1 files changed, 179 insertions, 0 deletions
diff --git a/resolvers/node/path.rs b/resolvers/node/path.rs
new file mode 100644
index 000000000..ece270cd9
--- /dev/null
+++ b/resolvers/node/path.rs
@@ -0,0 +1,179 @@
+// Copyright 2018-2024 the Deno authors. All rights reserved. MIT license.
+
+use std::path::Component;
+use std::path::Path;
+use std::path::PathBuf;
+
+use url::Url;
+
+/// Extension to path_clean::PathClean
+pub trait PathClean<T> {
+  fn clean(&self) -> T;
+}
+
+impl PathClean<PathBuf> for PathBuf {
+  fn clean(&self) -> PathBuf {
+    fn is_clean_path(path: &Path) -> bool {
+      let path = path.to_string_lossy();
+      let mut current_index = 0;
+      while let Some(index) = path[current_index..].find("\\.") {
+        let trailing_index = index + current_index + 2;
+        let mut trailing_chars = path[trailing_index..].chars();
+        match trailing_chars.next() {
+          Some('.') => match trailing_chars.next() {
+            Some('/') | Some('\\') | None => {
+              return false;
+            }
+            _ => {}
+          },
+          Some('/') | Some('\\') => {
+            return false;
+          }
+          _ => {}
+        }
+        current_index = trailing_index;
+      }
+      true
+    }
+
+    let path = path_clean::PathClean::clean(self);
+    if cfg!(windows) && !is_clean_path(&path) {
+      // temporary workaround because path_clean::PathClean::clean is
+      // not good enough on windows
+      let mut components = Vec::new();
+
+      for component in path.components() {
+        match component {
+          Component::CurDir => {
+            // skip
+          }
+          Component::ParentDir => {
+            let maybe_last_component = components.pop();
+            if !matches!(maybe_last_component, Some(Component::Normal(_))) {
+              panic!("Error normalizing: {}", path.display());
+            }
+          }
+          Component::Normal(_) | Component::RootDir | Component::Prefix(_) => {
+            components.push(component);
+          }
+        }
+      }
+      components.into_iter().collect::<PathBuf>()
+    } else {
+      path
+    }
+  }
+}
+
+pub(crate) fn to_file_specifier(path: &Path) -> Url {
+  match Url::from_file_path(path) {
+    Ok(url) => url,
+    Err(_) => panic!("Invalid path: {}", path.display()),
+  }
+}
+
+// todo(dsherret): we have the below code also in deno_core and it
+// would be good to somehow re-use it in both places (we don't want
+// to create a dependency on deno_core here)
+
+#[cfg(not(windows))]
+#[inline]
+pub fn strip_unc_prefix(path: PathBuf) -> PathBuf {
+  path
+}
+
+/// Strips the unc prefix (ex. \\?\) from Windows paths.
+#[cfg(windows)]
+pub fn strip_unc_prefix(path: PathBuf) -> PathBuf {
+  use std::path::Component;
+  use std::path::Prefix;
+
+  let mut components = path.components();
+  match components.next() {
+    Some(Component::Prefix(prefix)) => {
+      match prefix.kind() {
+        // \\?\device
+        Prefix::Verbatim(device) => {
+          let mut path = PathBuf::new();
+          path.push(format!(r"\\{}\", device.to_string_lossy()));
+          path.extend(components.filter(|c| !matches!(c, Component::RootDir)));
+          path
+        }
+        // \\?\c:\path
+        Prefix::VerbatimDisk(_) => {
+          let mut path = PathBuf::new();
+          path.push(prefix.as_os_str().to_string_lossy().replace(r"\\?\", ""));
+          path.extend(components);
+          path
+        }
+        // \\?\UNC\hostname\share_name\path
+        Prefix::VerbatimUNC(hostname, share_name) => {
+          let mut path = PathBuf::new();
+          path.push(format!(
+            r"\\{}\{}\",
+            hostname.to_string_lossy(),
+            share_name.to_string_lossy()
+          ));
+          path.extend(components.filter(|c| !matches!(c, Component::RootDir)));
+          path
+        }
+        _ => path,
+      }
+    }
+    _ => path,
+  }
+}
+
+#[cfg(test)]
+mod test {
+  #[cfg(windows)]
+  #[test]
+  fn test_path_clean() {
+    use super::*;
+
+    run_test("C:\\test\\./file.txt", "C:\\test\\file.txt");
+    run_test("C:\\test\\../other/file.txt", "C:\\other\\file.txt");
+    run_test("C:\\test\\../other\\file.txt", "C:\\other\\file.txt");
+
+    fn run_test(input: &str, expected: &str) {
+      assert_eq!(PathBuf::from(input).clean(), PathBuf::from(expected));
+    }
+  }
+
+  #[cfg(windows)]
+  #[test]
+  fn test_strip_unc_prefix() {
+    use std::path::PathBuf;
+
+    run_test(r"C:\", r"C:\");
+    run_test(r"C:\test\file.txt", r"C:\test\file.txt");
+
+    run_test(r"\\?\C:\", r"C:\");
+    run_test(r"\\?\C:\test\file.txt", r"C:\test\file.txt");
+
+    run_test(r"\\.\C:\", r"\\.\C:\");
+    run_test(r"\\.\C:\Test\file.txt", r"\\.\C:\Test\file.txt");
+
+    run_test(r"\\?\UNC\localhost\", r"\\localhost");
+    run_test(r"\\?\UNC\localhost\c$\", r"\\localhost\c$");
+    run_test(
+      r"\\?\UNC\localhost\c$\Windows\file.txt",
+      r"\\localhost\c$\Windows\file.txt",
+    );
+    run_test(r"\\?\UNC\wsl$\deno.json", r"\\wsl$\deno.json");
+
+    run_test(r"\\?\server1", r"\\server1");
+    run_test(r"\\?\server1\e$\", r"\\server1\e$\");
+    run_test(
+      r"\\?\server1\e$\test\file.txt",
+      r"\\server1\e$\test\file.txt",
+    );
+
+    fn run_test(input: &str, expected: &str) {
+      assert_eq!(
+        super::strip_unc_prefix(PathBuf::from(input)),
+        PathBuf::from(expected)
+      );
+    }
+  }
+}