extend file provider with read_bytes method and return cow

Cargo.toml

@@ -13,10 +13,11 @@ license = "MIT"
 # See more keys and their definitions at https://doc.rust-lang.org/cargo/reference/manifest.html
 
 [features]
-default = ["lua", "shulkerbox"]
+default = ["fs_access", "lua", "shulkerbox"]
+fs_access = ["shulkerbox?/fs_access"]
+lua = ["dep:mlua"]
 serde = ["dep:serde", "shulkerbox?/serde"]
 shulkerbox = ["dep:shulkerbox"]
-lua = ["dep:mlua"]
 
 [target.'cfg(target_arch = "wasm32")'.dependencies]
 path-absolutize = { version = "3.1.1", features = ["use_unix_paths_on_wasm"] }
@@ -31,7 +32,7 @@ itertools = "0.13.0"
 mlua = { version = "0.9.7", features = ["lua54", "vendored"], optional = true }
 path-absolutize = "3.1.1"
 serde = { version = "1.0.197", features = ["derive", "rc"], optional = true }
-shulkerbox = { git = "https://github.com/moritz-hoelting/shulkerbox", default-features = false, optional = true, rev = "a2d20dab8ea97bbd873edafb23afaad34292457f" }
+shulkerbox = { git = "https://github.com/moritz-hoelting/shulkerbox", default-features = false, optional = true, rev = "aff342a64a94981af942223345b5a5f105212957" }
 strsim = "0.11.1"
 strum = { version = "0.26.2", features = ["derive"] }
 strum_macros = "0.26.2"

src/base/error.rs

@@ -2,8 +2,10 @@
 #[allow(missing_docs)]
 #[derive(Debug, thiserror::Error)]
 pub enum Error {
-    #[error("An error occurred while working with Input/Output.")]
+    #[error("An error occurred while working with Input/Output: {0}")]
     IoError(String),
+    #[error(transparent)]
+    Utf8Error(#[from] std::str::Utf8Error),
     #[error("An error occurred while lexing the source code.")]
     LexicalError(#[from] crate::lexical::Error),
     #[error("An error occured while tokenizing the source code.")]

src/base/file_provider.rs

@@ -1,15 +1,30 @@
-use std::path::{Path, PathBuf};
+use std::{
+    borrow::Cow,
+    path::{Path, PathBuf},
+};
 
 use super::Error;
 
 /// A trait for providing file contents.
 pub trait FileProvider {
+    /// Reads the contents of the file at the given path as bytes.
+    ///
+    /// # Errors
+    /// - If an error occurs while reading the file.
+    /// - If the file does not exist.
+    fn read_bytes<P: AsRef<Path>>(&self, path: P) -> Result<Cow<[u8]>, Error>;
+
     /// Reads the contents of the file at the given path.
     ///
     /// # Errors
     /// - If an error occurs while reading the file.
     /// - If the file does not exist.
-    fn read_to_string<P: AsRef<Path>>(&self, path: P) -> Result<String, Error>;
+    /// - If the file is not valid UTF-8.
+    fn read_str<P: AsRef<Path>>(&self, path: P) -> Result<Cow<str>, Error> {
+        let bytes = self.read_bytes(path)?;
+        let string = std::str::from_utf8(&bytes)?.to_string();
+        Ok(Cow::Owned(string))
+    }
 }
 
 /// Provides file contents from the file system.
@@ -37,28 +52,54 @@ where
 }
 
 impl FileProvider for FsProvider {
-    fn read_to_string<P: AsRef<Path>>(&self, path: P) -> Result<String, Error> {
+    fn read_bytes<P: AsRef<Path>>(&self, path: P) -> Result<Cow<[u8]>, Error> {
         let full_path = self.root.join(path);
-        std::fs::read_to_string(full_path).map_err(|err| Error::IoError(err.to_string()))
+        std::fs::read(full_path)
+            .map(Cow::Owned)
+            .map_err(|err| Error::IoError(err.to_string()))
+    }
+
+    fn read_str<P: AsRef<Path>>(&self, path: P) -> Result<Cow<str>, Error> {
+        let full_path = self.root.join(path);
+        std::fs::read_to_string(full_path)
+            .map(Cow::Owned)
+            .map_err(|err| Error::IoError(err.to_string()))
     }
 }
 
 #[cfg(feature = "shulkerbox")]
 mod vfs {
+    use std::borrow::Cow;
+
     use super::{Error, FileProvider, Path};
     use shulkerbox::virtual_fs::{VFile, VFolder};
 
     impl FileProvider for VFolder {
-        fn read_to_string<P: AsRef<Path>>(&self, path: P) -> Result<String, Error> {
+        fn read_bytes<P: AsRef<Path>>(&self, path: P) -> Result<Cow<[u8]>, Error> {
+            normalize_path_str(path).map_or_else(
+                || Err(Error::IoError("Invalid path".to_string())),
+                |path| {
+                    self.get_file(&path)
+                        .ok_or_else(|| Error::IoError("File not found".to_string()))
+                        .map(|file| Cow::Borrowed(file.as_bytes()))
+                },
+            )
+        }
+
+        fn read_str<P: AsRef<Path>>(&self, path: P) -> Result<Cow<str>, Error> {
             normalize_path_str(path).map_or_else(
                 || Err(Error::IoError("Invalid path".to_string())),
                 |path| {
                     self.get_file(&path)
                         .ok_or_else(|| Error::IoError("File not found".to_string()))
                         .and_then(|file| match file {
-                            VFile::Text(text) => Ok(text.to_owned()),
+                            VFile::Text(text) => Ok(Cow::Borrowed(text.as_str())),
-                            VFile::Binary(bin) => String::from_utf8(bin.clone())
+                            VFile::Binary(bin) => {
-                                .map_err(|err| Error::IoError(err.to_string())),
+                                let string = std::str::from_utf8(bin)
+                                    .map_err(|err| Error::IoError(err.to_string()))?;
+
+                                Ok(Cow::Borrowed(string))
+                            }
                         })
                 },
             )
@@ -112,13 +153,16 @@ mod vfs {
             dir.add_file("foo.txt", VFile::Text("foo".to_string()));
             dir.add_file("bar/baz.txt", VFile::Text("bar, baz".to_string()));
 
-            assert_eq!(dir.read_to_string("foo.txt").unwrap(), "foo".to_string());
             assert_eq!(
-                dir.read_to_string("bar/baz.txt").unwrap(),
+                dir.read_str("foo.txt").unwrap().into_owned(),
+                "foo".to_string()
+            );
+            assert_eq!(
+                dir.read_str("bar/baz.txt").unwrap().into_owned(),
                 "bar, baz".to_string()
             );
             assert!(matches!(
-                dir.read_to_string("nonexistent.txt"),
+                dir.read_str("nonexistent.txt"),
                 Err(Error::IoError(_))
             ));
         }

src/base/source_file.rs

@@ -92,8 +92,12 @@ impl SourceFile {
         identifier: String,
         provider: &impl FileProvider,
     ) -> Result<Arc<Self>, Error> {
-        let source = provider.read_to_string(path)?;
+        let source = provider.read_str(path)?;
-        Ok(Self::new(path.to_path_buf(), identifier, source))
+        Ok(Self::new(
+            path.to_path_buf(),
+            identifier,
+            source.into_owned(),
+        ))
     }
 
     /// Get the [`Location`] of a given byte index

src/transpile/error.rs

@@ -51,10 +51,11 @@ impl MissingFunctionDeclaration {
         let alternatives = functions
             .iter()
             .filter_map(|((program_identifier, function_name), data)| {
-                let normalized_distance = strsim::normalized_levenshtein(own_name, function_name);
+                let normalized_distance =
+                    strsim::normalized_damerau_levenshtein(own_name, function_name);
                 (program_identifier == own_program_identifier
                     && (normalized_distance > 0.8
-                        || strsim::levenshtein(own_name, function_name) < 3))
+                        || strsim::damerau_levenshtein(own_name, function_name) < 3))
                     .then_some((normalized_distance, data))
             })
             .sorted_by(|a, b| a.0.partial_cmp(&b.0).unwrap_or(std::cmp::Ordering::Equal))