TextureGroup / Texture

…loads (#1948)

* Exposes a new option in ASImageDownloaderProtocol to retry image downloads

At the moment the ASBasicImageDownloader does not automatically retry image downloads if the remote
host is unreachable. On the contrary the ASPINRemoteImageDownloader automatically retries. Retrying is
something that ultimately clients need to be able to control, for example to fail fast to an alternative image
rather than keep retrying for more than one minute while not displaying any image. This change exposes
a new option in the ASImageDownloaderProtocol to retry image downloads. It also uses this new option
in both ASNetworkImageNode and also ASMultiplexImageNode, setting it to YES to preserve the current
behaviour.

* Fixes a failing test in ASMultiplexImageNodeTests

* Fixes ScreenNode.m

ScreenNode.m is implementing ASImageDownloaderProtocol and needs to
be fixed to reflect changes in the latter.

* Return nil instead of empty array when no accessibility elements are found. Fixes #1954.

* Use nullability annotations to fix static analyzer warnings.

* Add UI test target.

* Add UI test to make sure web view stays accessible.

* Revert "Add UI test to make sure web view stays accessible."

This reverts commit 00253f4.

* Revert "Add UI test target."

This reverts commit 288b5e0.

* Add unit test to make sure accessibility elements are correct when a WKWebView is wrapped in an ASDisplayNode.

…roperties from its Element's node (#1941)

* Trying to make ASTextLinePositionModifier public

* d’oh

* be a little more restrictive on the files we pull into the pod

* Never mind, I guess we need all of these

* update the project file as well

* try this again

* I think this will work this time.

Closes #1850.

* Account for possible inverted transform during hit test

When ASCollectionNode has the `inverted` flag set, a transform gets
set on the cell node. We need to make sure that we account for that
when dealing in the view coordinates.

* Store self.node and self.node.view in local variables for better readability.

* Add a test for hit testing in an inverted ASCollectionNode

* Fix failing ASConfigurationTests

* Update configuration.json as well

Follow up on #1911: it's not enough to execute step 3 on the main thread because -_allocateNodesFromElements: uses ASDispatchApply to offload the work to other threads. So this diff adds a flag to tell that method to do everything serially on the calling thread.

…n thread (#1911)

* Add an experiment that makes ASDataController to do everything on main thread

Under this experiment, ASDataController will allocate and layout all nodes on the main thread. This helps to avoid deadlocks that would otherwise occur if some of the node allocations or layouts caused ASDataController's background queue to block on main thread. As a bonus, this experiment also helps to measure how much performance wins we get from doing the work off main.

* Remove ASSERT_ON_EDITING_QUEUE

* Add experiment to disable global textkit lock

* Forgot the bang

* Do not expose tgmath.h to all clients of Texture

- tgmath.h #undef the `log` macro for mathematical reasons. Code that may also use a log name (such as CocoaLumberjack) will get confused by this when they try to use `NS_SWIFT_NAME` with `log` as part of the name.
- `ABS` from NSObjCRuntime.h is what is typically used for abs on `CGFloat`.
- Note: removing tgmath.h from the Texture umbrella header may expose clients that implicitly depended upon it being imported. Sources may have to be updated after this to `#import <tgmath.h>` explicitly.

* Remove background deallocation helper code

Last use removed in Texture with #1840, now PINS no longer uses it either. Less OOMs is so nice.

* remove methods from docs

…1888)

We did not notice any effect on performance of the Pinterest app by not caching `accessibilityElements` in `_ASDisplayView`. By not caching the elements, we can be sure that the elements will be correct even when nodes change visibility state. There will be a performance impact when voice over is enabled, but providing the correct elements for the current state of a view is more important than performance in this case.

#1853

* Renames AS_EXTERN and ASViewController

To ASDK_EXTERN and ASDKViewController.
This is to avoid conflicting with AuthenticationServices in
Xcode 12

* Fix up examples and docs

* Add bit about updating ASViewController rename

* Add `ASImageCacherCompletion` breaking API change.

* Remove unnecessary trailing pounds.

…son.

…Image (#1861)

* Fix -[ASNetworkImageNode setURL:resetToDefault:] forget to reset animatedImage

* add ASNetworkImageNodeTest for reset with animatedImage

Most of this code comes from an old PR that @fruitcoder put up #795 2 years ago.

When creating our array of accessibilityElements, we need to respect the value of `accessibilityElementsHidden`. If the value of this property changes, we need to invalidate the cached accessibility elements (unless we are in the experiment that doesn’t cache `accessibilityElements`).

I created a simple test app and made sure this matched UIKit’s implementation. I also added a test case that changes the value of `accessibilityElementsHidden` and makes sure the proper accessibilityElements are returned.