doc: update output examples in debugger.md

[vsemozhetbyt]

Checklist

• documentation is changed or added
• commit message follows commit guidelines

Affected core subsystem(s)

doc, debugger

• Update examples according to new debugger output (info added, lines reordered).
• Replace x = 5; by explicit global.x = 5; to stress the intent to create a global variable (needed for access from debug REPL).
• Add break marks (>) in output according to real output.
• Update also the Inspector example.

Some updates are done due to previous changes in test/fixtures/break-in-module/main.js and test/fixtures/break-in-module/mod.js files.

[vsemozhetbyt]

/cc @nodejs/documentation

[vsemozhetbyt]

@jasnell Could this be landed?

[jasnell]

I'd like a bit more sign off. @nodejs/documentation

[joshgav]

Two fixes recommended in comments:

1. var x = 5 rather than global.x = 5
2. Don't use a specific UUID in the chrome-devtools URL.

Thanks for the contribution!

[joshgav]

Unfotunately the UUID changes with each Node instance, so we shouldn't use a specific one here. Perhaps a placeholder like <uuid> would be sufficient?

[joshgav]

var x = 5 and the same in the output examples would be more representative of usage IMO.

[joshgav]

var x = 5

[joshgav]

var x = 5

[joshgav]

var x = 5

[vsemozhetbyt]

@joshgav

1. I've replaced UUID with the placeholder.
2. With var x = 5, I get this output:

node debug test.js

< Debugger listening on 127.0.0.1:5858
connecting to 127.0.0.1:5858 ... ok
break in e:\DOC\prg\js\node\-test\test.js:1
> 1 var x = 5;
  2 setTimeout(() => {
  3   debugger;

debug> cont

< hello
break in e:\DOC\prg\js\node\-test\test.js:3
  1 var x = 5;
  2 setTimeout(() => {
> 3   debugger;
  4   console.log('world');
  5 }, 1000);

debug> next

break in e:\DOC\prg\js\node\-test\test.js:4
  2 setTimeout(() => {
  3   debugger;
> 4   console.log('world');
  5 }, 1000);
  6 console.log('hello');

debug> repl

Press Ctrl + C to leave debug repl

> x
ReferenceError: x is not defined

[joshgav]

@vsemozhetbyt

With var x = 5, I get this output

Ah I see, the example is stopping within a callback so that variable isn't there. I guess global.x = 5 makes sense then and in fact might help people better understand what's happening.

It would be great if you have a better idea than the "<uuid>" string 😄 , but there's not really another option at the moment I don't think?

LGTM

[vsemozhetbyt]

@joshgav Sorry, I have not) Does anybody have?

[joyeecheung]

Maybe use an example uuid string and then add a note/comment explaining that string is just an example, it would be generated on the fly?

[vsemozhetbyt]

@joyeecheung Like this?

To start debugging, open the following URL in Chrome:
    chrome-devtools://devtools/bundled/inspector.html?experiments=true&v8only=true&ws=127.0.0.1:9229/dc9010dd-f8b8-4ac5-a510-c1a114ec7d29

(The UUID in the end of the URL is generated on the fly, it will vary.)

[joyeecheung]

@vsemozhetbyt Probably

(In the example above, the UUID dc9010dd-f8b8-4ac5-a510-c1a114ec7d29 at the end of the URL is generated on the fly, it varies in different debugging sessions)

[vsemozhetbyt]

@joyeecheung Done.

[vsemozhetbyt]

@jasnell @joshgav @joyeecheung Could we proceed?

[jasnell]

Still LGTM. @joyeecheung PTAL

[joshgav]

added a period to end of a sentence and landed in ca8c30a

Thanks @vsemozhetbyt!

[italoacasas]

This is not landing clearly in v7.x, any plans to backport?

[gibfahn]

Should this be backported to v6.x-staging? If yes please follow the guide and raise a backport PR, if no let me know or add the dont-land-on label.

[vsemozhetbyt]

@gibfahn Done: #13751