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// 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 tests for the loopclosure checker.
package testdata
import "golang.org/x/sync/errgroup"
func _() {
var s []int
for i, v := range s {
go func() {
println(i) // want "loop variable i captured by func literal"
println(v) // want "loop variable v captured by func literal"
}()
}
for i, v := range s {
defer func() {
println(i) // want "loop variable i captured by func literal"
println(v) // want "loop variable v captured by func literal"
}()
}
for i := range s {
go func() {
println(i) // want "loop variable i captured by func literal"
}()
}
for _, v := range s {
go func() {
println(v) // want "loop variable v captured by func literal"
}()
}
for i, v := range s {
go func() {
println(i, v)
}()
println("unfortunately, we don't catch the error above because of this statement")
}
for i, v := range s {
go func(i, v int) {
println(i, v)
}(i, v)
}
for i, v := range s {
i, v := i, v
go func() {
println(i, v)
}()
}
// If the key of the range statement is not an identifier
// the code should not panic (it used to).
var x [2]int
var f int
for x[0], f = range s {
go func() {
_ = f // want "loop variable f captured by func literal"
}()
}
type T struct {
v int
}
for _, v := range s {
go func() {
_ = T{v: 1}
_ = map[int]int{v: 1} // want "loop variable v captured by func literal"
}()
}
// ordinary for-loops
for i := 0; i < 10; i++ {
go func() {
print(i) // want "loop variable i captured by func literal"
}()
}
for i, j := 0, 1; i < 100; i, j = j, i+j {
go func() {
print(j) // want "loop variable j captured by func literal"
}()
}
type cons struct {
car int
cdr *cons
}
var head *cons
for p := head; p != nil; p = p.cdr {
go func() {
print(p.car) // want "loop variable p captured by func literal"
}()
}
}
// Group is used to test that loopclosure does not match on any type named "Group".
// The checker only matches on methods "(*...errgroup.Group).Go".
type Group struct{};
func (g *Group) Go(func() error) {}
func _() {
var s []int
// errgroup.Group.Go() invokes Go routines
g := new(errgroup.Group)
for i, v := range s {
g.Go(func() error {
print(i) // want "loop variable i captured by func literal"
print(v) // want "loop variable v captured by func literal"
return nil
})
}
// Do not match other Group.Go cases
g1 := new(Group)
for i, v := range s {
g1.Go(func() error {
print(i)
print(v)
return nil
})
}
}
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