swarm/network/priorotyqueue: add tests and fix Run

swarm/network/priorityqueue/priorityqueue.go

@@ -43,9 +43,9 @@ func New(n int, l int) *PriorityQueue {
 func (pq *PriorityQueue) Run(ctx context.Context, f func(interface{})) {
 	top := len(pq.queues) - 1
 	p := top
-	q := pq.queues[p]
 READ:
 	for {
+		q := pq.queues[p]
 		select {
 		case <-ctx.Done():
 			return

swarm/network/priorityqueue/priorityqueue_test.go

@@ -0,0 +1,82 @@
+package priorityqueue
+
+import (
+	"context"
+	"sync"
+	"testing"
+)
+
+func Test(t *testing.T) {
+	var results []string
+	wg := sync.WaitGroup{}
+	pq := New(3, 2)
+	wg.Add(1)
+	go pq.Run(context.Background(), func(v interface{}) {
+		results = append(results, v.(string))
+		wg.Done()
+	})
+	pq.Push(context.Background(), "2.0", 2)
+	wg.Wait()
+	if results[0] != "2.0" {
+		t.Errorf("expected first result %q, got %q", "2.0", results[0])
+	}
+
+Loop:
+	for i, tc := range []struct {
+		priorities []int
+		values     []string
+		results    []string
+		errors     []error
+	}{
+		{
+			priorities: []int{0},
+			values:     []string{""},
+			results:    []string{""},
+		},
+		{
+			priorities: []int{0, 1},
+			values:     []string{"0.0", "1.0"},
+			results:    []string{"1.0", "0.0"},
+		},
+		{
+			priorities: []int{1, 0},
+			values:     []string{"1.0", "0.0"},
+			results:    []string{"1.0", "0.0"},
+		},
+		{
+			priorities: []int{0, 1, 1},
+			values:     []string{"0.0", "1.0", "1.1"},
+			results:    []string{"1.0", "1.1", "0.0"},
+		},
+		{
+			priorities: []int{0, 0, 0},
+			values:     []string{"0.0", "0.0", "0.1"},
+			errors:     []error{nil, nil, errContention},
+		},
+	} {
+		var results []string
+		wg := sync.WaitGroup{}
+		pq := New(3, 2)
+		wg.Add(len(tc.values))
+		for j, value := range tc.values {
+			err := pq.Push(nil, value, tc.priorities[j])
+			if tc.errors != nil && err != tc.errors[j] {
+				t.Errorf("expected push error %v, got %v", tc.errors[j], err)
+				continue Loop
+			}
+			if err != nil {
+				continue Loop
+			}
+		}
+		go pq.Run(context.Background(), func(v interface{}) {
+			results = append(results, v.(string))
+			wg.Done()
+		})
+		wg.Wait()
+		for k, result := range tc.results {
+			if results[k] != result {
+				t.Errorf("test case %v: expected %v element %q, got %q", i, k, result, results[k])
+			}
+		}
+	}
+}