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package types
import (
"fmt"
"strings"
"testing"
)
func genFakeTree() *Thread {
tree := &Thread{
Uid: 0,
}
var prevChild *Thread
for i := 1; i < 3; i++ {
child := &Thread{
Uid: uint32(i * 10),
Parent: tree,
PrevSibling: prevChild,
}
if prevChild != nil {
prevChild.NextSibling = child
} else if tree.FirstChild == nil {
tree.FirstChild = child
} else {
panic("unreachable")
}
prevChild = child
var prevSecond *Thread
for j := 1; j < 3; j++ {
second := &Thread{
Uid: child.Uid + uint32(j),
Parent: child,
PrevSibling: prevSecond,
}
if prevSecond != nil {
prevSecond.NextSibling = second
} else if child.FirstChild == nil {
child.FirstChild = second
} else {
panic("unreachable")
}
prevSecond = second
var prevThird *Thread
limit := 3
if j == 2 {
limit = 8
}
for k := 1; k < limit; k++ {
third := &Thread{
Uid: second.Uid*10 + uint32(k),
Parent: second,
PrevSibling: prevThird,
}
if prevThird != nil {
prevThird.NextSibling = third
} else if second.FirstChild == nil {
second.FirstChild = third
} else {
panic("unreachable")
}
prevThird = third
}
}
}
return tree
}
func TestNewWalk(t *testing.T) {
tree := genFakeTree()
var prefix []string
lastLevel := 0
tree.Walk(func(t *Thread, lvl int, e error) error {
// if t.Uid%2 != 0 {
// return ErrSkipThread
// }
if e != nil {
fmt.Printf("ERROR: %v\n", e)
}
if lvl > lastLevel && lvl > 1 {
// we actually just descended... so figure out what connector we need
// level 1 is flush to the root, so we avoid the indentation there
if t.Parent.NextSibling != nil {
prefix = append(prefix, "│ ")
} else {
prefix = append(prefix, " ")
}
} else if lvl < lastLevel {
//ascended, need to trim the prefix layers
diff := lastLevel - lvl
prefix = prefix[:len(prefix)-diff]
}
var arrow string
if t.Parent != nil {
if t.NextSibling != nil {
arrow = "├─>"
} else {
arrow = "└─>"
}
}
// format
fmt.Printf("%s%s%s\n", strings.Join(prefix, ""), arrow, t)
lastLevel = lvl
return nil
})
}
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