TypeScript type assertion bypass (@ts-expect-error)

Using @ts-expect-error to bypass type checking for the mocked context (line 46) can lead to brittle tests and maintenance issues if the context shape changes. It is preferable to define a proper mock type or use partial typing to ensure type safety and reduce the risk of runtime errors.

Recommended solution:
Define a mock type for the context or use Partial<AppContextType> to avoid bypassing TypeScript checks:

const mockUseApp: Partial<AppContextType> = { ... };

Insufficient interaction testing for CopyButton

The test only verifies the presence of copy buttons but does not check whether the copyToClipboard function is called when the button is clicked. This misses an important behavioral aspect and reduces test coverage.

Recommended solution:
Add a test that simulates a click on the copy button and asserts that mockUseApp.copyToClipboard is called:

copyButtons[0].props.onClick();
expect(mockUseApp.copyToClipboard).toHaveBeenCalled();

Security: Potential Exposure of Wallet Addresses

The code displays EVM and Solana wallet addresses in the UI (lines 204-227). If the Header component is rendered for unauthenticated or unauthorized users, this could expose sensitive information. Ensure that only authorized users can access this component or that wallet addresses are not displayed unless the user is authenticated.

Recommended Solution:

• Confirm that the parent application enforces authentication and authorization before rendering this component.
• If not, add explicit checks to prevent wallet address exposure to unauthorized users.

The handleCopy function does not handle errors from the asynchronous copyToClipboard operation. If the clipboard operation fails, the UI will still indicate success, which is misleading. Consider wrapping the clipboard call in a try/catch block and providing user feedback on failure:

try {
  await copyToClipboard(value);
  setCopied(true);
  setTimeout(() => setCopied(false), 2000);
} catch (err) {
  // Optionally set an error state or notify the user
}

The use of setTimeout to reset the copied state does not account for the component unmounting before the timeout fires. This can lead to a memory leak or React warning about setting state on an unmounted component. To address this, clear the timeout in a useEffect cleanup function or use a ref to track mounted state.

This implementation has a potential memory leak. If the CopyButton component unmounts before the 2-second timeout completes, setCopied(false) will be called on an unmounted component. This causes a React warning and is not best practice.

To fix this, you should manage the timer with a useEffect hook. This provides a cleanup function to clear the timeout when the component unmounts.

Here's a suggested refactoring (you'll also need to import useEffect from react):

  useEffect(() => {
    if (!copied) return;

    const timerId = setTimeout(() => {
      setCopied(false);
    }, 2000);

    return () => clearTimeout(timerId);
  }, [copied]);

  const handleCopy = async (e: React.MouseEvent) => {
    e.stopPropagation();
    await copyToClipboard(value);
    setCopied(true);
  };

The test file Header.test.tsx is located inside the src/components directory, which is already covered by the "src/**/*.tsx" pattern. The addition of "test/**/*.ts" and "test/**/*.tsx" seems unnecessary if there isn't a separate test directory at the root of the apps/app project.

To keep the configuration clean, you could remove the added test paths.