mirror of
https://github.com/golang/go
synced 2024-10-01 18:28:32 -06:00
95c9b7bad1
Over time, a number of modules were added that used Warn instead of Bad to report problems with the code, but the documentation states that if there is a problem, the exit code must be 1, not 0. Warn does not set the exit code and should be used only for internal errors and messages triggered by the -v flag. There's nothing substantive here except calling the other function in a few places. Fixes golang/go#7017. LGTM=crawshaw R=golang-codereviews, crawshaw CC=golang-codereviews https://golang.org/cl/71860044
66 lines
1.5 KiB
Go
66 lines
1.5 KiB
Go
// Copyright 2012 The Go Authors. All rights reserved.
|
|
// Use of this source code is governed by a BSD-style
|
|
// license that can be found in the LICENSE file.
|
|
|
|
/*
|
|
This file contains the code to check range loop variables bound inside function
|
|
literals that are deferred or launched in new goroutines. We only check
|
|
instances where the defer or go statement is the last statement in the loop
|
|
body, as otherwise we would need whole program analysis.
|
|
|
|
For example:
|
|
|
|
for i, v := range s {
|
|
go func() {
|
|
println(i, v) // not what you might expect
|
|
}()
|
|
}
|
|
|
|
See: http://golang.org/doc/go_faq.html#closures_and_goroutines
|
|
*/
|
|
|
|
package main
|
|
|
|
import "go/ast"
|
|
|
|
// checkRangeLoop walks the body of the provided range statement, checking if
|
|
// its index or value variables are used unsafely inside goroutines or deferred
|
|
// function literals.
|
|
func checkRangeLoop(f *File, n *ast.RangeStmt) {
|
|
if !vet("rangeloops") {
|
|
return
|
|
}
|
|
key, _ := n.Key.(*ast.Ident)
|
|
val, _ := n.Value.(*ast.Ident)
|
|
if key == nil && val == nil {
|
|
return
|
|
}
|
|
sl := n.Body.List
|
|
if len(sl) == 0 {
|
|
return
|
|
}
|
|
var last *ast.CallExpr
|
|
switch s := sl[len(sl)-1].(type) {
|
|
case *ast.GoStmt:
|
|
last = s.Call
|
|
case *ast.DeferStmt:
|
|
last = s.Call
|
|
default:
|
|
return
|
|
}
|
|
lit, ok := last.Fun.(*ast.FuncLit)
|
|
if !ok {
|
|
return
|
|
}
|
|
ast.Inspect(lit.Body, func(n ast.Node) bool {
|
|
id, ok := n.(*ast.Ident)
|
|
if !ok || id.Obj == nil {
|
|
return true
|
|
}
|
|
if key != nil && id.Obj == key.Obj || val != nil && id.Obj == val.Obj {
|
|
f.Bad(id.Pos(), "range variable", id.Name, "enclosed by function")
|
|
}
|
|
return true
|
|
})
|
|
}
|