introduce a new method (set_host_to_base_host) to replace set_host when set_host is unnecessary

include/ada/url_aggregator-inl.h

@@ -1109,6 +1109,28 @@ inline std::ostream &operator<<(std::ostream &out,
                                 const ada::url_aggregator &u) {
   return out << u.to_string();
 }
+
+void url_aggregator::update_host_to_base_host(
+    const std::string_view input) noexcept {
+  ada_log("url_aggregator::update_host_to_base_host ", input);
+  ADA_ASSERT_TRUE(validate());
+  ADA_ASSERT_TRUE(!helpers::overlaps(input, buffer));
+  if (type != ada::scheme::type::FILE) {
+    // Let host be the result of host parsing host_view with url is not special.
+    if (input.empty() && !is_special()) {
+      if (has_hostname()) {
+        clear_hostname();
+      } else if (has_dash_dot()) {
+        add_authority_slashes_if_needed();
+        delete_dash_dot();
+      }
+      return;
+    }
+  }
+  update_base_hostname(input);
+  ADA_ASSERT_TRUE(validate());
+  return;
+}
 }  // namespace ada
 
 #endif  // ADA_URL_AGGREGATOR_INL_H

include/ada/url_aggregator.h

@@ -313,6 +313,8 @@ struct url_aggregator : url_base {
       std::string_view new_scheme_with_colon) noexcept;
   inline void copy_scheme(const url_aggregator &u) noexcept;
 
+  inline void update_host_to_base_host(const std::string_view input) noexcept;
+
 };  // url_aggregator
 
 inline std::ostream &operator<<(std::ostream &out, const ada::url &u);

src/parser.cpp

@@ -427,9 +427,7 @@ result_type parse_url_impl(std::string_view user_input,
           } else {
             url.update_base_authority(base_url->get_href(),
                                       base_url->get_components());
-            // TODO: Get rid of set_hostname and replace it with
-            // update_base_hostname
-            url.set_hostname(base_url->get_hostname());
+            url.update_host_to_base_host(base_url->get_hostname());
             url.update_base_port(base_url->retrieve_base_port());
             // cloning the base path includes cloning the has_opaque_path flag
             url.has_opaque_path = base_url->has_opaque_path;
@@ -497,9 +495,7 @@ result_type parse_url_impl(std::string_view user_input,
           } else {
             url.update_base_authority(base_url->get_href(),
                                       base_url->get_components());
-            // TODO: Get rid of set_hostname and replace it with
-            // update_base_hostname
-            url.set_hostname(base_url->get_hostname());
+            url.update_host_to_base_host(base_url->get_hostname());
             url.update_base_port(base_url->retrieve_base_port());
           }
           state = ada::state::PATH;
@@ -736,8 +732,7 @@ result_type parse_url_impl(std::string_view user_input,
             if constexpr (result_type_is_ada_url) {
               url.host = base_url->host;
             } else {
-              // TODO: Optimization opportunity.
-              url.set_host(base_url->get_host());
+              url.update_host_to_base_host(base_url->get_host());
             }
             // If the code point substring from pointer to the end of input does
             // not start with a Windows drive letter and base's path[0] is a
@@ -848,9 +843,7 @@ result_type parse_url_impl(std::string_view user_input,
             url.path = base_url->path;
             url.query = base_url->query;
           } else {
-            // TODO: Get rid of set_hostname and replace it with
-            // update_base_hostname
-            url.set_hostname(base_url->get_hostname());
+            url.update_host_to_base_host(base_url->get_hostname());
             url.update_base_pathname(base_url->get_pathname());
             url.update_base_search(base_url->get_search());
           }