package hudson.util;
import hudson.util.CyclicGraphDetector.CycleDetectedException;
import junit.framework.TestCase;
import java.util.ArrayList;
import java.util.Arrays;
import java.util.LinkedHashSet;
import java.util.Set;
/**
* @author Kohsuke Kawaguchi
*/
public class CyclicGraphDetectorTest extends TestCase {
private class Edge {
String src,dst;
private Edge(String src, String dst) {
this.src = src;
this.dst = dst;
}
}
private class Graph extends ArrayList<Edge> {
Graph e(String src, String dst) {
add(new Edge(src,dst));
return this;
}
Set<String> nodes() {
Set<String> nodes = new LinkedHashSet<String>();
for (Edge e : this) {
nodes.add(e.src);
nodes.add(e.dst);
}
return nodes;
}
Set<String> edges(String from) {
Set<String> edges = new LinkedHashSet<String>();
for (Edge e : this) {
if (e.src.equals(from))
edges.add(e.dst);
}
return edges;
}
/**
* Performs a cycle check.
*/
void check() throws Exception {
new CyclicGraphDetector<String>() {
protected Set<String> getEdges(String s) {
return edges(s);
}
}.run(nodes());
}
void mustContainCycle(String... members) throws Exception {
try {
check();
fail("Cycle expected");
} catch (CycleDetectedException e) {
String msg = "Expected cycle of " + Arrays.asList(members) + " but found " + e.cycle;
for (String s : members)
assertTrue(msg, e.cycle.contains(s));
}
}
}
public void testCycle() throws Exception {
new Graph().e("A","B").e("B","C").e("C","A").mustContainCycle("A","B","C");
}
public void testCycle2() throws Exception {
new Graph().e("A","B").e("B","C").e("C","C").mustContainCycle("C");
}
public void testCycle3() throws Exception {
new Graph().e("A","B").e("B","C").e("C","D").e("B","E").e("E","D").e("E","A").mustContainCycle("A","B","E");
}
}