url: implement URL.canParse

benchmark/url/whatwgurl-canParse.js

@@ -0,0 +1,14 @@
+'use strict';
+const common = require('../common.js');
+
+const bench = common.createBenchmark(main, {
+  type: Object.keys(common.urls),
+  n: [25e6],
+});
+
+function main({ type, n }) {
+  bench.start();
+  for (let i = 0; i < n; i += 1)
+    URL.canParse(common.urls[type]);
+  bench.end(n);
+}

doc/api/url.md

@@ -662,6 +662,27 @@ added: v16.7.0
 Removes the stored {Blob} identified by the given ID. Attempting to revoke a
 ID that isn't registered will silently fail.
 
+#### `URL.canParse(input[, base])`
+
+<!-- YAML
+added: REPLACEME
+-->
+
+* `input` {string} The absolute or relative input URL to parse. If `input`
+  is relative, then `base` is required. If `input` is absolute, the `base`
+  is ignored. If `input` is not a string, it is [converted to a string][] first.
+* `base` {string} The base URL to resolve against if the `input` is not
+  absolute. If `base` is not a string, it is [converted to a string][] first.
+* Returns: {boolean}
+
+Checks if an `input` relative to the `base` can be parsed to a `URL`.
+
+```js
+const isValid = URL.canParse('/foo', 'https://example.org/'); // true
+
+const isNotValid = URL.canParse('/foo'); // false
+```
+
 ### Class: `URLSearchParams`
 
 <!-- YAML

lib/internal/url.js

@@ -88,6 +88,7 @@ const {
   domainToASCII: _domainToASCII,
   domainToUnicode: _domainToUnicode,
   parse,
+  canParse: _canParse,
   updateUrl,
 } = internalBinding('url');
 
@@ -721,7 +722,7 @@ class URL {
       base = `${base}`;
     }
 
-    return parse(url, base, () => {});
+    return _canParse(url, base);
   }
 }
 

src/node_url.cc

@@ -93,6 +93,30 @@ void Parse(const FunctionCallbackInfo<Value>& args) {
   args.GetReturnValue().Set(true);
 }
 
+void CanParse(const FunctionCallbackInfo<Value>& args) {
+  CHECK_GE(args.Length(), 2);
+  CHECK(args[0]->IsString());  // input
+  // args[1] // base url
+
+  Environment* env = Environment::GetCurrent(args);
+  HandleScope handle_scope(env->isolate());
+  Context::Scope context_scope(env->context());
+
+  Utf8Value input(env->isolate(), args[0]);
+  ada::result base;
+  ada::url* base_pointer = nullptr;
+  if (args[1]->IsString()) {
+    base = ada::parse(Utf8Value(env->isolate(), args[1]).ToString());
+    if (!base) {
+      return args.GetReturnValue().Set(false);
+    }
+    base_pointer = &base.value();
+  }
+  ada::result out = ada::parse(input.ToStringView(), base_pointer);
+
+  args.GetReturnValue().Set(out.has_value());
+}
+
 void DomainToASCII(const FunctionCallbackInfo<Value>& args) {
   Environment* env = Environment::GetCurrent(args);
   CHECK_GE(args.Length(), 1);
@@ -284,6 +308,7 @@ void Initialize(Local<Object> target,
                 Local<Context> context,
                 void* priv) {
   SetMethod(context, target, "parse", Parse);
+  SetMethod(context, target, "canParse", CanParse);
   SetMethod(context, target, "updateUrl", UpdateUrl);
   SetMethodNoSideEffect(context, target, "formatUrl", FormatUrl);
 
@@ -294,6 +319,7 @@ void Initialize(Local<Object> target,
 
 void RegisterExternalReferences(ExternalReferenceRegistry* registry) {
   registry->Register(Parse);
+  registry->Register(CanParse);
   registry->Register(UpdateUrl);
   registry->Register(FormatUrl);