cli/command/completion: ContainerNames: skip legacy link names

Inline StripNamePrefix and skip legacy links for completion.
Legacy links can be removed from a container, but only when
using `docker [container] rm --link <link-name>`.

When linking containers through legacy links, a container can get multiple
names; its own name, and a name for each link it's providing:

    # create two containers with links between them

    docker run -d --name one nginx:alpine
    docker run -d --name two --link one:link1 --link one:link2 --link one:link3 nginx:alpine

    # container "one" now has multiple names
    docker ps --no-trunc --format '{{.Names}}'
    two
    one,two/link1,two/link2,two/link3

    # running `docker rm --link` with a link-name removes a link:

    docker rm --link two/link3
    docker ps --no-trunc --format '{{.Names}}'
    two
    one,two/link1,two/link2

    # but without `--link`, it resolves the linked container and removes it:
    docker rm -fv two/link2
    two/link2
    docker ps --no-trunc --format '{{.Names}}'
    two

Legacy links are deprecated, and this can be confusing, so let's not provide
completion for secondary names.

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

Author: thaJeztah

cli/command/completion/functions.go

@@ -5,7 +5,6 @@ import (
 	"strings"
 
 	"github.com/distribution/reference"
-	"github.com/docker/cli/cli/command/formatter"
 	"github.com/moby/moby/api/types/container"
 	"github.com/moby/moby/client"
 	"github.com/spf13/cobra"
@@ -101,7 +100,13 @@ func ContainerNames(dockerCLI APIClientProvider, all bool, filters ...func(conta
 			if showContainerIDs {
 				names = append(names, ctr.ID)
 			}
-			names = append(names, formatter.StripNamePrefix(ctr.Names)...)
+			for _, n := range ctr.Names {
+				// Skip legacy link names: "/linked-container/link-name"
+				if len(n) <= 1 || strings.IndexByte(n[1:], '/') != -1 {
+					continue
+				}
+				names = append(names, strings.TrimPrefix(n, "/"))
+			}
 		}
 		return names, cobra.ShellCompDirectiveNoFileComp
 	}

cli/command/completion/functions_test.go

@@ -84,7 +84,7 @@ func TestCompleteContainerNames(t *testing.T) {
 				{ID: "id-b", State: container.StateCreated, Names: []string{"/container-b"}},
 				{ID: "id-a", State: container.StateExited, Names: []string{"/container-a"}},
 			},
-			expOut:       []string{"container-c", "container-c/link-b", "container-b", "container-a"},
+			expOut:       []string{"container-c", "container-b", "container-a"},
 			expOpts:      client.ContainerListOptions{All: true},
 			expDirective: cobra.ShellCompDirectiveNoFileComp,
 		},
@@ -97,7 +97,7 @@ func TestCompleteContainerNames(t *testing.T) {
 				{ID: "id-b", State: container.StateCreated, Names: []string{"/container-b"}},
 				{ID: "id-a", State: container.StateExited, Names: []string{"/container-a"}},
 			},
-			expOut:       []string{"id-c", "container-c", "container-c/link-b", "id-b", "container-b", "id-a", "container-a"},
+			expOut:       []string{"id-c", "container-c", "id-b", "container-b", "id-a", "container-a"},
 			expOpts:      client.ContainerListOptions{All: true},
 			expDirective: cobra.ShellCompDirectiveNoFileComp,
 		},
@@ -107,7 +107,7 @@ func TestCompleteContainerNames(t *testing.T) {
 			containers: []container.Summary{
 				{ID: "id-c", State: container.StateRunning, Names: []string{"/container-c", "/container-c/link-b"}},
 			},
-			expOut:       []string{"container-c", "container-c/link-b"},
+			expOut:       []string{"container-c"},
 			expDirective: cobra.ShellCompDirectiveNoFileComp,
 		},
 		{
@@ -117,7 +117,7 @@ func TestCompleteContainerNames(t *testing.T) {
 				func(ctr container.Summary) bool { return ctr.State == container.StateCreated },
 			},
 			containers: []container.Summary{
-				{ID: "id-c", State: container.StateRunning, Names: []string{"/container-c", "/container-c/link-b"}},
+				{ID: "id-c", State: container.StateRunning, Names: []string{"/container-c"}},
 				{ID: "id-b", State: container.StateCreated, Names: []string{"/container-b"}},
 				{ID: "id-a", State: container.StateExited, Names: []string{"/container-a"}},
 			},
@@ -133,7 +133,7 @@ func TestCompleteContainerNames(t *testing.T) {
 				func(ctr container.Summary) bool { return ctr.State == container.StateCreated },
 			},
 			containers: []container.Summary{
-				{ID: "id-c", State: container.StateRunning, Names: []string{"/container-c", "/container-c/link-b"}},
+				{ID: "id-c", State: container.StateRunning, Names: []string{"/container-c"}},
 				{ID: "id-b", State: container.StateCreated, Names: []string{"/container-b"}},
 				{ID: "id-a", State: container.StateCreated, Names: []string{"/container-a"}},
 			},