AK: Serialize URL hosts with 'concept-host-serializer'

In order to follow spec text to achieve this, we need to change the
underlying representation of a host in AK::URL to deserialized format.
Before this, we were parsing the host and then immediately serializing
it again.

Making that change resulted in a whole bunch of fallout.

After this change, callers can access the serialized data through
this concept-host-serializer. The functional end result of this
change is that IPv6 hosts are now correctly serialized to be
surrounded with '[' and ']'.

Userland/Libraries/LibWeb/HTML/BrowsingContext.cpp

@@ -44,7 +44,7 @@ static bool url_matches_about_blank(AK::URL const& url)
         && url.serialize_path() == "blank"sv
         && url.username().is_empty()
         && url.password().is_empty()
-        && url.host().is_null();
+        && url.host().has<Empty>();
 }
 
 // FIXME: This is an outdated older version of "determining the origin" and should be removed.

Userland/Libraries/LibWeb/HTML/HTMLHyperlinkElementUtils.cpp

@@ -167,15 +167,15 @@ DeprecatedString HTMLHyperlinkElementUtils::host() const
     auto& url = m_url;
 
     // 3. If url or url's host is null, return the empty string.
-    if (!url.has_value() || url->host().is_null())
+    if (!url.has_value() || url->host().has<Empty>())
         return DeprecatedString::empty();
 
     // 4. If url's port is null, return url's host, serialized.
     if (!url->port().has_value())
-        return url->host();
+        return url->serialized_host().release_value_but_fixme_should_propagate_errors().to_deprecated_string();
 
     // 5. Return url's host, serialized, followed by ":" and url's port, serialized.
-    return DeprecatedString::formatted("{}:{}", url->host(), url->port().value());
+    return DeprecatedString::formatted("{}:{}", url->serialized_host().release_value_but_fixme_should_propagate_errors(), url->port().value());
 }
 
 // https://html.spec.whatwg.org/multipage/links.html#dom-hyperlink-host
@@ -205,11 +205,14 @@ DeprecatedString HTMLHyperlinkElementUtils::hostname() const
     // 1. Reinitialize url.
     //
     // 2. Let url be this element's url.
-    //
+    AK::URL url(href());
+
     // 3. If url or url's host is null, return the empty string.
-    //
+    if (url.host().has<Empty>())
+        return DeprecatedString::empty();
+
     // 4. Return url's host, serialized.
-    return AK::URL(href()).host();
+    return url.serialized_host().release_value_but_fixme_should_propagate_errors().to_deprecated_string();
 }
 
 void HTMLHyperlinkElementUtils::set_hostname(DeprecatedString hostname)

Userland/Libraries/LibWeb/HTML/Location.cpp

@@ -153,15 +153,15 @@ WebIDL::ExceptionOr<String> Location::host() const
     auto url = this->url();
 
     // 3. If url's host is null, return the empty string.
-    if (url.host().is_null())
+    if (url.host().has<Empty>())
         return String {};
 
     // 4. If url's port is null, return url's host, serialized.
     if (!url.port().has_value())
-        return TRY_OR_THROW_OOM(vm, String::from_deprecated_string(url.host()));
+        return TRY_OR_THROW_OOM(vm, url.serialized_host());
 
     // 5. Return url's host, serialized, followed by ":" and url's port, serialized.
-    return TRY_OR_THROW_OOM(vm, String::formatted("{}:{}", url.host(), *url.port()));
+    return TRY_OR_THROW_OOM(vm, String::formatted("{}:{}", TRY_OR_THROW_OOM(vm, url.serialized_host()), *url.port()));
 }
 
 WebIDL::ExceptionOr<void> Location::set_host(String const&)
@@ -183,11 +183,11 @@ WebIDL::ExceptionOr<String> Location::hostname() const
     auto url = this->url();
 
     // 2. If this's url's host is null, return the empty string.
-    if (url.host().is_null())
+    if (url.host().has<Empty>())
         return String {};
 
     // 3. Return this's url's host, serialized.
-    return TRY_OR_THROW_OOM(vm, String::from_deprecated_string(url.host()));
+    return TRY_OR_THROW_OOM(vm, url.serialized_host());
 }
 
 WebIDL::ExceptionOr<void> Location::set_hostname(String const&)

Userland/Libraries/LibWeb/HTML/NavigableContainer.cpp

@@ -217,7 +217,7 @@ static bool url_matches_about_blank(AK::URL const& url)
         && url.serialize_path() == "blank"sv
         && url.username().is_empty()
         && url.password().is_empty()
-        && url.host().is_null();
+        && url.host().has<Empty>();
 }
 
 // https://html.spec.whatwg.org/multipage/iframe-embed-object.html#shared-attribute-processing-steps-for-iframe-and-frame-elements

Userland/Libraries/LibWeb/HTML/Origin.h

@@ -8,13 +8,15 @@
 #pragma once
 
 #include <AK/DeprecatedString.h>
+#include <AK/URL.h>
+#include <AK/URLParser.h>
 
 namespace Web::HTML {
 
 class Origin {
 public:
     Origin() = default;
-    Origin(DeprecatedString const& scheme, DeprecatedString const& host, u16 port)
+    Origin(DeprecatedString const& scheme, AK::URL::Host const& host, u16 port)
         : m_scheme(scheme)
         , m_host(host)
         , m_port(port)
@@ -22,10 +24,10 @@ public:
     }
 
     // https://html.spec.whatwg.org/multipage/origin.html#concept-origin-opaque
-    bool is_opaque() const { return m_scheme.is_null() && m_host.is_null() && m_port == 0; }
+    bool is_opaque() const { return m_scheme.is_null() && m_host.has<Empty>() && m_port == 0; }
 
     DeprecatedString const& scheme() const { return m_scheme; }
-    DeprecatedString const& host() const { return m_host; }
+    AK::URL::Host const& host() const { return m_host; }
     u16 port() const { return m_port; }
 
     // https://html.spec.whatwg.org/multipage/origin.html#same-origin
@@ -81,7 +83,7 @@ public:
         result.append("://"sv);
 
         // 4. Append origin's host, serialized, to result.
-        result.append(host());
+        result.append(URLParser::serialize_host(host()).release_value_but_fixme_should_propagate_errors().to_deprecated_string());
 
         // 5. If origin's port is non-null, append a U+003A COLON character (:), and origin's port, serialized, to result.
         if (port() != 0) {
@@ -93,11 +95,11 @@ public:
     }
 
     // https://html.spec.whatwg.org/multipage/origin.html#concept-origin-effective-domain
-    Optional<DeprecatedString> effective_domain() const
+    Optional<AK::URL::Host> effective_domain() const
     {
         // 1. If origin is an opaque origin, then return null.
         if (is_opaque())
-            return Optional<DeprecatedString> {};
+            return {};
 
         // FIXME: 2. If origin's domain is non-null, then return origin's domain.
 
@@ -109,7 +111,7 @@ public:
 
 private:
     DeprecatedString m_scheme;
-    DeprecatedString m_host;
+    AK::URL::Host m_host;
     u16 m_port { 0 };
 };
 
@@ -120,7 +122,10 @@ template<>
 struct Traits<Web::HTML::Origin> : public GenericTraits<Web::HTML::Origin> {
     static unsigned hash(Web::HTML::Origin const& origin)
     {
-        return pair_int_hash(origin.scheme().hash(), pair_int_hash(int_hash(origin.port()), origin.host().hash()));
+        auto hash_without_host = pair_int_hash(origin.scheme().hash(), origin.port());
+        if (origin.host().has<Empty>())
+            return hash_without_host;
+        return pair_int_hash(hash_without_host, URLParser::serialize_host(origin.host()).release_value_but_fixme_should_propagate_errors().hash());
     }
 };
 } // namespace AK

Userland/Libraries/LibWeb/HTML/WorkerLocation.cpp

@@ -4,6 +4,7 @@
  * SPDX-License-Identifier: BSD-2-Clause
  */
 
+#include <AK/URLParser.h>
 #include <LibWeb/HTML/WorkerGlobalScope.h>
 #include <LibWeb/HTML/WorkerLocation.h>
 
@@ -43,15 +44,15 @@ WebIDL::ExceptionOr<String> WorkerLocation::host() const
     auto const& url = m_global_scope->url();
 
     // 2. If url's host is null, return the empty string.
-    if (url.host().is_empty())
+    if (url.host().has<Empty>())
         return String {};
 
     // 3. If url's port is null, return url's host, serialized.
     if (!url.port().has_value())
-        return TRY_OR_THROW_OOM(vm, String::from_deprecated_string(url.host()));
+        return TRY_OR_THROW_OOM(vm, url.serialized_host());
 
     // 4. Return url's host, serialized, followed by ":" and url's port, serialized.
-    return TRY_OR_THROW_OOM(vm, String::formatted("{}:{}", url.host().view(), url.port().value()));
+    return TRY_OR_THROW_OOM(vm, String::formatted("{}:{}", TRY_OR_THROW_OOM(vm, url.serialized_host()), url.port().value()));
 }
 
 // https://html.spec.whatwg.org/multipage/workers.html#dom-workerlocation-hostname
@@ -64,11 +65,11 @@ WebIDL::ExceptionOr<String> WorkerLocation::hostname() const
     auto const& host = m_global_scope->url().host();
 
     // 2. If host is null, return the empty string.
-    if (host.is_empty())
+    if (host.has<Empty>())
         return String {};
 
     // 3. Return host, serialized.
-    return TRY_OR_THROW_OOM(vm, String::from_deprecated_string(host));
+    return TRY_OR_THROW_OOM(vm, URLParser::serialize_host(host));
 }
 
 // https://html.spec.whatwg.org/multipage/workers.html#dom-workerlocation-port