src,test: debug is now an alias for inspect

`node debug` is now an alias of `node inspect`. This is intended to be
a minimal change – it does not get rid of the the debugger code. That
can be done in a follow-on.

PR-URL: https://github.com/nodejs/node/pull/11441
Reviewed-By: bnoordhuis - Ben Noordhuis <info@bnoordhuis.nl>
Reviewed-By: joshgav - Josh Gavant <josh.gavant@outlook.com>
Reviewed-By: cjihrig - Colin Ihrig <cjihrig@gmail.com>
Reviewed-By: targos - Michaël Zasso <mic.besace@gmail.com>

doc/api/deprecations.md

@@ -582,6 +582,14 @@ deprecated.
 *Note*: `OutgoingMessage.prototype._renderHeaders` was never documented as
 an officially supported API.
 
+<a id="DEP0068"></a>
+### DEP0068: node debug
+
+Type: Runtime
+
+`node debug` corresponds to the legacy CLI debugger which has been replaced with
+a V8-inspector based CLI debugger available through `node inspect`.
+
 [alloc]: buffer.html#buffer_class_method_buffer_alloc_size_fill_encoding
 [alloc_unsafe_size]: buffer.html#buffer_class_method_buffer_allocunsafe_size
 [`Buffer.allocUnsafeSlow(size)`]: buffer.html#buffer_class_method_buffer_allocunsafeslow_size

lib/internal/bootstrap_node.js

@@ -78,11 +78,13 @@
         NativeModule.require('_third_party_main');
       });
 
-    } else if (process.argv[1] === 'debug') {
-      // Start the debugger agent
-      NativeModule.require('_debugger').start();
+    } else if (process.argv[1] === 'inspect' || process.argv[1] === 'debug') {
+      if (process.argv[1] === 'debug') {
+        process.emitWarning(
+          '`node debug` is deprecated. Please use `node inspect` instead.',
+          'DeprecationWarning', 'DEP0068');
+      }
 
-    } else if (process.argv[1] === 'inspect') {
       // Start the debugger agent
       process.nextTick(function() {
         NativeModule.require('node-inspect/lib/_inspect').start();

src/inspector_socket_server.cc

@@ -82,10 +82,10 @@ void PrintDebuggerReadyMessage(const std::string& host,
     return;
   }
   fprintf(out,
-          "Debugger listening on port %d.\n"
+          "Debugger listening on %s:%d.\n"
           "Warning: This is an experimental feature "
           "and could change at any time.\n",
-          port);
+          host.c_str(), port);
   if (ids.size() == 1)
     fprintf(out, "To start debugging, open the following URL in Chrome:\n");
   if (ids.size() > 1)

src/node.cc

@@ -3525,7 +3525,7 @@ static void PrintHelp() {
   // XXX: If you add an option here, please also add it to doc/node.1 and
   // doc/api/cli.md
   printf("Usage: node [options] [ -e script | script.js ] [arguments]\n"
-         "       node debug script.js [arguments]\n"
+         "       node inspect script.js [arguments]\n"
          "\n"
          "Options:\n"
          "  -v, --version              print Node.js version\n"

test/inspector/inspector-helper.js

@@ -461,7 +461,7 @@ exports.startNodeForInspectorTest = function(callback,
     clearTimeout(timeoutId);
     console.log('[err]', text);
     if (found) return;
-    const match = text.match(/Debugger listening on port (\d+)/);
+    const match = text.match(/Debugger listening on .*:(\d+)/);
     found = true;
     child.stderr.removeListener('data', dataCallback);
     assert.ok(match, text);

test/parallel/test-debug-usage.js

@@ -6,16 +6,20 @@ const spawn = require('child_process').spawn;
 const child = spawn(process.execPath, ['debug']);
 child.stderr.setEncoding('utf8');
 
-const expectedUsageMessage = `Usage: node debug script.js
-       node debug <host>:<port>
-       node debug -p <pid>
-`;
+const expectedLines = [
+  /^\(node:\d+\) \[DEP0068\] DeprecationWarning:/,
+  /^Usage: .*node.* debug script\.js$/,
+  /^       .*node.* debug <host>:<port>$/
+];
+
 let actualUsageMessage = '';
 child.stderr.on('data', function(data) {
   actualUsageMessage += data.toString();
 });
 
 child.on('exit', common.mustCall(function(code) {
+  const outputLines = actualUsageMessage.split('\n');
   assert.strictEqual(code, 1);
-  assert.strictEqual(actualUsageMessage, expectedUsageMessage);
+  for (let i = 0; i < expectedLines.length; i++)
+    assert(expectedLines[i].test(outputLines[i]));
 }));

test/parallel/test-debugger-repeat-last.js

@@ -20,20 +20,22 @@ proc.stdout.setEncoding('utf8');
 let stdout = '';
 
 let sentCommand = false;
-let sentEmpty = false;
 let sentExit = false;
 
 proc.stdout.on('data', (data) => {
   stdout += data;
-  if (!sentCommand && stdout.includes('> 1')) {
+
+  // Send 'n' as the first step.
+  if (!sentCommand && stdout.includes('> 1 ')) {
     setImmediate(() => { proc.stdin.write('n\n'); });
     return sentCommand = true;
   }
-  if (!sentEmpty && stdout.includes('> 3')) {
+  // Send empty (repeat last command) until we reach line 5.
+  if (sentCommand && !stdout.includes('> 5')) {
     setImmediate(() => { proc.stdin.write('\n'); });
-    return sentEmpty = true;
+    return true;
   }
-  if (!sentExit && sentCommand && sentEmpty) {
+  if (!sentExit && stdout.includes('> 5')) {
     setTimeout(() => { proc.stdin.write('\n\n\n.exit\n\n\n'); }, 1);
     return sentExit = true;
   }