/
nonamedreturns_custom.go
225 lines (198 loc) · 3.7 KB
/
nonamedreturns_custom.go
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
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
// args: -Enonamedreturns
// config: linters-settings.nonamedreturns.allow-error-in-defer=true
package testdata
func simple() (err error) {
defer func() {
err = nil
}()
return
}
func twoReturnParams() (i int, err error) { // ERROR `named return "i" with type "int" found`
defer func() {
i = 0
err = nil
}()
return
}
func allUnderscoresExceptError() (_ int, err error) {
defer func() {
err = nil
}()
return
}
func customName() (myName error) {
defer func() {
myName = nil
}()
return
}
func errorIsNoAssigned() (err error) { // ERROR `named return "err" with type "error" found`
defer func() {
_ = err
processError(err)
if err == nil {
}
switch err {
case nil:
default:
}
}()
return
}
func shadowVariable() (err error) {
defer func() {
err := 123 // linter doesn't understand that this is different variable (even if different type) (yet?)
_ = err
}()
return
}
func shadowVariable2() (err error) {
defer func() {
a, err := doSomething() // linter doesn't understand that this is different variable (yet?)
_ = a
_ = err
}()
return
}
type myError = error // linter doesn't understand that this is the same type (yet?)
func customType() (err myError) { // ERROR `named return "err" with type "myError" found`
defer func() {
err = nil
}()
return
}
func notTheLast() (err error, _ int) {
defer func() {
err = nil
}()
return
}
func twoErrorsCombined() (err1, err2 error) {
defer func() {
err1 = nil
err2 = nil
}()
return
}
func twoErrorsSeparated() (err1 error, err2 error) {
defer func() {
err1 = nil
err2 = nil
}()
return
}
func errorSlice() (err []error) { // ERROR `named return "err" with type "\[\]error" found`
defer func() {
err = nil
}()
return
}
func deferWithVariable() (err error) { // ERROR `named return "err" with type "error" found`
f := func() {
err = nil
}
defer f() // linter can't catch closure passed via variable (yet?)
return
}
func uberMultierr() (err error) { // ERROR `named return "err" with type "error" found`
defer func() {
multierrAppendInto(&err, nil) // linter doesn't allow it (yet?)
}()
return
}
func deferInDefer() (err error) {
defer func() {
defer func() {
err = nil
}()
}()
return
}
func twoDefers() (err error) {
defer func() {}()
defer func() {
err = nil
}()
return
}
func callFunction() (err error) {
defer func() {
_, err = doSomething()
}()
return
}
func callFunction2() (err error) {
defer func() {
var a int
a, err = doSomething()
_ = a
}()
return
}
func deepInside() (err error) {
if true {
switch true {
case false:
for i := 0; i < 10; i++ {
go func() {
select {
default:
defer func() {
if true {
switch true {
case false:
for j := 0; j < 10; j++ {
go func() {
select {
default:
err = nil
}
}()
}
}
}
}()
}
}()
}
}
}
return
}
var goodFuncLiteral = func() (err error) {
defer func() {
err = nil
}()
return
}
var badFuncLiteral = func() (err error) { // ERROR `named return "err" with type "error" found`
defer func() {
_ = err
}()
return
}
func funcLiteralInsideFunc() error {
do := func() (err error) {
defer func() {
err = nil
}()
return
}
return do()
}
type x struct{}
func (x) goodMethod() (err error) {
defer func() {
err = nil
}()
return
}
func (x) badMethod() (err error) { // ERROR `named return "err" with type "error" found`
defer func() {
_ = err
}()
return
}
func processError(error) {}
func doSomething() (int, error) { return 10, nil }
func multierrAppendInto(*error, error) bool { return false } // https://pkg.go.dev/go.uber.org/multierr#AppendInto