perf: optimize URL serialization (#15663)

4 files changed, 394 insertions, 136 deletions

diff --git a/cli/bench/url_parse.js b/cli/bench/url_parse.js
new file mode 100644
index 000000000..d19793f63
--- /dev/null
+++ b/cli/bench/url_parse.js
@@ -0,0 +1,22 @@
+// Copyright 2018-2022 the Deno authors. All rights reserved. MIT license.
+const queueMicrotask = globalThis.queueMicrotask || process.nextTick;
+let [total, count] = typeof Deno !== "undefined"
+  ? Deno.args
+  : [process.argv[2], process.argv[3]];
+
+total = total ? parseInt(total, 0) : 50;
+count = count ? parseInt(count, 10) : 10000000;
+
+function bench(fun) {
+  const start = Date.now();
+  for (let i = 0; i < count; i++) fun();
+  const elapsed = Date.now() - start;
+  const rate = Math.floor(count / (elapsed / 1000));
+  console.log(`time ${elapsed} ms rate ${rate}`);
+  if (--total) queueMicrotask(() => bench(fun));
+}
+
+bench(() => {
+  const url = new URL("http://example.com/");
+  url.pathname;
+});
diff --git a/core/Cargo.toml b/core/Cargo.toml
index 3e62663e3..f6628531a 100644
--- a/core/Cargo.toml
+++ b/core/Cargo.toml
@@ -32,7 +32,7 @@ serde = { version = "1.0.136", features = ["derive"] }
 serde_json = { version = "1.0.79", features = ["preserve_order"] }
 serde_v8 = { version = "0.61.0", path = "../serde_v8" }
 sourcemap = "=6.0.1"
-url = { version = "2.3.1", features = ["serde"] }
+url = { version = "2.3.1", features = ["serde", "expose_internals"] }
 v8 = { version = "0.49.0", default-features = false }
 
 [[example]]
diff --git a/ext/url/00_url.js b/ext/url/00_url.js
index ab87e85e0..659e6a37b 100644
--- a/ext/url/00_url.js
+++ b/ext/url/00_url.js
@@ -19,9 +19,9 @@
     ArrayPrototypeSort,
     ArrayPrototypeSplice,
     ObjectKeys,
+    Uint32Array,
     SafeArrayIterator,
     StringPrototypeSlice,
-    StringPrototypeSplit,
     Symbol,
     SymbolFor,
     SymbolIterator,
@@ -44,41 +44,37 @@
 
   // Helper functions
   function opUrlReparse(href, setter, value) {
-    return _urlParts(
-      ops.op_url_reparse(href, [setter, value]),
+    const status = ops.op_url_reparse(
+      href,
+      setter,
+      value,
+      componentsBuf.buffer,
     );
+    return getSerialization(status, href);
   }
+
   function opUrlParse(href, maybeBase) {
-    return _urlParts(ops.op_url_parse(href, maybeBase));
+    let status;
+    if (maybeBase === undefined) {
+      status = ops.op_url_parse(href, componentsBuf.buffer);
+    } else {
+      status = core.ops.op_url_parse_with_base(
+        href,
+        maybeBase,
+        componentsBuf.buffer,
+      );
+    }
+    return getSerialization(status, href);
   }
-  function _urlParts(internalParts) {
-    // WARNING: must match UrlParts serialization rust's url_result()
-    const {
-      0: href,
-      1: hash,
-      2: host,
-      3: hostname,
-      4: origin,
-      5: password,
-      6: pathname,
-      7: port,
-      8: protocol,
-      9: search,
-      10: username,
-    } = StringPrototypeSplit(internalParts, "\n");
-    return {
-      href,
-      hash,
-      host,
-      hostname,
-      origin,
-      password,
-      pathname,
-      port,
-      protocol,
-      search,
-      username,
-    };
+
+  function getSerialization(status, href) {
+    if (status === 0) {
+      return href;
+    } else if (status === 1) {
+      return core.ops.op_url_get_serialization();
+    } else {
+      throw new TypeError("Invalid URL");
+    }
   }
 
   class URLSearchParams {
@@ -131,7 +127,7 @@
       if (url === null) {
         return;
       }
-      url[_url] = opUrlReparse(url.href, SET_SEARCH, this.toString());
+      url[_updateUrlSearch](this.toString());
     }
 
     /**
@@ -308,11 +304,37 @@
     URLSearchParamsPrototype,
   );
 
-  const _url = Symbol("url");
+  const _updateUrlSearch = Symbol("updateUrlSearch");
+
+  function trim(s) {
+    if (s.length === 1) return "";
+    return s;
+  }
+
+  // Represents a "no port" value. A port in URL cannot be greater than 2^16 − 1
+  const NO_PORT = 65536;
 
+  const componentsBuf = new Uint32Array(8);
   class URL {
-    [_url];
     #queryObject = null;
+    #serialization;
+    #schemeEnd;
+    #usernameEnd;
+    #hostStart;
+    #hostEnd;
+    #port;
+    #pathStart;
+    #queryStart;
+    #fragmentStart;
+
+    [_updateUrlSearch](value) {
+      this.#serialization = opUrlReparse(
+        this.#serialization,
+        SET_SEARCH,
+        value,
+      );
+      this.#updateComponents();
+    }
 
     /**
      * @param {string} url
@@ -328,7 +350,21 @@
         });
       }
       this[webidl.brand] = webidl.brand;
-      this[_url] = opUrlParse(url, base);
+      this.#serialization = opUrlParse(url, base);
+      this.#updateComponents();
+    }
+
+    #updateComponents() {
+      [
+        this.#schemeEnd,
+        this.#usernameEnd,
+        this.#hostStart,
+        this.#hostEnd,
+        this.#port,
+        this.#pathStart,
+        this.#queryStart,
+        this.#fragmentStart,
+      ] = componentsBuf;
     }
 
     [SymbolFor("Deno.privateCustomInspect")](inspect, inspectOptions) {
@@ -363,10 +399,18 @@
       }
     }
 
+    #hasAuthority() {
+      // https://github.com/servo/rust-url/blob/1d307ae51a28fecc630ecec03380788bfb03a643/url/src/lib.rs#L824
+      return this.#serialization.slice(this.#schemeEnd).startsWith("://");
+    }
+
     /** @return {string} */
     get hash() {
       webidl.assertBranded(this, URLPrototype);
-      return this[_url].hash;
+      // https://github.com/servo/rust-url/blob/1d307ae51a28fecc630ecec03380788bfb03a643/url/src/quirks.rs#L263
+      return this.#fragmentStart
+        ? trim(this.#serialization.slice(this.#fragmentStart))
+        : "";
     }
 
     /** @param {string} value */
@@ -379,7 +423,12 @@
         context: "Argument 1",
       });
       try {
-        this[_url] = opUrlReparse(this[_url].href, SET_HASH, value);
+        this.#serialization = opUrlReparse(
+          this.#serialization,
+          SET_HASH,
+          value,
+        );
+        this.#updateComponents();
       } catch {
         /* pass */
       }
@@ -388,7 +437,8 @@
     /** @return {string} */
     get host() {
       webidl.assertBranded(this, URLPrototype);
-      return this[_url].host;
+      // https://github.com/servo/rust-url/blob/1d307ae51a28fecc630ecec03380788bfb03a643/url/src/quirks.rs#L101
+      return this.#serialization.slice(this.#hostStart, this.#pathStart);
     }
 
     /** @param {string} value */
@@ -401,7 +451,12 @@
         context: "Argument 1",
       });
       try {
-        this[_url] = opUrlReparse(this[_url].href, SET_HOST, value);
+        this.#serialization = opUrlReparse(
+          this.#serialization,
+          SET_HOST,
+          value,
+        );
+        this.#updateComponents();
       } catch {
         /* pass */
       }
@@ -410,7 +465,8 @@
     /** @return {string} */
     get hostname() {
       webidl.assertBranded(this, URLPrototype);
-      return this[_url].hostname;
+      // https://github.com/servo/rust-url/blob/1d307ae51a28fecc630ecec03380788bfb03a643/url/src/lib.rs#L988
+      return this.#serialization.slice(this.#hostStart, this.#hostEnd);
     }
 
     /** @param {string} value */
@@ -423,7 +479,12 @@
         context: "Argument 1",
       });
       try {
-        this[_url] = opUrlReparse(this[_url].href, SET_HOSTNAME, value);
+        this.#serialization = opUrlReparse(
+          this.#serialization,
+          SET_HOSTNAME,
+          value,
+        );
+        this.#updateComponents();
       } catch {
         /* pass */
       }
@@ -432,7 +493,7 @@
     /** @return {string} */
     get href() {
       webidl.assertBranded(this, URLPrototype);
-      return this[_url].href;
+      return this.#serialization;
     }
 
     /** @param {string} value */
@@ -444,20 +505,50 @@
         prefix,
         context: "Argument 1",
       });
-      this[_url] = opUrlParse(value);
+      this.#serialization = opUrlParse(value);
+      this.#updateComponents();
       this.#updateSearchParams();
     }
 
     /** @return {string} */
     get origin() {
       webidl.assertBranded(this, URLPrototype);
-      return this[_url].origin;
+      // https://github.com/servo/rust-url/blob/1d307ae51a28fecc630ecec03380788bfb03a643/url/src/origin.rs#L14
+      const scheme = this.#serialization.slice(0, this.#schemeEnd);
+      if (
+        scheme === "http" || scheme === "https" || scheme === "ftp" ||
+        scheme === "ws" || scheme === "wss"
+      ) {
+        return `${scheme}://${this.host}`;
+      }
+
+      if (scheme === "blob") {
+        // TODO(@littledivy): Fast path.
+        try {
+          return new URL(this.pathname).origin;
+        } catch {
+          return "null";
+        }
+      }
+
+      return "null";
     }
 
     /** @return {string} */
     get password() {
       webidl.assertBranded(this, URLPrototype);
-      return this[_url].password;
+      // https://github.com/servo/rust-url/blob/1d307ae51a28fecc630ecec03380788bfb03a643/url/src/lib.rs#L914
+      if (
+        this.#hasAuthority() &&
+        this.#usernameEnd !== this.#serialization.length &&
+        this.#serialization[this.#usernameEnd] === ":"
+      ) {
+        return this.#serialization.slice(
+          this.#usernameEnd + 1,
+          this.#hostStart - 1,
+        );
+      }
+      return "";
     }
 
     /** @param {string} value */
@@ -470,7 +561,12 @@
         context: "Argument 1",
       });
       try {
-        this[_url] = opUrlReparse(this[_url].href, SET_PASSWORD, value);
+        this.#serialization = opUrlReparse(
+          this.#serialization,
+          SET_PASSWORD,
+          value,
+        );
+        this.#updateComponents();
       } catch {
         /* pass */
       }
@@ -479,7 +575,13 @@
     /** @return {string} */
     get pathname() {
       webidl.assertBranded(this, URLPrototype);
-      return this[_url].pathname;
+      // https://github.com/servo/rust-url/blob/1d307ae51a28fecc630ecec03380788bfb03a643/url/src/lib.rs#L1203
+      if (!this.#queryStart && !this.#fragmentStart) {
+        return this.#serialization.slice(this.#pathStart);
+      }
+
+      const nextComponentStart = this.#queryStart || this.#fragmentStart;
+      return this.#serialization.slice(this.#pathStart, nextComponentStart);
     }
 
     /** @param {string} value */
@@ -492,7 +594,12 @@
         context: "Argument 1",
       });
       try {
-        this[_url] = opUrlReparse(this[_url].href, SET_PATHNAME, value);
+        this.#serialization = opUrlReparse(
+          this.#serialization,
+          SET_PATHNAME,
+          value,
+        );
+        this.#updateComponents();
       } catch {
         /* pass */
       }
@@ -501,7 +608,15 @@
     /** @return {string} */
     get port() {
       webidl.assertBranded(this, URLPrototype);
-      return this[_url].port;
+      // https://github.com/servo/rust-url/blob/1d307ae51a28fecc630ecec03380788bfb03a643/url/src/quirks.rs#L196
+      if (this.#port === NO_PORT) {
+        return this.#serialization.slice(this.#hostEnd, this.#pathStart);
+      } else {
+        return this.#serialization.slice(
+          this.#hostEnd + 1, /* : */
+          this.#pathStart,
+        );
+      }
     }
 
     /** @param {string} value */
@@ -514,7 +629,12 @@
         context: "Argument 1",
       });
       try {
-        this[_url] = opUrlReparse(this[_url].href, SET_PORT, value);
+        this.#serialization = opUrlReparse(
+          this.#serialization,
+          SET_PORT,
+          value,
+        );
+        this.#updateComponents();
       } catch {
         /* pass */
       }
@@ -523,7 +643,8 @@
     /** @return {string} */
     get protocol() {
       webidl.assertBranded(this, URLPrototype);
-      return this[_url].protocol;
+      // https://github.com/servo/rust-url/blob/1d307ae51a28fecc630ecec03380788bfb03a643/url/src/quirks.rs#L56
+      return this.#serialization.slice(0, this.#schemeEnd + 1 /* : */);
     }
 
     /** @param {string} value */
@@ -536,7 +657,12 @@
         context: "Argument 1",
       });
       try {
-        this[_url] = opUrlReparse(this[_url].href, SET_PROTOCOL, value);
+        this.#serialization = opUrlReparse(
+          this.#serialization,
+          SET_PROTOCOL,
+          value,
+        );
+        this.#updateComponents();
       } catch {
         /* pass */
       }
@@ -545,7 +671,11 @@
     /** @return {string} */
     get search() {
       webidl.assertBranded(this, URLPrototype);
-      return this[_url].search;
+      // https://github.com/servo/rust-url/blob/1d307ae51a28fecc630ecec03380788bfb03a643/url/src/quirks.rs#L249
+      const afterPath = this.#queryStart || this.#fragmentStart ||
+        this.#serialization.length;
+      const afterQuery = this.#fragmentStart || this.#serialization.length;
+      return trim(this.#serialization.slice(afterPath, afterQuery));
     }
 
     /** @param {string} value */
@@ -558,7 +688,12 @@
         context: "Argument 1",
       });
       try {
-        this[_url] = opUrlReparse(this[_url].href, SET_SEARCH, value);
+        this.#serialization = opUrlReparse(
+          this.#serialization,
+          SET_SEARCH,
+          value,
+        );
+        this.#updateComponents();
         this.#updateSearchParams();
       } catch {
         /* pass */
@@ -568,7 +703,19 @@
     /** @return {string} */
     get username() {
       webidl.assertBranded(this, URLPrototype);
-      return this[_url].username;
+      // https://github.com/servo/rust-url/blob/1d307ae51a28fecc630ecec03380788bfb03a643/url/src/lib.rs#L881
+      const schemeSeperatorLen = 3; /* :// */
+      if (
+        this.#hasAuthority() &&
+        this.#usernameEnd > this.#schemeEnd + schemeSeperatorLen
+      ) {
+        return this.#serialization.slice(
+          this.#schemeEnd + schemeSeperatorLen,
+          this.#usernameEnd,
+        );
+      } else {
+        return "";
+      }
     }
 
     /** @param {string} value */
@@ -581,7 +728,12 @@
         context: "Argument 1",
       });
       try {
-        this[_url] = opUrlReparse(this[_url].href, SET_USERNAME, value);
+        this.#serialization = opUrlReparse(
+          this.#serialization,
+          SET_USERNAME,
+          value,
+        );
+        this.#updateComponents();
       } catch {
         /* pass */
       }
@@ -599,13 +751,13 @@
     /** @return {string} */
     toString() {
       webidl.assertBranded(this, URLPrototype);
-      return this[_url].href;
+      return this.#serialization;
     }
 
     /** @return {string} */
     toJSON() {
       webidl.assertBranded(this, URLPrototype);
-      return this[_url].href;
+      return this.#serialization;
     }
   }
 
diff --git a/ext/url/lib.rs b/ext/url/lib.rs
index be229cec5..c6e91e155 100644
--- a/ext/url/lib.rs
+++ b/ext/url/lib.rs
@@ -3,7 +3,6 @@
 mod urlpattern;
 
 use deno_core::error::type_error;
-use deno_core::error::uri_error;
 use deno_core::error::AnyError;
 use deno_core::include_js_files;
 use deno_core::op;
@@ -11,6 +10,7 @@ use deno_core::url::form_urlencoded;
 use deno_core::url::quirks;
 use deno_core::url::Url;
 use deno_core::Extension;
+use deno_core::OpState;
 use deno_core::ZeroCopyBuf;
 use std::path::PathBuf;
 
@@ -25,8 +25,10 @@ pub fn init() -> Extension {
       "01_urlpattern.js",
     ))
     .ops(vec![
-      op_url_parse::decl(),
       op_url_reparse::decl(),
+      op_url_parse::decl(),
+      op_url_get_serialization::decl(),
+      op_url_parse_with_base::decl(),
       op_url_parse_search_params::decl(),
       op_url_stringify_search_params::decl(),
       op_urlpattern_parse::decl(),
@@ -35,41 +37,95 @@ pub fn init() -> Extension {
     .build()
 }
 
-// UrlParts is a \n joined string of the following parts:
-// #[derive(Serialize)]
-// pub struct UrlParts {
-//   href: String,
-//   hash: String,
-//   host: String,
-//   hostname: String,
-//   origin: String,
-//   password: String,
-//   pathname: String,
-//   port: String,
-//   protocol: String,
-//   search: String,
-//   username: String,
-// }
-// TODO: implement cleaner & faster serialization
-type UrlParts = String;
-
-/// Parse `UrlParseArgs::href` with an optional `UrlParseArgs::base_href`, or an
-/// optional part to "set" after parsing. Return `UrlParts`.
+/// Parse `href` with a `base_href`. Fills the out `buf` with URL components.
 #[op]
-pub fn op_url_parse(
+pub fn op_url_parse_with_base(
+  state: &mut OpState,
+  href: String,
+  base_href: String,
+  buf: &mut [u8],
+) -> u32 {
+  let base_url = match Url::parse(&base_href) {
+    Ok(url) => url,
+    Err(_) => return ParseStatus::Err as u32,
+  };
+  parse_url(state, href, Some(&base_url), buf)
+}
+
+#[repr(u32)]
+pub enum ParseStatus {
+  Ok = 0,
+  OkSerialization = 1,
+  Err,
+}
+
+struct UrlSerialization(String);
+
+#[op]
+pub fn op_url_get_serialization(state: &mut OpState) -> String {
+  state.take::<UrlSerialization>().0
+}
+
+/// Parse `href` without a `base_url`. Fills the out `buf` with URL components.
+#[op]
+pub fn op_url_parse(state: &mut OpState, href: String, buf: &mut [u8]) -> u32 {
+  parse_url(state, href, None, buf)
+}
+
+/// `op_url_parse` and `op_url_parse_with_base` share the same implementation.
+///
+/// This function is used to parse the URL and fill the `buf` with internal
+/// offset values of the URL components.
+///
+/// If the serialized URL is the same as the input URL, then `UrlSerialization` is
+/// not set and returns `ParseStatus::Ok`.
+///
+/// If the serialized URL is different from the input URL, then `UrlSerialization` is
+/// set and returns `ParseStatus::OkSerialization`. JS side should check status and
+/// use `op_url_get_serialization` to get the serialized URL.
+///
+/// If the URL is invalid, then `UrlSerialization` is not set and returns `ParseStatus::Err`.
+///
+/// ```js
+/// const buf = new Uint32Array(8);
+/// const status = op_url_parse("http://example.com", buf.buffer);
+/// let serializedUrl = "";
+/// if (status === ParseStatus.Ok) {
+///   serializedUrl = "http://example.com";
+/// } else if (status === ParseStatus.OkSerialization) {
+///   serializedUrl = op_url_get_serialization();
+/// }
+/// ```
+#[inline]
+fn parse_url(
+  state: &mut OpState,
   href: String,
-  base_href: Option<String>,
-) -> Result<UrlParts, AnyError> {
-  let base_url = base_href
-    .as_ref()
-    .map(|b| Url::parse(b).map_err(|_| type_error("Invalid base URL")))
-    .transpose()?;
-  let url = Url::options()
-    .base_url(base_url.as_ref())
-    .parse(&href)
-    .map_err(|_| type_error("Invalid URL"))?;
-
-  Ok(url_parts(url))
+  base_href: Option<&Url>,
+  buf: &mut [u8],
+) -> u32 {
+  match Url::options().base_url(base_href).parse(&href) {
+    Ok(url) => {
+      let inner_url = quirks::internal_components(&url);
+
+      let buf: &mut [u32] = as_u32_slice(buf);
+      buf[0] = inner_url.scheme_end;
+      buf[1] = inner_url.username_end;
+      buf[2] = inner_url.host_start;
+      buf[3] = inner_url.host_end;
+      buf[4] = inner_url.port.unwrap_or(0) as u32;
+      buf[5] = inner_url.path_start;
+      buf[6] = inner_url.query_start.unwrap_or(0);
+      buf[7] = inner_url.fragment_start.unwrap_or(0);
+      let serialization: String = url.into();
+      if serialization != href {
+        state.put(UrlSerialization(serialization));
+        ParseStatus::OkSerialization as u32
+      } else {
+        ParseStatus::Ok as u32
+      }
+    }
+    Err(_) => ParseStatus::Err as u32,
+  }
 }
 
 #[derive(PartialEq, Debug)]
@@ -86,58 +142,86 @@ pub enum UrlSetter {
   Username = 8,
 }
 
+const NO_PORT: u32 = 65536;
+
+fn as_u32_slice(slice: &mut [u8]) -> &mut [u32] {
+  assert_eq!(slice.len() % std::mem::size_of::<u32>(), 0);
+  // SAFETY: size is multiple of 4
+  unsafe {
+    std::slice::from_raw_parts_mut(
+      slice.as_mut_ptr() as *mut u32,
+      slice.len() / std::mem::size_of::<u32>(),
+    )
+  }
+}
+
 #[op]
 pub fn op_url_reparse(
+  state: &mut OpState,
   href: String,
-  setter_opts: (u8, String),
-) -> Result<UrlParts, AnyError> {
-  let mut url = Url::options()
-    .parse(&href)
-    .map_err(|_| type_error("Invalid URL"))?;
+  setter: u8,
+  setter_value: String,
+  buf: &mut [u8],
+) -> u32 {
+  let mut url = match Url::options().parse(&href) {
+    Ok(url) => url,
+    Err(_) => return ParseStatus::Err as u32,
+  };
 
-  let (setter, setter_value) = setter_opts;
   if setter > 8 {
-    return Err(type_error("Invalid URL setter"));
+    return ParseStatus::Err as u32;
   }
   // SAFETY: checked to be less than 9.
   let setter = unsafe { std::mem::transmute::<u8, UrlSetter>(setter) };
   let value = setter_value.as_ref();
-  match setter {
-    UrlSetter::Hash => quirks::set_hash(&mut url, value),
-    UrlSetter::Host => quirks::set_host(&mut url, value)
-      .map_err(|_| uri_error("Invalid host"))?,
-    UrlSetter::Hostname => quirks::set_hostname(&mut url, value)
-      .map_err(|_| uri_error("Invalid hostname"))?,
-    UrlSetter::Password => quirks::set_password(&mut url, value)
-      .map_err(|_| uri_error("Invalid password"))?,
-    UrlSetter::Pathname => quirks::set_pathname(&mut url, value),
-    UrlSetter::Port => quirks::set_port(&mut url, value)
-      .map_err(|_| uri_error("Invalid port"))?,
-    UrlSetter::Protocol => quirks::set_protocol(&mut url, value)
-      .map_err(|_| uri_error("Invalid protocol"))?,
-    UrlSetter::Search => quirks::set_search(&mut url, value),
-    UrlSetter::Username => quirks::set_username(&mut url, value)
-      .map_err(|_| uri_error("Invalid username"))?,
-  }
+  let e = match setter {
+    UrlSetter::Hash => {
+      quirks::set_hash(&mut url, value);
+      Ok(())
+    }
+    UrlSetter::Host => quirks::set_host(&mut url, value),
 
-  Ok(url_parts(url))
-}
+    UrlSetter::Hostname => quirks::set_hostname(&mut url, value),
+
+    UrlSetter::Password => quirks::set_password(&mut url, value),
 
-fn url_parts(url: Url) -> UrlParts {
-  [
-    quirks::href(&url),
-    quirks::hash(&url),
-    quirks::host(&url),
-    quirks::hostname(&url),
-    &quirks::origin(&url),
-    quirks::password(&url),
-    quirks::pathname(&url),
-    quirks::port(&url),
-    quirks::protocol(&url),
-    quirks::search(&url),
-    quirks::username(&url),
-  ]
-  .join("\n")
+    UrlSetter::Pathname => {
+      quirks::set_pathname(&mut url, value);
+      Ok(())
+    }
+    UrlSetter::Port => quirks::set_port(&mut url, value),
+
+    UrlSetter::Protocol => quirks::set_protocol(&mut url, value),
+    UrlSetter::Search => {
+      quirks::set_search(&mut url, value);
+      Ok(())
+    }
+    UrlSetter::Username => quirks::set_username(&mut url, value),
+  };
+
+  match e {
+    Ok(_) => {
+      let inner_url = quirks::internal_components(&url);
+
+      let buf: &mut [u32] = as_u32_slice(buf);
+      buf[0] = inner_url.scheme_end;
+      buf[1] = inner_url.username_end;
+      buf[2] = inner_url.host_start;
+      buf[3] = inner_url.host_end;
+      buf[4] = inner_url.port.map(|p| p as u32).unwrap_or(NO_PORT);
+      buf[5] = inner_url.path_start;
+      buf[6] = inner_url.query_start.unwrap_or(0);
+      buf[7] = inner_url.fragment_start.unwrap_or(0);
+      let serialization: String = url.into();
+      if serialization != href {
+        state.put(UrlSerialization(serialization));
+        ParseStatus::OkSerialization as u32
+      } else {
+        ParseStatus::Ok as u32
+      }
+    }
+    Err(_) => ParseStatus::Err as u32,
+  }
 }
 
 #[op]