terraform/dag/tarjan_test.go

86 lines
1.6 KiB
Go

package dag
import (
"bytes"
"fmt"
"strings"
"testing"
)
func TestGraphStronglyConnected(t *testing.T) {
var g Graph
g.Add(1)
g.Add(2)
g.Connect(BasicEdge(1, 2))
g.Connect(BasicEdge(2, 1))
actual := strings.TrimSpace(testSCCStr(StronglyConnected(&g)))
expected := strings.TrimSpace(testGraphStronglyConnectedStr)
if actual != expected {
t.Fatalf("bad: %s", actual)
}
}
func TestGraphStronglyConnected_two(t *testing.T) {
var g Graph
g.Add(1)
g.Add(2)
g.Connect(BasicEdge(1, 2))
g.Connect(BasicEdge(2, 1))
g.Add(3)
actual := strings.TrimSpace(testSCCStr(StronglyConnected(&g)))
expected := strings.TrimSpace(testGraphStronglyConnectedTwoStr)
if actual != expected {
t.Fatalf("bad: %s", actual)
}
}
func TestGraphStronglyConnected_three(t *testing.T) {
var g Graph
g.Add(1)
g.Add(2)
g.Connect(BasicEdge(1, 2))
g.Connect(BasicEdge(2, 1))
g.Add(3)
g.Add(4)
g.Add(5)
g.Add(6)
g.Connect(BasicEdge(4, 5))
g.Connect(BasicEdge(5, 6))
g.Connect(BasicEdge(6, 4))
actual := strings.TrimSpace(testSCCStr(StronglyConnected(&g)))
expected := strings.TrimSpace(testGraphStronglyConnectedThreeStr)
if actual != expected {
t.Fatalf("bad: %s", actual)
}
}
func testSCCStr(list [][]Vertex) string {
var buf bytes.Buffer
for _, vs := range list {
result := make([]string, len(vs))
for i, v := range vs {
result[i] = vertName(v)
}
buf.WriteString(fmt.Sprintf("%s\n", strings.Join(result, ",")))
}
return buf.String()
}
const testGraphStronglyConnectedStr = `2,1`
const testGraphStronglyConnectedTwoStr = `
2,1
3
`
const testGraphStronglyConnectedThreeStr = `
2,1
3
6,5,4
`