Sort app image ls by created

Sorts apps by created date (if available) when running `app image ls`
with the latest created apps coming first.

Signed-off-by: Nick Adcock <nick.adcock@docker.com>

e2e/images_test.go

@@ -26,7 +26,7 @@ func assertImageListOutput(t *testing.T, cmd icmd.Cmd, expected string) {
 	stdout := result.Stdout()
 	match, err := regexp.MatchString(expected, stdout)
 	assert.NilError(t, err)
-	assert.Assert(t, match)
+	assert.Assert(t, match, expected, stdout)
 }
 
 func expectImageListOutput(t *testing.T, cmd icmd.Cmd, output string) {
@@ -222,24 +222,24 @@ c-simple-app        latest              [a-f0-9]{12}        simple
 		cmd.Command = dockerCli.Command("app", "build", "--tag", "push-pull", filepath.Join("testdata", "push-pull"))
 		icmd.RunCmd(cmd).Assert(t, icmd.Success)
 		expectImageListOutput(t, cmd, `REPOSITORY          TAG                 APP IMAGE ID        APP NAME            CREATED[ ]*
+push-pull           latest              [a-f0-9]{12}        push-pull           [La-z0-9 ]+ ago[ ]*
 a-simple-app        0.1                 [a-f0-9]{12}        simple              [La-z0-9 ]+ ago[ ]*
 a-simple-app        latest              [a-f0-9]{12}        simple              [La-z0-9 ]+ ago[ ]*
 b-simple-app        0.2                 [a-f0-9]{12}        simple              [La-z0-9 ]+ ago[ ]*
 b-simple-app        latest              [a-f0-9]{12}        simple              [La-z0-9 ]+ ago[ ]*
 c-simple-app        latest              [a-f0-9]{12}        simple              [La-z0-9 ]+ ago[ ]*
-push-pull           latest              [a-f0-9]{12}        push-pull           [La-z0-9 ]+ ago[ ]*
 `)
 
 		// can be tagged to an existing tag
 		dockerAppImageTag("push-pull", "b-simple-app:0.2")
 		icmd.RunCmd(cmd).Assert(t, icmd.Success)
 		expectImageListOutput(t, cmd, `REPOSITORY          TAG                 APP IMAGE ID        APP NAME            CREATED[ ]*
+b-simple-app        0.2                 [a-f0-9]{12}        push-pull           [La-z0-9 ]+ ago[ ]*
+push-pull           latest              [a-f0-9]{12}        push-pull           [La-z0-9 ]+ ago[ ]*
 a-simple-app        0.1                 [a-f0-9]{12}        simple              [La-z0-9 ]+ ago[ ]*
 a-simple-app        latest              [a-f0-9]{12}        simple              [La-z0-9 ]+ ago[ ]*
-b-simple-app        0.2                 [a-f0-9]{12}        push-pull           [La-z0-9 ]+ ago[ ]*
 b-simple-app        latest              [a-f0-9]{12}        simple              [La-z0-9 ]+ ago[ ]*
 c-simple-app        latest              [a-f0-9]{12}        simple              [La-z0-9 ]+ ago[ ]*
-push-pull           latest              [a-f0-9]{12}        push-pull           [La-z0-9 ]+ ago[ ]*
 `)
 	})
 }

internal/commands/image/list.go

@@ -1,6 +1,7 @@
 package image
 
 import (
+	"sort"
 	"time"
 
 	"github.com/docker/app/internal/packager"
@@ -60,6 +61,7 @@ func runList(dockerCli command.Cli, options imageListOption, bundleStore store.B
 		Format: NewImageFormat(options.format, options.quiet, options.digests),
 	}
 
+	sortImages(images)
 	return Write(ctx, images)
 }
 
@@ -92,6 +94,18 @@ func getImageID(bundle *relocated.Bundle, ref reference.Reference) (string, erro
 	return stringid.TruncateID(id.String()), nil
 }
 
+func sortImages(images []imageDesc) {
+	sort.SliceStable(images, func(i, j int) bool {
+		if images[i].Created.IsZero() {
+			return false
+		}
+		if images[j].Created.IsZero() {
+			return true
+		}
+		return images[i].Created.After(images[j].Created)
+	})
+}
+
 type imageDesc struct {
 	ID         string    `json:"id,omitempty"`
 	Name       string    `json:"name,omitempty"`

internal/commands/image/list_test.go

@@ -5,6 +5,7 @@ import (
 	"bytes"
 	"fmt"
 	"testing"
+	"time"
 
 	"github.com/docker/app/internal/relocated"
 
@@ -126,6 +127,22 @@ a855ac937f2e
 	}
 }
 
+func TestSortImages(t *testing.T) {
+	images := []imageDesc{
+		{ID: "1", Created: time.Date(2016, time.August, 15, 0, 0, 0, 0, time.UTC)},
+		{ID: "2"},
+		{ID: "3"},
+		{ID: "4", Created: time.Date(2018, time.August, 15, 0, 0, 0, 0, time.UTC)},
+		{ID: "5", Created: time.Date(2017, time.August, 15, 0, 0, 0, 0, time.UTC)},
+	}
+	sortImages(images)
+	assert.Equal(t, "4", images[0].ID)
+	assert.Equal(t, "5", images[1].ID)
+	assert.Equal(t, "1", images[2].ID)
+	assert.Equal(t, "2", images[3].ID)
+	assert.Equal(t, "3", images[4].ID)
+}
+
 func parseReference(t *testing.T, s string) reference.Reference {
 	ref, err := reference.Parse(s)
 	assert.NilError(t, err)