url: run setter steps after converting the value

lib/internal/url.js

@@ -1065,7 +1065,9 @@ class URL {
   }
 
   set protocol(value) {
-    const href = bindingUrl.update(this.#context.href, updateActions.kProtocol, `${value}`);
+    const context = this.#context;
+    value = `${value}`;
+    const href = bindingUrl.update(context.href, updateActions.kProtocol, value);
     if (href) {
       this.#updateContext(href);
     }
@@ -1079,7 +1081,9 @@ class URL {
   }
 
   set username(value) {
-    const href = bindingUrl.update(this.#context.href, updateActions.kUsername, `${value}`);
+    const context = this.#context;
+    value = `${value}`;
+    const href = bindingUrl.update(context.href, updateActions.kUsername, value);
     if (href) {
       this.#updateContext(href);
     }
@@ -1093,7 +1097,9 @@ class URL {
   }
 
   set password(value) {
-    const href = bindingUrl.update(this.#context.href, updateActions.kPassword, `${value}`);
+    const context = this.#context;
+    value = `${value}`;
+    const href = bindingUrl.update(context.href, updateActions.kPassword, value);
     if (href) {
       this.#updateContext(href);
     }
@@ -1113,7 +1119,9 @@ class URL {
   }
 
   set host(value) {
-    const href = bindingUrl.update(this.#context.href, updateActions.kHost, `${value}`);
+    const context = this.#context;
+    value = `${value}`;
+    const href = bindingUrl.update(context.href, updateActions.kHost, value);
     if (href) {
       this.#updateContext(href);
     }
@@ -1129,7 +1137,9 @@ class URL {
   }
 
   set hostname(value) {
-    const href = bindingUrl.update(this.#context.href, updateActions.kHostname, `${value}`);
+    const context = this.#context;
+    value = `${value}`;
+    const href = bindingUrl.update(context.href, updateActions.kHostname, value);
     if (href) {
       this.#updateContext(href);
     }
@@ -1143,7 +1153,9 @@ class URL {
   }
 
   set port(value) {
-    const href = bindingUrl.update(this.#context.href, updateActions.kPort, `${value}`);
+    const context = this.#context;
+    value = `${value}`;
+    const href = bindingUrl.update(context.href, updateActions.kPort, value);
     if (href) {
       this.#updateContext(href);
     }
@@ -1160,7 +1172,9 @@ class URL {
   }
 
   set pathname(value) {
-    const href = bindingUrl.update(this.#context.href, updateActions.kPathname, `${value}`);
+    const context = this.#context;
+    value = `${value}`;
+    const href = bindingUrl.update(context.href, updateActions.kPathname, value);
     if (href) {
       this.#updateContext(href);
     }
@@ -1173,7 +1187,9 @@ class URL {
   }
 
   set search(value) {
-    const href = bindingUrl.update(this.#context.href, updateActions.kSearch, StringPrototypeToWellFormed(`${value}`));
+    const context = this.#context;
+    value = StringPrototypeToWellFormed(`${value}`);
+    const href = bindingUrl.update(context.href, updateActions.kSearch, value);
     if (href) {
       this.#updateContext(href, true);
     }
@@ -1198,7 +1214,9 @@ class URL {
   }
 
   set hash(value) {
-    const href = bindingUrl.update(this.#context.href, updateActions.kHash, `${value}`);
+    const context = this.#context;
+    value = `${value}`;
+    const href = bindingUrl.update(context.href, updateActions.kHash, value);
     if (href) {
       this.#updateContext(href);
     }

test/parallel/test-whatwg-url-custom-setters-conversion.js

@@ -0,0 +1,76 @@
+'use strict';
+
+// Tests below are not from WPT.
+
+require('../common');
+const assert = require('assert');
+
+// Web IDL converts the assigned value to a string before the setter steps
+// run, so the steps must see a URL that the conversion itself changed.
+// Refs: https://github.com/nodejs/node/issues/67345
+const setters = {
+  protocol: ['http:', 'http://after.example/base'],
+  username: ['user', 'https://user@after.example/base'],
+  password: ['pass', 'https://:pass@after.example/base'],
+  host: ['other.example:8080', 'https://other.example:8080/base'],
+  hostname: ['other.example', 'https://other.example/base'],
+  port: ['8080', 'https://after.example:8080/base'],
+  pathname: ['/new', 'https://after.example/new'],
+  search: ['?q=1', 'https://after.example/base?q=1'],
+  hash: ['#frag', 'https://after.example/base#frag'],
+};
+
+for (const [name, [value, expected]] of Object.entries(setters)) {
+  const url = new URL('https://before.example/old');
+  url[name] = {
+    toString() {
+      url.href = 'https://after.example/base';
+      return value;
+    },
+  };
+  assert.strictEqual(url.href, expected, `URL.prototype.${name} setter`);
+}
+
+// A URL with an opaque path has no host to set, even when it only became
+// one while the value was converted.
+{
+  const url = new URL('https://before.example/old');
+  url.host = {
+    toString() {
+      url.href = 'mailto:someone@after.example';
+      return 'other.example';
+    },
+  };
+  assert.strictEqual(url.href, 'mailto:someone@after.example');
+}
+
+// The search params follow the URL the setter steps saw.
+{
+  const url = new URL('https://before.example/old?a=1');
+  const { searchParams } = url;
+  url.search = {
+    toString() {
+      url.href = 'https://after.example/base?b=2';
+      return '?c=3';
+    },
+  };
+  assert.strictEqual(url.href, 'https://after.example/base?c=3');
+  assert.strictEqual(searchParams.toString(), 'c=3');
+}
+
+// The receiver is checked before the value is converted.
+for (const name of Object.keys(setters)) {
+  const { set } = Object.getOwnPropertyDescriptor(URL.prototype, name);
+  let conversions = 0;
+  assert.throws(() => {
+    set.call({}, {
+      toString() {
+        conversions++;
+        return '';
+      },
+    });
+  }, {
+    name: 'TypeError',
+  });
+  assert.strictEqual(conversions, 0, `URL.prototype.${name} setter`);
+}