1740067 - Enable live language switching in Firefox (preffed off)

Status: RESOLVED FIXED

(Core :: Internationalization, enhancement, P3)

Description

[Greg Tatum [:gregtatum]]

The migration to Fluent unlocks dynamic language switching features for Firefox. This would work by allowing users to download a new language pack through about:preferences, and then switching on the fly without restarting. In addition, there may be a flow to present the user with options to change their language during the on-boarding process, potentially based on some heuristics like the setting of the OS's language preferences.

Comment 1

[Itiel]

I think an exception here would be (at least, as things stand atm) switching between RTL and LTR languages (or vice versa).
This requires to flip the UI, and this doesn't work well in all pieces of the UI without a restart.

Comment 2

[Greg Tatum [:gregtatum]]

For this bug I'm going to put in the work to do the live language reloading, but have it behind two prefs.

"intl.multilingual.liveReload" - Will enable live reloading with matching text directions.
"intl.multilingual.liveReloadBidirectional" - Will enable live reloading between RTL and LTR languages.

Then we can follow-up with enabling the prefs.

I'll use Bug 62174 for tracking the remaining work.

Comment 3

[Greg Tatum [:gregtatum]]

Attachment: Bug 1740067 - Rename language switching variables to be more explicit; r?#platform-i18n-reviewers,mstriemer

These were all areas that were confusing me when I was onboarding on to
this code, so I tried to make the terminology less ambiguous and more
precise.

The default language is now the primary language.

UI is now appended to words that are dealing with DOM elements rather
than data stores.

Comment 4

[Greg Tatum [:gregtatum]]

Attachment: Bug 1740067 - Add code documentation to language switching preferences; r?#platform-i18n-reviewers,mstriemer

I felt somewhat disoriented in the code when ramping up on it, so I
started documenting it with JSDoc as way to better understand the code.

Depends on D136019

Comment 5

[Greg Tatum [:gregtatum]]

Attachment: Bug 1740067 - Add live language reloading; r?#platform-i18n-reviewers,mstriemer

The tests are in the next patch.

Depends on D136020

Comment 6

[Greg Tatum [:gregtatum]]

Attachment: Bug 1740067 - Add live language reloading tests; r?#platform-i18n-reviewers,mstriemer

Depends on D136021

Comment 7

[Pulsebot]

Pushed by [e-mail]:
https://hg.mozilla.org/integration/autoland/rev/06d346cb8496
Rename language switching variables to be more explicit; r=mstriemer,platform-i18n-reviewers,preferences-reviewers,nordzilla
https://hg.mozilla.org/integration/autoland/rev/6aacde57e803
Add code documentation to language switching preferences; r=mstriemer,platform-i18n-reviewers,preferences-reviewers,nordzilla
https://hg.mozilla.org/integration/autoland/rev/f975701b3666
Add live language reloading; r=mstriemer,preferences-reviewers
https://hg.mozilla.org/integration/autoland/rev/fa978a15e760
Add live language reloading tests; r=mstriemer,preferences-reviewers

Comment 8

[Norisz Fay [:noriszfay]]

https://hg.mozilla.org/mozilla-central/rev/06d346cb8496
https://hg.mozilla.org/mozilla-central/rev/6aacde57e803
https://hg.mozilla.org/mozilla-central/rev/f975701b3666
https://hg.mozilla.org/mozilla-central/rev/fa978a15e760