tools: python3 compat for inspector code generator

[bnoordhuis]

The code generator takes a dict and turns it into a namedtuple. The dict
contains the key "async", which is a keyword in python 3, and rejected
by the namedtuple constructor. Rename it to "_async" to avoid the clash.

[nodejs-github-bot]

CI: https://ci.nodejs.org/job/node-test-pull-request/25261/

[targos]

Should we upstream this?

[bnoordhuis]

@targos I'm unclear on whether tools/inspector_protocol is an upstream dependency or not. We pull done upstream changes but we also have numerous local changes according to the history.

[nodejs-github-bot]

CI: https://ci.nodejs.org/job/node-test-pull-request/25262/

[bnoordhuis]

There's another code generator in deps/v8/third_party/inspector_protocol that suffers from the same issue, so yes, I guess some upstreaming needs to be done. I'll look into it.

[cclauss]

Nice! Elegant. If we are only using one version of code_generator.py then my preference be to leave the other one untouched so that we can keep an accurate track of our real dependencies as discussed at #29196 (comment)

[bnoordhuis]

I believe the other one is also used so it's going to need the same fixes. As to why there are two (they're very similar), I don't know.

[cclauss]

We seem to have lots of redundant dependencies because we vendor-in and not pip install. Like the conversation at #28555 (comment)

[cclauss]

I think I now see something that has been bugging me for a while about our Travis builds... Try this:

• Start with a clean branch of master
• Edit line 131 of deps/v8/third_party/inspector_protocol/code_generator.py to read
  • sys.stderr.write("Deps: Failed to parse config file: %s\n\n" % exc)
• Edit line 112 of tools/inspector_protocol/code_generator.py
  • sys.stderr.write("Tools: Failed to parse config file: %s\n\n" % exc)
• Now that the error messages are marked, commit and push and watch the Travis tests.
  On the Python 3.7 run there is neither Deps: nor Tools: on the async error message.

This PR: https://travis-ci.com/nodejs/node/jobs/228507267#L1684
The experiment above: https://travis-ci.com/cclauss/node/jobs/228611533#L1676

I believe that this is because Travis CI is not building and testing the branch that you want to test but is instead building and testing master. This is why I have been submitting "small moves" pull requests that only a modify single file. Without the changes being checked into master, the Python 3 Travis CI tests are leading you astray. Am I crazy?

EDIT: Forgive the above... I was mistaken.

I did prove that it is the deps file that we want to modify and not the tools file. Thus #29346

[richardlau]

I believe the other one is also used so it's going to need the same fixes. As to why there are two (they're very similar), I don't know.

One of the things #22680 proposed was to remove one of the two copies of the build files for the inspector protocol but it was argued against by the V8 inspector folks.

[Trott]

I did prove that it is the deps file that we want to modify and not the tools file. Thus #29346

@cclauss So this PR should not land as-is?

[cclauss]

No. This is a PR that we should close because modifies the wrong file. This fix was the right one but the file was the wrong one.

#29346 modifies the correct file and therefore allows us to close #29326.

[cclauss]

Change deps/v8/third_party/inspector_protocol/code_generator.py instead of and tools/inspector_protocol/code_generator.py.

[bnoordhuis]

Both code generators are in use. The changes to the one in deps/ need to be upstreamed first however.

[cclauss]

Minor (conventional) preference for async_ instead of _async https://dbader.org/blog/meaning-of-underscores-in-python

[targos]

I opened https://chromium-review.googlesource.com/c/deps/inspector_protocol/+/1781351 upstream.
@bnoordhuis I hope you don't mind, as I copied your changes.

[cclauss]

Please modify this code to be aligned with the changes made in response to comments on https://chromium-review.googlesource.com/c/deps/inspector_protocol/+/1781351

[bnoordhuis]

@cclaus Done.

[cclauss]

This looks great and aligns with the changes that have now landed upstream:
https://chromium-review.googlesource.com/c/deps/inspector_protocol/+/1781351

This file also exists at deps/v8/third_party/inspector_protocol/code_generator.py so we also need to update that file before we can close #29326