Move leaf node creation into separate fn

This commit is contained in:
Paul Hauner 2019-04-28 20:30:48 +10:00
parent 58308e3dc5
commit 68b36787e2
No known key found for this signature in database
GPG Key ID: 303E4494BB28068C
2 changed files with 47 additions and 54 deletions

View File

@ -37,7 +37,6 @@ pub struct BTreeOverlay {
offset: usize,
pub depth: usize,
lengths: Vec<usize>,
leaf_nodes: Vec<LeafNode>,
}
impl BTreeOverlay {
@ -49,11 +48,17 @@ impl BTreeOverlay {
}
pub fn from_schema(schema: BTreeSchema, offset: usize) -> Self {
let num_leaf_nodes = schema.lengths.len().next_power_of_two();
let num_internal_nodes = num_leaf_nodes - 1;
Self {
offset,
depth: schema.depth,
lengths: schema.lengths,
}
}
let mut running_offset = offset + num_internal_nodes;
let leaf_nodes: Vec<LeafNode> = schema
pub fn get_leaf_nodes(&self, n: usize) -> Vec<LeafNode> {
let mut running_offset = self.offset + self.num_internal_nodes();
let mut leaf_nodes: Vec<LeafNode> = self
.lengths
.iter()
.map(|length| {
@ -63,12 +68,10 @@ impl BTreeOverlay {
})
.collect();
Self {
offset,
depth: schema.depth,
lengths: schema.lengths,
leaf_nodes,
}
leaf_nodes.resize(self.num_leaf_nodes(), LeafNode::Padding);
leaf_nodes.resize(n, LeafNode::DoesNotExist);
leaf_nodes
}
pub fn num_leaf_nodes(&self) -> usize {
@ -128,28 +131,6 @@ impl BTreeOverlay {
self.offset + self.num_internal_nodes()
}
/// Returns the chunk-range for a given leaf node.
///
/// Returns `None` if:
/// - The specified node is internal.
/// - The specified node is padding.
/// - The specified node is OOB of the tree.
pub fn get_leaf_node(&self, i: usize) -> Result<LeafNode, Error> {
if i >= self.num_nodes() {
Ok(LeafNode::DoesNotExist)
} else if i >= self.num_nodes() - self.num_padding_leaves() {
Ok(LeafNode::Padding)
} else if (i == self.num_internal_nodes()) && (self.lengths.len() == 0) {
// If this is the first leaf node and the overlay contains zero items, return `None` as
// this node must be padding.
Ok(LeafNode::Padding)
} else {
let i = i - self.num_internal_nodes();
Ok(self.leaf_nodes[i].clone())
}
}
pub fn child_chunks(&self, parent: usize) -> (usize, usize) {
let children = children(parent);
@ -263,33 +244,38 @@ mod test {
#[test]
fn get_leaf_node() {
let tree = get_tree_a(4);
let leaves = tree.get_leaf_nodes(5);
assert_eq!(tree.get_leaf_node(3), Ok(LeafNode::Exists(3..4)));
assert_eq!(tree.get_leaf_node(4), Ok(LeafNode::Exists(4..5)));
assert_eq!(tree.get_leaf_node(5), Ok(LeafNode::Exists(5..6)));
assert_eq!(tree.get_leaf_node(6), Ok(LeafNode::Exists(6..7)));
assert_eq!(tree.get_leaf_node(7), Ok(LeafNode::DoesNotExist));
assert_eq!(leaves[0], LeafNode::Exists(3..4));
assert_eq!(leaves[1], LeafNode::Exists(4..5));
assert_eq!(leaves[2], LeafNode::Exists(5..6));
assert_eq!(leaves[3], LeafNode::Exists(6..7));
assert_eq!(leaves[4], LeafNode::DoesNotExist);
let tree = get_tree_a(3);
let leaves = tree.get_leaf_nodes(5);
assert_eq!(tree.get_leaf_node(3), Ok(LeafNode::Exists(3..4)));
assert_eq!(tree.get_leaf_node(4), Ok(LeafNode::Exists(4..5)));
assert_eq!(tree.get_leaf_node(5), Ok(LeafNode::Exists(5..6)));
assert_eq!(tree.get_leaf_node(6), Ok(LeafNode::Padding));
assert_eq!(tree.get_leaf_node(7), Ok(LeafNode::DoesNotExist));
assert_eq!(leaves[0], LeafNode::Exists(3..4));
assert_eq!(leaves[1], LeafNode::Exists(4..5));
assert_eq!(leaves[2], LeafNode::Exists(5..6));
assert_eq!(leaves[3], LeafNode::Padding);
assert_eq!(leaves[4], LeafNode::DoesNotExist);
let tree = get_tree_a(0);
let leaves = tree.get_leaf_nodes(2);
assert_eq!(tree.get_leaf_node(0), Ok(LeafNode::Padding));
assert_eq!(tree.get_leaf_node(1), Ok(LeafNode::DoesNotExist));
assert_eq!(leaves[0], LeafNode::Padding);
assert_eq!(leaves[1], LeafNode::DoesNotExist);
let tree = BTreeSchema::from_lengths(0, vec![3]).into_overlay(0);
assert_eq!(tree.get_leaf_node(0), Ok(LeafNode::Exists(0..3)));
assert_eq!(tree.get_leaf_node(1), Ok(LeafNode::DoesNotExist));
let leaves = tree.get_leaf_nodes(2);
assert_eq!(leaves[0], LeafNode::Exists(0..3));
assert_eq!(leaves[1], LeafNode::DoesNotExist);
let tree = BTreeSchema::from_lengths(0, vec![3]).into_overlay(10);
assert_eq!(tree.get_leaf_node(0), Ok(LeafNode::Exists(10..13)));
assert_eq!(tree.get_leaf_node(1), Ok(LeafNode::DoesNotExist));
let leaves = tree.get_leaf_nodes(2);
assert_eq!(leaves[0], LeafNode::Exists(10..13));
assert_eq!(leaves[1], LeafNode::DoesNotExist);
}
#[test]

View File

@ -147,11 +147,18 @@ pub fn update_tree_hash_cache<T: CachedTreeHash<T>>(
}
}
TreeHashType::Container | TreeHashType::List | TreeHashType::Vector => {
for i in 0..std::cmp::max(new_overlay.num_leaf_nodes(), old_overlay.num_leaf_nodes()) {
match (
old_overlay.get_leaf_node(i + old_overlay.num_internal_nodes())?,
new_overlay.get_leaf_node(i + new_overlay.num_internal_nodes())?,
) {
let longest_len =
std::cmp::max(new_overlay.num_leaf_nodes(), old_overlay.num_leaf_nodes());
let old_leaf_nodes = old_overlay.get_leaf_nodes(longest_len);
let new_leaf_nodes = if old_overlay == new_overlay {
old_leaf_nodes.clone()
} else {
new_overlay.get_leaf_nodes(longest_len)
};
for i in 0..longest_len {
match (&old_leaf_nodes[i], &new_leaf_nodes[i]) {
// The item existed in the previous list and exists in the current list.
//
// Update the item.