://github.com/rojo-rbx/rojo/pull/937
 
 ## 0.3.0 (2024-03-15)
 * Changed `StdBackend` file watching component to use minimal recursive watches. [#830]
 * Added `Vfs::read_to_string` and `Vfs::read_to_string_lf_normalized` [#854]
-* Added `create_dir` and `create_dir_all` to allow creating directories.
 
 [#830]: https://github.com/rojo-rbx/rojo/pull/830
 [#854]: https://github.com/rojo-rbx/rojo/pull/854

crates/memofs/src/in_memory_fs.rs

@@ -157,6 +157,11 @@ impl VfsBackend for InMemoryFs {
         )
     }
 
+    fn exists(&mut self, path: &Path) -> io::Result<bool> {
+        let inner = self.inner.lock().unwrap();
+        Ok(inner.entries.contains_key(path))
+    }
+
     fn read_dir(&mut self, path: &Path) -> io::Result<ReadDir> {
         let inner = self.inner.lock().unwrap();
 

crates/memofs/src/lib.rs

@@ -70,6 +70,7 @@ impl<T> IoResultExt<T> for io::Result<T> {
 pub trait VfsBackend: sealed::Sealed + Send + 'static {
     fn read(&mut self, path: &Path) -> io::Result<Vec<u8>>;
     fn write(&mut self, path: &Path, data: &[u8]) -> io::Result<()>;
+    fn exists(&mut self, path: &Path) -> io::Result<bool>;
     fn read_dir(&mut self, path: &Path) -> io::Result<ReadDir>;
     fn create_dir(&mut self, path: &Path) -> io::Result<()>;
     fn create_dir_all(&mut self, path: &Path) -> io::Result<()>;
@@ -175,6 +176,11 @@ impl VfsInner {
         Ok(Arc::new(contents_str.into()))
     }
 
+    fn exists<P: AsRef<Path>>(&mut self, path: P) -> io::Result<bool> {
+        let path = path.as_ref();
+        self.backend.exists(path)
+    }
+
     fn write<P: AsRef<Path>, C: AsRef<[u8]>>(&mut self, path: P, contents: C) -> io::Result<()> {
         let path = path.as_ref();
         let contents = contents.as_ref();
@@ -338,6 +344,17 @@ impl Vfs {
         self.inner.lock().unwrap().read_dir(path)
     }
 
+    /// Return whether the given path exists.
+    ///
+    /// Roughly equivalent to [`std::fs::exists`][std::fs::exists].
+    ///
+    /// [std::fs::exists]: https://doc.rust-lang.org/stable/std/fs/fn.exists.html
+    #[inline]
+    pub fn exists<P: AsRef<Path>>(&self, path: P) -> io::Result<bool> {
+        let path = path.as_ref();
+        self.inner.lock().unwrap().exists(path)
+    }
+
     /// Creates a directory at the provided location.
     ///
     /// Roughly equivalent to [`std::fs::create_dir`][std::fs::create_dir].

crates/memofs/src/noop_backend.rs

@@ -22,6 +22,10 @@ impl VfsBackend for NoopBackend {
         Err(io::Error::other("NoopBackend doesn't do anything"))
     }
 
+    fn exists(&mut self, _path: &Path) -> io::Result<bool> {
+        Err(io::Error::other("NoopBackend doesn't do anything"))
+    }
+
     fn read_dir(&mut self, _path: &Path) -> io::Result<ReadDir> {
         Err(io::Error::other("NoopBackend doesn't do anything"))
     }

crates/memofs/src/std_backend.rs

@@ -63,6 +63,10 @@ impl VfsBackend for StdBackend {
         fs_err::write(path, data)
     }
 
+    fn exists(&mut self, path: &Path) -> io::Result<bool> {
+        std::fs::exists(path)
+    }
+
     fn read_dir(&mut self, path: &Path) -> io::Result<ReadDir> {
         let entries: Result<Vec<_>, _> = fs_err::read_dir(path)?.collect();
         let mut entries = entries?;