Flush() output from noms diff to ensure results are printed.

cmd/noms/noms_diff.go

@@ -52,8 +52,6 @@ func runDiff(args []string) int {
 	defer db2.Close()
 
 	waitChan := outputpager.PageOutput()
-	w := bufio.NewWriter(os.Stdout)
-
 	if waitChan != nil {
 		go func() {
 			<-waitChan
@@ -61,6 +59,8 @@ func runDiff(args []string) int {
 		}()
 	}
 
+	w := bufio.NewWriter(os.Stdout)
 	diff.Diff(w, value1, value2)
+	w.Flush()
 	return 0
 }

cmd/noms/noms_diff_test.go

@@ -0,0 +1,42 @@
+// Copyright 2016 Attic Labs, Inc. All rights reserved.
+// Licensed under the Apache License, version 2.0:
+// http://www.apache.org/licenses/LICENSE-2.0
+
+package main
+
+import (
+	"testing"
+
+	"github.com/attic-labs/noms/go/spec"
+	"github.com/attic-labs/noms/go/util/clienttest"
+	"github.com/attic-labs/testify/suite"
+)
+
+type nomsDiffTestSuite struct {
+	clienttest.ClientTestSuite
+}
+
+func TestNomsDiff(t *testing.T) {
+	suite.Run(t, &nomsDiffTestSuite{})
+}
+
+func (s *nomsDiffTestSuite) TestNomsDiffOutputNotTruncated() {
+	datasetName := "diffTest"
+	str := spec.CreateValueSpecString("ldb", s.LdbDir, datasetName)
+	ds, err := spec.GetDataset(str)
+	s.NoError(err)
+
+	ds, err = addCommit(ds, "first commit")
+	s.NoError(err)
+	r1 := spec.CreateValueSpecString("ldb", s.LdbDir, "#"+ds.HeadRef().TargetHash().String())
+
+	ds, err = addCommit(ds, "second commit")
+	s.NoError(err)
+	r2 := spec.CreateValueSpecString("ldb", s.LdbDir, "#"+ds.HeadRef().TargetHash().String())
+
+	ds.Database().Close()
+	out, _ := s.Run(main, []string{"diff", r1, r2})
+	if s.True(len(out) > 3) {
+		s.Equal(out[len(out)-2:], "}\n")
+	}
+}