Butler stream servers can generate client address.

logdog/client/butler/streamserver/namedPipe_posix_test.go

Index: logdog/client/butler/streamserver/namedPipe_posix_test.go
diff --git a/logdog/client/butler/streamserver/namedPipe_posix_test.go b/logdog/client/butler/streamserver/namedPipe_posix_test.go
new file mode 100644
index 0000000000000000000000000000000000000000..a8c2a4d2c89f87d4142638315f7f5bf131e05f17
--- /dev/null
+++ b/logdog/client/butler/streamserver/namedPipe_posix_test.go
@@ -0,0 +1,68 @@
+// Copyright 2017 The LUCI Authors. All rights reserved.
+// Use of this source code is governed under the Apache License, Version 2.0
+// that can be found in the LICENSE file.
+
+// +build darwin dragonfly freebsd linux netbsd openbsd
+
+package streamserver
+
+import (
+	"io/ioutil"
+	"os"
+	"path/filepath"
+	"strings"
+	"testing"
+
+	"github.com/luci/luci-go/logdog/client/butlerlib/streamclient"
+
+	"golang.org/x/net/context"
+
+	. "github.com/luci/luci-go/common/testing/assertions"
+	. "github.com/smartystreets/goconvey/convey"
+)
+
+func withTempDir(t *testing.T, fn func(string)) func() {
+	return func() {
+		tdir, err := ioutil.TempDir("", "butler_test")
+		if err != nil {
+			t.Fatalf("failed to create temporary directory: %s", err)
+		}
+		defer func() {
+			if err := os.RemoveAll(tdir); err != nil {
+				t.Errorf("failed to clean up temporary directory [%s]: %s", tdir, err)
+			}
+		}()
+		fn(tdir)
+	}
+}
+
+func TestUNIXDomainSocketServer(t *testing.T) {
+	t.Parallel()
+
+	Convey(`A UNIX domain socket server`, t, func() {
+		ctx := context.Background()
+
+		Convey(`Will refuse to create if there is an empty path.`, func() {
+			_, err := NewUNIXDomainSocketServer(ctx, "")
+			So(err, ShouldErrLike, "cannot have empty path")
+		})
+
+		Convey(`Will refuse to create if longer than maximum length.`, func() {
+			_, err := NewUNIXDomainSocketServer(ctx, strings.Repeat("A", maxPOSIXNamedSocketLength+1))
+			So(err, ShouldErrLike, "path exceeds maximum length")
+		})
+
+		Convey(`When created and listening.`, withTempDir(t, func(tdir string) {
+			svr, err := NewUNIXDomainSocketServer(ctx, filepath.Join(tdir, "butler.sock"))
+			So(err, ShouldBeNil)
+
+			So(svr.Listen(), ShouldBeNil)
+			defer svr.Close()
+
+			client, err := streamclient.New(svr.Address())
+			So(err, ShouldBeNil)
+
+			testClientServer(t, svr, client)
+		}))
+	})
+}