http: normalize CONNECT request paths

lib/_http_client.js

@@ -28,6 +28,7 @@ const {
   NumberIsFinite,
   ObjectAssign,
   ObjectDefineProperty,
+  ObjectHasOwn,
   ObjectKeys,
   ObjectSetPrototypeOf,
   ReflectApply,
@@ -331,12 +332,15 @@ function rewriteForProxiedHttp(req, reqOptions, proxyAuthority, userHostHeader,
 function ClientRequest(input, options, cb) {
   OutgoingMessage.call(this);
 
+  let pathIsFromURL = false;
   if (typeof input === 'string') {
     const urlStr = input;
     input = urlToHttpOptions(new URL(urlStr));
+    pathIsFromURL = true;
   } else if (isURL(input)) {
     // url.URL instance
     input = urlToHttpOptions(input);
+    pathIsFromURL = true;
   } else {
     cb = options;
     options = input;
@@ -347,6 +351,13 @@ function ClientRequest(input, options, cb) {
     cb = options;
     options = input || kEmptyObject;
   } else {
+    const hasPathOverride = pathIsFromURL &&
+      options != null &&
+      ObjectHasOwn(options, 'path');
+    if (hasPathOverride) {
+      pathIsFromURL = false;
+    }
+
     options = ObjectAssign({ __proto__: null }, input, options);
   }
 
@@ -466,7 +477,13 @@ function ClientRequest(input, options, cb) {
 
   this.joinDuplicateHeaders = options.joinDuplicateHeaders;
 
-  this[kPath] = options.path || '/';
+  let path = options.path || '/';
+  // Strip the leading slash added when the CONNECT target comes from a URL.
+  if (method === 'CONNECT' && pathIsFromURL && path[0] === '/') {
+    path = path.slice(1) || '/';
+  }
+
+  this[kPath] = path;
   if (cb) {
     this.once('response', cb);
   }

test/parallel/test-http-request-connect-path.js

@@ -0,0 +1,56 @@
+'use strict';
+
+const common = require('../common');
+const assert = require('assert');
+const http = require('http');
+
+{
+  const server = http.createServer(common.mustNotCall());
+
+  server.on('connect', common.mustCall((req, socket) => {
+    assert.strictEqual(req.url, 'example.com');
+    socket.end('HTTP/1.1 501 Not Implemented\r\n\r\n');
+  }));
+
+  server.listen(0, common.mustCall(() => {
+    const port = server.address().port;
+    const req = http.request(
+      new URL(`http://localhost:${port}/example.com`),
+      { method: 'CONNECT' },
+    );
+
+    req.on('connect', common.mustCall((res, socket) => {
+      assert.strictEqual(res.statusCode, 501);
+      socket.destroy();
+      server.close();
+    }));
+
+    req.end();
+  }));
+}
+
+{
+  const server = http.createServer(common.mustNotCall());
+
+  server.on('connect', common.mustCall((req, socket) => {
+    assert.strictEqual(req.url, '/example.com');
+    socket.end('HTTP/1.1 501 Not Implemented\r\n\r\n');
+  }));
+
+  server.listen(0, common.mustCall(() => {
+    const req = http.request({
+      host: 'localhost',
+      port: server.address().port,
+      method: 'CONNECT',
+      path: '/example.com',
+    });
+
+    req.on('connect', common.mustCall((res, socket) => {
+      assert.strictEqual(res.statusCode, 501);
+      socket.destroy();
+      server.close();
+    }));
+
+    req.end();
+  }));
+}