cmd: expose MakeMain() for testing

I'd like to add the kargo-demo repository to Unity to test evalv3, but
can't get a handle on the main function to wire up to testscript.

This patch fixes the problem by moving the MakeMain function to a public
package so the kargo-demo go module can import and call it using the go
mod tools technique.

cmd/cmd.go

@@ -0,0 +1,63 @@
+package cmd
+
+import (
+	"context"
+	"fmt"
+	"log/slog"
+	"os"
+	"runtime/pprof"
+	"runtime/trace"
+
+	"github.com/holos-run/holos/internal/cli"
+	"github.com/holos-run/holos/internal/holos"
+)
+
+// MakeMain makes a main function for the cli or tests.
+func MakeMain(options ...holos.Option) func() int {
+	return func() (exitCode int) {
+		cfg := holos.New(options...)
+		slog.SetDefault(cfg.Logger())
+		ctx := context.Background()
+
+		if format := os.Getenv("HOLOS_CPU_PROFILE"); format != "" {
+			f, _ := os.Create(fmt.Sprintf(format, os.Getppid(), os.Getpid()))
+			err := pprof.StartCPUProfile(f)
+			defer func() {
+				pprof.StopCPUProfile()
+				f.Close()
+			}()
+			if err != nil {
+				return cli.HandleError(ctx, err, cfg)
+			}
+		}
+		defer memProfile(ctx, cfg)
+
+		if format := os.Getenv("HOLOS_TRACE"); format != "" {
+			f, _ := os.Create(fmt.Sprintf(format, os.Getppid(), os.Getpid()))
+			err := trace.Start(f)
+			defer func() {
+				trace.Stop()
+				f.Close()
+			}()
+			if err != nil {
+				return cli.HandleError(ctx, err, cfg)
+			}
+		}
+
+		feature := &holos.EnvFlagger{}
+		if err := cli.New(cfg, feature).ExecuteContext(ctx); err != nil {
+			return cli.HandleError(ctx, err, cfg)
+		}
+		return 0
+	}
+}
+
+func memProfile(ctx context.Context, cfg *holos.Config) {
+	if format := os.Getenv("HOLOS_MEM_PROFILE"); format != "" {
+		f, _ := os.Create(fmt.Sprintf(format, os.Getppid(), os.Getpid()))
+		defer f.Close()
+		if err := pprof.WriteHeapProfile(f); err != nil {
+			_ = cli.HandleError(ctx, err, cfg)
+		}
+	}
+}

cmd/holos/main.go

@@ -3,9 +3,9 @@ package main
 import (
 	"os"
 
-	"github.com/holos-run/holos/internal/cli"
+	"github.com/holos-run/holos/cmd"
 )
 
 func main() {
-	os.Exit(cli.MakeMain()())
+	os.Exit(cmd.MakeMain()())
 }

cmd/holos/main_test.go

@@ -6,13 +6,13 @@ import (
 	"testing"
 
 	cue "cuelang.org/go/cmd/cue/cmd"
-	"github.com/holos-run/holos/internal/cli"
+	"github.com/holos-run/holos/cmd"
 	"github.com/rogpeppe/go-internal/testscript"
 )
 
 func TestMain(m *testing.M) {
 	os.Exit(testscript.RunMain(m, map[string]func() int{
-		"holos": cli.MakeMain(),
+		"holos": cmd.MakeMain(),
 		"cue":   cue.Main,
 	}))
 }

internal/cli/main.go

@@ -1,110 +1 @@
 package cli
-
-import (
-	"context"
-	"fmt"
-	"log/slog"
-	"os"
-	"runtime/pprof"
-	"runtime/trace"
-
-	"connectrpc.com/connect"
-	cue "cuelang.org/go/cue/errors"
-	"github.com/holos-run/holos/internal/errors"
-	"github.com/holos-run/holos/internal/holos"
-	"google.golang.org/genproto/googleapis/rpc/errdetails"
-)
-
-func memProfile(ctx context.Context, cfg *holos.Config) {
-	if format := os.Getenv("HOLOS_MEM_PROFILE"); format != "" {
-		f, _ := os.Create(fmt.Sprintf(format, os.Getppid(), os.Getpid()))
-		defer f.Close()
-		if err := pprof.WriteHeapProfile(f); err != nil {
-			_ = HandleError(ctx, err, cfg)
-		}
-	}
-}
-
-// MakeMain makes a main function for the cli or tests.
-func MakeMain(options ...holos.Option) func() int {
-	return func() (exitCode int) {
-		cfg := holos.New(options...)
-		slog.SetDefault(cfg.Logger())
-		ctx := context.Background()
-
-		if format := os.Getenv("HOLOS_CPU_PROFILE"); format != "" {
-			f, _ := os.Create(fmt.Sprintf(format, os.Getppid(), os.Getpid()))
-			err := pprof.StartCPUProfile(f)
-			defer func() {
-				pprof.StopCPUProfile()
-				f.Close()
-			}()
-			if err != nil {
-				return HandleError(ctx, err, cfg)
-			}
-		}
-		defer memProfile(ctx, cfg)
-
-		if format := os.Getenv("HOLOS_TRACE"); format != "" {
-			f, _ := os.Create(fmt.Sprintf(format, os.Getppid(), os.Getpid()))
-			err := trace.Start(f)
-			defer func() {
-				trace.Stop()
-				f.Close()
-			}()
-			if err != nil {
-				return HandleError(ctx, err, cfg)
-			}
-		}
-
-		feature := &holos.EnvFlagger{}
-		if err := New(cfg, feature).ExecuteContext(ctx); err != nil {
-			return HandleError(ctx, err, cfg)
-		}
-		return 0
-	}
-}
-
-// HandleError is the top level error handler that unwraps and logs errors.
-func HandleError(ctx context.Context, err error, hc *holos.Config) (exitCode int) {
-	// Connect errors have codes, log them.
-	log := hc.NewTopLevelLogger().With("code", connect.CodeOf(err))
-	var cueErr cue.Error
-	var errAt *errors.ErrorAt
-
-	if errors.As(err, &errAt) {
-		loc := errAt.Source.Loc()
-		err2 := errAt.Unwrap()
-		log.ErrorContext(ctx, fmt.Sprintf("could not run: %s at %s", err2, loc), "err", err2, "loc", loc)
-	} else {
-		log.ErrorContext(ctx, fmt.Sprintf("could not run: %s", err), "err", err)
-	}
-
-	// cue errors are bundled up as a list and refer to multiple files / lines.
-	if errors.As(err, &cueErr) {
-		msg := cue.Details(cueErr, nil)
-		if _, err := fmt.Fprint(hc.Stderr(), msg); err != nil {
-			log.ErrorContext(ctx, "could not write CUE error details: "+err.Error(), "err", err)
-		}
-	}
-	// connect errors have details and codes.
-	// Refer to https://connectrpc.com/docs/go/errors
-	if connectErr := new(connect.Error); errors.As(err, &connectErr) {
-		for _, detail := range connectErr.Details() {
-			msg, valueErr := detail.Value()
-			if valueErr != nil {
-				log.WarnContext(ctx, "could not decode error detail", "err", err, "type", detail.Type(), "note", "this usually means we don't have the schema for the protobuf message type")
-				continue
-			}
-			if info, ok := msg.(*errdetails.ErrorInfo); ok {
-				logDetail := log.With("reason", info.GetReason(), "domain", info.GetDomain())
-				for k, v := range info.GetMetadata() {
-					logDetail = logDetail.With(k, v)
-				}
-				logDetail.ErrorContext(ctx, info.String())
-			}
-		}
-	}
-
-	return 1
-}

internal/cli/root.go

@@ -1,14 +1,18 @@
 package cli
 
 import (
+	"context"
 	_ "embed"
 	"fmt"
 	"log/slog"
 
+	"connectrpc.com/connect"
 	"github.com/spf13/cobra"
+	"google.golang.org/genproto/googleapis/rpc/errdetails"
 
 	"github.com/holos-run/holos/version"
 
+	"github.com/holos-run/holos/internal/errors"
 	"github.com/holos-run/holos/internal/holos"
 	"github.com/holos-run/holos/internal/logger"
 	"github.com/holos-run/holos/internal/server"
@@ -28,7 +32,8 @@ import (
 	"github.com/holos-run/holos/internal/cli/token"
 	"github.com/holos-run/holos/internal/cli/txtar"
 
-	cue "cuelang.org/go/cmd/cue/cmd"
+	cueCmd "cuelang.org/go/cmd/cue/cmd"
+	cue_errors "cuelang.org/go/cue/errors"
 )
 
 //go:embed help.txt
@@ -119,7 +124,7 @@ func newOrgCmd(feature holos.Flagger) (cmd *cobra.Command) {
 
 func newCueCmd() (cmd *cobra.Command) {
 	// Get a handle on the cue root command fields.
-	root, _ := cue.New([]string{})
+	root, _ := cueCmd.New([]string{})
 	// Copy the fields to our embedded command.
 	cmd = command.New("cue")
 	cmd.Short = root.Short
@@ -130,8 +135,52 @@ func newCueCmd() (cmd *cobra.Command) {
 
 	// We do it this way so we handle errors correctly.
 	cmd.RunE = func(cmd *cobra.Command, args []string) error {
-		cueRootCommand, _ := cue.New(args)
+		cueRootCommand, _ := cueCmd.New(args)
 		return cueRootCommand.Run(cmd.Root().Context())
 	}
 	return cmd
 }
+
+// HandleError is the top level error handler that unwraps and logs errors.
+func HandleError(ctx context.Context, err error, hc *holos.Config) (exitCode int) {
+	// Connect errors have codes, log them.
+	log := hc.NewTopLevelLogger().With("code", connect.CodeOf(err))
+	var cueErr cue_errors.Error
+	var errAt *errors.ErrorAt
+
+	if errors.As(err, &errAt) {
+		loc := errAt.Source.Loc()
+		err2 := errAt.Unwrap()
+		log.ErrorContext(ctx, fmt.Sprintf("could not run: %s at %s", err2, loc), "err", err2, "loc", loc)
+	} else {
+		log.ErrorContext(ctx, fmt.Sprintf("could not run: %s", err), "err", err)
+	}
+
+	// cue errors are bundled up as a list and refer to multiple files / lines.
+	if errors.As(err, &cueErr) {
+		msg := cue_errors.Details(cueErr, nil)
+		if _, err := fmt.Fprint(hc.Stderr(), msg); err != nil {
+			log.ErrorContext(ctx, "could not write CUE error details: "+err.Error(), "err", err)
+		}
+	}
+	// connect errors have details and codes.
+	// Refer to https://connectrpc.com/docs/go/errors
+	if connectErr := new(connect.Error); errors.As(err, &connectErr) {
+		for _, detail := range connectErr.Details() {
+			msg, valueErr := detail.Value()
+			if valueErr != nil {
+				log.WarnContext(ctx, "could not decode error detail", "err", err, "type", detail.Type(), "note", "this usually means we don't have the schema for the protobuf message type")
+				continue
+			}
+			if info, ok := msg.(*errdetails.ErrorInfo); ok {
+				logDetail := log.With("reason", info.GetReason(), "domain", info.GetDomain())
+				for k, v := range info.GetMetadata() {
+					logDetail = logDetail.With(k, v)
+				}
+				logDetail.ErrorContext(ctx, info.String())
+			}
+		}
+	}
+
+	return 1
+}

version/embedded/patch

@@ -1 +1 @@
-7
+8