gyp: cherrypick python3 changes to input.py from node-gyp

[cclauss]

Built on the lessons learned in #29130 if we bring all changes done to this file in node-gyp, that breaks our Travis CI tests so this PR cherrypicks only the Python 3 compatibility changes. These changes are somewhat complex because the complier module was removed in Python 3 in favor of ast which was introduced in Python 2.5.

Checklist

• make -j4 test (UNIX), or vcbuild test (Windows) passes
• tests and/or benchmarks are included
• documentation is changed or added
• commit message follows commit guidelines

[targos]

rubber-stamp

[nodejs-github-bot]

CI: https://ci.nodejs.org/job/node-test-pull-request/25010/

[sam-github]

I doubt this will pass ci's linter check on the commit messages, the 2 last commits should be squashed into the first --- I'd do it, but @cclauss your branch is protected, you'll have to unprotect it, or do the squashing yourself, or perhaps it can be done on landing if ci is green, I'm not sure if we do that.

[nodejs-github-bot]

CI: https://ci.nodejs.org/job/node-test-pull-request/25012/

[nodejs-github-bot]

CI: https://ci.nodejs.org/job/node-test-pull-request/25013/

[Trott]

Rubber-stamp LGTM

[nodejs-github-bot]

CI: https://ci.nodejs.org/job/node-test-pull-request/25064/

[nodejs-github-bot]

CI: https://ci.nodejs.org/job/node-test-pull-request/25066/

[Trott]

What's the best way to land this? Squash everything into a single commit?

[gengjiawen]

What's the best way to land this? Squash everything into a single commit?

+1 to squash the commit.

[cclauss]

I usually squash like this combined with a well timed git rebase -i master.

However that creates merge commits and requires force push which does not work for this community. Can someone point me to the handful of commands that would allow me to squash without causing rework? A pointer here or I am @cclauss on Slack.

[bnoordhuis]

@cclauss git pull --rebase && git rebase -i origin/master is what I use. That avoids the merge commit because it's basically a fast-forward.

[bnoordhuis]

Style nit: single quotes.

[cclauss]

The Python Software Foundation is going in the opposite direction so the muscle memory is building up but will fix.

[bnoordhuis]

I suppose this might cause a runtime exception when the output contains e.g. latin1-encoded file paths?

[cclauss]

You are correct. There is the old adage that you can never accurately guess encodings -- you have to be told. Should we leave as is or how should we resolve? We could catch the UnicodeDecodeError and then attempt to return s.decode('latin-1') and if we catch another UnicodeDecodeError just return s. Other approaches?

[bnoordhuis]

That sounds reasonable, that probably covers 99% of everyday use.

[nodejs-github-bot]

CI: https://ci.nodejs.org/job/node-test-pull-request/25125/

[Trott]

Landed in 3b92998