fix: GCDSlice returns 1 when slice is empty

Signed-off-by: lowzj <[email protected]>

Author: lowzj

dfget/config/supernode_value.go

@@ -152,7 +152,7 @@ func ParseNodesSlice(value []string) ([]*NodeWeight, error) {
 	for _, v := range nodeWeightSlice {
 		result = append(result, &NodeWeight{
 			Node:   v.Node,
-			Weight: (v.Weight / gcdNumber),
+			Weight: v.Weight / gcdNumber,
 		})
 	}
 

pkg/algorithm/algorithm.go

@@ -17,8 +17,13 @@
 package algorithm
 
 // GCDSlice returns the greatest common divisor of a slice.
+// It returns 1 when s is empty because that any number divided by 1 is still
+// itself.
 func GCDSlice(s []int) int {
 	length := len(s)
+	if length == 0 {
+		return 1
+	}
 	if length == 1 {
 		return s[0]
 	}

pkg/algorithm/algorithm_test.go

@@ -53,6 +53,8 @@ func (suit *AlgorithmSuite) TestGCDSlice() {
 		slice  []int
 		result int
 	}{
+		{nil, 1},
+		{[]int{2}, 2},
 		{[]int{2, 2, 4}, 2},
 		{[]int{5, 10, 25}, 5},
 		{[]int{1, 3, 5}, 1},