cmd/docker: don't discard cli.StatusError errors without custom message

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

Author: thaJeztah

cmd/docker/docker.go

@@ -48,16 +48,15 @@ func dockerMain() int {
 	otel.SetErrorHandler(debug.OTELErrorHandler)
 
 	if err := runDocker(ctx, dockerCli); err != nil {
-		if sterr, ok := err.(cli.StatusError); ok {
-			if sterr.Status != "" {
-				fmt.Fprintln(dockerCli.Err(), sterr.Status)
-			}
+		var stErr cli.StatusError
+		if errors.As(err, &stErr) {
 			// StatusError should only be used for errors, and all errors should
 			// have a non-zero exit status, so never exit with 0
-			if sterr.StatusCode == 0 {
-				return 1
+			if stErr.StatusCode == 0 { // FIXME(thaJeztah): StatusCode should never be used with a zero status-code. Check if we do this anywhere.
+				stErr.StatusCode = 1
 			}
-			return sterr.StatusCode
+			_, _ = fmt.Fprintln(dockerCli.Err(), stErr)
+			return stErr.StatusCode
 		}
 		if errdefs.IsCancelled(err) {
 			return 0

e2e/cli-plugins/socket_test.go

@@ -203,7 +203,7 @@ func TestPluginSocketCommunication(t *testing.T) {
 
 			// the plugin does not get signalled, but it does get its
 			// context canceled by the CLI through the socket
-			const expected = "test-socket: exiting after context was done"
+			const expected = "test-socket: exiting after context was done\nexit status 2"
 			actual := strings.TrimSpace(string(out))
 			assert.Check(t, is.Equal(actual, expected))
 		})