tree 83b51bbe66c96b23d0732d64b79d33b0764caaa3
parent 07d16c5b09b13ea13587fc97899c29619a02f304
author wenson_hsieh@apple.com <wenson_hsieh@apple.com@268f45cc-cd09-0410-ab3c-d52691b4dbfc> 1642208182 +0000
committer wenson_hsieh@apple.com <wenson_hsieh@apple.com@268f45cc-cd09-0410-ab3c-d52691b4dbfc> 1642208182 +0000

[iOS] Occasional crash under -[UITargetedPreview initWithView:parameters:target:] when focusing form controls
https://bugs.webkit.org/show_bug.cgi?id=235248
rdar://79220540

Reviewed by Tim Horton and Aditya Keerthi.

Source/WebKit:

It's possible for `-resizableSnapshotViewFromRect:afterScreenUpdates:withCapInsets:` to return a `nil` snapshot
view in the case where a screen update has not been performed yet (among other scenarios). In the case where
UIKit returns `nil` when we're creating the targeted preview for the context menu when focusing a select element
or file input, we'll crash due to an Objective-C exception in the initializer of UITargetedPreview. Mitigate
this by falling back to an empty UIView after requesting the snapshot view to make our code robust against this
scenario.

Test: KeyboardInputTests.DoNotCrashWhenFocusingSelectWithoutViewSnapshot

* UIProcess/ios/WKContentViewInteraction.mm:
(createFallbackTargetedPreview):

Tools:

Add an API test that exercises the crash by forcing `-resizableSnapshotViewFromRect:afterScreenUpdates:withCapInsets:`
to return nil via swizzling.

* TestWebKitAPI/Tests/ios/KeyboardInputTestsIOS.mm:
(TestWebKitAPI::nilResizableSnapshotViewFromRect):
(TestWebKitAPI::TEST):


git-svn-id: http://svn.webkit.org/repository/webkit/trunk@288039 268f45cc-cd09-0410-ab3c-d52691b4dbfc