aboutsummaryrefslogtreecommitdiff
path: root/go/analysis/passes/nilness/testdata/src/a/a.go
blob: f4d8f455eff0f6d29f028095d5de744198eb3a0c (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
package a

type X struct{ f, g int }

func f(x, y *X) {
	if x == nil {
		print(x.f) // want "nil dereference in field selection"
	} else {
		print(x.f)
	}

	if x == nil {
		if nil != y {
			print(1)
			panic(0)
		}
		x.f = 1 // want "nil dereference in field selection"
		y.f = 1 // want "nil dereference in field selection"
	}

	var f func()
	if f == nil { // want "tautological condition: nil == nil"
		go f() // want "nil dereference in dynamic function call"
	} else {
		// This block is unreachable,
		// so we don't report an error for the
		// nil dereference in the call.
		defer f()
	}
}

func f2(ptr *[3]int, i interface{}) {
	if ptr != nil {
		print(ptr[:])
		*ptr = [3]int{}
		print(*ptr)
	} else {
		print(ptr[:])   // want "nil dereference in slice operation"
		*ptr = [3]int{} // want "nil dereference in store"
		print(*ptr)     // want "nil dereference in load"

		if ptr != nil { // want "impossible condition: nil != nil"
			// Dominated by ptr==nil and ptr!=nil,
			// this block is unreachable.
			// We do not report errors within it.
			print(*ptr)
		}
	}

	if i != nil {
		print(i.(interface{ f() }))
	} else {
		print(i.(interface{ f() })) // want "nil dereference in type assertion"
	}
}

func g() error

func f3() error {
	err := g()
	if err != nil {
		return err
	}
	if err != nil && err.Error() == "foo" { // want "impossible condition: nil != nil"
		print(0)
	}
	ch := make(chan int)
	if ch == nil { // want "impossible condition: non-nil == nil"
		print(0)
	}
	if ch != nil { // want "tautological condition: non-nil != nil"
		print(0)
	}
	return nil
}

func h(err error, b bool) {
	if err != nil && b {
		return
	} else if err != nil {
		panic(err)
	}
}

func i(*int) error {
	for {
		if err := g(); err != nil {
			return err
		}
	}
}

func f4(x *X) {
	if x == nil {
		panic(x)
	}
}

func f5(x *X) {
	panic(nil) // want "panic with nil value"
}

func f6(x *X) {
	var err error
	panic(err) // want "panic with nil value"
}

func f7() {
	x, err := bad()
	if err != nil {
		panic(0)
	}
	if x == nil {
		panic(err) // want "panic with nil value"
	}
}

func bad() (*X, error) {
	return nil, nil
}

func f8() {
	var e error
	v, _ := e.(interface{})
	print(v)
}

func f9(x interface {
	a()
	b()
	c()
}) {

	x.b() // we don't catch this panic because we don't have any facts yet
	xx := interface {
		a()
		b()
	}(x)
	if xx != nil {
		return
	}
	x.c()  // want "nil dereference in dynamic method call"
	xx.b() // want "nil dereference in dynamic method call"
	xxx := interface{ a() }(xx)
	xxx.a() // want "nil dereference in dynamic method call"

	if unknown() {
		panic(x) // want "panic with nil value"
	}
	if unknown() {
		panic(xx) // want "panic with nil value"
	}
	if unknown() {
		panic(xxx) // want "panic with nil value"
	}
}

func unknown() bool {
	return false
}

func f10(a interface{}) {
	switch a.(type) {
	case nil:
		return
	}
	switch a.(type) {
	case nil: // want "impossible condition: non-nil == nil"
		return
	}
}

func f11(a interface{}) {
	switch a {
	case nil:
		return
	}
	switch a {
	case 5,
		nil: // want "impossible condition: non-nil == nil"
		return
	}
}