Junit 5 ConcurrentModificationException update for BinarySearchTreeTest

[mmaurier]

Here's the code change for Junit 5 on BinarySearchTreeTest for ConcurrentModificationException:

@test
public void concurrentModificationErrorRemovingPreOrder() throws ConcurrentModificationException {

Assertions.assertThrows(ConcurrentModificationException.class, () -> {
		
	BinarySearchTree<Integer> bst = new BinarySearchTree<>();
		
	bst.add(1);
	bst.add(2);
	bst.add(3);
		
	Iterator<Integer> iter = bst.traverse(TreeTraversalOrder.PRE_ORDER);
		
	while (iter.hasNext()) {
		bst.remove(2);
		iter.next();
	}
});

}

Same goes for InOrder, PostOrder, and LeveOrder test.

[williamfiset]

The current impl is using Junit 4 and is WAI. Please send a PR if you want to upgrade to Junit 5, altough that might breaks other tests along the way

https://github.com/williamfiset/Algorithms/blob/master/build.gradle#L35

[mmaurier]

Sounds good. I'll start a branch called 'Update to Junit5'. I'm studying for an interview with Google next month using your Algorithms repository and your youtube video also. Can you leave the branch open until I finish with the entire repository? This way we avoid breaking other test cases and you can test the branch at your own leisure.