fix(Popover): Apply fill class to popover target when fill prop is passed

[ggdouglas]

Problem

When the fill prop is passed to Tooltip or other Popover-based components, the .bp6-fill class was not being applied to the .bp6-popover-target wrapper div. This caused layout issues when using these components in flex containers, particularly when placing buttons side-by-side where one or more are wrapped in a tooltip.

When wrapping a button with fill={true} in a Tooltip with fill={true}, the button would not fill its container as expected.

Example:

<Flex gap={2} width="100">
    <Button fill={true}>Cancel</Button>
    <Tooltip fill={true} content="Some content.">
        <Button fill={true} intent="primary">Submit</Button>
    </Tooltip>
</Flex>

https://codesandbox.io/p/sandbox/r93ft3

Root Cause

The Popover component's target wrapper was missing the Classes.FILL class in its className computation, even when the fill prop was passed.

Example

Given the following use case / layout pattern:

<Flex gap={2}>
    <Button fill={true}>Cancel</Button>
    <Tooltip fill={true} content="Some content.">
        <Button fill={true} intent="primary">Submit</Button>
    </Tooltip>
</Flex>

---

Before: The popover target wrapper lacks the .bp6-fill class.

...
<div class="bp6-popover-target">
    <button class="bp6-button bp6-fill bp6-intent-primary">Submit</button>
</div>

After: The popover target wrapper now includes .bp6-fill.

...
<div class="bp6-popover-target bp6-fill">
    <button class="bp6-button bp6-fill bp6-intent-primary">Submit</button>
</div>

This results in both buttons displaying as equal width as expected.

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Description

[Popover] Apply fill class to popover target when fill prop is passed

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[svc-palantir-github]

Apply fill class to popover target when `fill` prop is passed

Build artifact links for this commit: documentation | landing | table | demo

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🐛 Fixes

• [Popover] Apply fill class to popover target when fill prop is passed (#7635)

[svc-palantir-github]

Add test case

Build artifact links for this commit: documentation | landing | table | demo

This is an automated comment from the deploy-preview CircleCI job.