Added tests for xifo

xifo/xifo_test.go

@@ -0,0 +1,127 @@
+package xifo_test
+
+import (
+	"github.com/gonum/graph/xifo"
+	"testing"
+)
+
+func TestStack(t *testing.T) {
+	testStack(&xifo.GonumStack{}, t)
+}
+
+func testStack(stack xifo.Stack, t *testing.T) {
+
+	stack.Push(5)
+	if stack.IsEmpty() {
+		t.Error("Stack is empty after push")
+	}
+
+	if i, ok := stack.PeekLast().(int); !ok {
+		t.Error("Stack peek does not return element of correct type")
+	} else if i != 5 {
+		t.Error("Stack peek does not return element of correct value")
+	}
+
+	if stack.IsEmpty() {
+		t.Fatal("Stack peek destroys element")
+	}
+
+	if i, ok := stack.Pop().(int); !ok {
+		t.Error("Stack pop does not return element of correct type")
+	} else if i != 5 {
+		t.Error("Stack pop does not return element of correct value")
+	}
+
+	if !stack.IsEmpty() {
+		t.Fatal("Stack is not empty after popping last element")
+	}
+
+	for i := 0; i <= 10; i++ {
+		stack.Push(i)
+	}
+
+	for i := 10; i >= 0; i-- {
+		j := stack.Pop().(int)
+		if j == (10-i) && i != 5 {
+			t.Errorf("Stack is FIFO; stack value: %d; expected: %d", j, i)
+		} else if j != i {
+			t.Errorf("Stack returned strange element on LIFO test; stack value: %d; expected: %d", j, i)
+		}
+	}
+
+	if !stack.IsEmpty() {
+		t.Fatal("Stack is not empty after popping last element")
+	}
+
+	defer func() {
+		err := recover()
+		if err == nil {
+			t.Error("Stack did not properly panic when popping an empty one")
+		}
+	}()
+
+	stack.Pop()
+}
+
+func TestQueue(t *testing.T) {
+	testQueue(&xifo.GonumQueue{}, t)
+}
+
+func testQueue(queue xifo.Queue, t *testing.T) {
+
+	queue.Push(5)
+	if queue.IsEmpty() {
+		t.Error("Queue is empty after push")
+	}
+
+	if i, ok := queue.PeekFirst().(int); !ok {
+		t.Error("Queue peek does not return element of correct type")
+	} else if i != 5 {
+		t.Error("Queue peek does not return element of correct value")
+	}
+
+	if queue.IsEmpty() {
+		t.Fatal("Queue peek destroys element")
+	}
+
+	if i, ok := queue.Poll().(int); !ok {
+		t.Error("Queue poll does not return element of correct type (or peek mutates it)")
+	} else if i != 5 {
+		t.Error("Queue poll does not return element of correct value (or peek mutates it)")
+	}
+
+	if !queue.IsEmpty() {
+		t.Fatal("Queue is not empty after polling last element")
+	}
+
+	for i := 0; i <= 10; i++ {
+		queue.Push(i)
+	}
+
+	for i := 0; i <= 10; i++ {
+		j := queue.Poll().(int)
+		if j == (10-i) && i != 5 {
+			t.Errorf("Queue is LIFO; queue value: %d; expected: %d", j, i)
+		} else if j != i {
+			t.Errorf("Queue returned strange element on FIFO test; queue value: %d; expected: %d", j, i)
+		}
+	}
+
+	if !queue.IsEmpty() {
+		t.Fatal("Queue is not empty after popping last element")
+	}
+
+	defer func() {
+		err := recover()
+		if err == nil {
+			t.Error("Queue did not properly panic when polling an empty one")
+		}
+	}()
+
+	queue.Poll()
+}
+
+func TestDeque(t *testing.T) {
+	testStack(&xifo.GonumDeque{}, t)
+	testQueue(&xifo.GonumDeque{}, t)
+}