github.com/amarpal/go-tools@v0.0.0-20240422043104-40142f59f616/simple/s1009/testdata/src/example.com/CheckRedundantNilCheckWithLen/nil-len.go (about)

     1  package pkg
     2  
     3  func fn() {
     4  	var pa *[5]int
     5  	var s []int
     6  	var m map[int]int
     7  	var ch chan int
     8  
     9  	if s == nil || len(s) == 0 { //@ diag(`should omit nil check`)
    10  	}
    11  	if m == nil || len(m) == 0 { //@ diag(`should omit nil check`)
    12  	}
    13  	if ch == nil || len(ch) == 0 { //@ diag(`should omit nil check`)
    14  	}
    15  
    16  	if s != nil && len(s) != 0 { //@ diag(`should omit nil check`)
    17  	}
    18  	if m != nil && len(m) > 0 { //@ diag(`should omit nil check`)
    19  	}
    20  	if s != nil && len(s) > 5 { //@ diag(`should omit nil check`)
    21  	}
    22  	if s != nil && len(s) >= 5 { //@ diag(`should omit nil check`)
    23  	}
    24  	const five = 5
    25  	if s != nil && len(s) == five { //@ diag(`should omit nil check`)
    26  	}
    27  
    28  	if ch != nil && len(ch) == 5 { //@ diag(`should omit nil check`)
    29  	}
    30  
    31  	if pa == nil || len(pa) == 0 { // nil check cannot be removed with pointer to an array
    32  	}
    33  	if s == nil || len(m) == 0 { // different variables
    34  	}
    35  	if s != nil && len(m) == 1 { // different variables
    36  	}
    37  
    38  	var ch2 chan int
    39  	if ch == ch2 || len(ch) == 0 { // not comparing with nil
    40  	}
    41  	if ch != ch2 && len(ch) != 0 { // not comparing with nil
    42  	}
    43  
    44  	const zero = 0
    45  	if s != nil && len(s) == zero { // nil check is not redundant here
    46  	}
    47  	if s != nil && len(s) == 0 { // nil check is not redundant here
    48  	}
    49  	if s != nil && len(s) >= 0 { // nil check is not redundant here (though len(s) >= 0 is)
    50  	}
    51  	one := 1
    52  	if s != nil && len(s) == one { // nil check is not redundant here
    53  	}
    54  	if s != nil && len(s) == len(m) { // nil check is not redundant here
    55  	}
    56  	if s != nil && len(s) != 1 { // nil check is not redundant here
    57  	}
    58  	if s != nil && len(s) < 5 { // nil check is not redundant here
    59  	}
    60  	if s != nil && len(s) <= 5 { // nil check is not redundant here
    61  	}
    62  	if s != nil && len(s) != len(ch) { // nil check is not redundant here
    63  	}
    64  }
    65  
    66  func fn3() {
    67  	var x []int
    68  
    69  	if x == nil || len(x) == 0 { //@ diag(`should omit nil check`)
    70  	}
    71  
    72  	len := func([]int) int { return 10 }
    73  	if x == nil || len(x) == 0 {
    74  	}
    75  }