remove uses of deprecated VirtualSize field

The VirtualSize field is deprecated and the upcoming API version v1.44
will no longer propagate the field. See:
moby/moby@1261fe6,

Given that in docker 1.10 and up (API v1.22), the VirtualSize and Size
fields contain the same value, and the "df" endpoint was not supported
until API v1.25, we can "safely" use Size instead; see:

- 4ae7176
- moby/moby@4352da7

Signed-off-by: Sebastiaan van Stijn <github@gone.nl>

Author: thaJeztah

cli/command/formatter/disk_usage.go

@@ -14,7 +14,7 @@ import (
 )
 
 const (
-	defaultDiskUsageImageTableFormat      = "table {{.Repository}}\t{{.Tag}}\t{{.ID}}\t{{.CreatedSince}}\t{{.VirtualSize}}\t{{.SharedSize}}\t{{.UniqueSize}}\t{{.Containers}}"
+	defaultDiskUsageImageTableFormat      = "table {{.Repository}}\t{{.Tag}}\t{{.ID}}\t{{.CreatedSince}}\t{{.Size}}\t{{.SharedSize}}\t{{.UniqueSize}}\t{{.Containers}}"
 	defaultDiskUsageContainerTableFormat  = "table {{.ID}}\t{{.Image}}\t{{.Command}}\t{{.LocalVolumes}}\t{{.Size}}\t{{.RunningFor}}\t{{.Status}}\t{{.Names}}"
 	defaultDiskUsageVolumeTableFormat     = "table {{.Name}}\t{{.Links}}\t{{.Size}}"
 	defaultDiskUsageBuildCacheTableFormat = "table {{.ID}}\t{{.CacheType}}\t{{.Size}}\t{{.CreatedSince}}\t{{.LastUsedSince}}\t{{.UsageCount}}\t{{.Shared}}"
@@ -296,10 +296,10 @@ func (c *diskUsageImagesContext) Reclaimable() string {
 
 	for _, i := range c.images {
 		if i.Containers != 0 {
-			if i.VirtualSize == -1 || i.SharedSize == -1 {
+			if i.Size == -1 || i.SharedSize == -1 {
 				continue
 			}
-			used += i.VirtualSize - i.SharedSize
+			used += i.Size - i.SharedSize
 		}
 	}
 

cli/command/formatter/image.go

@@ -205,7 +205,7 @@ func newImageContext() *imageContext {
 		"CreatedAt":    CreatedAtHeader,
 		"Size":         SizeHeader,
 		"Containers":   containersHeader,
-		"VirtualSize":  SizeHeader,
+		"VirtualSize":  SizeHeader, // Deprecated: VirtualSize is deprecated, and equivalent to Size.
 		"SharedSize":   sharedSizeHeader,
 		"UniqueSize":   uniqueSizeHeader,
 	}
@@ -260,8 +260,13 @@ func (c *imageContext) Containers() string {
 	return fmt.Sprintf("%d", c.i.Containers)
 }
 
+// VirtualSize shows the virtual size of the image and all of its parent
+// images. Starting with docker 1.10, images are self-contained, and
+// the VirtualSize is identical to Size.
+//
+// Deprecated: VirtualSize is deprecated, and equivalent to [imageContext.Size].
 func (c *imageContext) VirtualSize() string {
-	return units.HumanSize(float64(c.i.VirtualSize))
+	return units.HumanSize(float64(c.i.Size))
 }
 
 func (c *imageContext) SharedSize() string {
@@ -272,8 +277,8 @@ func (c *imageContext) SharedSize() string {
 }
 
 func (c *imageContext) UniqueSize() string {
-	if c.i.VirtualSize == -1 || c.i.SharedSize == -1 {
+	if c.i.Size == -1 || c.i.SharedSize == -1 {
 		return "N/A"
 	}
-	return units.HumanSize(float64(c.i.VirtualSize - c.i.SharedSize))
+	return units.HumanSize(float64(c.i.Size - c.i.SharedSize))
 }

cli/command/formatter/image_test.go

@@ -36,7 +36,7 @@ func TestImageContext(t *testing.T) {
 			call:     ctx.ID,
 		},
 		{
-			imageCtx: imageContext{i: types.ImageSummary{Size: 10, VirtualSize: 10}, trunc: true},
+			imageCtx: imageContext{i: types.ImageSummary{Size: 10}, trunc: true},
 			expValue: "10B",
 			call:     ctx.Size,
 		},
@@ -70,17 +70,17 @@ func TestImageContext(t *testing.T) {
 			call:     ctx.Containers,
 		},
 		{
-			imageCtx: imageContext{i: types.ImageSummary{VirtualSize: 10000}},
+			imageCtx: imageContext{i: types.ImageSummary{Size: 10000}},
 			expValue: "10kB",
-			call:     ctx.VirtualSize,
+			call:     ctx.VirtualSize, //nolint:staticcheck // ignore SA1019: field is deprecated, but still set on API < v1.44.
 		},
 		{
 			imageCtx: imageContext{i: types.ImageSummary{SharedSize: 10000}},
 			expValue: "10kB",
 			call:     ctx.SharedSize,
 		},
 		{
-			imageCtx: imageContext{i: types.ImageSummary{SharedSize: 5000, VirtualSize: 20000}},
+			imageCtx: imageContext{i: types.ImageSummary{SharedSize: 5000, Size: 20000}},
 			expValue: "15kB",
 			call:     ctx.UniqueSize,
 		},