feat(mcpx): cli.Run in-process entrypoint, slim main (#1980 stage 1)

pkgs/mcpx/cmd/mcpx/main.go

@@ -3,17 +3,11 @@ package main
 
 import (
 	"context"
-	"errors"
-	"flag"
-	"fmt"
 	"os"
 	"os/signal"
-	"strings"
 	"syscall"
 
 	"github.com/dezren39/mcpx/internal/cli"
-	"github.com/dezren39/mcpx/internal/config"
-	"github.com/dezren39/mcpx/internal/daemon"
 )
 
 // version is overridden at build time with -ldflags "-X main.version=...".
@@ -23,180 +17,13 @@ import (
 // instead of impersonating one.
 var version = "0.0.0-dev"
 
-// splitList accepts comma or space separated values.
-func splitList(s string) []string {
-	return strings.FieldsFunc(s, func(r rune) bool { return r == ',' || r == ' ' })
-}
-
-// looksRunnable reports whether a bare first argument should be run, and as
-// what. It is deliberately conservative: a bare word that is not a file is
-// left to fail as an unknown command, because guessing that `mcpx serach` was
-// a snippet would replace a clear error with a baffling one.
-func looksRunnable(arg string) string {
-	if arg == "" || strings.HasPrefix(arg, "-") {
-		return ""
-	}
-	for _, ext := range []string{".ts", ".js", ".mts", ".mjs"} {
-		if strings.HasSuffix(arg, ext) {
-			return "file"
-		}
-	}
-	// Deliberately narrow. An "=" alone is not evidence of source -- a
-	// mistyped flag has one -- and treating it as such would run a typo as a
-	// program. These markers do not occur in a command name.
-	if strings.ContainsAny(arg, "(){};") || strings.Contains(arg, "await ") ||
-		strings.Contains(arg, "console.") || strings.Contains(arg, "tools.") ||
-		strings.Contains(arg, "=>") {
-		return "source"
-	}
-	if st, err := os.Stat(arg); err == nil && !st.IsDir() {
-		return "file"
-	}
-	return ""
-}
-
+// main is only signal setup plus the in-process entrypoint (#1980,
+// stage 1): everything it used to do inline -- global flags, dispatch,
+// exit codes -- lives in cli.Run, where a test can drive it.
 func main() {
 	ctx, stop := signal.NotifyContext(context.Background(), syscall.SIGINT, syscall.SIGTERM)
 	defer stop()
 
-	app := &cli.App{Version: version, Paths: daemon.ResolvePaths()}
-	// Script resolution is reached from places that do not carry an App, so
-	// it is told once where to read settings from.
-	cli.SetPlumbingSource(app)
-
-	args := os.Args[1:]
-	// Global flags may appear before the subcommand.
-	for len(args) > 0 && strings.HasPrefix(args[0], "-") {
-		switch {
-		case args[0] == "--json":
-			app.JSON = true
-			args = args[1:]
-		case args[0] == "--tui":
-			// A global flag as well as a subcommand, because it is as likely
-			// to be reached for mid-command ("...actually, show me") as
-			// chosen up front.
-			if err := app.CmdTUI(ctx, nil); err != nil {
-				fmt.Fprintln(os.Stderr, "mcpx:", err)
-				os.Exit(1)
-			}
-			return
-		case args[0] == "--profile" && len(args) > 1:
-			app.Profile.Names = append(app.Profile.Names, splitList(args[1])...)
-			args = args[2:]
-		case strings.HasPrefix(args[0], "--profile="):
-			app.Profile.Names = append(app.Profile.Names, splitList(strings.TrimPrefix(args[0], "--profile="))...)
-			args = args[1:]
-		case args[0] == "--skip-default":
-			app.Profile.SkipDefault = true
-			args = args[1:]
-		case args[0] == "--all-profiles":
-			app.Profile.All = true
-			args = args[1:]
-		case args[0] == "--config" && len(args) > 1:
-			app.ConfigPath = args[1]
-			args = args[2:]
-		case strings.HasPrefix(args[0], "--config="):
-			app.ConfigPath = strings.TrimPrefix(args[0], "--config=")
-			args = args[1:]
-		case args[0] == "--paths-config" && len(args) > 1:
-			// A bootstrap flag like --config: it decides which files
-			// the settings are read from, so it is captured here,
-			// before any settings exist (issue #1842).
-			config.SetPathsConfigSeed(splitList(args[1]))
-			args = args[2:]
-		case strings.HasPrefix(args[0], "--paths-config="):
-			config.SetPathsConfigSeed(splitList(strings.TrimPrefix(args[0], "--paths-config=")))
-			args = args[1:]
-		case args[0] == "--version" || args[0] == "-v":
-			fmt.Println("mcpx", version)
-			return
-		case args[0] == "--help" || args[0] == "-h":
-			_ = app.CmdHelp(ctx, nil)
-			return
-		default:
-			// Any setting every command accepts is also a global flag, so
-			// `mcpx --plumbing-strict-unknown-keys ls` means what
-			// `mcpx ls --plumbing-strict-unknown-keys` does.
-			rest, err := app.ApplyGlobalSettingFlags(args)
-			if err != nil {
-				fmt.Fprintln(os.Stderr, "mcpx:", err)
-				os.Exit(2)
-			}
-			if len(rest) < len(args) {
-				args = rest
-				continue
-			}
-			fmt.Fprintf(os.Stderr, "unknown global flag %q\n", args[0])
-			os.Exit(2)
-		}
-	}
-
-	if len(args) == 0 {
-		// Bare `mcpx` opens the browser when there is a terminal to draw on,
-		// and prints help when there is not. Help was the old behaviour and
-		// is still the right answer for a pipe; for a person at a prompt,
-		// a wall of usage is a worse first impression than the thing itself.
-		if err := app.CmdTUI(ctx, nil); err != nil {
-			_ = app.CmdHelp(ctx, nil)
-		}
-		return
-	}
-
-	cmd, rest := args[0], args[1:]
-	// The table lives in the cli package, beside Commands(), so a test can
-	// hold the two together; here it drifted from the declared list by seven.
-	handlers := app.Handlers()
-
-	h, ok := handlers[cmd]
-	if !ok {
-		// An argument that is obviously a script or a snippet runs, rather
-		// than being refused for not being a subcommand. The alternative --
-		// insisting on `mcpx run` -- rejects the most natural thing to type
-		// in order to protect a namespace that has no collisions in it.
-		if kind := looksRunnable(cmd); kind != "" {
-			if kind == "file" {
-				h, rest = app.CmdRun, args
-			} else {
-				h, rest = app.CmdExec, args
-			}
-		} else {
-			fmt.Fprintf(os.Stderr, "unknown command %q\n\n", cmd)
-			_ = app.CmdHelp(ctx, nil)
-			os.Exit(2)
-		}
-	}
-
-	// Settings are resolved before dispatch, so a contradiction in a config
-	// file is reported once, up front, rather than by whichever command
-	// happens to read the offending value first.
-	if err := app.SettingsErr(); err != nil {
-		fmt.Fprintln(os.Stderr, "mcpx:", err)
-		os.Exit(2)
-	}
-
-	// An in-process daemon lives exactly as long as this command. Stopped on
-	// every exit path, including an error, or its servers would outlive the
-	// process that owns them.
-	defer app.CloseInline()
-
-	if err := h(ctx, rest); err != nil {
-		// Help was asked for and already printed; it is not a failure.
-		// Commands reached without the dispatch table (a script file named
-		// on the command line) can still return this directly.
-		if errors.Is(err, flag.ErrHelp) {
-			return
-		}
-		var ec cli.ExitCoder
-		if errors.As(err, &ec) {
-			fmt.Fprintln(os.Stderr, "mcpx:", err)
-			app.CloseInline()
-			os.Exit(ec.ExitCode())
-		}
-		if errors.Is(err, cli.ErrNoDaemon) {
-			fmt.Fprintln(os.Stderr, "mcpx: daemon is not running and could not be started")
-		} else {
-			fmt.Fprintln(os.Stderr, "mcpx:", err)
-		}
-		os.Exit(1)
-	}
+	cli.Version = version
+	os.Exit(cli.Run(ctx, os.Args[1:], cli.Env(os.Environ()), cli.Stdio{In: os.Stdin, Out: os.Stdout, Err: os.Stderr}))
 }

pkgs/mcpx/internal/cli/commands.go

@@ -68,6 +68,11 @@ type App struct {
 	// Used by the MCP server, which must return what a script produced
 	// rather than write it to a stream the host is parsing as protocol.
 	stdoutOverride interface{ Write([]byte) (int, error) }
+	// environ is the environment Run was invoked with, recorded at the
+	// entrypoint for stage 2 of #1980 (threading it through ResolvePaths,
+	// settings.Environ and the plumbing source). Nil when the App was
+	// built directly; Environ() then falls back to os.Environ().
+	environ Env
 	settingsState
 }
 
@@ -1132,7 +1137,7 @@ func (a *App) runScript(ctx context.Context, args []string, inline bool) error {
 			return err
 		}
 		if res.ExitCode != 0 {
-			os.Exit(res.ExitCode)
+			return &exitStatusError{code: res.ExitCode}
 		}
 		return nil
 	}
@@ -1172,7 +1177,7 @@ func (a *App) runScript(ctx context.Context, args []string, inline bool) error {
 		a.reportArtifacts(res)
 	}
 	if res.ExitCode != 0 {
-		os.Exit(res.ExitCode)
+		return &exitStatusError{code: res.ExitCode}
 	}
 	return nil
 }

pkgs/mcpx/internal/cli/exec.go

@@ -349,7 +349,7 @@ func (a *App) renderExecResult(res *execsvc.Result, eo execOptions) error {
 		if res.Error != "" {
 			fmt.Fprintln(os.Stderr, "mcpx:", res.Error)
 		}
-		os.Exit(res.ExitCode)
+		return &exitStatusError{code: res.ExitCode}
 	}
 	return nil
 }