inspector: make debug an alias for inspect

[ofrobots]

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

• This commit has a circular dependency on Take --debug-port into account node-inspect#26. I propose that we land here, and then later land upstream.
• test-debugger-pid.js disabled because it depends on ability to debug a
  pid in node-inspect. Once upstream adds this capability, we can enable
  the test back again.

/cc @nodejs/diagnostics @eugeneo @jkrems

[ofrobots]

Removed because inspect behaviour is different from debug. The former stops before reaching the repl. This test doesn't make sense anymore.

[hybrist]

I assume this is to support node --{inspect,debug}-port=1234 {inspect,debug} my-script.js etc.? If so, I'd rather make that explicit.

[hybrist]

Maybe something like this? nodejs/node-inspect#26

[ofrobots]

Done.

[joshgav]

Summary: I think we should wait to alias debug till Node integrates V8 5.8+, and not at the start of Node 8, assuming Node 8 uses V8 5.7. This provides more notification time for those depending on the legacy interface.

Also, there's a lot of code here unrelated to aliasing debug. Could that be separated into another PR? It would make review easier. Thanks!

[joshgav]

--debug is the primary way to activate the legacy debugger interface. Aliasing it to --inspect instead would make it impossible to start that interface. That would break tools which still depend on it.

I think we should keep --debug associated with the legacy debugger as long as possible, i.e. till we update to V8 5.8+.

[joshgav]

Per my previous comment, I think we should not yet alias --debug to --inspect. The reason for not yet aliasing --debug doesn't apply to node debug, but for consistency's sake, we should probably not yet alias node debug to node inspect either.

[ofrobots]

• @joshgav I have updated the PR to only make debug and alias of inspect. --debug will continue to start the old debug protocol. PTAL.
• @jkrems This includes Take --debug-port into account node-inspect#26. This is a circular dependency, but I propose we land it here first (assuming tests pass upstream). Also, once node-inspect has the ability to debug PIDs, we can re-enable test-debugger-pid.js.

This PR no longer affects --debug

[hybrist]

Note to future self: This test will need to be updated once we pull in @addaleax's usage text fix. https://github.com/nodejs/node-inspect/pull/20/files

[hybrist]

👍 to "cherry-picking" that change (I'll try to do another dependency pull soon so the two code bases don't drift apart too much).

[bnoordhuis]

LGTM modulo comment.

[bnoordhuis]

You're leaving behind dead code with this change. Remove stdoutPattern and outputMatched from test(). There may be more.

[ofrobots]

Done.

[bnoordhuis]

I'm afraid this needs a rebase. Seems some conflicting changes were landed today.

[ofrobots]

Yep, working on that now. In any case, I think it might make sense to land after #11431 and #12197 have landed to minimize conflicts.