os: make IsExists also recognize syscall.ENOTEMPTY

And adds missing tests.

Fixes #14970

Change-Id: I0dba02603bc245f555498cb5dd3e0a9d87c52353
Reviewed-on: https://go-review.googlesource.com/21467Reviewed-by: Ian Lance Taylor <iant@golang.org>
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>

src/os/error_test.go

@@ -80,11 +80,13 @@ func checkErrorPredicate(predName string, pred func(error) bool, err error) stri
 	return ""
 }
 
-var isExistTests = []struct {
+type isExistTest struct {
 	err   error
 	is    bool
 	isnot bool
-}{
+}
+
+var isExistTests = []isExistTest{
 	{&os.PathError{Err: os.ErrInvalid}, false, false},
 	{&os.PathError{Err: os.ErrPermission}, false, false},
 	{&os.PathError{Err: os.ErrExist}, true, false},
@@ -109,10 +111,12 @@ func TestIsExist(t *testing.T) {
 	}
 }
 
-var isPermissionTests = []struct {
+type isPermissionTest struct {
 	err  error
 	want bool
-}{
+}
+
+var isPermissionTests = []isPermissionTest{
 	{nil, false},
 	{&os.PathError{Err: os.ErrPermission}, true},
 	{&os.SyscallError{Err: os.ErrPermission}, true},

src/os/error_unix.go

@@ -19,7 +19,7 @@ func isExist(err error) bool {
 	case *SyscallError:
 		err = pe.Err
 	}
-	return err == syscall.EEXIST || err == ErrExist
+	return err == syscall.EEXIST || err == syscall.ENOTEMPTY || err == ErrExist
 }
 
 func isNotExist(err error) bool {

src/os/error_unix_test.go

+// Copyright 2016 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.
+
+// +build darwin dragonfly freebsd linux nacl netbsd openbsd solaris
+
+package os_test
+
+import (
+	"os"
+	"syscall"
+)
+
+func init() {
+	isExistTests = append(isExistTests,
+		isExistTest{err: &os.PathError{Err: syscall.EEXIST}, is: true, isnot: false},
+		isExistTest{err: &os.PathError{Err: syscall.ENOTEMPTY}, is: true, isnot: false},
+
+		isExistTest{err: &os.LinkError{Err: syscall.EEXIST}, is: true, isnot: false},
+		isExistTest{err: &os.LinkError{Err: syscall.ENOTEMPTY}, is: true, isnot: false},
+
+		isExistTest{err: &os.SyscallError{Err: syscall.EEXIST}, is: true, isnot: false},
+		isExistTest{err: &os.SyscallError{Err: syscall.ENOTEMPTY}, is: true, isnot: false},
+	)
+	isPermissionTests = append(isPermissionTests,
+		isPermissionTest{err: &os.PathError{Err: syscall.EACCES}, want: true},
+		isPermissionTest{err: &os.PathError{Err: syscall.EPERM}, want: true},
+		isPermissionTest{err: &os.PathError{Err: syscall.EEXIST}, want: false},
+
+		isPermissionTest{err: &os.LinkError{Err: syscall.EACCES}, want: true},
+		isPermissionTest{err: &os.LinkError{Err: syscall.EPERM}, want: true},
+		isPermissionTest{err: &os.LinkError{Err: syscall.EEXIST}, want: false},
+
+		isPermissionTest{err: &os.SyscallError{Err: syscall.EACCES}, want: true},
+		isPermissionTest{err: &os.SyscallError{Err: syscall.EPERM}, want: true},
+		isPermissionTest{err: &os.SyscallError{Err: syscall.EEXIST}, want: false},
+	)
+
+}

src/os/error_windows_test.go

+// Copyright 2016 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.
+
+// +build windows
+
+package os_test
+
+import (
+	"os"
+	"syscall"
+)
+
+func init() {
+	const _ERROR_BAD_NETPATH = syscall.Errno(53)
+
+	isExistTests = append(isExistTests,
+		isExistTest{err: &os.PathError{Err: syscall.ERROR_FILE_NOT_FOUND}, is: false, isnot: true},
+		isExistTest{err: &os.LinkError{Err: syscall.ERROR_FILE_NOT_FOUND}, is: false, isnot: true},
+		isExistTest{err: &os.SyscallError{Err: syscall.ERROR_FILE_NOT_FOUND}, is: false, isnot: true},
+
+		isExistTest{err: &os.PathError{Err: _ERROR_BAD_NETPATH}, is: false, isnot: true},
+		isExistTest{err: &os.LinkError{Err: _ERROR_BAD_NETPATH}, is: false, isnot: true},
+		isExistTest{err: &os.SyscallError{Err: _ERROR_BAD_NETPATH}, is: false, isnot: true},
+
+		isExistTest{err: &os.PathError{Err: syscall.ERROR_PATH_NOT_FOUND}, is: false, isnot: true},
+		isExistTest{err: &os.LinkError{Err: syscall.ERROR_PATH_NOT_FOUND}, is: false, isnot: true},
+		isExistTest{err: &os.SyscallError{Err: syscall.ERROR_PATH_NOT_FOUND}, is: false, isnot: true},
+	)
+	isPermissionTests = append(isPermissionTests,
+		isPermissionTest{err: &os.PathError{Err: syscall.ERROR_ACCESS_DENIED}, want: true},
+		isPermissionTest{err: &os.LinkError{Err: syscall.ERROR_ACCESS_DENIED}, want: true},
+		isPermissionTest{err: &os.SyscallError{Err: syscall.ERROR_ACCESS_DENIED}, want: true},
+	)
+}