Debugging

Here are some notes I put together while trying to get debugging working. I’m looking for suggestions on how to get this to work.

Environment

osx 10.11.2 node v4.4.7 npm@3.10.3 node-inspector@0.12.8 babel-watch@2.0.2

Node command line flag order

Does not work: node ./test.js --debug-brk Works: node --debug-brk ./test.js

Ref: https://github.com/nodejs/node/blob/master/src/node.cc#L3420

Cannot change order of flags passed to babel-watch

Babel watch thinks that the first argument in babel-watch --debug-brk ./test.js is a file. The offending three lines begin at https://github.com/kmagiera/babel-watch/blob/master/babel-watch.js#L92

Args passed to babel watch don’t seem to influence node arguments on spawned node process (forking the runner.js script)

Am I correct in understanding that in runner.js, runMain just loads the modules? Ref: https://github.com/nodejs/node/blob/master/lib/module.js#L573 If this is true, then we cannot expect node arguments to be propagated at the point runMain is called. Ref: https://github.com/kmagiera/babel-watch/blob/master/runner.js#L87

Alternative attempt at passing node arguments to child process

Changing https://github.com/kmagiera/babel-watch/blob/master/babel-watch.js#L240 to const app = fork(path.resolve(__dirname, 'runner.js'), {execArgv: ['--debug-brk']}); seems to do this to ps

26214   0.0  0.2  3671444  39284 s012  S+   12:51AM   0:00.48 /Users/n/.nvm/versions/node/v4.4.7/bin/node --debug-brk /Users/n/P/node_modules/babel-watch/runner.js
26210   0.0  0.2  3104508  41884 s012  S+   12:51AM   0:00.64 node /Users/n/P/node_modules/.bin/babel-watch ./test.js
26208   0.0  0.5  3121008  82492 s013  S+   12:50AM   0:02.60 node /Users/n/P/node_modules/.bin/node-inspector

But this just stops at module.js:409 and then doesn’t even run the test script when unpaused.

This is the closest I’ve gotten so far.

Ref: https://github.com/nodejs/node/blob/master/lib/child_process.js#L39

Endnote

As an aside, I’m curious why you decided not to read from .babelrc or package.json.

Thanks for putting this together. I find it to be the nicest approach out there for loading transpiled files.

[scarlac]

None of the options above will work today. --debug is deprecated and attempting to use --inspect=0.0.0.0:9222 will be ignored and instead --inspect will be passed, meaning you cannot configure it. For programs running in Docker, this means inspector will not be able to connect since debugger only allows container-local connections. On top of that, pressing CTRL+C will not abort the process and you must kill the process manually to stop babel-watch.

Example:

14:16:52 ~/jobs/project ⚡️ node --inspect=0.0.0.0:9222 node_modules/.bin/babel-watch -- test.js
Debugger listening on ws://0.0.0.0:9222/0fdba86a-fafc-4178-9a25-004da4f2792e
For help see https://nodejs.org/en/docs/inspector
Starting inspector on 0.0.0.0:9222 failed: address already in use
^C^C^C

Nothing happens here, and node inspector can connect but will be unable to actually debug anything or even do simple console commands. I also tried switching around -- so it was: node --inspect=0.0.0.0:9222 -- node_modules/.bin/babel-watch test.js with no mentionable change in behavior. Same goes for --debug where I’m instead thrown a deprecation warning.

Any plans on improving this?

[evert]

We’re also stuck on this. We need to be able to bind the inspector on 0.0.0.0.