fix(bridge): reject --dry-run on bridge commands

The bridge commands never go through the dry-run backend, so the
inherited --dry-run flag was silently ignored: `bridge convert` still
wiped and rewrote the output directory, pulled the transformer image
and ran it, and `bridge transformations create` still wrote its
destination folder.

Fail fast with an explicit error before any side effect instead of
pretending to honor the flag.

Signed-off-by: Guillaume Lours <[email protected]>

cmd/compose/bridge.go

@@ -63,13 +63,24 @@ func rejectUnknownSubcommand(cmd *cobra.Command, args []string) error {
 	}
 }
 
+// rejectDryRun is a PreRunE: bridge commands write to the local filesystem and
+// don't go through the dry-run backend, so honoring the flag silently would
+// still modify (or delete) files.
+func rejectDryRun(cmd *cobra.Command, _ []string) error {
+	if dryRun, _ := cmd.Flags().GetBool("dry-run"); dryRun {
+		return fmt.Errorf("--dry-run is not supported by %q", cmd.CommandPath())
+	}
+	return nil
+}
+
 func convertCommand(p *ProjectOptions, dockerCli command.Cli) *cobra.Command {
 	convertOpts := bridge.ConvertOptions{}
 	var assumeYes bool
 	cmd := &cobra.Command{
-		Use:   "convert",
-		Short: "Convert compose files to Kubernetes manifests, Helm charts, or another model",
-		Args:  cobra.NoArgs,
+		Use:     "convert",
+		Short:   "Convert compose files to Kubernetes manifests, Helm charts, or another model",
+		Args:    cobra.NoArgs,
+		PreRunE: rejectDryRun,
 		RunE: Adapt(func(ctx context.Context, args []string) error {
 			if assumeYes {
 				convertOpts.Confirm = func(string, bool) (bool, error) { return true, nil }
@@ -121,6 +132,7 @@ func listTransformersCommand(dockerCli command.Cli) *cobra.Command {
 		Aliases: []string{"ls"},
 		Short:   "List available transformations",
 		Args:    cobra.NoArgs,
+		PreRunE: rejectDryRun,
 		RunE: Adapt(func(ctx context.Context, args []string) error {
 			transformers, err := bridge.ListTransformers(ctx, dockerCli)
 			if err != nil {
@@ -171,9 +183,10 @@ func displayTransformer(dockerCli command.Cli, transformers []image.Summary, opt
 func createTransformerCommand(dockerCli command.Cli) *cobra.Command {
 	var opts bridge.CreateTransformerOptions
 	cmd := &cobra.Command{
-		Use:   "create [OPTION] PATH",
-		Short: "Create a new transformation",
-		Args:  cli.ExactArgs(1),
+		Use:     "create [OPTION] PATH",
+		Short:   "Create a new transformation",
+		Args:    cli.ExactArgs(1),
+		PreRunE: rejectDryRun,
 		RunE: Adapt(func(ctx context.Context, args []string) error {
 			opts.Dest = args[0]
 			return bridge.CreateTransformer(ctx, dockerCli, opts)

cmd/compose/bridge_test.go

@@ -18,6 +18,7 @@ package compose
 
 import (
 	"io"
+	"strings"
 	"testing"
 
 	"github.com/spf13/cobra"
@@ -93,3 +94,21 @@ func TestBridgeCommandsArgsValidation(t *testing.T) {
 		})
 	}
 }
+
+func TestBridgeCommandsRejectDryRun(t *testing.T) {
+	for _, args := range [][]string{
+		{"convert"},
+		{"transformations", "create", "dest"},
+		{"transformations", "list"},
+	} {
+		t.Run(strings.Join(args, " "), func(t *testing.T) {
+			root := &cobra.Command{Use: "compose", SilenceUsage: true, SilenceErrors: true}
+			root.PersistentFlags().Bool("dry-run", false, "")
+			root.AddCommand(bridgeCommand(&ProjectOptions{}, nil))
+			root.SetArgs(append([]string{"bridge", "--dry-run"}, args...))
+			root.SetOut(io.Discard)
+			root.SetErr(io.Discard)
+			assert.ErrorContains(t, root.Execute(), "--dry-run is not supported")
+		})
+	}
+}