feat(bootstrap): add command alias expansion

bootstrap/bootstrap.go

@@ -47,6 +47,7 @@ type Options struct {
 	BinaryName  string
 	Description string
 	Version     string
+	Aliases     map[string][]string
 	Args        []string
 	Stdin       io.Reader
 	Stdout      io.Writer
@@ -113,7 +114,7 @@ func Run(ctx context.Context, opts Options) error {
 		return ErrBinaryNameRequired
 	}
 
-	command, commandArgs, showHelp := parseArgs(normalized.Args)
+	command, commandArgs, showHelp := parseArgs(expandAliases(normalized.Args, normalized.Aliases))
 	if showHelp {
 		return printHelp(normalized, command, commandArgs)
 	}
@@ -168,6 +169,7 @@ func normalize(opts Options) Options {
 }
 
 func parseArgs(args []string) (command string, commandArgs []string, showHelp bool) {
+	args = trimArgs(args)
 	if len(args) == 0 {
 		return "", nil, false
 	}
@@ -193,6 +195,63 @@ func parseArgs(args []string) (command string, commandArgs []string, showHelp bo
 	return command, commandArgs, false
 }
 
+func expandAliases(args []string, aliases map[string][]string) []string {
+	args = trimArgs(args)
+	if len(args) == 0 || len(aliases) == 0 {
+		return args
+	}
+
+	if args[0] == "help" && len(args) > 1 {
+		expanded, ok := resolveAlias(aliases, args[1])
+		if !ok {
+			return args
+		}
+
+		withHelp := make([]string, 0, 1+len(expanded)+len(args[2:]))
+		withHelp = append(withHelp, "help")
+		withHelp = append(withHelp, expanded...)
+		withHelp = append(withHelp, args[2:]...)
+		return withHelp
+	}
+
+	expanded, ok := resolveAlias(aliases, args[0])
+	if !ok {
+		return args
+	}
+
+	withCommand := make([]string, 0, len(expanded)+len(args[1:]))
+	withCommand = append(withCommand, expanded...)
+	withCommand = append(withCommand, args[1:]...)
+
+	if len(withCommand) == 0 {
+		return args
+	}
+
+	last := strings.TrimSpace(withCommand[len(withCommand)-1])
+	if last != "-h" && last != "--help" {
+		return withCommand
+	}
+
+	helpArgs := make([]string, 0, len(withCommand))
+	helpArgs = append(helpArgs, "help")
+	helpArgs = append(helpArgs, withCommand[:len(withCommand)-1]...)
+	return helpArgs
+}
+
+func resolveAlias(aliases map[string][]string, command string) ([]string, bool) {
+	target, ok := aliases[strings.TrimSpace(command)]
+	if !ok {
+		return nil, false
+	}
+
+	expanded := trimArgs(target)
+	if len(expanded) == 0 {
+		return nil, false
+	}
+
+	return expanded, true
+}
+
 func trimArgs(args []string) []string {
 	if len(args) == 0 {
 		return nil

bootstrap/bootstrap_test.go

@@ -319,3 +319,82 @@ func TestRunConfigReturnsUnknownSubcommand(t *testing.T) {
 		t.Fatalf("Run error = %v, want ErrUnknownSubcommand", err)
 	}
 }
+
+func TestRunRoutesAliasToConfigSubcommandHook(t *testing.T) {
+	var stdout bytes.Buffer
+	var stderr bytes.Buffer
+	var got Invocation
+
+	err := Run(context.Background(), Options{
+		BinaryName: "my-mcp",
+		Aliases: map[string][]string{
+			"doctor": {CommandConfig, ConfigSubcommandTest},
+		},
+		Args:   []string{"doctor", "--profile", "work"},
+		Stdout: &stdout,
+		Stderr: &stderr,
+		Hooks: Hooks{
+			ConfigTest: func(_ context.Context, inv Invocation) error {
+				got = inv
+				return nil
+			},
+		},
+	})
+	if err != nil {
+		t.Fatalf("Run error = %v", err)
+	}
+
+	if got.Command != "config test" {
+		t.Fatalf("invocation command = %q, want %q", got.Command, "config test")
+	}
+	wantArgs := []string{"--profile", "work"}
+	if !slices.Equal(got.Args, wantArgs) {
+		t.Fatalf("invocation args = %v, want %v", got.Args, wantArgs)
+	}
+}
+
+func TestRunPrintsAliasHelpFromHelpCommand(t *testing.T) {
+	var stdout bytes.Buffer
+	var stderr bytes.Buffer
+
+	err := Run(context.Background(), Options{
+		BinaryName: "my-mcp",
+		Aliases: map[string][]string{
+			"doctor": {CommandConfig, ConfigSubcommandTest},
+		},
+		Args:   []string{"help", "doctor"},
+		Stdout: &stdout,
+		Stderr: &stderr,
+	})
+	if err != nil {
+		t.Fatalf("Run error = %v", err)
+	}
+
+	text := stdout.String()
+	if !strings.Contains(text, "my-mcp config test [args]") {
+		t.Fatalf("command help output = %q", text)
+	}
+}
+
+func TestRunPrintsAliasHelpFromTrailingHelpFlag(t *testing.T) {
+	var stdout bytes.Buffer
+	var stderr bytes.Buffer
+
+	err := Run(context.Background(), Options{
+		BinaryName: "my-mcp",
+		Aliases: map[string][]string{
+			"doctor": {CommandConfig, ConfigSubcommandTest},
+		},
+		Args:   []string{"doctor", "--help"},
+		Stdout: &stdout,
+		Stderr: &stderr,
+	})
+	if err != nil {
+		t.Fatalf("Run error = %v", err)
+	}
+
+	text := stdout.String()
+	if !strings.Contains(text, "my-mcp config test [args]") {
+		t.Fatalf("command help output = %q", text)
+	}
+}