Merge pull request #1516 from rht/progressbar

Clear progress bar on `ipfs cat` exit

core/commands/add.go

@@ -4,7 +4,6 @@ import (
 	"fmt"
 	"io"
 	"path"
-	"strings"
 
 	"github.com/ipfs/go-ipfs/Godeps/_workspace/src/github.com/cheggaaa/pb"
 
@@ -208,7 +207,7 @@ remains to be implemented.
 			if len(output.Hash) > 0 {
 				if showProgressBar {
 					// clear progress bar line before we print "added x" output
-					fmt.Fprintf(res.Stderr(), "\r%s\r", strings.Repeat(" ", terminalWidth))
+					fmt.Fprintf(res.Stderr(), "\033[2K\r")
 				}
 				if quiet {
 					fmt.Fprintf(res.Stdout(), "%s\n", output.Hash)

core/commands/cat.go

 package commands
 
 import (
+	"fmt"
 	"io"
 
 	cmds "github.com/ipfs/go-ipfs/commands"
@@ -14,6 +15,11 @@ import (
 
 const progressBarMinSize = 1024 * 1024 * 8 // show progress bar for outputs > 8MiB
 
+type clearlineReader struct {
+	io.Reader
+	out io.Writer
+}
+
 var CatCmd = &cmds.Command{
 	Helptext: cmds.HelpText{
 		Tagline: "Show IPFS object data",
@@ -54,7 +60,7 @@ it contains.
 		bar.Start()
 
 		reader := bar.NewProxyReader(res.Output().(io.Reader))
-		res.SetOutput(reader)
+		res.SetOutput(&clearlineReader{reader, res.Stderr()})
 	},
 }
 
@@ -76,3 +82,11 @@ func cat(ctx context.Context, node *core.IpfsNode, paths []string) ([]io.Reader,
 	}
 	return readers, length, nil
 }
+
+func (r *clearlineReader) Read(p []byte) (n int, err error) {
+	n, err = r.Reader.Read(p)
+	if err == io.EOF {
+		fmt.Fprintf(r.out, "\033[2K\r") // clear progress bar line on EOF
+	}
+	return
+}