Bug 210618 - A slow-starting swipe always latches on the root node
Summary: A slow-starting swipe always latches on the root node
Alias: None
Product: WebKit
Classification: Unclassified
Component: Scrolling (show other bugs)
Version: Safari Technology Preview
Hardware: Unspecified Unspecified
: P2 Normal
Assignee: Simon Fraser (smfr)
Keywords: InRadar
Depends on:
Reported: 2020-04-16 14:25 PDT by Simon Fraser (smfr)
Modified: 2020-04-16 16:05 PDT (History)
9 users (show)

See Also:

testcase (1.08 KB, text/html)
2020-04-16 14:25 PDT, Simon Fraser (smfr)
no flags Details
Patch (9.21 KB, patch)
2020-04-16 15:05 PDT, Simon Fraser (smfr)
no flags Details | Formatted Diff | Diff

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Description Simon Fraser (smfr) 2020-04-16 14:25:32 PDT
Created attachment 396698 [details]

Start a slow swipe over an overflow:scroll, and we'll always latch on the main frame by mistake.

The first event we get has zero deltas, so ScrollingTreeScrollingNode::canScrollWithWheelEvent() returns false for non-root nodes, and true for root nodes. Then we latch on the root node for the rest of the gesture.
Comment 1 Radar WebKit Bug Importer 2020-04-16 14:25:49 PDT
Comment 2 Simon Fraser (smfr) 2020-04-16 15:05:51 PDT
Created attachment 396703 [details]
Comment 3 EWS 2020-04-16 16:05:33 PDT
Committed r260224: <https://trac.webkit.org/changeset/260224>

All reviewed patches have been landed. Closing bug and clearing flags on attachment 396703 [details].