updated random function to give value between range

random_math.go

@@ -38,9 +38,9 @@ func RandText(size int, sourceChars string) string {
 	return string(text)
 }
 
-//Random get random in min between max. 生成指定大小的随机数.
-func random(min int64, max int64) float64 {
-	return rand.Float64()*float64(max) - float64(min)
+//Random get random number between min and max. 生成指定大小的随机数.
+func Random(min int64, max int64) float64 {
+	return float64(min) + rand.Float64()*float64(max-min)
 }
 
 //RandDeepColor get random deep color. 随机生成深色系.

random_math_test.go

@@ -30,3 +30,29 @@ func TestRandText(t *testing.T) {
 		})
 	}
 }
+
+func TestRandom(t *testing.T) {
+	type args struct {
+		min int64
+		max int64
+	}
+	tests := []struct {
+		name string
+		args args
+	}{
+		{"", args{-10, 10}},
+		{"", args{-1, 5}},
+		{"", args{0, 15}},
+		{"", args{10, 14}},
+		{"", args{10, 10}},
+	}
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			got := Random(tt.args.min, tt.args.max)
+			// if out of bound then error
+			if got < float64(tt.args.min) || got > float64(tt.args.max) {
+				t.Errorf("RandText() = %v, out of range", got)
+			}
+		})
+	}
+}