image/tree: Hide Content size column without containerd store

With graph drivers, all content sizes are zero because the compressed
content isn't stored.
This makes the whole column useless and wasting the terminal space.

Hide the whole column if all its values would be zero.

Signed-off-by: Paweł Gronowski <pawel.gronowski@docker.com>

Author: vvoland

cli/command/image/tree.go

@@ -245,6 +245,21 @@ func printImageTree(dockerCLI command.Cli, view treeView) error {
 			DetailsValue: func(d *imageDetails) string {
 				return d.ContentSize
 			},
+			// Hide if all content sizes are 0
+			Hide: func() bool {
+				zero := units.HumanSize(0.0)
+				for _, img := range view.images {
+					if img.Details.ContentSize != zero {
+						return false
+					}
+					for _, sub := range img.Children {
+						if sub.Details.ContentSize != zero {
+							return false
+						}
+					}
+				}
+				return true
+			},
 		},
 		{
 			Title: "Extra",
@@ -308,7 +323,15 @@ func printImageTree(dockerCLI command.Cli, view treeView) error {
 // adjustColumns adjusts the width of the first column to maximize the space
 // available for image names and removes any columns that would be too narrow
 // to display their content.
+// Also removes any columns that should not be displayed.
 func adjustColumns(width uint, columns []imgColumn, images []topImage) []imgColumn {
+	for idx := len(columns) - 1; idx >= 0; idx-- {
+		h := columns[idx]
+		if h.Hide != nil && h.Hide() {
+			columns = append(columns[:idx], columns[idx+1:]...)
+		}
+	}
+
 	nameWidth := int(width)
 	for idx, h := range columns {
 		if h.Width == 0 {
@@ -429,6 +452,7 @@ type imgColumn struct {
 
 	DetailsValue func(*imageDetails) string
 	Color        *aec.ANSI
+	Hide         func() bool
 }
 
 func (h imgColumn) Print(clr aec.ANSI, s string) string {