Fix detached sandbox exec stream handling

Author: cursoragent

pkg/cmd/sandbox/common.go

@@ -55,9 +55,9 @@ func snapshotRef(id string) *sandboxv1.SnapshotRef {
 }
 
 // consumeCommandEventStream drains a depot.sandbox.v1 CommandEvent stream
-// into stdout/stderr and returns the final exit code from Finished. The
-// stream shape mirrors RunCommand / RunCommandPipe / AttachCommand /
-// RunHook: Started -> Stdout/Stderr/Error/EvictedEarlyData* -> Finished.
+// into stdout/stderr and returns the final exit code from Finished. The stream
+// shape is generally Started -> Stdout/Stderr/Error/EvictedEarlyData* ->
+// Finished; detached RunCommand streams end cleanly after Started.
 //
 // EvictedEarlyData is reported on stderr as a single line so log consumers
 // see the gap; the stream continues afterward. Error frames are surfaced the
@@ -66,13 +66,16 @@ func snapshotRef(id string) *sandboxv1.SnapshotRef {
 func consumeCommandEventStream(
 	stream *connect.ServerStreamForClient[sandboxv1.CommandEvent],
 	stdout, stderr io.Writer,
+	allowMissingFinished bool,
 ) (exitCode int32, err error) {
 	defer func() { _ = stream.Close() }()
+	sawStarted := false
 	for stream.Receive() {
 		msg := stream.Msg()
 		switch ev := msg.Event.(type) {
 		case *sandboxv1.CommandEvent_Started_:
 			// metadata only — nothing to print
+			sawStarted = true
 		case *sandboxv1.CommandEvent_Stdout:
 			if ev.Stdout != nil && len(ev.Stdout.Data) > 0 {
 				_, _ = stdout.Write(ev.Stdout.Data)
@@ -99,6 +102,9 @@ func consumeCommandEventStream(
 	if err := stream.Err(); err != nil && !errors.Is(err, io.EOF) {
 		return 0, fmt.Errorf("command stream: %w", err)
 	}
+	if allowMissingFinished && sawStarted {
+		return 0, nil
+	}
 	// Stream closed without a Finished event. Treat this as an error rather
 	// than silently reporting exit 0 — a clean disconnect mid-command is
 	// indistinguishable from a real exit-0 completion to the caller otherwise.

pkg/cmd/sandbox/exec.go

@@ -3,6 +3,7 @@ package sandbox
 import (
 	"fmt"
 	"os"
+	"strings"
 
 	"connectrpc.com/connect"
 	"github.com/depot/cli/pkg/api"
@@ -88,7 +89,7 @@ parsing stops there.`,
 				return fmt.Errorf("run command: %w", err)
 			}
 
-			exit, err := consumeCommandEventStream(stream, os.Stdout, os.Stderr)
+			exit, err := consumeCommandEventStream(stream, os.Stdout, os.Stderr, detached)
 			if err != nil {
 				return err
 			}
@@ -119,20 +120,11 @@ func parseEnvSlice(in []string) (map[string]string, error) {
 	}
 	out := make(map[string]string, len(in))
 	for _, e := range in {
-		k, v, ok := splitKV(e)
+		k, v, ok := strings.Cut(e, "=")
 		if !ok {
 			return nil, fmt.Errorf("invalid env format %q, expected KEY=VALUE", e)
 		}
 		out[k] = v
 	}
 	return out, nil
 }
-
-func splitKV(s string) (string, string, bool) {
-	for i := 0; i < len(s); i++ {
-		if s[i] == '=' {
-			return s[:i], s[i+1:], true
-		}
-	}
-	return "", "", false
-}

pkg/cmd/sandbox/hooks.go

@@ -149,7 +149,7 @@ func runHook(ctx context.Context, client sandboxv1connect.SandboxServiceClient,
 		return fmt.Errorf("exec: %w", err)
 	}
 
-	exit, err := consumeCommandEventStream(stream, stdout, stderr)
+	exit, err := consumeCommandEventStream(stream, stdout, stderr, false)
 	if err != nil {
 		return err
 	}