Update require implementation to satisfy Luau 0.700

Cargo.toml

@@ -2,7 +2,7 @@
 name = "mlua"
 version = "0.11.4" # remember to update mlua_derive
 authors = ["Aleksandr Orlenko <zxteam@pm.me>", "kyren <catherine@kyju.org>"]
-rust-version = "1.79.0"
+rust-version = "1.80.0"
 edition = "2021"
 repository = "https://github.com/mlua-rs/mlua"
 documentation = "https://docs.rs/mlua"
@@ -62,7 +62,7 @@ parking_lot = { version = "0.12", features = ["arc_lock"] }
 anyhow = { version = "1.0", optional = true }
 rustversion = "1.0"
 
-ffi = { package = "mlua-sys", version = "0.8.3", path = "mlua-sys" }
+ffi = { package = "mlua-sys", version = "0.9.0", path = "mlua-sys" }
 
 [dev-dependencies]
 trybuild = "1.0"

src/luau/require.rs

@@ -1,12 +1,10 @@
 use std::cell::RefCell;
-use std::collections::VecDeque;
 use std::ffi::CStr;
 use std::io::Result as IoResult;
 use std::ops::{Deref, DerefMut};
 use std::os::raw::{c_char, c_int, c_void};
-use std::path::{Component, Path, PathBuf};
 use std::result::Result as StdResult;
-use std::{env, fmt, fs, mem, ptr};
+use std::{fmt, mem, ptr};
 
 use crate::error::{Error, Result};
 use crate::function::Function;
@@ -14,6 +12,9 @@ use crate::state::{callback_error_ext, Lua};
 use crate::table::Table;
 use crate::types::MaybeSend;
 
+// TODO: Rename to FsRequirer
+pub use fs::TextRequirer;
+
 /// An error that can occur during navigation in the Luau `require-by-string` system.
 #[cfg(any(feature = "luau", doc))]
 #[cfg_attr(docsrs, doc(cfg(feature = "luau")))]
@@ -50,6 +51,9 @@ impl From<Error> for NavigateError {
 #[cfg(feature = "luau")]
 type WriteResult = ffi::luarequire_WriteResult;
 
+#[cfg(feature = "luau")]
+type ConfigStatus = ffi::luarequire_ConfigStatus;
+
 /// A trait for handling modules loading and navigation in the Luau `require-by-string` system.
 #[cfg(any(feature = "luau", doc))]
 #[cfg_attr(docsrs, doc(cfg(feature = "luau")))]
@@ -73,7 +77,7 @@ pub trait Require {
     /// Navigate to the given child directory.
     fn to_child(&mut self, name: &str) -> StdResult<(), NavigateError>;
 
-    /// Returns whether the context is currently pointing at a module
+    /// Returns whether the context is currently pointing at a module.
     fn has_module(&self) -> bool;
 
     /// Provides a cache key representing the current module.
@@ -103,226 +107,31 @@ impl fmt::Debug for dyn Require {
     }
 }
 
-/// The standard implementation of Luau `require-by-string` navigation.
-#[derive(Default, Debug)]
-pub struct TextRequirer {
-    /// An absolute path to the current Luau module (not mapped to a physical file)
-    abs_path: PathBuf,
-    /// A relative path to the current Luau module (not mapped to a physical file)
-    rel_path: PathBuf,
-    /// A physical path to the current Luau module, which is a file or a directory with an
-    /// `init.lua(u)` file
-    resolved_path: Option<PathBuf>,
+struct Context {
+    require: Box<dyn Require>,
+    config_cache: Option<IoResult<Vec<u8>>>,
 }
 
-impl TextRequirer {
-    /// The prefix used for chunk names in the require system.
-    /// Only chunk names starting with this prefix are allowed to be used in `require`.
-    const CHUNK_PREFIX: &str = "@";
-
-    /// The file extensions that are considered valid for Luau modules.
-    const FILE_EXTENSIONS: &[&str] = &["luau", "lua"];
-
-    /// Creates a new `TextRequirer` instance.
-    pub fn new() -> Self {
-        Self::default()
-    }
-
-    fn normalize_chunk_name(chunk_name: &str) -> &str {
-        if let Some((path, line)) = chunk_name.rsplit_once(':') {
-            if line.parse::<u32>().is_ok() {
-                return path;
-            }
-        }
-        chunk_name
-    }
-
-    // Normalizes the path by removing unnecessary components
-    fn normalize_path(path: &Path) -> PathBuf {
-        let mut components = VecDeque::new();
-
-        for comp in path.components() {
-            match comp {
-                Component::Prefix(..) | Component::RootDir => {
-                    components.push_back(comp);
-                }
-                Component::CurDir => {}
-                Component::ParentDir => {
-                    if matches!(components.back(), None | Some(Component::ParentDir)) {
-                        components.push_back(Component::ParentDir);
-                    } else if matches!(components.back(), Some(Component::Normal(..))) {
-                        components.pop_back();
-                    }
-                }
-                Component::Normal(..) => components.push_back(comp),
-            }
-        }
-
-        if matches!(components.front(), None | Some(Component::Normal(..))) {
-            components.push_front(Component::CurDir);
-        }
-
-        // Join the components back together
-        components.into_iter().collect()
-    }
-
-    /// Resolve a Luau module path to a physical file or directory.
-    ///
-    /// Empty directories without init files are considered valid as "intermediate" directories.
-    fn resolve_module(path: &Path) -> StdResult<Option<PathBuf>, NavigateError> {
-        let mut found_path = None;
-
-        if path.components().next_back() != Some(Component::Normal("init".as_ref())) {
-            let current_ext = (path.extension().and_then(|s| s.to_str()))
-                .map(|s| format!("{s}."))
-                .unwrap_or_default();
-            for ext in Self::FILE_EXTENSIONS {
-                let candidate = path.with_extension(format!("{current_ext}{ext}"));
-                if candidate.is_file() && found_path.replace(candidate).is_some() {
-                    return Err(NavigateError::Ambiguous);
-                }
-            }
-        }
-        if path.is_dir() {
-            for component in Self::FILE_EXTENSIONS.iter().map(|ext| format!("init.{ext}")) {
-                let candidate = path.join(component);
-                if candidate.is_file() && found_path.replace(candidate).is_some() {
-                    return Err(NavigateError::Ambiguous);
-                }
-            }
-
-            if found_path.is_none() {
-                // Directories without init files are considered valid "intermediate" path
-                return Ok(None);
-            }
-        }
-
-        Ok(Some(found_path.ok_or(NavigateError::NotFound)?))
-    }
-}
-
-impl Require for TextRequirer {
-    fn is_require_allowed(&self, chunk_name: &str) -> bool {
-        chunk_name.starts_with(Self::CHUNK_PREFIX)
-    }
-
-    fn reset(&mut self, chunk_name: &str) -> StdResult<(), NavigateError> {
-        if !chunk_name.starts_with(Self::CHUNK_PREFIX) {
-            return Err(NavigateError::NotFound);
-        }
-        let chunk_name = Self::normalize_chunk_name(&chunk_name[1..]);
-        let chunk_path = Self::normalize_path(chunk_name.as_ref());
-
-        if chunk_path.extension() == Some("rs".as_ref()) {
-            // Special case for Rust source files, reset to the current directory
-            let chunk_filename = chunk_path.file_name().unwrap();
-            let cwd = env::current_dir().map_err(|_| NavigateError::NotFound)?;
-            self.abs_path = Self::normalize_path(&cwd.join(chunk_filename));
-            self.rel_path = ([Component::CurDir, Component::Normal(chunk_filename)].into_iter()).collect();
-            self.resolved_path = None;
-
-            return Ok(());
-        }
-
-        if chunk_path.is_absolute() {
-            let resolved_path = Self::resolve_module(&chunk_path)?;
-            self.abs_path = chunk_path.clone();
-            self.rel_path = chunk_path;
-            self.resolved_path = resolved_path;
-        } else {
-            // Relative path
-            let cwd = env::current_dir().map_err(|_| NavigateError::NotFound)?;
-            let abs_path = Self::normalize_path(&cwd.join(&chunk_path));
-            let resolved_path = Self::resolve_module(&abs_path)?;
-            self.abs_path = abs_path;
-            self.rel_path = chunk_path;
-            self.resolved_path = resolved_path;
-        }
-
-        Ok(())
-    }
-
-    fn jump_to_alias(&mut self, path: &str) -> StdResult<(), NavigateError> {
-        let path = Self::normalize_path(path.as_ref());
-        let resolved_path = Self::resolve_module(&path)?;
-
-        self.abs_path = path.clone();
-        self.rel_path = path;
-        self.resolved_path = resolved_path;
-
-        Ok(())
-    }
-
-    fn to_parent(&mut self) -> StdResult<(), NavigateError> {
-        let mut abs_path = self.abs_path.clone();
-        if !abs_path.pop() {
-            // It's important to return `NotFound` if we reached the root, as it's a "recoverable" error if we
-            // cannot go beyond the root directory.
-            // Luau "require-by-string` has a special logic to search for config file to resolve aliases.
-            return Err(NavigateError::NotFound);
-        }
-        let mut rel_parent = self.rel_path.clone();
-        rel_parent.pop();
-        let resolved_path = Self::resolve_module(&abs_path)?;
-
-        self.abs_path = abs_path;
-        self.rel_path = Self::normalize_path(&rel_parent);
-        self.resolved_path = resolved_path;
-
-        Ok(())
-    }
-
-    fn to_child(&mut self, name: &str) -> StdResult<(), NavigateError> {
-        let abs_path = self.abs_path.join(name);
-        let rel_path = self.rel_path.join(name);
-        let resolved_path = Self::resolve_module(&abs_path)?;
-
-        self.abs_path = abs_path;
-        self.rel_path = rel_path;
-        self.resolved_path = resolved_path;
-
-        Ok(())
-    }
-
-    fn has_module(&self) -> bool {
-        (self.resolved_path.as_deref())
-            .map(Path::is_file)
-            .unwrap_or(false)
-    }
-
-    fn cache_key(&self) -> String {
-        self.resolved_path.as_deref().unwrap().display().to_string()
-    }
-
-    fn has_config(&self) -> bool {
-        self.abs_path.is_dir() && self.abs_path.join(".luaurc").is_file()
-    }
-
-    fn config(&self) -> IoResult<Vec<u8>> {
-        fs::read(self.abs_path.join(".luaurc"))
-    }
-
-    fn loader(&self, lua: &Lua) -> Result<Function> {
-        let name = format!("@{}", self.rel_path.display());
-        lua.load(self.resolved_path.as_deref().unwrap())
-            .set_name(name)
-            .into_function()
-    }
-}
-
-struct Context(Box<dyn Require>);
-
 impl Deref for Context {
     type Target = dyn Require;
 
     fn deref(&self) -> &Self::Target {
-        &*self.0
+        &*self.require
     }
 }
 
 impl DerefMut for Context {
     fn deref_mut(&mut self) -> &mut Self::Target {
-        &mut *self.0
+        &mut *self.require
+    }
+}
+
+impl Context {
+    fn new(require: impl Require + MaybeSend + 'static) -> Self {
+        Context {
+            require: Box::new(require),
+            config_cache: None,
+        }
     }
 }
 
@@ -447,9 +256,18 @@ pub(super) unsafe extern "C-unwind" fn init_config(config: *mut ffi::luarequire_
         write_to_buffer(buffer, buffer_size, size_out, cache_key.as_bytes())
     }
 
-    unsafe extern "C-unwind" fn is_config_present(state: *mut ffi::lua_State, ctx: *mut c_void) -> bool {
-        let this = try_borrow!(state, ctx);
-        this.has_config()
+    unsafe extern "C-unwind" fn get_config_status(
+        state: *mut ffi::lua_State,
+        ctx: *mut c_void,
+    ) -> ConfigStatus {
+        let mut this = try_borrow_mut!(state, ctx);
+        if this.has_config() {
+            this.config_cache = Some(this.config());
+            if let Some(Ok(data)) = &this.config_cache {
+                return detect_config_format(data);
+            }
+        }
+        ConfigStatus::Absent
     }
 
     unsafe extern "C-unwind" fn get_config(
@@ -459,8 +277,10 @@ pub(super) unsafe extern "C-unwind" fn init_config(config: *mut ffi::luarequire_
         buffer_size: usize,
         size_out: *mut usize,
     ) -> WriteResult {
-        let this = try_borrow!(state, ctx);
-        let config = callback_error_ext(state, ptr::null_mut(), true, move |_, _| Ok(this.config()?));
+        let mut this = try_borrow_mut!(state, ctx);
+        let config = callback_error_ext(state, ptr::null_mut(), true, move |_, _| {
+            Ok(this.config_cache.take().unwrap_or_else(|| this.config())?)
+        });
         write_to_buffer(buffer, buffer_size, size_out, &config)
     }
 
@@ -489,12 +309,24 @@ pub(super) unsafe extern "C-unwind" fn init_config(config: *mut ffi::luarequire_
     (*config).get_chunkname = get_chunkname;
     (*config).get_loadname = get_loadname;
     (*config).get_cache_key = get_cache_key;
-    (*config).is_config_present = is_config_present;
+    (*config).get_config_status = get_config_status;
     (*config).get_alias = None;
     (*config).get_config = Some(get_config);
     (*config).load = load;
 }
 
+/// Detect configuration file format (JSON or Luau)
+fn detect_config_format(data: &[u8]) -> ConfigStatus {
+    let data = data.trim_ascii();
+    if data.starts_with(b"{") {
+        let data = &data[1..].trim_ascii_start();
+        if data.starts_with(b"\"") || data == b"}" {
+            return ConfigStatus::PresentJson;
+        }
+    }
+    ConfigStatus::PresentLuau
+}
+
 /// Helper function to write data to a buffer
 #[cfg(feature = "luau")]
 unsafe fn write_to_buffer(
@@ -545,7 +377,7 @@ pub(super) fn create_require_function<R: Require + MaybeSend + 'static>(
 
     let (get_cache_key, find_current_file, proxyrequire, registered_modules, loader_cache) = unsafe {
         lua.exec_raw::<(Function, Function, Function, Table, Table)>((), move |state| {
-            let context = Context(Box::new(require));
+            let context = Context::new(require);
             let context_ptr = ffi::lua_newuserdata_t(state, RefCell::new(context));
             ffi::lua_pushcclosured(state, get_cache_key, cstr!("get_cache_key"), 1);
             ffi::lua_pushcfunctiond(state, find_current_file, cstr!("find_current_file"));
@@ -637,52 +469,4 @@ pub(super) fn create_require_function<R: Require + MaybeSend + 'static>(
     .into_function()
 }
 
-#[cfg(test)]
-mod tests {
-    use std::path::Path;
-
-    use super::TextRequirer;
-
-    #[test]
-    fn test_path_normalize() {
-        for (input, expected) in [
-            // Basic formatting checks
-            ("", "./"),
-            (".", "./"),
-            ("a/relative/path", "./a/relative/path"),
-            // Paths containing extraneous '.' and '/' symbols
-            ("./remove/extraneous/symbols/", "./remove/extraneous/symbols"),
-            ("./remove/extraneous//symbols", "./remove/extraneous/symbols"),
-            ("./remove/extraneous/symbols/.", "./remove/extraneous/symbols"),
-            ("./remove/extraneous/./symbols", "./remove/extraneous/symbols"),
-            ("../remove/extraneous/symbols/", "../remove/extraneous/symbols"),
-            ("../remove/extraneous//symbols", "../remove/extraneous/symbols"),
-            ("../remove/extraneous/symbols/.", "../remove/extraneous/symbols"),
-            ("../remove/extraneous/./symbols", "../remove/extraneous/symbols"),
-            ("/remove/extraneous/symbols/", "/remove/extraneous/symbols"),
-            ("/remove/extraneous//symbols", "/remove/extraneous/symbols"),
-            ("/remove/extraneous/symbols/.", "/remove/extraneous/symbols"),
-            ("/remove/extraneous/./symbols", "/remove/extraneous/symbols"),
-            // Paths containing '..'
-            ("./remove/me/..", "./remove"),
-            ("./remove/me/../", "./remove"),
-            ("../remove/me/..", "../remove"),
-            ("../remove/me/../", "../remove"),
-            ("/remove/me/..", "/remove"),
-            ("/remove/me/../", "/remove"),
-            ("./..", "../"),
-            ("./../", "../"),
-            ("../..", "../../"),
-            ("../../", "../../"),
-            // '..' disappears if path is absolute and component is non-erasable
-            ("/../", "/"),
-        ] {
-            let path = TextRequirer::normalize_path(input.as_ref());
-            assert_eq!(
-                &path,
-                expected.as_ref() as &Path,
-                "wrong normalization for {input}"
-            );
-        }
-    }
-}
+mod fs;

src/luau/require/fs.rs

@@ -0,0 +1,278 @@
+use std::collections::VecDeque;
+use std::io::Result as IoResult;
+use std::path::{Component, Path, PathBuf};
+use std::result::Result as StdResult;
+use std::{env, fs};
+
+use crate::error::Result;
+use crate::function::Function;
+use crate::state::Lua;
+
+use super::{NavigateError, Require};
+
+/// The standard implementation of Luau `require-by-string` navigation.
+#[derive(Default, Debug)]
+pub struct TextRequirer {
+    /// An absolute path to the current Luau module (not mapped to a physical file)
+    abs_path: PathBuf,
+    /// A relative path to the current Luau module (not mapped to a physical file)
+    rel_path: PathBuf,
+    /// A physical path to the current Luau module, which is a file or a directory with an
+    /// `init.lua(u)` file
+    resolved_path: Option<PathBuf>,
+}
+
+impl TextRequirer {
+    /// The prefix used for chunk names in the require system.
+    /// Only chunk names starting with this prefix are allowed to be used in `require`.
+    const CHUNK_PREFIX: &str = "@";
+
+    /// The file extensions that are considered valid for Luau modules.
+    const FILE_EXTENSIONS: &[&str] = &["luau", "lua"];
+
+    /// The filename for the JSON configuration file.
+    const LUAURC_CONFIG_FILENAME: &str = ".luaurc";
+
+    /// The filename for the Luau configuration file.
+    const LUAU_CONFIG_FILENAME: &str = ".config.luau";
+
+    /// Creates a new `TextRequirer` instance.
+    pub fn new() -> Self {
+        Self::default()
+    }
+
+    fn normalize_chunk_name(chunk_name: &str) -> &str {
+        if let Some((path, line)) = chunk_name.rsplit_once(':') {
+            if line.parse::<u32>().is_ok() {
+                return path;
+            }
+        }
+        chunk_name
+    }
+
+    // Normalizes the path by removing unnecessary components
+    fn normalize_path(path: &Path) -> PathBuf {
+        let mut components = VecDeque::new();
+
+        for comp in path.components() {
+            match comp {
+                Component::Prefix(..) | Component::RootDir => {
+                    components.push_back(comp);
+                }
+                Component::CurDir => {}
+                Component::ParentDir => {
+                    if matches!(components.back(), None | Some(Component::ParentDir)) {
+                        components.push_back(Component::ParentDir);
+                    } else if matches!(components.back(), Some(Component::Normal(..))) {
+                        components.pop_back();
+                    }
+                }
+                Component::Normal(..) => components.push_back(comp),
+            }
+        }
+
+        if matches!(components.front(), None | Some(Component::Normal(..))) {
+            components.push_front(Component::CurDir);
+        }
+
+        // Join the components back together
+        components.into_iter().collect()
+    }
+
+    /// Resolve a Luau module path to a physical file or directory.
+    ///
+    /// Empty directories without init files are considered valid as "intermediate" directories.
+    fn resolve_module(path: &Path) -> StdResult<Option<PathBuf>, NavigateError> {
+        let mut found_path = None;
+
+        if path.components().next_back() != Some(Component::Normal("init".as_ref())) {
+            let current_ext = (path.extension().and_then(|s| s.to_str()))
+                .map(|s| format!("{s}."))
+                .unwrap_or_default();
+            for ext in Self::FILE_EXTENSIONS {
+                let candidate = path.with_extension(format!("{current_ext}{ext}"));
+                if candidate.is_file() && found_path.replace(candidate).is_some() {
+                    return Err(NavigateError::Ambiguous);
+                }
+            }
+        }
+        if path.is_dir() {
+            for component in Self::FILE_EXTENSIONS.iter().map(|ext| format!("init.{ext}")) {
+                let candidate = path.join(component);
+                if candidate.is_file() && found_path.replace(candidate).is_some() {
+                    return Err(NavigateError::Ambiguous);
+                }
+            }
+
+            if found_path.is_none() {
+                // Directories without init files are considered valid "intermediate" path
+                return Ok(None);
+            }
+        }
+
+        Ok(Some(found_path.ok_or(NavigateError::NotFound)?))
+    }
+}
+
+impl Require for TextRequirer {
+    fn is_require_allowed(&self, chunk_name: &str) -> bool {
+        chunk_name.starts_with(Self::CHUNK_PREFIX)
+    }
+
+    fn reset(&mut self, chunk_name: &str) -> StdResult<(), NavigateError> {
+        if !chunk_name.starts_with(Self::CHUNK_PREFIX) {
+            return Err(NavigateError::NotFound);
+        }
+        let chunk_name = Self::normalize_chunk_name(&chunk_name[1..]);
+        let chunk_path = Self::normalize_path(chunk_name.as_ref());
+
+        if chunk_path.extension() == Some("rs".as_ref()) {
+            // Special case for Rust source files, reset to the current directory
+            let chunk_filename = chunk_path.file_name().unwrap();
+            let cwd = env::current_dir().map_err(|_| NavigateError::NotFound)?;
+            self.abs_path = Self::normalize_path(&cwd.join(chunk_filename));
+            self.rel_path = ([Component::CurDir, Component::Normal(chunk_filename)].into_iter()).collect();
+            self.resolved_path = None;
+
+            return Ok(());
+        }
+
+        if chunk_path.is_absolute() {
+            let resolved_path = Self::resolve_module(&chunk_path)?;
+            self.abs_path = chunk_path.clone();
+            self.rel_path = chunk_path;
+            self.resolved_path = resolved_path;
+        } else {
+            // Relative path
+            let cwd = env::current_dir().map_err(|_| NavigateError::NotFound)?;
+            let abs_path = Self::normalize_path(&cwd.join(&chunk_path));
+            let resolved_path = Self::resolve_module(&abs_path)?;
+            self.abs_path = abs_path;
+            self.rel_path = chunk_path;
+            self.resolved_path = resolved_path;
+        }
+
+        Ok(())
+    }
+
+    fn jump_to_alias(&mut self, path: &str) -> StdResult<(), NavigateError> {
+        let path = Self::normalize_path(path.as_ref());
+        let resolved_path = Self::resolve_module(&path)?;
+
+        self.abs_path = path.clone();
+        self.rel_path = path;
+        self.resolved_path = resolved_path;
+
+        Ok(())
+    }
+
+    fn to_parent(&mut self) -> StdResult<(), NavigateError> {
+        let mut abs_path = self.abs_path.clone();
+        if !abs_path.pop() {
+            // It's important to return `NotFound` if we reached the root, as it's a "recoverable" error if we
+            // cannot go beyond the root directory.
+            // Luau "require-by-string` has a special logic to search for config file to resolve aliases.
+            return Err(NavigateError::NotFound);
+        }
+        let mut rel_parent = self.rel_path.clone();
+        rel_parent.pop();
+        let resolved_path = Self::resolve_module(&abs_path)?;
+
+        self.abs_path = abs_path;
+        self.rel_path = Self::normalize_path(&rel_parent);
+        self.resolved_path = resolved_path;
+
+        Ok(())
+    }
+
+    fn to_child(&mut self, name: &str) -> StdResult<(), NavigateError> {
+        let abs_path = self.abs_path.join(name);
+        let rel_path = self.rel_path.join(name);
+        let resolved_path = Self::resolve_module(&abs_path)?;
+
+        self.abs_path = abs_path;
+        self.rel_path = rel_path;
+        self.resolved_path = resolved_path;
+
+        Ok(())
+    }
+
+    fn has_module(&self) -> bool {
+        (self.resolved_path.as_deref())
+            .map(Path::is_file)
+            .unwrap_or(false)
+    }
+
+    fn cache_key(&self) -> String {
+        self.resolved_path.as_deref().unwrap().display().to_string()
+    }
+
+    fn has_config(&self) -> bool {
+        self.abs_path.is_dir() && self.abs_path.join(Self::LUAURC_CONFIG_FILENAME).is_file()
+            || self.abs_path.is_dir() && self.abs_path.join(Self::LUAU_CONFIG_FILENAME).is_file()
+    }
+
+    fn config(&self) -> IoResult<Vec<u8>> {
+        if self.abs_path.join(Self::LUAURC_CONFIG_FILENAME).is_file() {
+            return fs::read(self.abs_path.join(Self::LUAURC_CONFIG_FILENAME));
+        }
+        fs::read(self.abs_path.join(Self::LUAU_CONFIG_FILENAME))
+    }
+
+    fn loader(&self, lua: &Lua) -> Result<Function> {
+        let name = format!("@{}", self.rel_path.display());
+        lua.load(self.resolved_path.as_deref().unwrap())
+            .set_name(name)
+            .into_function()
+    }
+}
+
+#[cfg(test)]
+mod tests {
+    use std::path::Path;
+
+    use super::TextRequirer;
+
+    #[test]
+    fn test_path_normalize() {
+        for (input, expected) in [
+            // Basic formatting checks
+            ("", "./"),
+            (".", "./"),
+            ("a/relative/path", "./a/relative/path"),
+            // Paths containing extraneous '.' and '/' symbols
+            ("./remove/extraneous/symbols/", "./remove/extraneous/symbols"),
+            ("./remove/extraneous//symbols", "./remove/extraneous/symbols"),
+            ("./remove/extraneous/symbols/.", "./remove/extraneous/symbols"),
+            ("./remove/extraneous/./symbols", "./remove/extraneous/symbols"),
+            ("../remove/extraneous/symbols/", "../remove/extraneous/symbols"),
+            ("../remove/extraneous//symbols", "../remove/extraneous/symbols"),
+            ("../remove/extraneous/symbols/.", "../remove/extraneous/symbols"),
+            ("../remove/extraneous/./symbols", "../remove/extraneous/symbols"),
+            ("/remove/extraneous/symbols/", "/remove/extraneous/symbols"),
+            ("/remove/extraneous//symbols", "/remove/extraneous/symbols"),
+            ("/remove/extraneous/symbols/.", "/remove/extraneous/symbols"),
+            ("/remove/extraneous/./symbols", "/remove/extraneous/symbols"),
+            // Paths containing '..'
+            ("./remove/me/..", "./remove"),
+            ("./remove/me/../", "./remove"),
+            ("../remove/me/..", "../remove"),
+            ("../remove/me/../", "../remove"),
+            ("/remove/me/..", "/remove"),
+            ("/remove/me/../", "/remove"),
+            ("./..", "../"),
+            ("./../", "../"),
+            ("../..", "../../"),
+            ("../../", "../../"),
+            // '..' disappears if path is absolute and component is non-erasable
+            ("/../", "/"),
+        ] {
+            let path = TextRequirer::normalize_path(input.as_ref());
+            assert_eq!(
+                &path,
+                expected.as_ref() as &Path,
+                "wrong normalization for {input}"
+            );
+        }
+    }
+}