url: reject empty host after toAscii conversion

Per the change in whatwg/url#497.

Author: djc

src/host.rs

@@ -82,6 +82,9 @@ impl Host<String> {
         }
         let domain = percent_decode(input.as_bytes()).decode_utf8_lossy();
         let domain = idna::domain_to_ascii(&domain)?;
+        if domain.is_empty() {
+            return Err(ParseError::EmptyHost);
+        }
         if domain
             .find(|c| {
                 matches!(

tests/setters_tests.json

@@ -950,16 +950,6 @@
                 "port": ""
             }
         },
-        {
-            "href": "file://hi/x",
-            "new_value": "",
-            "expected": {
-                "href": "file:///x",
-                "host": "",
-                "hostname": "",
-                "port": ""
-            }
-        },
         {
             "href": "sc://test@test/",
             "new_value": "",
@@ -1284,16 +1274,6 @@
                 "port": ""
             }
         },
-        {
-            "href": "file://hi/x",
-            "new_value": "",
-            "expected": {
-                "href": "file:///x",
-                "host": "",
-                "hostname": "",
-                "port": ""
-            }
-        },
         {
             "href": "sc://test@test/",
             "new_value": "",