Use net.JoinHostPort() to fix formatting with IPv6 addresses

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

cli/command/container/port.go

@@ -3,6 +3,7 @@ package container
 import (
 	"context"
 	"fmt"
+	"net"
 	"strings"
 
 	"github.com/docker/cli/cli"
@@ -61,7 +62,7 @@ func runPort(dockerCli command.Cli, opts *portOptions) error {
 		}
 		if frontends, exists := c.NetworkSettings.Ports[newP]; exists && frontends != nil {
 			for _, frontend := range frontends {
-				fmt.Fprintf(dockerCli.Out(), "%s:%s\n", frontend.HostIP, frontend.HostPort)
+				fmt.Fprintln(dockerCli.Out(), net.JoinHostPort(frontend.HostIP, frontend.HostPort))
 			}
 			return nil
 		}
@@ -70,7 +71,7 @@ func runPort(dockerCli command.Cli, opts *portOptions) error {
 
 	for from, frontends := range c.NetworkSettings.Ports {
 		for _, frontend := range frontends {
-			fmt.Fprintf(dockerCli.Out(), "%s -> %s:%s\n", from, frontend.HostIP, frontend.HostPort)
+			fmt.Fprintf(dockerCli.Out(), "%s -> %s\n", from, net.JoinHostPort(frontend.HostIP, frontend.HostPort))
 		}
 	}
 

cli/command/container/port_test.go

@@ -0,0 +1,57 @@
+package container
+
+import (
+	"io/ioutil"
+	"testing"
+
+	"github.com/docker/cli/internal/test"
+	"github.com/docker/docker/api/types"
+	"github.com/docker/go-connections/nat"
+	"gotest.tools/v3/assert"
+	"gotest.tools/v3/golden"
+)
+
+func TestNewPortCommandOutput(t *testing.T) {
+	testCases := []struct {
+		name string
+		ips  []string
+	}{
+		{
+			name: "container-port-ipv4",
+			ips:  []string{"0.0.0.0"},
+		},
+		{
+			name: "container-port-ipv6",
+			ips:  []string{"::"},
+		},
+		{
+			name: "container-port-ipv6-and-ipv4",
+			ips:  []string{"::", "0.0.0.0"},
+		},
+	}
+	for _, tc := range testCases {
+		tc := tc
+		t.Run(tc.name, func(t *testing.T) {
+			cli := test.NewFakeCli(&fakeClient{
+				inspectFunc: func(string) (types.ContainerJSON, error) {
+					ci := types.ContainerJSON{NetworkSettings: &types.NetworkSettings{}}
+					ci.NetworkSettings.Ports = nat.PortMap{
+						"80/tcp": make([]nat.PortBinding, len(tc.ips)),
+					}
+					for i, ip := range tc.ips {
+						ci.NetworkSettings.Ports["80/tcp"][i] = nat.PortBinding{
+							HostIP: ip, HostPort: "3456",
+						}
+					}
+					return ci, nil
+				},
+			}, test.EnableContentTrust)
+			cmd := NewPortCommand(cli)
+			cmd.SetErr(ioutil.Discard)
+			cmd.SetArgs([]string{"some_container", "80"})
+			err := cmd.Execute()
+			assert.NilError(t, err)
+			golden.Assert(t, cli.OutBuffer().String(), tc.name+".golden")
+		})
+	}
+}

cli/command/container/testdata/container-port-ipv4.golden

@@ -0,0 +1 @@
+0.0.0.0:3456

cli/command/container/testdata/container-port-ipv6-and-ipv4.golden

@@ -0,0 +1,2 @@
+[::]:3456
+0.0.0.0:3456

cli/command/container/testdata/container-port-ipv6.golden

@@ -0,0 +1 @@
+[::]:3456