lib: deprecate node --debug at runtime

Fixes: #9789
PR-URL: #10970
Reviewed-By: James M Snell <jasnell@gmail.com>
Reviewed-By: Evan Lucas <evanlucas@me.com>
Reviewed-By: Ali Ijaz Sheikh <ofrobots@google.com>
Reviewed-By: Rich Trott <rtrott@gmail.com>

Author: joshgav

doc/api/deprecations.md

@@ -511,6 +511,15 @@ Type: Documentation-only
 The `fs.SyncWriteStream` class was never intended to be a publicly accessible
 API.
 
+<aid="DEP0062"></a>
+### DEP0062: node --debug
+
+Type: Runtime
+
+`--debug` activates the legacy V8 debugger interface, which has been removed as
+of V8 5.8. It is replaced by Inspector which is activated with `--inspect`
+instead.
+
 [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/_debug_agent.js

@@ -1,5 +1,10 @@
 'use strict';
 
+process.emitWarning(
+'node --debug is deprecated. Please use node --inspect instead.',
+'DeprecationWarning',
+'DEP0062');
+
 constassert=require('assert');
 constnet=require('net');
 constutil=require('util');

test/parallel/test-debug-port-from-cmdline.js

@@ -2,12 +2,19 @@
 constcommon=require('../common');
 constassert=require('assert');
 constspawn=require('child_process').spawn;
+constos=require('os');
 
 constdebugPort=common.PORT;
 constargs=['--interactive','--debug-port='+debugPort];
 constchildOptions={stdio: ['pipe','pipe','pipe','ipc']};
 constchild=spawn(process.execPath,args,childOptions);
 
+constreDeprecationWarning=newRegExp(
+/^\(node:\d+\)\[DEP0062\]DeprecationWarning:/.source+
+/node--debugisdeprecated./.source+
+/Pleaseusenode--inspectinstead.$/.source
+);
+
 child.stdin.write("process.send({ msg: 'childready' });\n");
 
 child.stderr.on('data',function(data){
@@ -37,12 +44,20 @@ function processStderrLine(line) {
 }
 
 functionassertOutputLines(){
-constexpectedLines=[
-'Starting debugger agent.',
-'Debugger listening on 127.0.0.1:'+debugPort,
+// need a var so can swap the first two lines in following
+// eslint-disable-next-line no-var
+varexpectedLines=[
+/^Startingdebuggeragent.$/,
+reDeprecationWarning,
+newRegExp(`^Debugger listening on 127.0.0.1:${debugPort}$`)
 ];
 
+if(os.platform()==='win32'){
+expectedLines[1]=expectedLines[0];
+expectedLines[0]=reDeprecationWarning;
+}
+
 assert.strictEqual(outputLines.length,expectedLines.length);
 for(leti=0;i<expectedLines.length;i++)
-assert(expectedLines[i].includes(outputLines[i]));
+assert(expectedLines[i].test(outputLines[i]));
 }

test/parallel/test-debug-signal-cluster.js

@@ -8,7 +8,8 @@ const path = require('path');
 
 constport=common.PORT;
 constserverPath=path.join(common.fixturesDir,'clustered-server','app.js');
-constargs=[`--debug-port=${port}`,serverPath];
+// cannot use 'Flags: --no-deprecation' since it doesn't effect child
+constargs=[`--debug-port=${port}`,'--no-deprecation',serverPath];
 constoptions={stdio: ['inherit','inherit','pipe','ipc']};
 constchild=spawn(process.execPath,args,options);