AncestorsWalker panics if we try to stop at the last vertex #37
Description
Reproduction based on the original usage example, but modifying the exit criteria:
package main
import (
"fmt"
"github.com/heimdalr/dag"
)
func main() {
dag := dag.NewDAG()
v1, _ := dag.AddVertex("1")
v2, _ := dag.AddVertex("2")
v3, _ := dag.AddVertex("3")
v4, _ := dag.AddVertex("4")
v5, _ := dag.AddVertex("5")
_ = dag.AddEdge(v1, v2)
_ = dag.AddEdge(v2, v3)
_ = dag.AddEdge(v2, v4)
_ = dag.AddEdge(v4, v5)
var ancestors []interface{}
vertices, signal, _ := dag.AncestorsWalker(v5)
for v := range vertices {
ancestors = append(ancestors, v)
// v2 was modified to v1
if v == v1 {
signal <- true
break
}
}
fmt.Printf("%v", ancestors)
}
Results in
panic: send on closed channel
I'm happy to contribute, but I'm not quite sure how to resolve this while maintaining the current API contract.