1665568 - tabs.sendMessage(badid, msg) = "An unexpected error occurred" + "tab is null" instead of "Could not establish connection. Receiving end does not exist."

Status: RESOLVED FIXED

(WebExtensions :: General, defect, P3)

Description

[Rob Wu [:robwu]]

browser.tabs.sendMessage(12345, "msg"); used to reject with:

"Could not establish connection. Receiving end does not exist."

but now it rejects with:

"An unexpected error occurred"

and the global JS console shows:

tab is null ExtensionParent.jsm:309
getTopBrowsingContextId resource://gre/modules/ExtensionParent.jsm:309
normalizeArgs resource://gre/modules/ExtensionParent.jsm:324

We should fix this, by:

• adding a check for !tab to https://searchfox.org/mozilla-central/rev/f4b4008f5ee00f5afa3095f48c54f16828e4b22b/toolkit/components/extensions/ExtensionParent.jsm#309
• updating the unit test to use browser.test.assertRejects instead of the non-functional test at https://searchfox.org/mozilla-central/rev/f4b4008f5ee00f5afa3095f48c54f16828e4b22b/browser/components/extensions/test/browser/browser_ext_tabs_sendMessage.js#363-369 . That current test is not doing anything because browser.tabs.sendMessage is async, so thetry-catch` does not catch the rejection.

Comment 2

[Rob Wu [:robwu]]

Fixing this is very doable for beginners (with the steps mentioned above), I'll mentor this bug.

To get started, see https://wiki.mozilla.org/WebExtensions/Contribution_Onramp

Comment 3

[Richa Sharma]

I would like to give this a shot. Setting up the dev environment right now would try to have a patch ready soon.

Comment 4

[Richa Sharma]

Attachment: Bug 1665568 - Throw no receiver error if tab is not available. r=robwu

Comment 5

[Pulsebot]

Pushed by [e-mail]:
https://hg.mozilla.org/integration/autoland/rev/37f7e8b9f72b
Throw no receiver error if tab is not available. r=robwu

Comment 6

[Natalia Csoregi [:nataliaCs]]

https://hg.mozilla.org/mozilla-central/rev/37f7e8b9f72b

Comment 7

[Caitlin Neiman [:caitmuenster]]

Thanks so much, Richa! 🎉 Your contribution has been added to our recognition wiki: https://wiki.mozilla.org/Add-ons/Contribute/Recognition

Welcome onboard! We look forward to seeing you around. 😎