Summary:
As per https://twitter.com/olebegemann/status/738656134731599872, our use of "main thread" to mean "main queue" seems to be unsafe.
This diff replaces the `NSThread.isMainQueue` checks with dispatch_get_specific(), which is the recommended approach.
I've also replaced all use of "MainThread" terminology with "MainQueue", and taken the opportunity to deprecate the "sync" param of `RCTExecuteOnMainThread()`, which, while we do still use it in a few places, is incredibly unsafe and shouldn't be encouraged.
Reviewed By: javache
Differential Revision: D3384910
fbshipit-source-id: ea7c216013372267b82eb25a38db5eb4cd46a089
Summary:
Previously, if a module implemented `setBridge:` we assumed that it needs to be initialised on the main thread. This assumption was not really warranted however, and it was a barrier to deferring module initialization.
This diff tweaks the rules so that only modules that override `init` or `constantsToExport**` are assumed to require main thread initialization, and others can be created lazily when they are first used.
WARNING: this will be a breaking change to any 3rd party modules that are assuming `setBridge:` is called on the main thread. Those modules should be rewritten to move any code that requires the main thread into `init` or `constantsToExport` instead.
`**` We will also be examining whether `constantsToExport` can be done lazily, but for now any module that uses it will still be created eagerly when the bridge starts up.
Reviewed By: javache
Differential Revision: D3240682
fb-gh-sync-id: 48f309e3158bbccb52141032baf70def3e609371
fbshipit-source-id: 48f309e3158bbccb52141032baf70def3e609371
Summary:Initializing native modules can block the main thread for tens of milliseconds when it starts up, making it difficult to instantiate the bridge on demand without causing a performance blip.
This diff splits up the initialization of modules so that - although they still happen on the main thread - they don't block the thread continuously.
Reviewed By: javache
Differential Revision: D2965438
fb-gh-sync-id: 38c9c9d281e4672b5874d68b57d4c60d1d268344
shipit-source-id: 38c9c9d281e4672b5874d68b57d4c60d1d268344
Summary: The module initialization process is complex and full of race conditions. This diff adds a set of unit tests that verify that modules setup happens in the correct order, and enforces all the various conditions for main/background init.
Reviewed By: javache
Differential Revision: D2994145
fb-gh-sync-id: 92ea84508cdeeb280ff0fb9e9b2dffa8dbc37e66
shipit-source-id: 92ea84508cdeeb280ff0fb9e9b2dffa8dbc37e66
Pieter De Baets
Marc Horowitz
Bhuwan Khattar
Skotch Vail
Nick Lockwood