Attempt at making TreeNode more flexible

[ogxd]

Here is an attempt at making it even more flexible, EG usable with thread IDs.

Main difference is that TreeNode no longer has inclusive / exclusive numeric fields. Instead it will store whatever object you need to store, like a group of thread IDs. Then you can use the optional get_inclusive_value function get an inclusive view of whatever data you have in there. It's a little less performant because it's not precomputed but it's no big hassle since this is computed after the report generation stage.

See this "test" I added:

type FunctionID = u32;
type ThreadID = u32;

// Required to wrap Vec<ThreadID> in order to implement AddAssign
#[derive(Clone, Default, Debug)]
pub struct Threads(Vec<ThreadID>);

// Implement AddAssign for get_inclusive_value to be usable
impl AddAssign for Threads {
    fn add_assign(&mut self, other: Self) {
        self.0.extend(other.0);
    }
}

let sequences: HashMap<Vec<FunctionID>, Threads> = HashMap::from([
    (vec![1, 2, 3], Threads(vec![1001, 1002, 1003])),
    (vec![2, 2, 3], Threads(vec![1004, 1005])),
    (vec![1, 2], Threads(vec![1006])),
    (vec![1, 2, 4], Threads(vec![1007, 1008, 1009])),
    (vec![1, 3, 5], Threads(vec![1010])),
    (vec![2, 3, 2, 1, 4], Threads(vec![1010, 1011, 1012, 1013])),
    (vec![1, 3, 5, 1], Threads(vec![1014, 1015])),
]);

let mut tree = TreeNode::build_from_sequences(&sequences, 0);

println!("Unsorted:");
print(&tree, 0, &|node| format!("{} [inc:{:?}, exc:{:?}]", node.key, node.get_inclusive_value(), node.value));

// Sorts by descending inclusive value
// Here we use get_inclusive_value() to aggregate threads by inclusive paths and then len() to compute to total count for the sorting to operate on
tree.sort_by(&|a, b| b.get_inclusive_value().0.len().cmp(&a.get_inclusive_value().0.len()));

println!("Sorted:");
print(&tree, 0, &|node| format!("{} [inc:{:?}, exc:{:?}]", node.key, node.get_inclusive_value(), node.value));

Here is the sorted output:

- 0 [inc:Threads([1006, 1001, 1002, 1003, 1007, 1008, 1009, 1010, 1014, 1015, 1010, 1011, 1012, 1013, 1004, 1005]), exc:None]
 - 1 [inc:Threads([1006, 1001, 1002, 1003, 1007, 1008, 1009, 1010, 1014, 1015]), exc:None]
  - 2 [inc:Threads([1006, 1001, 1002, 1003, 1007, 1008, 1009]), exc:Some(Threads([1006]))]
   - 3 [inc:Threads([1001, 1002, 1003]), exc:Some(Threads([1001, 1002, 1003]))]
   - 4 [inc:Threads([1007, 1008, 1009]), exc:Some(Threads([1007, 1008, 1009]))]
  - 3 [inc:Threads([1010, 1014, 1015]), exc:None]
   - 5 [inc:Threads([1010, 1014, 1015]), exc:Some(Threads([1010]))]
    - 1 [inc:Threads([1014, 1015]), exc:Some(Threads([1014, 1015]))]
 - 2 [inc:Threads([1010, 1011, 1012, 1013, 1004, 1005]), exc:None]
  - 3 [inc:Threads([1010, 1011, 1012, 1013]), exc:None]
   - 2 [inc:Threads([1010, 1011, 1012, 1013]), exc:None]
    - 1 [inc:Threads([1010, 1011, 1012, 1013]), exc:None]
     - 4 [inc:Threads([1010, 1011, 1012, 1013]), exc:Some(Threads([1010, 1011, 1012, 1013]))]
  - 2 [inc:Threads([1004, 1005]), exc:None]
   - 3 [inc:Threads([1004, 1005]), exc:Some(Threads([1004, 1005]))]