Make sure that a Tooltip doesn't crash in 0x0 environment

[ahmedsameha1]

This is my attempt to handle #6537 for the Tooltip widget.

[gemini-code-assist]

Code Review

This pull request adds a regression test to ensure that a Tooltip with a zero-sized child does not crash the application. This is a valuable addition to prevent future regressions of the issue.

My review includes a suggestion to improve the test to more accurately reflect the conditions of the original crash report. Specifically, I recommend triggering the tooltip to be displayed, as the crash occurred during the tooltip's positioning logic. This will make the test more comprehensive.

[gemini-code-assist]

This test is a great addition to prevent regressions for the zero-sized tooltip crash. However, it can be improved to more accurately reproduce the conditions that led to the original crash.

The current test verifies that a Tooltip constrained to a zero size can be laid out. The original issue, however, was related to a crash during the positioning of the tooltip when it's being displayed. The current test doesn't trigger the tooltip to appear.

Additionally, the issue describes a Tooltip with a zero-sized child, whereas the test has a Tooltip with a null child that is itself constrained to be zero-sized.

The suggested change updates the test to:

1. Wrap a zero-sized widget (SizedBox.shrink()) with the Tooltip, matching the scenario from the issue.
2. Programmatically trigger the tooltip to be shown using ensureTooltipVisible().
3. Verify that the tooltip content is visible, which implicitly confirms that no crash occurred during the positioning and rendering of the tooltip.

This will make the test more robust and ensure it fully covers the intended crash scenario.

  testWidgets('Tooltip does not crash at zero area', (WidgetTester tester) async {
    final GlobalKey<TooltipState> tooltipKey = GlobalKey<TooltipState>();
    await tester.pumpWidget(
      MaterialApp(
        home: Center(
          child: Tooltip(
            key: tooltipKey,
            message: 'X',
            child: const SizedBox.shrink(),
          ),
        ),
      ),
    );
    expect(tester.getSize(find.byType(Tooltip)), Size.zero);

    // Trigger the tooltip to ensure the positioning logic doesn't crash.
    tooltipKey.currentState!.ensureTooltipVisible();
    await tester.pump(); // Start the tooltip animation.
    await tester.pump(const Duration(seconds: 2)); // Wait for it to be fully visible.

    // Verifying the tooltip is visible confirms that no crash occurred during positioning.
    expect(find.text('X'), findsOneWidget);
  });

[victorsanni]

Should we check that the tooltip is of size zero after ensuring it is visible?

[dkwingsmt]

I suggest we should use set the view size to zero since the tooltip is an overlay.

[auto-submit]

autosubmit label was removed for flutter/flutter/178461, because - The status or check suite Linux analyze has failed. Please fix the issues identified (or deflake) before re-applying this label.