Summary:
The current technique we use to draw text uses linear memory, which means that when text is too long the UIView layer is unable to draw it. This causes the issue described [here](https://github.com/facebook/react-native/issues/19453). On an iOS simulator the bug happens at around 500 lines which is quite annoying. It can also happen on a real device but requires a lot more text.
To be more specific the amount of text doesn't actually matter, it is the size of the UIView that we use to draw the text. When we use `[drawRect:]` the view creates a bitmap to send to the gpu to render, if that bitmap is too big it cannot render.
To fix this we can use `CATiledLayer` which will split drawing into smaller parts, that gets executed when the content is about to be visible. This drawing is also async which means the text can seem to appear during scroll. See https://developer.apple.com/documentation/quartzcore/calayer?language=objc.
`CATiledLayer` also adds some overhead that we don't want when rendering small amount of text. To fix this we can use either a regular `CALayer` or a `CATiledLayer` depending on the size of the view containing the text. I picked 1024 as the threshold which is about 1 screen and a half, and is still smaller than the height needed for the bug to occur when using a regular `CALayer` on a iOS simulator.
Also found this which addresses the problem in a similar manner and took some inspiration from the code linked there https://github.com/GitHawkApp/StyledTextKit/issues/14#issuecomment-395234885
Fixes https://github.com/facebook/react-native/issues/19453
## Changelog
[iOS] [Fixed] - Use CALayers to draw text, fixes rendering for long text
Pull Request resolved: https://github.com/facebook/react-native/pull/24387
Test Plan:
- Added the example I was using to verify the fix to RNTester.
- Made sure all other examples are still rendering properly.
- Tested text selection
Reviewed By: shergin
Differential Revision: D15918277
Pulled By: sammy-SC
fbshipit-source-id: c45409a8413e6e3ad272be39ba527a4e8d349e28
Summary:
I found that on Android we only support 2 fontWeight options, either **normal** or **bold**, even developer can set any numeric value. But iOS supports all possible numeric values. This PR tries to add support for all possible numeric values on Android, even if it's supported only on Android P(28) and above.
This change might break texts where fontWeight use improperly, because this PR removes conversion of values above 500 to BOLD and below 500 to normal.
FYI, also moved **mCustomTypefaceCache** usage up because it was working after unnecessary mFontCache usage.
## Changelog
[Android] [Changed] - add custom font weight support to Text component on Android, only on P(API 28) and above versions.
Pull Request resolved: https://github.com/facebook/react-native/pull/25341
Test Plan: RNTester app's Text examples will show Rubik Regular, Rubik Light, Rubik Bold, Rubik Medium and Rubik Medium Italic texts in corresponding font family, style and weights.
Differential Revision: D15956350
Pulled By: mdvacca
fbshipit-source-id: 61079d953c65fb34ab4497d44c22317912a5a616
Summary: This removes the NetInfo import from RN and moves it to FB internal. Follow-up diffs will move the Android and iOS files as well.
Reviewed By: rubennorte
Differential Revision: D15392486
fbshipit-source-id: b868b671b8d91661bc7634b4662074ae953835be
Summary:
This is a reconstitution of #24190. It extends accessibility actions to include both a name and user facing label. These extensions support both standard and custom actions.
We've also added actions support on Android, and added examples to RNTester showing how both standard and custom accessibility actions are used.
## Changelog
[general] [changed] - Enhanced accessibility actions support
Pull Request resolved: https://github.com/facebook/react-native/pull/24695
Differential Revision: D15391408
Pulled By: cpojer
fbshipit-source-id: 5ed48004d46d9887da53baea7fdcd0e7e15c5739
Summary:
Fix Issue https://github.com/facebook/react-native/issues/24820
It's caused by `_labelsForTags` and `RCTPLTag` being out of sync, the crash might only be one of the issues that this bug was causing.
## Changelog
[iOS] [Fixed] - fix crash on performance logger
Pull Request resolved: https://github.com/facebook/react-native/pull/24821
Differential Revision: D15407291
Pulled By: PeteTheHeat
fbshipit-source-id: c8d2a047fceb9cec981c48fe5181d1b4cbf0976c
Summary:
Removes the hacks we had in place to help Fabric run in RNTester. Runs fine without them now, so let's remove em!
## Changelog
[Internal] [Removed] - RNTester Fabric hax
Pull Request resolved: https://github.com/facebook/react-native/pull/24924
Differential Revision: D15391418
Pulled By: cpojer
fbshipit-source-id: d800f4c2f68f5e68a20a03c65fdf0317072d2c5e
Summary:
This replaces the "new app screen" in the template with the new design from https://github.com/react-native-community/discussions-and-proposals/issues/122
This uses components that are shipped as part of the `react-native` module, but not necessarily as proper components exported by the main `react-native` module. To use these, we use absolute imports to those components.
Related to #24760
[General] [Changed] - Updated new app template design 💖
Pull Request resolved: https://github.com/facebook/react-native/pull/24805
Differential Revision: D15334459
Pulled By: cpojer
fbshipit-source-id: d0b67d08f936eeabd9e93d4e0ff78302b4d6429f
Summary:
Now that inline views are supported on iOS and Android, we can add some examples to RNTester. I brought back examples from https://github.com/facebook/react-native/commit/03663491c6e68409f73d5c9bbc1a2e3c02ee0966.
I also added some new inline view examples in TextInlineView.js. Note that some examples are only supported on iOS because they rely on the inline view being able to size to content. Android's implementation requires that a width and height be specified on the inline view.
Here are the known bugs illustrated by these examples:
- ClippedByText
- Expected: The image/view wraps to the next line (because it is too wide) and gets clipped vertically (because it is too tall).
- iOS bug: The image/view does not get wrapped to the next line
- Android bug: The view gets wrapped to the next line but doesn't get clipped vertically. The image appears to be positioned too low.
- ChangeImageSize/ChangeViewSize:
- Expected: The "Change Image/View Width" button causes the image/view to toggle between a width of 50 and 100.
- iOS bug: First update works. Subsequent updates don't get rendered.
- Android bug: No updates get rendered.
- ChangeInnerViewSize:
- Expected: The "Change Pink View Width" button causes the pink inner view to toggle between a width of 50 and 100.
- iOS bug: First update works but second update **CRASHES** the app.
- Android bug: No updates get rendered.
[Internal] [Added] - Added inline view examples to RNTester
Pull Request resolved: https://github.com/facebook/react-native/pull/24814
Differential Revision: D15318070
Pulled By: cpojer
fbshipit-source-id: 35a4aaab88e477d627456eeb4208c509c42927df
Summary:
See e94b116d76 which broke RNTester in open source. Environment variables are always strings, so "0" is a truthy value. This fixes it.
[iOS] [fixed] - Fixed broken RNTester
Pull Request resolved: https://github.com/facebook/react-native/pull/24736
Reviewed By: fkgozali
Differential Revision: D15272951
Pulled By: hramos
fbshipit-source-id: aa78f229e05cb553f75cdf6fb4f926829e20a557
Summary:
See e94b116d76 which broke RNTester in open source. Environment variables are always strings, so "0" is a truthy value. This fixes it.
[iOS] [fixed] - Fixed broken RNTester
Pull Request resolved: https://github.com/facebook/react-native/pull/24736
Differential Revision: D15240810
Pulled By: hramos
fbshipit-source-id: 76f498222b6ac05131b3820d8356bfee696f46b8
Summary:
Continuation of #24687
> Issue: [Polish the "new app screen"](https://github.com/react-native-community/discussions-and-proposals/issues/122)
> This is the pull request for the new intro screen proposal in react native as directed by cpojer
This PR was created because the previous one could not be pushed to for some reason. I cleaned up a few small things and added the component as an example to RNTester so we can keep iterating. My plan is to land this, and then polish it and make it the default in a follow-up.
[General][Added] - New Intro screen, Icons
Removed Lottie Integration
100% React Native 💥
Pull Request resolved: https://github.com/facebook/react-native/pull/24737
Differential Revision: D15259092
Pulled By: cpojer
fbshipit-source-id: bc141fb1425cf354f29deffd907c37f83fd92c75
Summary:
AccessibilityInfo.announceForAccessibility is currently only available on iOS. I've added the Android specific implementation, updated RNTester, and the documentation.
[Android] [Added] - Added AccessibilityInfo.announceForAccessibility for Android
[General] [Added] - RNTester example for AccessibilityInfo.announceForAccessibility
Pull Request resolved: https://github.com/facebook/react-native/pull/24746
Differential Revision: D15258054
Pulled By: cpojer
fbshipit-source-id: 3e057a5c32b28e30ea2ee74a18854b012cd2dbfd
Summary:
Fix crash in XMLHttpRequest example because `groupTypes` is not supported on android.
[Android] [Fixed] - Fix crash in XMLHttpRequest example on Android
Pull Request resolved: https://github.com/facebook/react-native/pull/24747
Differential Revision: D15258037
Pulled By: cpojer
fbshipit-source-id: 73086dc92ceb065200e0faafaf100fa742b387bb
Summary:
See #24316 for the motivation. This commit rewrites a couple more new imports in the RNTester project so they use path-based requires.
[General] [Changed] - Migrate TurboModule example in RNTester to use path-based requires
Pull Request resolved: https://github.com/facebook/react-native/pull/24754
Differential Revision: D15258015
Pulled By: cpojer
fbshipit-source-id: adb298cb3006ea0afcd3b813a2e2fe85017764d2
Summary:
In https://github.com/facebook/react-native/pull/23865, RN introduced support for custom fonts the Android Way. But it introduced performance regression because it'll lookup for a font using getIdentifier() every time fontFamily changed. This PR fixes regression by requiring custom fonts to be listed in **fonts** array, and populating **mTypeCache** at first use using the list.
[Android] [Changed] - Require custom fonts to list in **fonts** array. Fixes performance regression.
Pull Request resolved: https://github.com/facebook/react-native/pull/24595
Reviewed By: mdvacca
Differential Revision: D15184590
Pulled By: fkgozali
fbshipit-source-id: e3feb2396609583ebc95101130186a1f5af931da
Summary:
packagingOptions.pickFirst is unreliable that we could not specify which library will be used.
If user have other third party libraries, the story is more complicated.
From the framework point of view, it is better to drop the pickFirst.
In jsc-android 241213.1.0, we did two things:
1. Remove libc++_shared.so in AAR to prevent the conflict with RN.
2. Build by NDK r17c, which aligned with current RN NDK version.
In this commit, I also revert the pickFirst for JSC.
pickFirst JSC also makes upgrade JSC unreliable.
Currently a lot of user report JSC crash issues, those crash issues may relate to JIT and hard to reproduce in-house.
My plan is to make sure user could choose another JSC build easier,
i.e. only to `yarn add 'jsc-android@latest'`.
We could then propose some experimented JSC build for user to check
if the build could help them to fix the crash issue.
[Android] [Fixed] - Remove unreliable packagingOptions.pickFirst for libc++_shared.so and libjsc.so
NOTE that this may not need to add the changelog, as RN 0.59 does not have pickFirst.
This will also reduce a breaking change for upgrade from RN 0.59 or before.
Pull Request resolved: https://github.com/facebook/react-native/pull/24672
Differential Revision: D15164536
Pulled By: cpojer
fbshipit-source-id: 9fc897a77409173a5841f325b38e2836bb07f599
Summary:
Add support for a `CI_USE_BUNDLE_PREFIX` envvar in the RNTester Xcode scheme, as part of ongoing work to enable integration tests in Facebook's internal CI system.
[iOS] [Added] - Add new envvar to support internal iOS tests at Facebook
Reviewed By: cpojer
Differential Revision: D15163397
fbshipit-source-id: 1b75b1868b5f9721a69f6cba4d4052be47e5e5e2
Summary:
The `testBundleURL` test was disabled in open source recently due to issues running it successfully in Facebook's internal CI. We're now skipping `RCTBundleURLProviderTests` tests internally, so it's safe to re-enable now and ensure it runs in Circle CI.
Changelog:
[iOS] [Changed] - Re-enable testBundleURL unit test.
Reviewed By: cpojer
Differential Revision: D15140192
fbshipit-source-id: 5f6a91f3ce8cea245be31dff3ffb86768deab0be
Summary:
Convert root Gradle script to Kotlin DSL, and cleanup. Currently, there is not much benefit or advantage over Groovy scripts, except IDE support and it'll cache compiled KTS scripts on first run.
[Android] [Changed] - Convert root Gradle script to Kotlin DSL, and cleanup.
Pull Request resolved: https://github.com/facebook/react-native/pull/24631
Differential Revision: D15120190
Pulled By: cpojer
fbshipit-source-id: 86691db5c7746e71bb243ebc263c1a3075ee9a9e
Summary:
Assistive technologies use the accessibility role of a component to tell the disabled user what the component is, and provide hints about how to use it. Many important roles do not have analog AccessibilityTraits on iOS. This PR adds many critical roles, such as editabletext, checkbox, menu, and switch to name a few.
Accessibility states are used to convey the current state of a component. This PR adds several critical states such as checked, unchecked, on and off.
[general] [change] - Adds critical accessibility roles and states.
Pull Request resolved: https://github.com/facebook/react-native/pull/24095
Differential Revision: D15079245
Pulled By: cpojer
fbshipit-source-id: 941b30eb8f5d565597e5ea3a04687d9809cbe372
Summary:
This test was disabled in e106112202 to allow unit tests to run on Facebook's internal CI. The change was reverted in 1f6de88230 because another internal test was broken when it found that mainBundleURL() was not getting called.
In this commit, I've commented out the actual piece of code that would cause unit tests to fail in Facebook's internal CI, without removing the call to mainBundleURL(). The localhostBundleURL() method is called elsewhere in the file, so commenting it out here should not cause any issues.
Changelog:
[iOS] [Changed] - Disable testBundleURL test.
Reviewed By: cpojer
Differential Revision: D15049238
fbshipit-source-id: da3a393922f2190b423980cac5ab54df5e7e3e41
Summary:
Updates React Native to use latest CLI.
Changes:
- No more `--reactNativePath`, define it once in the configuration file. This reverts the previous PR that added this flag
- Add `platforms` and `commands` - React Native now defines platform like any other package. There's no longer concept of "out-of-tree" platform. All are treated equally. If React Native works, any other platform will work too.
- Updates `jest/hasteImpl.js` to use public CLI interface (`loadConfig`) instead of `findPlugins` and removes a weird conditional that checks for CI presence.
[INTERNAL] - Update React Native CLI
Pull Request resolved: https://github.com/facebook/react-native/pull/24517
Differential Revision: D15044762
Pulled By: cpojer
fbshipit-source-id: 379b61e842e619312c542173219a7d326663cf24
Summary:
Simplifies the code anyone on iOS using RN has _to see_. In this case, React Native knows that everyone probably wants all these imports (unless they're using dev mode) and so we can auto-import the pod specs for a user from inside the lib.
Basically auto-link for the React side.
[iOS] [Added] - Adds a ruby function which imports the Pods for RN, so that users only have to include this function and it can change per RN version.
Pull Request resolved: https://github.com/facebook/react-native/pull/24555
Differential Revision: D15044780
Pulled By: cpojer
fbshipit-source-id: c3702a52104706def51da6f1d11ab966d57d1edb
Summary:
By default, the text color is `#000000` on iOS and different on Android, e.g. `#808080`, depending on the manufactorer.
This PR changes it so that newly created projects all have the text color `#000000` by default on both iOS and Android.
The argument for this is to make the app by default be more consistent between platforms.
Expo also does this: https://github.com/expo/expo/blob/master/android/expoview/src/main/res/values/styles.xml#L31
---
For context and for your consideration, I have started a discussion here with the topic of whether React Native should try to use OS defaults or be consistent between platforms:
https://github.com/react-native-community/discussions-and-proposals/issues/121
[Android] [Changed] - New projects have a `#000000` by default.
Pull Request resolved: https://github.com/facebook/react-native/pull/24540
Differential Revision: D15044898
Pulled By: cpojer
fbshipit-source-id: 3197266504e1061ac7027bec3100e39e39a4406a
Summary:
Bumps to Xcode 10.2.0 and uses the iOS 12.2 simulator when running tests.
The `testBundleURL` test is temporarily disabled to allow the iOS unit tests to run successfully in the internal Facebook CI system.
Changelog:
[iOS] [Changed] - iOS tests: Bump Xcode to 10.2.0, iOS to 12.2.
Reviewed By: TheSavior
Differential Revision: D14962710
fbshipit-source-id: 769cfb90aacce33903ab6e8dbcc5b5727deacf41
Summary: This installs the sample module to the RNTester.xcodeproj without using any TurboModule infra. This is possible because SampleTurboModule is backward compatible with the existing NativeModules system. This also fixes CI test failure: https://circleci.com/gh/facebook/react-native/84752
Reviewed By: RSNara
Differential Revision: D14987572
fbshipit-source-id: f5f2c4330c7f6558c7d4beeb43198869090dee02
Summary: This is removing packages and libraries from the repo. Any modified buck files simply change the redirect targets to something more appropriate (no logic actually changed)
Differential Revision: D14950721
fbshipit-source-id: 6c14f827b76ca1dbaf83dcb983930f362c6a27d4
Summary:
This showcases SampleTurboModule usage in RNTester. Notes:
* iOS only for now, and you must use cocoapods version.
* You cannot use Chrome debugger when loading this specific example.
As illustrated in the example, the callsite should access `NativeSampleTurboModule` to access the native side.
{F155901711}
Reviewed By: cpojer
Differential Revision: D14932537
fbshipit-source-id: a733e1cd3b642b9e572d5ac6347f4775d495578a
Summary: This sets up RCTSampleTurboModule (and other variants) in RNTester when built with cocoapods. There's no call site yet though. And RNTester.xcodeproj doesn't support it.
Reviewed By: cpojer
Differential Revision: D14932535
fbshipit-source-id: db8eafd6777cbec8f3592dafdccbdd7cf44e38bc
Summary:
For CocoaPods variant only: install TurboModule binding so that sample modules can start using it. This commit only installs `global.__turboModuleProxy` - no sample module is provided.
Note: RNTester.xcodeproj will NOT have TurboModule enabled, due to complication in the .xcodeproj setup (doable, but maybe for some other time...)
To test:
```
console.error(global.__turboModuleProxy == null ? 'BOO' : 'YAY!');
```
Saw `YAY!` in RNTester pod version.
Reviewed By: cpojer
Differential Revision: D14932536
fbshipit-source-id: 3dc083da9154ec320ce6789ec7f2cef5a08fd6a7
Summary: This is to prepare for custom JS runtime binding installation. Note: AppDelegate needs to become .mm
Reviewed By: cpojer
Differential Revision: D14932538
fbshipit-source-id: 30f32223cc405d0cace9e3076b5a2a1d8cc9e3b2
Summary:
This adds https://github.com/mysticatea/abort-controller to polyfill [AbortController](https://developer.mozilla.org/en-US/docs/Web/API/AbortController). This is used to cancel requests when using `fetch`.
This also updates `event-target-shim` to 5.0 to make sure we only have one version of this dependency. This updates required adding a polyfill for `console.assert` which is used by the new version. I made one based on https://github.com/gskinner/console-polyfill/blob/master/console.js#L74.
The polyfill is very small, especially since we already use `event-target-shim` so I think it makes sense to include in core.
Depends on #24418 so that the fetch polyfill supports the `signal` parameter.
Fixes#18115
[General] [Added] - Add support for cancelling fetch requests with AbortController
Pull Request resolved: https://github.com/facebook/react-native/pull/24419
Differential Revision: D14912858
Pulled By: cpojer
fbshipit-source-id: 8a6402910398db51e2f3e3262f07aabdf68fcf72
Summary:
`[RCTBridge setUp]` and `[RCTBridge invalidate]` execute asynchronously and concurrently. Therefore, it's not safe to call one method after the other, as we do in `[RCTBridge reload]`.
In this test, we create a bridge, and immediately reload it. Initializing the bridge causes the JS bundle to execute. Invalidating the bridge causes the jsThread to be terminated. If circumstances are correct, we could end up trying to executing the JS bundle after the jsThread has been terminated, which can lead to these assertions being triggered:
1. `RCTAssert(_jsThread, @"This method must not be called before the JS thread is created");` in `ensureOnJavaScriptThread:`.
2. `RCTAssert(_jsMessageThread != nullptr, @"Cannot invoke completion without jsMessageThread");` in `enqueueApplicationScript:url:onComplete:`.
```
- (void)testUnderlyingBridgeIsDeallocated
{
RCTBridge *bridge;
__weak id batchedBridge;
autoreleasepool {
bridge = [[RCTBridge alloc] initWithBundleURL:_bundleURL moduleProvider:nil launchOptions:nil];
batchedBridge = bridge.batchedBridge;
XCTAssertTrue([batchedBridge isValid], @"RCTBridge impl should be valid");
[bridge reload];
}
RCT_RUN_RUNLOOP_WHILE(batchedBridge != nil)
XCTAssertNotNil(bridge, @"RCTBridge should not have been deallocated");
XCTAssertNil(batchedBridge, @"RCTBridge impl should have been deallocated");
// Wait to complete the test until the new bridge impl is also deallocated
autoreleasepool {
batchedBridge = bridge.batchedBridge;
[bridge invalidate];
bridge = nil;
}
RCT_RUN_RUNLOOP_WHILE(batchedBridge != nil);
XCTAssertNil(batchedBridge);
}
```
To verify that this race is real, patch: P62410422. This adds an artificial delay in the `[RCTCxxBridge start]` method, which makes it so that the bridge is invalidated and the js thread is destroyed before we start executing the jsBundle.
I think a proper solution to this problem would require some bit of restructuring of `[RCTCxxBridge invalidate]` and `[RCTCxxBridge start]` to either:
1. Force `[RCTCxxBridge invalidate]` to wait for `[RCTCxxBridge start]` to complete and vice versa.
2. Make it safe to interleave execution of `[RCTCxxBridge start]` and `[RCTCxxBridge invalidate]`.
I tried the first approach using two semaphores: `_startSem(1)` and `_invalidateSem(0)`. When you start executing the code inside `[RCTCxxBridge start]`, you `semWait(_startSem)`. When you stop executing the code inside `[RCTCxxBridge start]` (which could happen in another thread at some later point in time), you `semSignal(_invalidateSem)`. Likewise, when you start executing `[RCTCxxBridge invalidate]`, you `semWait(_invalidateSem)` and when you stop executing the code inside `[RCTCxxBridge invalidate]` you `semSignal(_startSem)`. This way, invalidates always wait for starts to finish, and starts always wait for invalidates to finish. But considering all the concurrency involved in these methods, this is hard to get right.
The second approach seems possible. You could keep locks for the shared data, and create critical sections whever you want to access that data. I didn't actually try to implement this approach though.
Given that we're going to elminate the Bridge anyway, and that this race condition practically only occurs when you reload imediately after initializing the bridge (which can only really be done programmatically), I think it's fine to just disable the test for now. One other thing I considered was making the current thread sleep for some time after we created the bridge in the test. The reason why I'm hesitant to implement this approach is that it would slow down the execution of the test suite and still wouldn't guarantee that we don't hit this race condition. Ultimately, our infra might end up disabling these tests again.
Reviewed By: shergin
Differential Revision: D14909121
fbshipit-source-id: d7d441c3e2f0ad59182c8c7e23740be4ac4cf83c
Summary:
Android API 26 and Android Support Library 26 added support for font resource type and native/downloadable fonts. It allows apps to easily download fonts from online providers, but also use of various font weights other than normal and bold, like medium. So it deprecated APIs for asset fonts, and should be removed in the future.
Advantages:
- Just copy font files in res/font and use it specifying filename (without extension) in fontFamily
- Define custom font-family using XML file (in res/font) and font files, it may have many weights and styles. See PR for example.
- Define configuration to download fonts from online font providers, and use it.
See https://developer.android.com/guide/topics/ui/look-and-feel/fonts-in-xml and https://developer.android.com/guide/topics/ui/look-and-feel/downloadable-fonts
[Android] [Changed] - add support for custom/downloadable fonts
Pull Request resolved: https://github.com/facebook/react-native/pull/23865
Differential Revision: D14506542
Pulled By: hramos
fbshipit-source-id: 67ba3148fb4b548cdbc779213cf6c1b2c3baffd2
Summary:
See https://github.com/facebook/react-native/issues/24316 for the motivation. This commit rewrites the imports in the RNTester project.
[General] [Changed] - Replaced Haste-style imports with standard path-style imports for RNTester
Pull Request resolved: https://github.com/facebook/react-native/pull/24317
Differential Revision: D14870504
Pulled By: cpojer
fbshipit-source-id: b14f22e7ce559efc332ced032617ca581196d90f
Summary: Just a little more rigorous
Reviewed By: shergin
Differential Revision: D14790912
fbshipit-source-id: 0a4c9b6ea68466efb060c9c90572ff8987fdbd26
Summary:
We need to move animated native module calls to synchronous so we can properly thread them in with mounting instructions in Fabric. Some of them take callbacks so we need to add support for that when switching to synchronous.
A side benefit is that we can unify codepaths a little more with async callbacks.
Reviewed By: shergin
Differential Revision: D14790898
fbshipit-source-id: dc222b9e74375e046e8a9b1b19d72f652dc6722c
