Fix PR Preview

[anssiko]

Die On: warning metadata even if valid causes PR Preview to fail

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💥 Error: 400 Bad Request 💥

PR Preview failed to build. (Last tried on Jan 18, 2024, 8:08 AM UTC).

More

PR Preview relies on a number of web services to run. There seems to be an issue with the following one:

🚨 CSS Spec Preprocessor - CSS Spec Preprocessor is the web service used to build Bikeshed specs.

🔗 Related URL

If you don't have enough information above to solve the error by yourself (or to understand to which web service the error is related to, if any), please file an issue.

[anssiko]

@dontcallmedom I tested my theory and here are the results:

CSS Spec Preprocessor fails if index.bs has Die On: warning metadata option (raw index.bs from PR #515):

💥 https://api.csswg.org/bikeshed/?url=https://raw.githubusercontent.com/webmachinelearning/webnn/aec34293b249e7427e578837ddcb204cf92bca3c/index.bs&force=1&md-warning=not%20ready

Succeeds when Die On: warning is removed (raw index.bs is from this PR):

✅ https://api.csswg.org/bikeshed/?url=https://raw.githubusercontent.com/webmachinelearning/webnn/4eff923b0be529212b815e89e343293f46ad8c07/index.bs&force=1&md-warning=not%20ready

I will merge this fix to hopefully re-enable PR Preview. Folks will need to rebase to pull in this change. If this did not fix it, then we need to dig deeper.

[anssiko]

I was able to validate this fix works with one of my open PRs: #507

After rebasing, force-pushing, I edited the initial comment in the PR to trigger PR Preview re-run and that fixed this bug.

@dontcallmedom is this worth reporting upstream? It feels like we used Die On: warning properly in this spec.

[zolkis]

This is strange.
Of course, we could use the practice to set die on warning in local builds.

[anssiko]

@zolkis, yes, I recommend using the --die-on warning CLI switch in local builds. The CI will still catch any warnings so they won't go in unnoticed.