src: remove support for --debug

In the 2017-04-05 meeting, the CTC agreed to remove support for the
legacy debugger in 8.0.0. This is the first step in this direction.

Refs: nodejs/CTC#94
PR-URL: nodejs/node#12197
Reviewed-By: Richard Lau <riclau@uk.ibm.com>
Reviewed-By: Ali Ijaz Sheikh <ofrobots@google.com>
Reviewed-By: Anna Henningsen <anna@addaleax.net>
Reviewed-By: Myles Borins <myles.borins@gmail.com>
Reviewed-By: James M Snell <jasnell@gmail.com>
Reviewed-By: Colin Ihrig <cjihrig@gmail.com>
Reviewed-By: Michaël Zasso <targos@protonmail.com>

doc/api/debugger.md

@@ -169,27 +169,8 @@ breakpoint)
 
 ## Advanced Usage
 
-### TCP-based protocol
-
-> Stability: 0 - Deprecated: Use [V8 Inspector Integration][] instead.
-The debug protocol used by the `--debug` flag was removed from V8.
-
-An alternative way of enabling and accessing the debugger is to start
-Node.js with the `--debug` command-line flag or by signaling an existing
-Node.js process with `SIGUSR1`.
-
-Once a process has been set in debug mode this way, it can be inspected
-using the Node.js debugger by either connecting to the `pid` of the running
-process or via URI reference to the listening debugger:
-
-* `node debug -p <pid>` - Connects to the process via the `pid`
-* `node debug <URI>` - Connects to the process via the URI such as
-localhost:5858
-
 ### V8 Inspector Integration for Node.js
 
-**NOTE: This is an experimental feature.**
-
 V8 Inspector integration allows attaching Chrome DevTools to Node.js
 instances for debugging and profiling. It uses the [Chrome Debugging Protocol][].
 

doc/api/process.md

@@ -1757,9 +1757,8 @@ cases:
   source code internal in Node.js's bootstrapping process threw an error
   when the bootstrapping function was called.  This is extremely rare,
   and generally can only happen during development of Node.js itself.
-* `12` **Invalid Debug Argument** - The `--debug`, `--inspect` and/or
-  `--debug-brk` options were set, but the port number chosen was invalid
-  or unavailable.
+* `12` **Invalid Debug Argument** - The `--inspect` and/or `--inspect-brk`
+  options were set, but the port number chosen was invalid or unavailable.
 * `>128` **Signal Exits** - If Node.js receives a fatal signal such as
   `SIGKILL` or `SIGHUP`, then its exit code will be `128` plus the
   value of the signal code.  This is a standard Unix practice, since

src/node_debug_options.cc

@@ -92,13 +92,7 @@ bool DebugOptions::ParseOption(const std::string& option) {
     argument = option.substr(pos + 1);
   }
 
-  // --debug and --inspect are mutually exclusive
-  if (option_name == "--debug") {
-    debugger_enabled_ = true;
-  } else if (option_name == "--debug-brk") {
-    debugger_enabled_ = true;
-    wait_connect_ = true;
-  } else if (option_name == "--inspect") {
+  if (option_name == "--inspect") {
     debugger_enabled_ = true;
     enable_inspector = true;
   } else if (option_name == "--inspect-brk") {
@@ -108,7 +102,7 @@ bool DebugOptions::ParseOption(const std::string& option) {
   } else if ((option_name != "--debug-port" &&
               option_name != "--inspect-port") ||
               !has_argument) {
-    // only other valid possibility is --debug-port,
+    // only other valid possibility is --inspect-port,
     // which requires an argument
     return false;
   }

test/parallel/test-cluster-inspector-debug-port.js

@@ -25,11 +25,9 @@ if (cluster.isMaster) {
   fork(1);
   fork(2, ['--inspect']);
   fork(3, [`--inspect=${debuggerPort}`]);
-  fork(4, ['--inspect', '--debug']);
-  fork(5, [`--debug=${debuggerPort}`, '--inspect']);
-  fork(6, ['--inspect', `--debug-port=${debuggerPort}`]);
-  fork(7, [`--inspect-port=${debuggerPort}`]);
-  fork(8, ['--inspect', `--inspect-port=${debuggerPort}`]);
+  fork(4, ['--inspect', `--debug-port=${debuggerPort}`]);
+  fork(5, [`--inspect-port=${debuggerPort}`]);
+  fork(6, ['--inspect', `--inspect-port=${debuggerPort}`]);
 } else {
   const hasDebugArg = process.execArgv.some(function(arg) {
     return /inspect/.test(arg);