net: deflake timeout, deadline tests

This change deflakes timeout, deadline tests, especially fixes socket
and goroutine leaks. Also adds a few missing tests that use features
introduced after go1 release.

Change-Id: Ibf73a4859f8d4a0ee494ca2fd180cbce72a7a2c7
Reviewed-on: https://go-review.googlesource.com/9464Reviewed-by: Ian Lance Taylor <iant@golang.org>

src/net/error_plan9_test.go

@@ -6,7 +6,10 @@ package net
 
 import "syscall"
 
-var errOpNotSupported = syscall.EPLAN9
+var (
+	errTimedout       = syscall.ETIMEDOUT
+	errOpNotSupported = syscall.EPLAN9
+)
 
 func isPlatformError(err error) bool {
 	_, ok := err.(syscall.ErrorString)

src/net/error_posix_test.go

@@ -8,7 +8,10 @@ package net
 
 import "syscall"
 
-var errOpNotSupported = syscall.EOPNOTSUPP
+var (
+	errTimedout       = syscall.ETIMEDOUT
+	errOpNotSupported = syscall.EOPNOTSUPP
+)
 
 func isPlatformError(err error) bool {
 	_, ok := err.(syscall.Errno)

src/net/error_test.go

@@ -15,16 +15,6 @@ import (
 	"time"
 )
 
-func isTimeoutError(err error) bool {
-	nerr, ok := err.(Error)
-	return ok && nerr.Timeout()
-}
-
-func isTemporaryError(err error) bool {
-	nerr, ok := err.(Error)
-	return ok && nerr.Temporary()
-}
-
 func (e *OpError) isValid() error {
 	if e.Op == "" {
 		return fmt.Errorf("OpError.Op is empty: %v", e)
@@ -467,7 +457,7 @@ func TestAcceptError(t *testing.T) {
 				if c != nil {
 					t.Errorf("Accept returned non-nil interface %T(%v) with err != nil", c, c)
 				}
-				if !isTimeoutError(err) && !isTemporaryError(err) {
+				if nerr, ok := err.(Error); !ok || (!nerr.Timeout() && !nerr.Temporary()) {
 					return
 				}
 				continue
@@ -521,6 +511,10 @@ second:
 		nestedErr = err.Err
 		goto third
 	}
+	switch nestedErr {
+	case errClosing:
+		return nil
+	}
 	return fmt.Errorf("unexpected type on 2nd nested level: %T", nestedErr)
 
 third:

src/net/mockserver_test.go

@@ -9,6 +9,7 @@ import (
 	"io/ioutil"
 	"os"
 	"sync"
+	"testing"
 	"time"
 )
 
@@ -250,6 +251,54 @@ func transceiver(c Conn, wb []byte, ch chan<- error) {
 	}
 }
 
+func timeoutReceiver(c Conn, d, min, max time.Duration, ch chan<- error) {
+	var err error
+	defer func() { ch <- err }()
+
+	t0 := time.Now()
+	if err = c.SetReadDeadline(time.Now().Add(d)); err != nil {
+		return
+	}
+	b := make([]byte, 256)
+	var n int
+	n, err = c.Read(b)
+	t1 := time.Now()
+	if n != 0 || err == nil || !err.(Error).Timeout() {
+		err = fmt.Errorf("Read did not return (0, timeout): (%d, %v)", n, err)
+		return
+	}
+	if dt := t1.Sub(t0); min > dt || dt > max && !testing.Short() {
+		err = fmt.Errorf("Read took %s; expected %s", dt, d)
+		return
+	}
+}
+
+func timeoutTransmitter(c Conn, d, min, max time.Duration, ch chan<- error) {
+	var err error
+	defer func() { ch <- err }()
+
+	t0 := time.Now()
+	if err = c.SetWriteDeadline(time.Now().Add(d)); err != nil {
+		return
+	}
+	var n int
+	for {
+		n, err = c.Write([]byte("TIMEOUT TRANSMITTER"))
+		if err != nil {
+			break
+		}
+	}
+	t1 := time.Now()
+	if err == nil || !err.(Error).Timeout() {
+		err = fmt.Errorf("Write did not return (any, timeout): (%d, %v)", n, err)
+		return
+	}
+	if dt := t1.Sub(t0); min > dt || dt > max && !testing.Short() {
+		err = fmt.Errorf("Write took %s; expected %s", dt, d)
+		return
+	}
+}
+
 func newLocalPacketListener(network string) (PacketConn, error) {
 	switch network {
 	case "udp", "udp4", "udp6":
@@ -380,3 +429,25 @@ func packetTransceiver(c PacketConn, wb []byte, dst Addr, ch chan<- error) {
 		ch <- fmt.Errorf("read %d; want %d", n, len(wb))
 	}
 }
+
+func timeoutPacketReceiver(c PacketConn, d, min, max time.Duration, ch chan<- error) {
+	var err error
+	defer func() { ch <- err }()
+
+	t0 := time.Now()
+	if err = c.SetReadDeadline(time.Now().Add(d)); err != nil {
+		return
+	}
+	b := make([]byte, 256)
+	var n int
+	n, _, err = c.ReadFrom(b)
+	t1 := time.Now()
+	if n != 0 || err == nil || !err.(Error).Timeout() {
+		err = fmt.Errorf("ReadFrom did not return (0, timeout): (%d, %v)", n, err)
+		return
+	}
+	if dt := t1.Sub(t0); min > dt || dt > max && !testing.Short() {
+		err = fmt.Errorf("ReadFrom took %s; expected %s", dt, d)
+		return
+	}
+}

src/net/udp_test.go

@@ -95,7 +95,8 @@ func TestReadFromUDP(t *testing.T) {
 	_, _, err = c.ReadFromUDP(b)
 	if err == nil {
 		t.Fatal("ReadFromUDP should fail")
-	} else if !isTimeoutError(err) {
+	}
+	if nerr, ok := err.(Error); !ok || !nerr.Timeout() {
 		t.Fatal(err)
 	}
 }