Section defaultIsOpen does the opposite of the provided boolean

[nerdstep]

Environment

• Package version(s): 5.2.0
• Operating System: Windows 11
• Browser name and version: Chrome 115

Code Sandbox

Link to a minimal repro (fork this code sandbox): https://codesandbox.io/p/sandbox/objective-easley-stwn3x

Steps to reproduce

1. See linked code sandbox.

Actual behavior

The Section component collapseProps.defaultIsOpen does the opposite of what is expected, i.e. when defaultIsOpen={true} the collapse is closed, and when defaultIsOpen={false} the collapse is open.

Expected behavior

When defaultIsOpen={true} the collapse should initially be open.

Possible solution

The component defines an useState variable called isCollapsed which is initialized with the defaultIsOpen value. This value should be negated when initially provided to useState.

const [isCollapsed, setIsCollapsed] = React.useState<boolean>(!collapseProps?.defaultIsOpen ?? false);

https://github.com/palantir/blueprint/blob/develop/packages/core/src/components/section/section.tsx#L112C67-L112C68