新增remove方法用来，删除并返回删除元素

Author: ybq

cache.go

@@ -911,6 +911,23 @@ func (c *cache) Delete(k string) {
 	}
 }
 
+// Remove an item from the cache. Does nothing if the key is not in the cache.
+// There is delete cache data, return cache data and presence status
+func (c *cache) Remove(k string) (interface{}, bool) {
+	c.mu.Lock()
+	v, found := c.items[k]
+	if found {
+		delete(c.items, k)
+		c.mu.Unlock()
+		if c.onEvicted != nil {
+			c.onEvicted(k, v)
+		}
+		return v.Object, true
+	}
+	c.mu.Unlock()
+	return nil, false
+}
+
 func (c *cache) delete(k string) (interface{}, bool) {
 	if c.onEvicted != nil {
 		if v, found := c.items[k]; found {

cache_test.go

@@ -1149,7 +1149,25 @@ func TestDelete(t *testing.T) {
 		t.Error("x is not nil:", x)
 	}
 }
+func TestREmove(t *testing.T) {
+	tc := New(DefaultExpiration, 0)
+	tc.Set("foo", "bar", DefaultExpiration)
+	data, ok := tc.Remove("foo")
+	if !ok {
+		t.Error("foo was not found, It should be discovered")
+	}
+	if data != "bar" {
+		t.Error("foo should be bar ")
+	}
 
+	x, found := tc.Get("foo")
+	if found {
+		t.Error("foo was found, but it should have been deleted")
+	}
+	if x != nil {
+		t.Error("x is not nil:", x)
+	}
+}
 func TestItemCount(t *testing.T) {
 	tc := New(DefaultExpiration, 0)
 	tc.Set("foo", "1", DefaultExpiration)