Restrict size to 2 fractional digits for `docker images`

This fix tries to address the issue raised in 26300. Previously
`docker images` will use `HumanSize()` to display the size which
has a fixed precision of 4 (thus 3 fractional digits). This
could be problematic in certain languages (e.g. , German, see
26300) as `.` may be interpreted as thousands-separator in number.

This fix use `CustomSize()` instead and limit the precision to 3
(thus 2 fractional digits).

This fix has been tested manually.

This fix fixes 26300.

Signed-off-by: Yong Tang <yong.tang.github@outlook.com>

cli/command/container/stats_helpers.go

@@ -194,8 +194,8 @@ func (s *containerStats) Display(w io.Writer) error {
 		s.CPUPercentage,
 		units.BytesSize(s.Memory), units.BytesSize(s.MemoryLimit),
 		s.MemoryPercentage,
-		units.HumanSize(s.NetworkRx), units.HumanSize(s.NetworkTx),
-		units.HumanSize(s.BlockRead), units.HumanSize(s.BlockWrite),
+		units.HumanSizeWithPrecision(s.NetworkRx, 3), units.HumanSizeWithPrecision(s.NetworkTx, 3),
+		units.HumanSizeWithPrecision(s.BlockRead, 3), units.HumanSizeWithPrecision(s.BlockWrite, 3),
 		s.PidsCurrent)
 	return nil
 }

cli/command/container/stats_unit_test.go

@@ -25,7 +25,7 @@ func TestDisplay(t *testing.T) {
 		t.Fatalf("c.Display() gave error: %s", err)
 	}
 	got := b.String()
-	want := "app\t30.00%\t100 MiB / 2 GiB\t4.88%\t104.9 MB / 838.9 MB\t104.9 MB / 838.9 MB\t1\n"
+	want := "app\t30.00%\t100 MiB / 2 GiB\t4.88%\t105 MB / 839 MB\t105 MB / 839 MB\t1\n"
 	if got != want {
 		t.Fatalf("c.Display() = %q, want %q", got, want)
 	}

cli/command/formatter/container.go

@@ -152,8 +152,8 @@ func (c *containerContext) Status() string {
 
 func (c *containerContext) Size() string {
 	c.addHeader(sizeHeader)
-	srw := units.HumanSize(float64(c.c.SizeRw))
-	sv := units.HumanSize(float64(c.c.SizeRootFs))
+	srw := units.HumanSizeWithPrecision(float64(c.c.SizeRw), 3)
+	sv := units.HumanSizeWithPrecision(float64(c.c.SizeRootFs), 3)
 
 	sf := srw
 	if c.c.SizeRootFs > 0 {

cli/command/formatter/image.go

@@ -225,5 +225,5 @@ func (c *imageContext) CreatedAt() string {
 
 func (c *imageContext) Size() string {
 	c.addHeader(sizeHeader)
-	return units.HumanSize(float64(c.i.Size))
+	return units.HumanSizeWithPrecision(float64(c.i.Size), 3)
 }

cli/command/image/history.go

@@ -86,7 +86,7 @@ func runHistory(dockerCli *command.DockerCli, opts historyOptions) error {
 
 		if opts.human {
 			created = units.HumanDuration(time.Now().UTC().Sub(time.Unix(entry.Created, 0))) + " ago"
-			size = units.HumanSize(float64(entry.Size))
+			size = units.HumanSizeWithPrecision(float64(entry.Size), 3)
 		} else {
 			created = time.Unix(entry.Created, 0).Format(time.RFC3339)
 			size = strconv.FormatInt(entry.Size, 10)