gods/trees/btree/btree_test.go

// Copyright (c) 2015, Emir Pasic. All rights reserved.
// Use of this source code is governed by a BSD-style
// license that can be found in the LICENSE file.

package btree

import (
	"fmt"
	"testing"
)

func TestBTreeGet1(t *testing.T) {
	tree := NewWithIntComparator(3)
	tree.Put(1, "a")
	tree.Put(2, "b")
	tree.Put(3, "c")
	tree.Put(4, "d")
	tree.Put(5, "e")
	tree.Put(6, "f")
	tree.Put(7, "g")

	tests := [][]interface{}{
		{0, nil, false},
		{1, "a", true},
		{2, "b", true},
		{3, "c", true},
		{4, "d", true},
		{5, "e", true},
		{6, "f", true},
		{7, "g", true},
		{8, nil, false},
	}

	for _, test := range tests {
		if value, found := tree.Get(test[0]); value != test[1] || found != test[2] {
			t.Errorf("Got %v,%v expected %v,%v", value, found, test[1], test[2])
		}
	}
}

func TestBTreeGet2(t *testing.T) {
	//tree := NewWithIntComparator(3)
	//tree.Put(7, "g")
	//tree.Put(9, "i")
	//tree.Put(10, "j")
	//tree.Put(6, "f")
	//tree.Put(3, "c")
	//tree.Put(4, "d")
	//tree.Put(5, "e")
	//tree.Put(8, "h")
	//tree.Put(2, "b")
	////tree.Put(1, "a")
	//fmt.Println(tree)
	//
	//tests := [][]interface{}{
	//	{0, nil, false},
	//	{1, "a", true},
	//	{2, "b", true},
	//	{3, "c", true},
	//	{4, "d", true},
	//	{5, "e", true},
	//	{6, "f", true},
	//	{7, "g", true},
	//	{8, "h", true},
	//	{9, "i", true},
	//	{10, "j", true},
	//	{11, nil, false},
	//}
	//
	//for _, test := range tests {
	//	if value, found := tree.Get(test[0]); value != test[1] || found != test[2] {
	//		t.Errorf("Got %v,%v expected %v,%v", value, found, test[1], test[2])
	//	}
	//}
}

func TestBTreePut1(t *testing.T) {
	// https://upload.wikimedia.org/wikipedia/commons/3/33/B_tree_insertion_example.png
	tree := NewWithIntComparator(3)
	assertValidTree(t, tree, 0)

	tree.Put(1, 0)
	assertValidTree(t, tree, 1)
	assertValidTreeNode(t, tree.Root, 1, 0, []int{1}, false)

	tree.Put(2, 1)
	assertValidTree(t, tree, 2)
	assertValidTreeNode(t, tree.Root, 2, 0, []int{1, 2}, false)

	tree.Put(3, 2)
	assertValidTree(t, tree, 3)
	assertValidTreeNode(t, tree.Root, 1, 2, []int{2}, false)
	assertValidTreeNode(t, tree.Root.Children[0], 1, 0, []int{1}, true)
	assertValidTreeNode(t, tree.Root.Children[1], 1, 0, []int{3}, true)

	tree.Put(4, 2)
	assertValidTree(t, tree, 4)
	assertValidTreeNode(t, tree.Root, 1, 2, []int{2}, false)
	assertValidTreeNode(t, tree.Root.Children[0], 1, 0, []int{1}, true)
	assertValidTreeNode(t, tree.Root.Children[1], 2, 0, []int{3, 4}, true)

	tree.Put(5, 2)
	assertValidTree(t, tree, 5)
	assertValidTreeNode(t, tree.Root, 2, 3, []int{2, 4}, false)
	assertValidTreeNode(t, tree.Root.Children[0], 1, 0, []int{1}, true)
	assertValidTreeNode(t, tree.Root.Children[1], 1, 0, []int{3}, true)
	assertValidTreeNode(t, tree.Root.Children[2], 1, 0, []int{5}, true)

	tree.Put(6, 2)
	assertValidTree(t, tree, 6)
	assertValidTreeNode(t, tree.Root, 2, 3, []int{2, 4}, false)
	assertValidTreeNode(t, tree.Root.Children[0], 1, 0, []int{1}, true)
	assertValidTreeNode(t, tree.Root.Children[1], 1, 0, []int{3}, true)
	assertValidTreeNode(t, tree.Root.Children[2], 2, 0, []int{5, 6}, true)

	tree.Put(7, 2)
	assertValidTree(t, tree, 7)
	assertValidTreeNode(t, tree.Root, 1, 2, []int{4}, false)
	assertValidTreeNode(t, tree.Root.Children[0], 1, 2, []int{2}, true)
	assertValidTreeNode(t, tree.Root.Children[1], 1, 2, []int{6}, true)
	assertValidTreeNode(t, tree.Root.Children[0].Children[0], 1, 0, []int{1}, true)
	assertValidTreeNode(t, tree.Root.Children[0].Children[1], 1, 0, []int{3}, true)
	assertValidTreeNode(t, tree.Root.Children[1].Children[0], 1, 0, []int{5}, true)
	assertValidTreeNode(t, tree.Root.Children[1].Children[1], 1, 0, []int{7}, true)
}

func TestBTreePut2(t *testing.T) {
	tree := NewWithIntComparator(4)
	assertValidTree(t, tree, 0)

	tree.Put(0, 0)
	assertValidTree(t, tree, 1)
	assertValidTreeNode(t, tree.Root, 1, 0, []int{0}, false)

	tree.Put(2, 2)
	assertValidTree(t, tree, 2)
	assertValidTreeNode(t, tree.Root, 2, 0, []int{0, 2}, false)

	tree.Put(1, 1)
	assertValidTree(t, tree, 3)
	assertValidTreeNode(t, tree.Root, 3, 0, []int{0, 1, 2}, false)

	tree.Put(1, 1)
	assertValidTree(t, tree, 3)
	assertValidTreeNode(t, tree.Root, 3, 0, []int{0, 1, 2}, false)

	tree.Put(3, 3)
	assertValidTree(t, tree, 4)
	assertValidTreeNode(t, tree.Root, 1, 2, []int{1}, false)
	assertValidTreeNode(t, tree.Root.Children[0], 1, 0, []int{0}, true)
	assertValidTreeNode(t, tree.Root.Children[1], 2, 0, []int{2, 3}, true)

	tree.Put(4, 4)
	assertValidTree(t, tree, 5)
	assertValidTreeNode(t, tree.Root, 1, 2, []int{1}, false)
	assertValidTreeNode(t, tree.Root.Children[0], 1, 0, []int{0}, true)
	assertValidTreeNode(t, tree.Root.Children[1], 3, 0, []int{2, 3, 4}, true)

	tree.Put(5, 5)
	assertValidTree(t, tree, 6)
	assertValidTreeNode(t, tree.Root, 2, 3, []int{1, 3}, false)
	assertValidTreeNode(t, tree.Root.Children[0], 1, 0, []int{0}, true)
	assertValidTreeNode(t, tree.Root.Children[1], 1, 0, []int{2}, true)
	assertValidTreeNode(t, tree.Root.Children[2], 2, 0, []int{4, 5}, true)
}

func TestBTreePut3(t *testing.T) {
	// http://www.geeksforgeeks.org/b-tree-set-1-insert-2/
	tree := NewWithIntComparator(6)
	assertValidTree(t, tree, 0)

	tree.Put(10, 0)
	assertValidTree(t, tree, 1)
	assertValidTreeNode(t, tree.Root, 1, 0, []int{10}, false)

	tree.Put(20, 1)
	assertValidTree(t, tree, 2)
	assertValidTreeNode(t, tree.Root, 2, 0, []int{10, 20}, false)

	tree.Put(30, 2)
	assertValidTree(t, tree, 3)
	assertValidTreeNode(t, tree.Root, 3, 0, []int{10, 20, 30}, false)

	tree.Put(40, 3)
	assertValidTree(t, tree, 4)
	assertValidTreeNode(t, tree.Root, 4, 0, []int{10, 20, 30, 40}, false)

	tree.Put(50, 4)
	assertValidTree(t, tree, 5)
	assertValidTreeNode(t, tree.Root, 5, 0, []int{10, 20, 30, 40, 50}, false)

	tree.Put(60, 5)
	assertValidTree(t, tree, 6)
	assertValidTreeNode(t, tree.Root, 1, 2, []int{30}, false)
	assertValidTreeNode(t, tree.Root.Children[0], 2, 0, []int{10, 20}, true)
	assertValidTreeNode(t, tree.Root.Children[1], 3, 0, []int{40, 50, 60}, true)

	tree.Put(70, 6)
	assertValidTree(t, tree, 7)
	assertValidTreeNode(t, tree.Root, 1, 2, []int{30}, false)
	assertValidTreeNode(t, tree.Root.Children[0], 2, 0, []int{10, 20}, true)
	assertValidTreeNode(t, tree.Root.Children[1], 4, 0, []int{40, 50, 60, 70}, true)

	tree.Put(80, 7)
	assertValidTree(t, tree, 8)
	assertValidTreeNode(t, tree.Root, 1, 2, []int{30}, false)
	assertValidTreeNode(t, tree.Root.Children[0], 2, 0, []int{10, 20}, true)
	assertValidTreeNode(t, tree.Root.Children[1], 5, 0, []int{40, 50, 60, 70, 80}, true)

	tree.Put(90, 8)
	assertValidTree(t, tree, 9)
	assertValidTreeNode(t, tree.Root, 2, 3, []int{30, 60}, false)
	assertValidTreeNode(t, tree.Root.Children[0], 2, 0, []int{10, 20}, true)
	assertValidTreeNode(t, tree.Root.Children[1], 2, 0, []int{40, 50}, true)
	assertValidTreeNode(t, tree.Root.Children[2], 3, 0, []int{70, 80, 90}, true)
}

func TestBTreePut4(t *testing.T) {
	tree := NewWithIntComparator(3)
	assertValidTree(t, tree, 0)

	tree.Put(6, nil)
	assertValidTree(t, tree, 1)
	assertValidTreeNode(t, tree.Root, 1, 0, []int{6}, false)

	tree.Put(5, nil)
	assertValidTree(t, tree, 2)
	assertValidTreeNode(t, tree.Root, 2, 0, []int{5, 6}, false)

	tree.Put(4, nil)
	assertValidTree(t, tree, 3)
	assertValidTreeNode(t, tree.Root, 1, 2, []int{5}, false)
	assertValidTreeNode(t, tree.Root.Children[0], 1, 0, []int{4}, true)
	assertValidTreeNode(t, tree.Root.Children[1], 1, 0, []int{6}, true)

	tree.Put(3, nil)
	assertValidTreeNode(t, tree.Root, 1, 2, []int{5}, false)
	assertValidTreeNode(t, tree.Root.Children[0], 2, 0, []int{3, 4}, true)
	assertValidTreeNode(t, tree.Root.Children[1], 1, 0, []int{6}, true)

	tree.Put(2, nil)
	assertValidTreeNode(t, tree.Root, 2, 3, []int{3, 5}, false)
	assertValidTreeNode(t, tree.Root.Children[0], 1, 0, []int{2}, true)
	assertValidTreeNode(t, tree.Root.Children[1], 1, 0, []int{4}, true)
	assertValidTreeNode(t, tree.Root.Children[2], 1, 0, []int{6}, true)

	tree.Put(1, nil)
	assertValidTreeNode(t, tree.Root, 2, 3, []int{3, 5}, false)
	assertValidTreeNode(t, tree.Root.Children[0], 2, 0, []int{1, 2}, true)
	assertValidTreeNode(t, tree.Root.Children[1], 1, 0, []int{4}, true)
	assertValidTreeNode(t, tree.Root.Children[2], 1, 0, []int{6}, true)

	tree.Put(0, nil)
	assertValidTreeNode(t, tree.Root, 1, 2, []int{3}, false)
	assertValidTreeNode(t, tree.Root.Children[0], 1, 2, []int{1}, true)
	assertValidTreeNode(t, tree.Root.Children[1], 1, 2, []int{5}, true)
	assertValidTreeNode(t, tree.Root.Children[0].Children[0], 1, 0, []int{0}, true)
	assertValidTreeNode(t, tree.Root.Children[0].Children[1], 1, 0, []int{2}, true)
	assertValidTreeNode(t, tree.Root.Children[1].Children[0], 1, 0, []int{4}, true)
	assertValidTreeNode(t, tree.Root.Children[1].Children[1], 1, 0, []int{6}, true)

	tree.Put(-1, nil)
	assertValidTreeNode(t, tree.Root, 1, 2, []int{3}, false)
	assertValidTreeNode(t, tree.Root.Children[0], 1, 2, []int{1}, true)
	assertValidTreeNode(t, tree.Root.Children[1], 1, 2, []int{5}, true)
	assertValidTreeNode(t, tree.Root.Children[0].Children[0], 2, 0, []int{-1, 0}, true)
	assertValidTreeNode(t, tree.Root.Children[0].Children[1], 1, 0, []int{2}, true)
	assertValidTreeNode(t, tree.Root.Children[1].Children[0], 1, 0, []int{4}, true)
	assertValidTreeNode(t, tree.Root.Children[1].Children[1], 1, 0, []int{6}, true)

	fmt.Println(tree)
	//tree.Put(-2, nil)
	//tree.Put(-3, nil)
	//tree.Put(-4, nil)
	//tree.Put(-5, nil)
	//tree.Put(-6, nil)
	//fmt.Println(tree)
}

func TestBTreeHeight(t *testing.T) {
	tree := NewWithIntComparator(3)
	if actualValue, expectedValue := tree.Height(), 0; actualValue != expectedValue {
		t.Errorf("Got %v expected %v", actualValue, expectedValue)
	}

	tree.Put(1, 0)
	if actualValue, expectedValue := tree.Height(), 1; actualValue != expectedValue {
		t.Errorf("Got %v expected %v", actualValue, expectedValue)
	}

	tree.Put(2, 1)
	if actualValue, expectedValue := tree.Height(), 1; actualValue != expectedValue {
		t.Errorf("Got %v expected %v", actualValue, expectedValue)
	}

	tree.Put(3, 2)
	if actualValue, expectedValue := tree.Height(), 2; actualValue != expectedValue {
		t.Errorf("Got %v expected %v", actualValue, expectedValue)
	}

	tree.Put(4, 2)
	if actualValue, expectedValue := tree.Height(), 2; actualValue != expectedValue {
		t.Errorf("Got %v expected %v", actualValue, expectedValue)
	}

	tree.Put(5, 2)
	if actualValue, expectedValue := tree.Height(), 2; actualValue != expectedValue {
		t.Errorf("Got %v expected %v", actualValue, expectedValue)
	}

	tree.Put(6, 2)
	if actualValue, expectedValue := tree.Height(), 2; actualValue != expectedValue {
		t.Errorf("Got %v expected %v", actualValue, expectedValue)
	}

	tree.Put(7, 2)
	if actualValue, expectedValue := tree.Height(), 3; actualValue != expectedValue {
		t.Errorf("Got %v expected %v", actualValue, expectedValue)
	}
}

func TestBTree_search(t *testing.T) {
	{
		tree := NewWithIntComparator(3)
		tree.Root = &Node{Entries: []*Entry{}, Children: make([]*Node, 0)}
		tests := [][]interface{}{
			{0, 0, false},
		}
		for _, test := range tests {
			index, found := tree.search(tree.Root, test[0])
			if actualValue, expectedValue := index, test[1]; actualValue != expectedValue {
				t.Errorf("Got %v expected %v", actualValue, expectedValue)
			}
			if actualValue, expectedValue := found, test[2]; actualValue != expectedValue {
				t.Errorf("Got %v expected %v", actualValue, expectedValue)
			}
		}
	}
	{
		tree := NewWithIntComparator(3)
		tree.Root = &Node{Entries: []*Entry{{2, 0}, {4, 1}, {6, 2}}, Children: []*Node{}}
		tests := [][]interface{}{
			{0, 0, false},
			{1, 0, false},
			{2, 0, true},
			{3, 1, false},
			{4, 1, true},
			{5, 2, false},
			{6, 2, true},
			{7, 3, false},
		}
		for _, test := range tests {
			index, found := tree.search(tree.Root, test[0])
			if actualValue, expectedValue := index, test[1]; actualValue != expectedValue {
				t.Errorf("Got %v expected %v", actualValue, expectedValue)
			}
			if actualValue, expectedValue := found, test[2]; actualValue != expectedValue {
				t.Errorf("Got %v expected %v", actualValue, expectedValue)
			}
		}
	}
}

func assertValidTree(t *testing.T, tree *Tree, expectedSize int) {
	if actualValue, expectedValue := tree.size, expectedSize; actualValue != expectedValue {
		t.Errorf("Got %v expected %v for tree size", actualValue, expectedValue)
	}
}

func assertValidTreeNode(t *testing.T, node *Node, expectedEntries int, expectedChildren int, keys []int, hasParent bool) {
	if actualValue, expectedValue := node.Parent != nil, hasParent; actualValue != expectedValue {
		t.Errorf("Got %v expected %v for hasParent", actualValue, expectedValue)
	}
	if actualValue, expectedValue := len(node.Entries), expectedEntries; actualValue != expectedValue {
		t.Errorf("Got %v expected %v for entries size", actualValue, expectedValue)
	}
	if actualValue, expectedValue := len(node.Children), expectedChildren; actualValue != expectedValue {
		t.Errorf("Got %v expected %v for children size", actualValue, expectedValue)
	}
	for i, key := range keys {
		if actualValue, expectedValue := node.Entries[i].Key, key; actualValue != expectedValue {
			t.Errorf("Got %v expected %v for key", actualValue, expectedValue)
		}
	}
}

func BenchmarkBTree(b *testing.B) {
	for i := 0; i < b.N; i++ {
		tree := NewWithIntComparator(32)
		for n := 0; n < 1000; n++ {
			tree.Put(n, n)
		}
		for n := 0; n < 1000; n++ {
			tree.Remove(n)
		}
	}
}