add noms show --raw (#2991)

add noms show --raw

cmd/noms/noms_show.go

@@ -5,7 +5,9 @@
 package main
 
 import (
+	"bytes"
 	"fmt"
+	"io"
 	"os"
 
 	"github.com/attic-labs/noms/cmd/util"
@@ -19,17 +21,20 @@ import (
 
 var nomsShow = &util.Command{
 	Run:       runShow,
-	UsageLine: "show <object>",
+	UsageLine: "show [flags] <object>",
 	Short:     "Shows a serialization of a Noms object",
 	Long:      "See Spelling Objects at https://github.com/attic-labs/noms/blob/master/doc/spelling.md for details on the object argument.",
 	Flags:     setupShowFlags,
 	Nargs:     1,
 }
 
+var showRaw = false
+
 func setupShowFlags() *flag.FlagSet {
 	showFlagSet := flag.NewFlagSet("show", flag.ExitOnError)
 	outputpager.RegisterOutputpagerFlags(showFlagSet)
 	verbose.RegisterVerboseFlags(showFlagSet)
+	showFlagSet.BoolVar(&showRaw, "raw", false, "If true, dumps the raw binary version of the data")
 	return showFlagSet
 }
 
@@ -44,6 +49,14 @@ func runShow(args []string) int {
 		return 0
 	}
 
+	if showRaw {
+		ch := types.EncodeValue(value, database)
+		buf := bytes.NewBuffer(ch.Data())
+		_, err = io.Copy(os.Stdout, buf)
+		d.CheckError(err)
+		return 0
+	}
+
 	pgr := outputpager.Start()
 	defer pgr.Stop()
 

cmd/noms/noms_show_test.go

@@ -5,8 +5,10 @@
 package main
 
 import (
+	"fmt"
 	"testing"
 
+	"github.com/attic-labs/noms/go/chunks"
 	"github.com/attic-labs/noms/go/spec"
 	"github.com/attic-labs/noms/go/types"
 	"github.com/attic-labs/noms/go/util/clienttest"
@@ -69,3 +71,51 @@ func (s *nomsShowTestSuite) TestNomsShow() {
 	res, _ = s.MustRun(main, []string{"show", str})
 	test.EqualsIgnoreHashes(s.T(), res5, res)
 }
+
+func (s *nomsShowTestSuite) TestNomsShowNotFound() {
+	str := spec.CreateValueSpecString("ldb", s.LdbDir, "not-there")
+	stdout, stderr, err := s.Run(main, []string{"show", str})
+	s.Equal("", stdout)
+	s.Equal(fmt.Sprintf("Object not found: %s\n", str), stderr)
+	s.Nil(err)
+}
+
+func (s *nomsShowTestSuite) TestNomsShowRaw() {
+	datasetName := "showRaw"
+	str := spec.CreateValueSpecString("ldb", s.LdbDir, datasetName)
+	sp, err := spec.ForDataset(str)
+	s.NoError(err)
+	defer sp.Close()
+
+	db := sp.GetDatabase()
+
+	// Put a value into the db, get its raw serialization, then deserialize it and ensure it comes
+	// out to same thing.
+	test := func(in types.Value) {
+		r1 := db.WriteValue(in)
+		res, _ := s.MustRun(main, []string{"show", "--raw",
+			spec.CreateValueSpecString("ldb", s.LdbDir, "#"+r1.TargetHash().String())})
+		ch := chunks.NewChunk([]byte(res))
+		out := types.DecodeValue(ch, db)
+		s.True(out.Equals(in))
+	}
+
+	// Primitive value with no child chunks
+	test(types.String("hello"))
+
+	// Ref (one child chunk)
+	test(db.WriteValue(types.Number(42)))
+
+	// Prolly tree with multiple child chunks
+	items := make([]types.Value, 10000)
+	for i := 0; i < len(items); i++ {
+		items[i] = types.Number(i)
+	}
+	l := types.NewList(items...)
+	numChildChunks := 0
+	l.WalkRefs(func(r types.Ref) {
+		numChildChunks++
+	})
+	s.True(numChildChunks > 0)
+	test(l)
+}