1491397 - Falsey userScriptOptions.scriptMetadata are not available

Status: VERIFIED FIXED

(WebExtensions :: General, defect, P5)

Description

[Rob Wu [:robwu]]

Attachment: scriptMetadata-falsey.zip

If scriptMetadata is falsey (false, 0, "", null, undefined), then the metadata is always undefined.

STR:
1. Load attached extension in Nightly (including patch for bug 1437864).
2. Visit example.com

Expected:
- "Got expected data: 0"

Actual:
- "Unexpected metadata, expected 0, got undefined"

This is caused by the following:
https://searchfox.org/mozilla-central/rev/dd965445ec47fbf3cee566eff93b301666bda0e1/toolkit/components/extensions/ExtensionContent.jsm#650-651
    const clonedMetadata = scriptMetadata ?
            Cu.cloneInto(scriptMetadata, apiScope) : undefined;

How about just declaring clonedMetadata and then lazily cloning the metadata when needed? If the metadata is a large, rarely used object, then that would bring performance benefits.

Comment 1

[Rob Wu [:robwu]]

Attachment: Bug 1491397 - Correctly forward falsey scriptMetadata in userScripts API

This also adds new test coverage for the previously untested features:
- "file" in "js" param to userScripts.register works.
- "allFrames" set to true in userScripts.register works.
- scriptMetadata accepts primitive values, and in particular falsey
  values in particular (= bug 1491397 ).
 - scriptMetadata is the same object in all API script calls.

Comment 2

[Pulsebot]

Pushed by [e-mail]:
https://hg.mozilla.org/integration/autoland/rev/84ceb42728e4
Correctly forward falsey scriptMetadata in userScripts API r=rpl

Comment 3

[Bogdan Tara[:bogdan_tara | bogdant]]

https://hg.mozilla.org/mozilla-central/rev/84ceb42728e4

Comment 4

[Vlad Jiman]

Thank you for the test extension and STR. 
Validated the fix as per expected results from the description using the provided extension on: latest Nightly: 65.0a1 running on Windows 10 x64 and Nightly on Ubuntu 18.04.