fix(tooltip): prevent delayed tooltip after target moves - 21.2.x

[viktorkombov]

Closes #17465

Description

Fixes delayed tooltips opening after their target has moved away from the pointer.

This could occur when layout changes—particularly during grid virtualization—move or recycle a target during showDelay without the browser emitting pointerleave. The pending timeout would then open a stale tooltip, sometimes resulting in incorrectly positioned or multiple visible tooltips.

Implementation

For delayed hover interactions, IgxTooltipTargetDirective now:

• Tracks the latest pointer position.
• Uses elementFromPoint() before opening.
• Opens only when the target remains under the pointer.
• Supports targets inside both document and Shadow DOM roots.

The validation is limited to delayed hover interactions. Zero-delay tooltips, focus/click triggers, showTooltip(), and coordinate-less synthetic events preserve their previous behavior.

The fix is contained within the tooltip directive and does not introduce grid-specific handling.

Tests

Added regression coverage verifying that:

• A delayed tooltip remains closed when its target moves away.
• Zero-delay hover interactions are not hit-tested.
• The latest pointer position is used before opening.

Tooltip test suite: 67/67 passing.

Components Affected

Tooltip, including tooltip targets rendered inside virtualized Grid, Tree Grid, and Hierarchical Grid cells.

Type of Change (check all that apply):

• Bug fix
• New functionality
• Breaking change (fix or feature that would cause existing functionality to not work as expected)
• Refactoring (no functional changes)
• Documentation
• Demos
• CI/CD
• Tests
• Changelog
• Skills/Agents

Component(s) / Area(s) Affected:

How Has This Been Tested?

• Unit tests
• Manual testing
• Automated e2e tests

Test Configuration:

• Angular version:
• Browser(s):
• OS:

Screenshots / Recordings

Checklist:

• All relevant tags have been applied to this PR
• This PR includes unit tests covering all the new code (test guidelines)
• This PR includes API docs for newly added methods/properties (api docs guidelines)
• This PR includes feature/README.MD updates for the feature docs
• This PR includes general feature table updates in the root README.MD
• This PR includes CHANGELOG.MD updates for newly added functionality
• This PR contains breaking changes
• This PR includes ng update migrations for the breaking changes (migrations guidelines)
• This PR includes behavioral changes and the feature specification has been updated with them
• Accessibility (ARIA, keyboard navigation, focus management) has been verified

[Copilot]

Pull request overview

Fixes a tooltip regression where a delayed hover tooltip could still open after its target element has moved (e.g., during Grid virtualization) without a corresponding pointerleave, by validating the pending delayed-open against the current hit-tested element under the pointer.

Changes:

• Track the latest pointer coordinates during delayed hover interactions and validate at timeout completion before opening.
• Use elementFromPoint() against the appropriate DocumentOrShadowRoot to ensure the tooltip target is still under the pointer.
• Add regression tests covering “target moved during showDelay”, “no hit-test for zero showDelay”, and “latest pointer position wins”.

Reviewed changes

Copilot reviewed 2 out of 2 changed files in this pull request and generated no comments.

File	Description
projects/igniteui-angular/directives/src/directives/tooltip/tooltip-target.directive.ts	Adds delayed-hover pointer tracking + hit-testing gate before opening to prevent stale delayed tooltips.
projects/igniteui-angular/directives/src/directives/tooltip/tooltip.directive.spec.ts	Adds regression coverage for the delayed-hover hit-testing behavior and updates the hover helper to pass pointer coordinates.