1 files changed, 42 insertions, 0 deletions
diff --git a/cli/fs_util.rs b/cli/fs_util.rs
index 322b3f9e7..69d4f7248 100644
--- a/cli/fs_util.rs
+++ b/cli/fs_util.rs
@@ -447,6 +447,48 @@ pub fn path_with_stem_suffix(path: &Path, suffix: &str) -> PathBuf {
   }
 }
 
+/// Gets if the provided character is not supported on all
+/// kinds of file systems.
+pub fn is_banned_path_char(c: char) -> bool {
+  matches!(c, '<' | '>' | ':' | '"' | '|' | '?' | '*')
+}
+
+/// Gets a safe local directory name for the provided url.
+///
+/// For example:
+/// https://deno.land:8080/path -> deno.land_8080/path
+pub fn root_url_to_safe_local_dirname(root: &ModuleSpecifier) -> PathBuf {
+  fn sanitize_segment(text: &str) -> String {
+    text
+      .chars()
+      .map(|c| if is_banned_segment_char(c) { '_' } else { c })
+      .collect()
+  }
+
+  fn is_banned_segment_char(c: char) -> bool {
+    matches!(c, '/' | '\\') || is_banned_path_char(c)
+  }
+
+  let mut result = String::new();
+  if let Some(domain) = root.domain() {
+    result.push_str(&sanitize_segment(domain));
+  }
+  if let Some(port) = root.port() {
+    if !result.is_empty() {
+      result.push('_');
+    }
+    result.push_str(&port.to_string());
+  }
+  let mut result = PathBuf::from(result);
+  if let Some(segments) = root.path_segments() {
+    for segment in segments.filter(|s| !s.is_empty()) {
+      result = result.join(sanitize_segment(segment));
+    }
+  }
+
+  result
+}
+
 #[cfg(test)]
 mod tests {
   use super::*;