🚨 Error: qc(...).finally is not a function

[ampprojectbot]

Details

Error report: link
First seen: Apr 8, 2020
Frequency: ~ 2,383/day

Stacktrace

Error: qc(...).finally is not a function
    at (https://raw.githubusercontent.com/ampproject/amphtml/2004172112280/extensions/amp-next-page/1.0/service.js:230)
    at build (https://raw.githubusercontent.com/ampproject/amphtml/2004172112280/extensions/amp-next-page/1.0/amp-next-page.js:42)
    at buildCallback (https://raw.githubusercontent.com/ampproject/amphtml/2004172112280/src/custom-element.js:478)
    at (https://raw.githubusercontent.com/ampproject/amphtml/2004172112280/src/custom-element.js:475)
    at build (https://raw.githubusercontent.com/ampproject/amphtml/2004172112280/src/service/resource.js:336)
    at resource (https://raw.githubusercontent.com/ampproject/amphtml/2004172112280/src/service/resources-impl.js:539)
    at buildResourceUnsafe_ (https://raw.githubusercontent.com/ampproject/amphtml/2004172112280/src/service/resources-impl.js:474)
    at buildOrScheduleBuildForResource_ (https://raw.githubusercontent.com/ampproject/amphtml/2004172112280/src/service/resources-impl.js:592)
    at upgraded (https://raw.githubusercontent.com/ampproject/amphtml/2004172112280/src/custom-element.js:384)

Notes

@wassgha modified extensions/amp-next-page/1.0/service.js:230-235 in #26841 (Feb 28, 2020)
@wassgha modified extensions/amp-next-page/1.0/amp-next-page.js:42-45 in #25636 (Dec 10, 2019)
@zhouyx modified src/custom-element.js:477-479 in #14306 (Apr 3, 2018)
@rsimha modified src/custom-element.js:475-475 in #21212 (May 16, 2019)
@rsimha modified src/service/resource.js:336-338 in #21212 (May 16, 2019)
@lannka modified src/service/resources-impl.js:537-542 in #23345 (Jul 17, 2019)
@choumx modified src/service/resources-impl.js:474-474 in #27657 (Apr 9, 2020)
@mkhatib modified src/service/resources-impl.js:592-592 in #4476 (Aug 12, 2016)
@jridgewell modified src/custom-element.js:384-384 in #8229 (Mar 28, 2017)

[rcebulko]

@wassgha for awareness/in case there's an obvious culprit you recognize here. Frequency is pretty low though, so if nothing stands out this can probably be backlogged

[wassgha]

From a quick investigation, it seems like Promise.finally() is not available in some old version of Firefox, I'll defer to @ampproject/wg-runtime to check our polyfills (or whether we should ban usage of .finally if necessary).

[wassgha]

@jridgewell feel free to reassign

[jridgewell]

I think we should ban use of finally, it's an ES2019 feature. The polyfill we have is just to polyfill ES2015 to ES5, not the more recent features.

[jridgewell]

In fact, it's already banned:

amphtml/build-system/test-configs/conformance-config.textproto

Lines 186 to 190 in 97099ce

	requirement: {
	type: BANNED_NAME
	error_message: 'Promise.prototype.finally is not allowed'
	value: 'Promise.prototype.finally'
	}

[wassgha]

@jridgewell how is that enforced? the PRs seem to pass

[jridgewell]

I think I made a mistake, it should be BANNED_PROPERTY_CALL. Looking into it now.

[wassgha]

Sounds good and I'll send a PR to remove usages

[rcebulko]

Thanks for fixing and preventing this y'all!