clean up

Author: Boshen

src/file_system.rs

@@ -155,53 +155,19 @@ impl FileSystemOs {
     /// See [std::fs::read_link]
     #[inline]
     pub fn read_link(path: &Path) -> io::Result<PathBuf> {
-        let target = fs::read_link(path)?;
+        let path = fs::read_link(path)?;
         cfg_if! {
-            if #[cfg(windows)] {
-                Ok(match Self::try_strip_windows_prefix(&target) {
-                    Some(path) => path,
+            if #[cfg(target_os = "windows")] {
+                match crate::windows::try_strip_windows_prefix(path) {
                     // We won't follow the link if we cannot represent its target properly.
-                    None => target,
-                })
+                    Ok(p) | Err(crate::ResolveError::PathNotSupported(p)) => Ok(p),
+                    _ => unreachable!(),
+                }
             } else {
-                Ok(target.to_path_buf())
+                Ok(path)
             }
         }
     }
-
-    /// When applicable, converts a [DOS device path](https://learn.microsoft.com/en-us/dotnet/standard/io/file-path-formats#dos-device-paths)
-    /// to a normal path (usually, "Traditional DOS paths" or "UNC path") that can be consumed by the `import`/`require` syntax of Node.js.
-    /// Returns `None` if the path cannot be represented as a normal path.
-    pub fn try_strip_windows_prefix<P: AsRef<Path>>(path: P) -> Option<PathBuf> {
-        // See https://learn.microsoft.com/en-us/windows/win32/fileio/naming-a-file
-        let path_bytes = path.as_ref().as_os_str().as_encoded_bytes();
-
-        let path = if let Some(p) =
-            path_bytes.strip_prefix(br"\\?\UNC\").or(path_bytes.strip_prefix(br"\\.\UNC\"))
-        {
-            // UNC paths
-            unsafe {
-                PathBuf::from(std::ffi::OsStr::from_encoded_bytes_unchecked(&[br"\\", p].concat()))
-            }
-        } else if let Some(p) =
-            path_bytes.strip_prefix(br"\\?\").or(path_bytes.strip_prefix(br"\\.\"))
-        {
-            // Assuming traditional DOS path "\\?\C:\"
-            if p[1] != b':' {
-                // E.g.,
-                // \\?\Volume{b75e2c83-0000-0000-0000-602f00000000}
-                // \\?\BootPartition\
-                // It seems nodejs does not support DOS device paths with Volume GUIDs.
-                // This can happen if the path points to a Mounted Volume without a drive letter.
-                return None;
-            }
-            unsafe { PathBuf::from(std::ffi::OsStr::from_encoded_bytes_unchecked(p)) }
-        } else {
-            path.as_ref().to_path_buf()
-        };
-
-        Some(path)
-    }
 }
 
 impl FileSystem for FileSystemOs {
@@ -267,37 +233,3 @@ fn metadata() {
     );
     let _ = meta;
 }
-
-#[test]
-fn test_strip_windows_prefix() {
-    assert_eq!(
-        FileSystemOs::try_strip_windows_prefix(PathBuf::from(
-            r"\\?\C:\Users\user\Documents\file.txt"
-        )),
-        Some(PathBuf::from(r"C:\Users\user\Documents\file.txt"))
-    );
-
-    assert_eq!(
-        FileSystemOs::try_strip_windows_prefix(PathBuf::from(
-            r"\\.\C:\Users\user\Documents\file.txt"
-        )),
-        Some(PathBuf::from(r"C:\Users\user\Documents\file.txt"))
-    );
-
-    assert_eq!(
-        FileSystemOs::try_strip_windows_prefix(PathBuf::from(r"\\?\UNC\server\share\file.txt")),
-        Some(PathBuf::from(r"\\server\share\file.txt"))
-    );
-
-    assert_eq!(
-        FileSystemOs::try_strip_windows_prefix(PathBuf::from(
-            r"\\?\Volume{c8ec34d8-3ba6-45c3-9b9d-3e4148e12d00}\file.txt"
-        )),
-        None
-    );
-
-    assert_eq!(
-        FileSystemOs::try_strip_windows_prefix(PathBuf::from(r"\\?\BootPartition\file.txt")),
-        None
-    );
-}

src/fs_cache.rs

@@ -79,11 +79,8 @@ impl<Fs: FileSystem> Cache for FsCache<Fs> {
         let cached_path = self.canonicalize_impl(path)?;
         let path = cached_path.to_path_buf();
         cfg_if! {
-            if #[cfg(windows)] {
-                match crate::FileSystemOs::try_strip_windows_prefix(&path) {
-                    Some(path) => Ok(path),
-                    None => Err(ResolveError::PathNotSupported(path)),
-                }
+            if #[cfg(target_os = "windows")] {
+                crate::windows::try_strip_windows_prefix(path)
             } else {
                 Ok(path)
             }

src/lib.rs

@@ -65,6 +65,8 @@ mod specifier;
 mod tsconfig;
 #[cfg(feature = "fs_cache")]
 mod tsconfig_serde;
+#[cfg(target_os = "windows")]
+mod windows;
 
 #[cfg(test)]
 mod tests;

src/windows.rs

@@ -0,0 +1,64 @@
+use std::path::PathBuf;
+
+use crate::ResolveError;
+
+/// When applicable, converts a [DOS device path](https://learn.microsoft.com/en-us/dotnet/standard/io/file-path-formats#dos-device-paths)
+/// to a normal path (usually, "Traditional DOS paths" or "UNC path") that can be consumed by the `import`/`require` syntax of Node.js.
+/// Returns `None` if the path cannot be represented as a normal path.
+pub fn try_strip_windows_prefix(path: PathBuf) -> Result<PathBuf, ResolveError> {
+    // See https://learn.microsoft.com/en-us/windows/win32/fileio/naming-a-file
+    let path_bytes = path.as_os_str().as_encoded_bytes();
+
+    let path = if let Some(p) =
+        path_bytes.strip_prefix(br"\\?\UNC\").or_else(|| path_bytes.strip_prefix(br"\\.\UNC\"))
+    {
+        // UNC paths
+        // SAFETY:
+        unsafe {
+            PathBuf::from(std::ffi::OsStr::from_encoded_bytes_unchecked(&[br"\\", p].concat()))
+        }
+    } else if let Some(p) =
+        path_bytes.strip_prefix(br"\\?\").or_else(|| path_bytes.strip_prefix(br"\\.\"))
+    {
+        // Assuming traditional DOS path "\\?\C:\"
+        if p[1] != b':' {
+            // E.g.,
+            // \\?\Volume{b75e2c83-0000-0000-0000-602f00000000}
+            // \\?\BootPartition\
+            // It seems nodejs does not support DOS device paths with Volume GUIDs.
+            // This can happen if the path points to a Mounted Volume without a drive letter.
+            return Err(ResolveError::PathNotSupported(path));
+        }
+        // SAFETY:
+        unsafe { PathBuf::from(std::ffi::OsStr::from_encoded_bytes_unchecked(p)) }
+    } else {
+        path
+    };
+
+    Ok(path)
+}
+
+#[test]
+fn test_try_strip_windows_prefix() {
+    let pass = [
+        (r"\\?\C:\Users\user\Documents\file1.txt", r"C:\Users\user\Documents\file1.txt"),
+        (r"\\.\C:\Users\user\Documents\file2.txt", r"C:\Users\user\Documents\file2.txt"),
+        (r"\\?\UNC\server\share\file3.txt", r"\\server\share\file3.txt"),
+    ];
+
+    for (path, expected) in pass {
+        assert_eq!(try_strip_windows_prefix(PathBuf::from(path)), Ok(PathBuf::from(expected)));
+    }
+
+    let fail = [
+        r"\\?\Volume{c8ec34d8-3ba6-45c3-9b9d-3e4148e12d00}\file4.txt",
+        r"\\?\BootPartition\file4.txt",
+    ];
+
+    for path in fail {
+        assert_eq!(
+            try_strip_windows_prefix(PathBuf::from(path)),
+            Err(crate::ResolveError::PathNotSupported(PathBuf::from(path)))
+        );
+    }
+}