u

data-structure/ds-queue_test.go

@@ -0,0 +1,61 @@
+package ds
+
+import "testing"
+
+func TestQueueFIFO(t *testing.T) {
+	var q Queue[int]
+	if !q.Empty() {
+		t.Fatal("新建队列应为空")
+	}
+	if _, ok := q.Dequeue(); ok {
+		t.Fatal("空队列 Dequeue 应返回 false")
+	}
+
+	q.Enqueue(1)
+	q.Enqueue(2)
+	q.Enqueue(3)
+	if q.Len() != 3 {
+		t.Fatalf("Len = %d, want 3", q.Len())
+	}
+
+	// FIFO 顺序
+	for _, want := range []int{1, 2, 3} {
+		got, ok := q.Dequeue()
+		if !ok {
+			t.Fatalf("Dequeue 失败,期望 %d", want)
+		}
+		if got != want {
+			t.Fatalf("Dequeue = %d, want %d", got, want)
+		}
+	}
+	if !q.Empty() {
+		t.Fatal("全部出队后应为空")
+	}
+}
+
+func TestQueueFront(t *testing.T) {
+	var q Queue[string]
+	q.Enqueue("x")
+	q.Enqueue("y")
+	f, ok := q.Front()
+	if !ok || f != "x" {
+		t.Fatalf("Front = %q,%v, want \"x\",true", f, ok)
+	}
+	_, _ = q.Dequeue()
+	f, _ = q.Front()
+	if f != "y" {
+		t.Fatalf("第二次 Front = %q, want \"y\"", f)
+	}
+}
+
+func TestQueueCompactNoGrowth(t *testing.T) {
+	// 大量入队/出队后,逻辑长度正确且不泄漏内存。
+	var q Queue[int]
+	for i := 0; i < 1000; i++ {
+		q.Enqueue(i)
+		_, _ = q.Dequeue()
+	}
+	if !q.Empty() {
+		t.Fatal("1000 次入队+出队后应为空")
+	}
+}