1902711 - TranslationsParent.getTopPreferredSupportedToLang returns false positives

Status: VERIFIED FIXED

(Firefox :: Translations, defect, P2)

Description

[Erik Nordin [:nordzilla]]

Description

When I landed the TranslationsParent.getTopPreferredSupportedToLang() function, I did not sufficiently test all edge cases. I recently discovered that this function is capable of returning a false positive.

It always returns the first language in the preferred languages list, regardless of its supported status.

This works out for languages that we support, but for a language such as Finnish, which, at the time of writing, is only supported as a source language and not a target language, this will return a false positive.

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Steps to reproduce

• Download Firefox Nightly in a language that is not supported as a translations target language, e.g. Finnish at the time of writing.
• Navigate to a web page, e.g. https://es.wikipedia.org.
• Select some text.
• Open the right-click context menu.

Expected Behavior
The context menu offers to translate the text to English since the app locale language is not supported as a translations target.

Actual Behavior
The context menu offers to translate the text to the app locale language, even though it is not supported.

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Steps to implement

• Fix the TranslationsParent.getTopPreferredSupportedToLang() to properly await functions that it calls.

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Tests to implement

• Add tests for this function in various supported/unsupported app locales.

Comment 1

[Erik Nordin [:nordzilla]]

Attachment: Bug 1902711 - Fix TranslationsParent.getTopPreferredSupportedToLang() r=#translations-reviewers!,ohall

Fixes the TranslationsParent.getTopPreferredSupportedToLang()
function to no longer return false positives if the top
language is not supported as a translations target language.

Comment 2

[Erik Nordin [:nordzilla]]

Attachment: Bug 1902711 - Add multi-locale context menu tests r=#translations-reviewers!,ohall

Adds several test cases to test the SelectTranslations
context-menu offering with various locale and web content
languages.

Depends on D213808

Comment 3

[Phabricator Automation]

Comment on attachment 9407639 [details]
Bug 1902711 - Add multi-locale context menu tests r=#translations-reviewers!,ohall

Revision D213844 was moved to bug 1902859. Setting attachment 9407639 [details] to obsolete.

Comment 4

[Pulsebot]

Pushed by [e-mail]:
https://hg.mozilla.org/integration/autoland/rev/a047490b0519
Fix TranslationsParent.getTopPreferredSupportedToLang() r=ohall,translations-reviewers

Comment 5

[Cristian Tuns]

https://hg.mozilla.org/mozilla-central/rev/a047490b0519

Comment 6

[Erik Nordin [:nordzilla]]

Attachment: Bug 1902711 - Fix TranslationsParent.getTopPreferredSupportedToLang()

Fixes the TranslationsParent.getTopPreferredSupportedToLang()
function to no longer return false positives if the top
language is not supported as a translations target language.

Original Revision: https://phabricator.services.mozilla.com/D213808

Comment 7

[Pulsebot]

https://hg.mozilla.org/releases/mozilla-beta/rev/a4b0e4ad8538

Comment 8

[Daniel Bodea [:danibodea]]

I can reproduce this issue in Nightly v129.0a1 (2024-06-15) (FI locale, Suomi) and verify the fix in Nightly v129.0a1 (2024-06-20) (FI locale, Suomi) and Beta v128.0b5 (FI locale, Suomi language). When attempting to translate a supported language, the target language is English by default since Suomi is not supported as a target language. This was tested in Windows 10, MacOS11 and Ubuntu22.