Checking for impossible return value from a builtin function GO-W5007
Bug risk
Major
12 days ago
—
a year old
builtin function len does not return negative values
96 fmt.Printf("err: %+v\n", err)
97 return "", true
98 }
99 if len(ips) < 0 {100 fmt.Printf("no ip found for: %s\n", router)
101 return "", true
102 }
Description
Return values of the len and cap builtins cannot be negative.
Bad practice
func foo(slice []int) {
if len(slice) < 0 {
fmt.Println("unreachable code")
}
}
Recommended
func foo(slice []int) {
if len(slice) == 0 {
// Empty slice
}
}