Wait for ninja proto processing to finish when exiting

Wait for the ninja proto processing goroutine to notice the fifo
has closed and exit before continuing.

Test: m nothing
Change-Id: I8cf5f3b8bf6a91496c6d2bbbd3e811eb7f0c9d21

ui/status/ninja_test.go

@@ -0,0 +1,45 @@
+// Copyright 2019 Google Inc. All rights reserved.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package status
+
+import (
+	"io/ioutil"
+	"os"
+	"path/filepath"
+	"testing"
+	"time"
+
+	"android/soong/ui/logger"
+)
+
+// Tests that closing the ninja reader when nothing has opened the other end of the fifo is fast.
+func TestNinjaReader_Close(t *testing.T) {
+	tempDir, err := ioutil.TempDir("", "ninja_test")
+	if err != nil {
+		t.Fatal(err)
+	}
+	defer os.RemoveAll(tempDir)
+
+	stat := &Status{}
+	nr := NewNinjaReader(logger.New(ioutil.Discard), stat.StartTool(), filepath.Join(tempDir, "fifo"))
+
+	start := time.Now()
+
+	nr.Close()
+
+	if g, w := time.Since(start), NINJA_READER_CLOSE_TIMEOUT; g >= w {
+		t.Errorf("nr.Close timed out, %s > %s", g, w)
+	}
+}