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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-28 13:16:40 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-28 13:16:40 +0000
commit47ab3d4a42e9ab51c465c4322d2ec233f6324e6b (patch)
treea61a0ffd83f4a3def4b36e5c8e99630c559aa723 /test/closedchan.go
parentInitial commit. (diff)
downloadgolang-1.18-47ab3d4a42e9ab51c465c4322d2ec233f6324e6b.tar.xz
golang-1.18-47ab3d4a42e9ab51c465c4322d2ec233f6324e6b.zip
Adding upstream version 1.18.10.upstream/1.18.10upstream
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'test/closedchan.go')
-rw-r--r--test/closedchan.go359
1 files changed, 359 insertions, 0 deletions
diff --git a/test/closedchan.go b/test/closedchan.go
new file mode 100644
index 0000000..043a92d
--- /dev/null
+++ b/test/closedchan.go
@@ -0,0 +1,359 @@
+// run
+
+// Copyright 2009 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.
+
+// Test close(c), receive of closed channel.
+//
+// TODO(rsc): Doesn't check behavior of close(c) when there
+// are blocked senders/receivers.
+
+package main
+
+import "os"
+
+var failed bool
+
+type Chan interface {
+ Send(int)
+ Nbsend(int) bool
+ Recv() (int)
+ Nbrecv() (int, bool)
+ Recv2() (int, bool)
+ Nbrecv2() (int, bool, bool)
+ Close()
+ Impl() string
+}
+
+// direct channel operations when possible
+type XChan chan int
+
+func (c XChan) Send(x int) {
+ c <- x
+}
+
+func (c XChan) Nbsend(x int) bool {
+ select {
+ case c <- x:
+ return true
+ default:
+ return false
+ }
+ panic("nbsend")
+}
+
+func (c XChan) Recv() int {
+ return <-c
+}
+
+func (c XChan) Nbrecv() (int, bool) {
+ select {
+ case x := <-c:
+ return x, true
+ default:
+ return 0, false
+ }
+ panic("nbrecv")
+}
+
+func (c XChan) Recv2() (int, bool) {
+ x, ok := <-c
+ return x, ok
+}
+
+func (c XChan) Nbrecv2() (int, bool, bool) {
+ select {
+ case x, ok := <-c:
+ return x, ok, true
+ default:
+ return 0, false, false
+ }
+ panic("nbrecv2")
+}
+
+func (c XChan) Close() {
+ close(c)
+}
+
+func (c XChan) Impl() string {
+ return "(<- operator)"
+}
+
+// indirect operations via select
+type SChan chan int
+
+func (c SChan) Send(x int) {
+ select {
+ case c <- x:
+ }
+}
+
+func (c SChan) Nbsend(x int) bool {
+ select {
+ default:
+ return false
+ case c <- x:
+ return true
+ }
+ panic("nbsend")
+}
+
+func (c SChan) Recv() int {
+ select {
+ case x := <-c:
+ return x
+ }
+ panic("recv")
+}
+
+func (c SChan) Nbrecv() (int, bool) {
+ select {
+ default:
+ return 0, false
+ case x := <-c:
+ return x, true
+ }
+ panic("nbrecv")
+}
+
+func (c SChan) Recv2() (int, bool) {
+ select {
+ case x, ok := <-c:
+ return x, ok
+ }
+ panic("recv")
+}
+
+func (c SChan) Nbrecv2() (int, bool, bool) {
+ select {
+ default:
+ return 0, false, false
+ case x, ok := <-c:
+ return x, ok, true
+ }
+ panic("nbrecv")
+}
+
+func (c SChan) Close() {
+ close(c)
+}
+
+func (c SChan) Impl() string {
+ return "(select)"
+}
+
+// indirect operations via larger selects
+var dummy = make(chan bool)
+
+type SSChan chan int
+
+func (c SSChan) Send(x int) {
+ select {
+ case c <- x:
+ case <-dummy:
+ }
+}
+
+func (c SSChan) Nbsend(x int) bool {
+ select {
+ default:
+ return false
+ case <-dummy:
+ case c <- x:
+ return true
+ }
+ panic("nbsend")
+}
+
+func (c SSChan) Recv() int {
+ select {
+ case <-dummy:
+ case x := <-c:
+ return x
+ }
+ panic("recv")
+}
+
+func (c SSChan) Nbrecv() (int, bool) {
+ select {
+ case <-dummy:
+ default:
+ return 0, false
+ case x := <-c:
+ return x, true
+ }
+ panic("nbrecv")
+}
+
+func (c SSChan) Recv2() (int, bool) {
+ select {
+ case <-dummy:
+ case x, ok := <-c:
+ return x, ok
+ }
+ panic("recv")
+}
+
+func (c SSChan) Nbrecv2() (int, bool, bool) {
+ select {
+ case <-dummy:
+ default:
+ return 0, false, false
+ case x, ok := <-c:
+ return x, ok, true
+ }
+ panic("nbrecv")
+}
+
+func (c SSChan) Close() {
+ close(c)
+}
+
+func (c SSChan) Impl() string {
+ return "(select)"
+}
+
+
+func shouldPanic(f func()) {
+ defer func() {
+ if recover() == nil {
+ panic("did not panic")
+ }
+ }()
+ f()
+}
+
+func test1(c Chan) {
+ for i := 0; i < 3; i++ {
+ // recv a close signal (a zero value)
+ if x := c.Recv(); x != 0 {
+ println("test1: recv on closed:", x, c.Impl())
+ failed = true
+ }
+ if x, ok := c.Recv2(); x != 0 || ok {
+ println("test1: recv2 on closed:", x, ok, c.Impl())
+ failed = true
+ }
+
+ // should work with select: received a value without blocking, so selected == true.
+ x, selected := c.Nbrecv()
+ if x != 0 || !selected {
+ println("test1: recv on closed nb:", x, selected, c.Impl())
+ failed = true
+ }
+ x, ok, selected := c.Nbrecv2()
+ if x != 0 || ok || !selected {
+ println("test1: recv2 on closed nb:", x, ok, selected, c.Impl())
+ failed = true
+ }
+ }
+
+ // send should work with ,ok too: sent a value without blocking, so ok == true.
+ shouldPanic(func() { c.Nbsend(1) })
+
+ // the value should have been discarded.
+ if x := c.Recv(); x != 0 {
+ println("test1: recv on closed got non-zero after send on closed:", x, c.Impl())
+ failed = true
+ }
+
+ // similarly Send.
+ shouldPanic(func() { c.Send(2) })
+ if x := c.Recv(); x != 0 {
+ println("test1: recv on closed got non-zero after send on closed:", x, c.Impl())
+ failed = true
+ }
+}
+
+func testasync1(c Chan) {
+ // should be able to get the last value via Recv
+ if x := c.Recv(); x != 1 {
+ println("testasync1: Recv did not get 1:", x, c.Impl())
+ failed = true
+ }
+
+ test1(c)
+}
+
+func testasync2(c Chan) {
+ // should be able to get the last value via Recv2
+ if x, ok := c.Recv2(); x != 1 || !ok {
+ println("testasync1: Recv did not get 1, true:", x, ok, c.Impl())
+ failed = true
+ }
+
+ test1(c)
+}
+
+func testasync3(c Chan) {
+ // should be able to get the last value via Nbrecv
+ if x, selected := c.Nbrecv(); x != 1 || !selected {
+ println("testasync2: Nbrecv did not get 1, true:", x, selected, c.Impl())
+ failed = true
+ }
+
+ test1(c)
+}
+
+func testasync4(c Chan) {
+ // should be able to get the last value via Nbrecv2
+ if x, ok, selected := c.Nbrecv2(); x != 1 || !ok || !selected {
+ println("testasync2: Nbrecv did not get 1, true, true:", x, ok, selected, c.Impl())
+ failed = true
+ }
+ test1(c)
+}
+
+func closedsync() chan int {
+ c := make(chan int)
+ close(c)
+ return c
+}
+
+func closedasync() chan int {
+ c := make(chan int, 2)
+ c <- 1
+ close(c)
+ return c
+}
+
+var mks = []func(chan int) Chan {
+ func(c chan int) Chan { return XChan(c) },
+ func(c chan int) Chan { return SChan(c) },
+ func(c chan int) Chan { return SSChan(c) },
+}
+
+var testcloseds = []func(Chan) {
+ testasync1,
+ testasync2,
+ testasync3,
+ testasync4,
+}
+
+func main() {
+ for _, mk := range mks {
+ test1(mk(closedsync()))
+ }
+
+ for _, testclosed := range testcloseds {
+ for _, mk := range mks {
+ testclosed(mk(closedasync()))
+ }
+ }
+
+ var ch chan int
+ shouldPanic(func() {
+ close(ch)
+ })
+
+ ch = make(chan int)
+ close(ch)
+ shouldPanic(func() {
+ close(ch)
+ })
+
+ if failed {
+ os.Exit(1)
+ }
+}