cmd/app: optionally override configured command

Useful for multiple applications sharing state.

Signed-off-by: Ophestra <cat@gensokyo.uk>

cmd/app/app.go

@@ -80,7 +80,7 @@ func parse(id string, base *check.Absolute, r io.Reader) (*hst.Config, error) {
 			Shell:    shell,
 			Home:     home,
 			Path:     shell,
-			Args:     []string{"zsh", "-c"},
+			Args:     []string{"zsh", "-ic"},
 
 			Flags: hst.FCoverRun,
 		},

cmd/app/app_test.go

@@ -118,7 +118,7 @@ talk com.canonical.Unity
 				Home:     hst.AbsPrivateTmp.Append("home"),
 				Path:     fhs.AbsRoot.Append("bin", "zsh"),
 				Args: []string{
-					"zsh", "-c",
+					"zsh", "-ic",
 					"exec Discord --ozone-platform-hint=wayland",
 				},
 

cmd/app/main.go

@@ -141,57 +141,71 @@ func main() {
 		)
 	}
 
-	c.NewCommand(
-		"run", "Start the named application",
-		func(args []string) error {
-			if len(args) != 1 {
-				dents, err := os.ReadDir(base.Append("app").String())
+	{
+		var (
+			flagCommand string
+		)
+		c.NewCommand(
+			"run", "Start the named application",
+			func(args []string) error {
+				if len(args) != 1 {
+					dents, err := os.ReadDir(base.Append("app").String())
+					if err != nil {
+						return err
+					}
+					for _, dent := range dents {
+						if dent.IsDir() {
+							continue
+						}
+						fmt.Println(dent.Name())
+					}
+					return nil
+				}
+
+				var config *hst.Config
+				var r io.Reader
+				f, err := os.Open(base.Append("app", args[0]).String())
 				if err != nil {
 					return err
 				}
-				for _, dent := range dents {
-					if dent.IsDir() {
-						continue
+				r = f
+
+				var common *os.File
+				if common, err = os.Open(base.Append("common").String()); err != nil {
+					if !errors.Is(err, os.ErrNotExist) {
+						_ = f.Close()
+						return err
 					}
-					fmt.Println(dent.Name())
+				} else {
+					r = io.MultiReader(f, common)
 				}
-				return nil
-			}
 
-			var config *hst.Config
-			var r io.Reader
-			f, err := os.Open(base.Append("app", args[0]).String())
-			if err != nil {
-				return err
-			}
-			r = f
-
-			var common *os.File
-			if common, err = os.Open(base.Append("common").String()); err != nil {
-				if !errors.Is(err, os.ErrNotExist) {
-					_ = f.Close()
-					return err
-				}
-			} else {
-				r = io.MultiReader(f, common)
-			}
-
-			config, err = parse(args[0], base, r)
-			if closeErr := f.Close(); err == nil {
-				err = closeErr
-			}
-			if common != nil {
-				if closeErr := common.Close(); err == nil {
+				config, err = parse(args[0], base, r)
+				if closeErr := f.Close(); err == nil {
 					err = closeErr
 				}
-			}
-			if err != nil {
-				return err
-			}
+				if common != nil {
+					if closeErr := common.Close(); err == nil {
+						err = closeErr
+					}
+				}
+				if err != nil {
+					return err
+				}
 
-			return run(ctx, msg, config)
-		},
-	)
+				if flagCommand != "" {
+					config.Container.Args[2] = flagCommand
+				}
+
+				return run(ctx, msg, config)
+			},
+		).
+			Flag(
+				&flagCommand,
+				"command", command.StringFlag(""),
+				"Override configured command",
+			)
+	}
 
 	c.MustParse(os.Args[1:], func(err error) {
 		if e, ok := errors.AsType[*exec.ExitError](err); ok && e != nil {