// rotateLeft performs a left rotation around the node.
func (tc *treeContext) rotateLeft(node *roachpb.RangeTreeNode) (*roachpb.RangeTreeNode, *roachpb.Error) {
right, pErr := tc.getNode(node.RightKey)
if pErr != nil {
return nil, pErr
}
right, pErr = tc.replaceNode(node, right)
if pErr != nil {
return nil, pErr
}
node.RightKey = right.LeftKey
if right.LeftKey != nil {
rightLeft, pErr := tc.getNode(right.LeftKey)
if pErr != nil {
return nil, pErr
}
rightLeft.ParentKey = node.Key
tc.setNode(rightLeft)
}
right.LeftKey = node.Key
node.ParentKey = right.Key
tc.setNode(right)
tc.setNode(node)
return right, nil
}
