A special url always has a path. A path always starts with '/'

Author: o0Ignition0o

src/parser.rs

@@ -798,8 +798,24 @@ impl<'a> Parser<'a> {
                 self.serialization.push_str(before_query);
                 // FIXME spec says just "remove last entry", not the "pop" algorithm
                 self.pop_path(scheme_type, base_url.path_start as usize);
-                let remaining =
-                    self.parse_path(scheme_type, &mut true, base_url.path_start as usize, input);
+                // A special url always has a path.
+                // A path always starts with '/'
+                if self.serialization.len() == base_url.path_start as usize {
+                    if SchemeType::from(base_url.scheme()).is_special() || !input.is_empty() {
+                        self.serialization.push('/');
+                    }
+                }
+                let remaining = match input.split_first() {
+                    (Some('/'), remaining) => self.parse_path(
+                        scheme_type,
+                        &mut true,
+                        base_url.path_start as usize,
+                        remaining,
+                    ),
+                    _ => {
+                        self.parse_path(scheme_type, &mut true, base_url.path_start as usize, input)
+                    }
+                };
                 self.with_query_and_fragment(
                     scheme_type,
                     base_url.scheme_end,