feat!: change default --host to 127.0.0.1

Node.js v17 changed its DNS resolution defaults, and it can cause
localhost to resolve to IPv6 instead of IPv4. Inspector, on the other
hand, responds only to 127.0.0.1 by default. So changing the default for
--host to 127.0.0.1 seems appropriate. Marking as breaking in case
anyone is relying on `localhost` resolving to IPv6 on newer Node.js
versions.

bin/common.js

@@ -24,7 +24,7 @@ function getHostPortFromArgs({ pid, host, port }) {
     startDebugger(pid);
   }
 
-  return { host: host || 'localhost', port: port || 9229 };
+  return { host: host || '127.0.0.1', port: port || 9229 };
 }
 
 function getStreamFromArgs({ file }) {

test/common.js

@@ -173,7 +173,7 @@ class FakeStream {
 async function runCommandWithClient(run, port, ...args) {
   const stream = new FakeStream();
 
-  const client = new Client('localhost', port);
+  const client = new Client('127.0.0.1', port);
   await client.connect();
 
   await run(client, stream, ...args);

test/test-inspector-client.js

@@ -10,7 +10,7 @@ test('attach to existing process', (t) => {
   f.on('inspectorReady', async ({ port }) => {
     t.ok(port > 0);
 
-    const client = new Client('localhost', port);
+    const client = new Client('127.0.0.1', port);
     try {
       await client.connect();
       await client.disconnect();
@@ -27,7 +27,7 @@ test('send message', (t) => {
   f.on('inspectorReady', async ({ port }) => {
     t.ok(port > 0);
 
-    const client = new Client('localhost', port);
+    const client = new Client('127.0.0.1', port);
     try {
       await client.connect();
       t.deepEqual(await client.post('Profiler.enable'), {});
@@ -46,7 +46,7 @@ test('receive message', (t) => {
   f.on('inspectorReady', async ({ port }) => {
     t.ok(port > 0);
 
-    const client = new Client('localhost', port);
+    const client = new Client('127.0.0.1', port);
     try {
       await client.connect();
       await client.post('Debugger.enable', {});