| 1 | package a |
|---|---|
| 2 | |
| 3 | type X struct{ f, g int } |
| 4 | |
| 5 | func f(x, y *X) { |
| 6 | if x == nil { |
| 7 | print(x.f) // want "nil dereference in field selection" |
| 8 | } else { |
| 9 | print(x.f) |
| 10 | } |
| 11 | |
| 12 | if x == nil { |
| 13 | if nil != y { |
| 14 | print(1) |
| 15 | panic(0) |
| 16 | } |
| 17 | x.f = 1 // want "nil dereference in field selection" |
| 18 | y.f = 1 // want "nil dereference in field selection" |
| 19 | } |
| 20 | |
| 21 | var f func() |
| 22 | if f == nil { // want "tautological condition: nil == nil" |
| 23 | go f() // want "nil dereference in dynamic function call" |
| 24 | } else { |
| 25 | // This block is unreachable, |
| 26 | // so we don't report an error for the |
| 27 | // nil dereference in the call. |
| 28 | defer f() |
| 29 | } |
| 30 | } |
| 31 | |
| 32 | func f2(ptr *[3]int, i interface{}) { |
| 33 | if ptr != nil { |
| 34 | print(ptr[:]) |
| 35 | *ptr = [3]int{} |
| 36 | print(*ptr) |
| 37 | } else { |
| 38 | print(ptr[:]) // want "nil dereference in slice operation" |
| 39 | *ptr = [3]int{} // want "nil dereference in store" |
| 40 | print(*ptr) // want "nil dereference in load" |
| 41 | |
| 42 | if ptr != nil { // want "impossible condition: nil != nil" |
| 43 | // Dominated by ptr==nil and ptr!=nil, |
| 44 | // this block is unreachable. |
| 45 | // We do not report errors within it. |
| 46 | print(*ptr) |
| 47 | } |
| 48 | } |
| 49 | |
| 50 | if i != nil { |
| 51 | print(i.(interface{ f() })) |
| 52 | } else { |
| 53 | print(i.(interface{ f() })) // want "nil dereference in type assertion" |
| 54 | } |
| 55 | } |
| 56 | |
| 57 | func g() error |
| 58 | |
| 59 | func f3() error { |
| 60 | err := g() |
| 61 | if err != nil { |
| 62 | return err |
| 63 | } |
| 64 | if err != nil && err.Error() == "foo" { // want "impossible condition: nil != nil" |
| 65 | print(0) |
| 66 | } |
| 67 | ch := make(chan int) |
| 68 | if ch == nil { // want "impossible condition: non-nil == nil" |
| 69 | print(0) |
| 70 | } |
| 71 | if ch != nil { // want "tautological condition: non-nil != nil" |
| 72 | print(0) |
| 73 | } |
| 74 | return nil |
| 75 | } |
| 76 | |
| 77 | func h(err error, b bool) { |
| 78 | if err != nil && b { |
| 79 | return |
| 80 | } else if err != nil { |
| 81 | panic(err) |
| 82 | } |
| 83 | } |
| 84 | |
| 85 | func i(*int) error { |
| 86 | for { |
| 87 | if err := g(); err != nil { |
| 88 | return err |
| 89 | } |
| 90 | } |
| 91 | } |
| 92 | |
| 93 | func f4(x *X) { |
| 94 | if x == nil { |
| 95 | panic(x) |
| 96 | } |
| 97 | } |
| 98 | |
| 99 | func f5(x *X) { |
| 100 | panic(nil) // want "panic with nil value" |
| 101 | } |
| 102 | |
| 103 | func f6(x *X) { |
| 104 | var err error |
| 105 | panic(err) // want "panic with nil value" |
| 106 | } |
| 107 | |
| 108 | func f7() { |
| 109 | x, err := bad() |
| 110 | if err != nil { |
| 111 | panic(0) |
| 112 | } |
| 113 | if x == nil { |
| 114 | panic(err) // want "panic with nil value" |
| 115 | } |
| 116 | } |
| 117 | |
| 118 | func bad() (*X, error) { |
| 119 | return nil, nil |
| 120 | } |
| 121 | |
| 122 | func f8() { |
| 123 | var e error |
| 124 | v, _ := e.(interface{}) |
| 125 | print(v) |
| 126 | } |
| 127 | |
| 128 | func f9(x interface { |
| 129 | a() |
| 130 | b() |
| 131 | c() |
| 132 | }) { |
| 133 | x.b() // we don't catch this panic because we don't have any facts yet |
| 134 | xx := interface { |
| 135 | a() |
| 136 | b() |
| 137 | }(x) |
| 138 | if xx != nil { |
| 139 | return |
| 140 | } |
| 141 | x.c() // want "nil dereference in dynamic method call" |
| 142 | xx.b() // want "nil dereference in dynamic method call" |
| 143 | xxx := interface{ a() }(xx) |
| 144 | xxx.a() // want "nil dereference in dynamic method call" |
| 145 | |
| 146 | if unknown() { |
| 147 | panic(x) // want "panic with nil value" |
| 148 | } |
| 149 | if unknown() { |
| 150 | panic(xx) // want "panic with nil value" |
| 151 | } |
| 152 | if unknown() { |
| 153 | panic(xxx) // want "panic with nil value" |
| 154 | } |
| 155 | } |
| 156 | |
| 157 | func f10() { |
| 158 | s0 := make([]string, 0) |
| 159 | if s0 == nil { // want "impossible condition: non-nil == nil" |
| 160 | print(0) |
| 161 | } |
| 162 | |
| 163 | var s1 []string |
| 164 | if s1 == nil { // want "tautological condition: nil == nil" |
| 165 | print(0) |
| 166 | } |
| 167 | s2 := s1[:][:] |
| 168 | if s2 == nil { // want "tautological condition: nil == nil" |
| 169 | print(0) |
| 170 | } |
| 171 | } |
| 172 | |
| 173 | func unknown() bool { |
| 174 | return false |
| 175 | } |
| 176 | |
| 177 | func f11(a interface{}) { |
| 178 | switch a.(type) { |
| 179 | case nil: |
| 180 | return |
| 181 | } |
| 182 | switch a.(type) { |
| 183 | case nil: // want "impossible condition: non-nil == nil" |
| 184 | return |
| 185 | } |
| 186 | } |
| 187 | |
| 188 | func f12(a interface{}) { |
| 189 | switch a { |
| 190 | case nil: |
| 191 | return |
| 192 | } |
| 193 | switch a { |
| 194 | case 5, |
| 195 | nil: // want "impossible condition: non-nil == nil" |
| 196 | return |
| 197 | } |
| 198 | } |
| 199 | |
| 200 | type Y struct { |
| 201 | innerY |
| 202 | } |
| 203 | |
| 204 | type innerY struct { |
| 205 | value int |
| 206 | } |
| 207 | |
| 208 | func f13() { |
| 209 | var d *Y |
| 210 | print(d.value) // want "nil dereference in field selection" |
| 211 | } |
| 212 | |
| 213 | func f14() { |
| 214 | var x struct{ f string } |
| 215 | if x == struct{ f string }{} { // we don't catch this tautology as we restrict to reference types |
| 216 | print(x) |
| 217 | } |
| 218 | } |
| 219 |
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