Golang example for debugging a concurrency scenario

gistfile1.txt

package main

import (
	"fmt"
)

type Tree struct {
	Left *Tree
	Value int
	Right *Tree
}

var (
	tree1 = Tree{
		&Tree{
			&Tree{nil, 1, nil},
			1,
			&Tree{nil, 2, nil},
			},
		3,
		&Tree{
			&Tree{nil, 5, nil},
			8,
			&Tree{nil, 13, nil},
			},
		}
	tree2 = Tree{
		&Tree{
			&Tree{
				&Tree{nil, 1, nil},
				1,
				&Tree{nil, 2, nil}},
			3,
			&Tree{nil, 5, nil},
			},
		8,
		&Tree{nil, 13, nil},
		}
	tree3 = Tree{
		&Tree{
			&Tree{
				&Tree{nil, 1, nil},
				1,
				&Tree{nil, 2, nil}},
			3,
			&Tree{nil, 5, nil},
		},
		8,
		&Tree{nil, 14, nil},
	}
)

func Walk(treeName string, tree *Tree, ch chan int) {
	recWalk(treeName, tree, ch)
	close(ch)
}

func recWalk(treeName string, tree *Tree, ch chan int) {
	if tree != nil {
		recWalk(treeName, tree.Left, ch)
		ch <- tree.Value
		if tree.Value == 13 {
			fmt.Println("Here will be a breakpoint")
		}
		recWalk(treeName, tree.Right, ch)
	}
}

func Same(t1, t2 *Tree) bool {
	ch1 := make(chan int)
	ch2 := make(chan int)
	go Walk("tree1", t1, ch1)
	go Walk("tree2", t2, ch2)

	for {
		x1, ok1 := <- ch1
		x2, ok2 := <- ch2
		switch {
		case ok1 != ok2:
			// One channel finishes earlier, so not same size
			return false
		case !ok1:
			// Both channels are empty
			return true
		case x1 != x2:
			// Elements are different
			return false
		default:
		}
	}
}

func main() {
	fmt.Println("Binary Tree exercice")
	fmt.Println(Same(&tree1, &tree2))
	fmt.Println(Same(&tree1, &tree3))
}