scopelint checks for unpinned variables in go programs.
Use looppointer or exportloopref instead.
If you want to find lints as nervous as possible (with some false-positives), you should use looppointer.
If you want to find lints as accurately as possible (with some lints ignored), you should use exportloopref.
Sample problem code from: https://github.com/kyoh86/scopelint/blob/master/example/readme.go
6 values := []string{"a", "b", "c"}
7 var funcs []func()
8 for _, val := range values {
9 funcs = append(funcs, func() {
10 fmt.Println(val)
11 })
12 }
13 for _, f := range funcs {
14 f()
15 }
16 /*output:
17 c
18 c
19 c
20 */
21 var copies []*string
22 for _, val := range values {
23 copies = append(copies, &val)
24 }
25 /*(in copies)
26 &"c"
27 &"c"
28 &"c"
29 */
In Go, the val variable in the above loops is actually a single variable.
So in many case (like the above), using it makes for us annoying bugs.
You can find them with scopelint, and fix it.
$ scopelint ./example/readme.go
example/readme.go:10:16: Using the variable on range scope "val" in function literal
example/readme.go:23:28: Using a reference for the variable on range scope "val"
Found 2 lint problems; failing.
(Fixed sample):
values := []string{"a", "b", "c"}
var funcs []func()
for _, val := range values {
val := val // pin!
funcs = append(funcs, func() {
fmt.Println(val)
})
}
for _, <
8000
span class="pl-s1">f := range funcs {
f()
}
var copies []*string
for _, val := range values {
val := val // pin!
copies = append(copies, &val)
}go get -u github.com/kyoh86/scopelint
Give the package paths of interest as arguments:
scopelint github.com/kyoh86/scopelint/example
To check all packages recursively in the current directory:
scopelint ./...
And also, scopelint supports the following options:
- The
--set-exit-statusflag makes it to set exit status to 1 if any problem variables are found (if you DO NOT it, set --no-set-exit-status) - The
--vendorflag enables checking in thevendordirectories (if you DO NOT it, set--no-vendorflag) - The
--testflag enables checking in the*_test.gofiles" (if you DO NOT it, set--no-testflag)
To ignore issues from use an option comment like //scopelint:ignore. For example, if it's used inline (not from the beginning of the line), it ignores issues only for the line.
var copies []*string
for _, val := range values {
copies = append(copies, &val) //scopelint:ignore
}To ignore issues for the block of code put it on the beginning of a line before the block:
var copies []*string
//scopelint:ignore
for _, val := range values {
copies = append(copies, &val)
}Also, you can exclude all issues in a file by:
//scopelint:ignore
package pkgYou may add a comment explaining or justifying why //scopelint:ignore is being used on the same line as the flag itself:
//scopelint:ignore // any commentscopelint can be used with gometalinter in --linter flag.
gometalinter --disable-all --linter 'scope:scopelint {path}:^(?P<path>.*?\.go):(?P<line>\d+):(?P<col>\d+):\s*(?P<message>.*)$'
scopelint returns 1 if any problems were found in the checked files. It returns 2 if there were any other failures.
- False positive for for table tests #4
- I won't fix it because scopelint supports ignore them all. => nolint
- Write tests
- License (Some codes copied from golint)