Remove ParseAndRun and update examples

Author: mfridman

README.md

@@ -69,13 +69,18 @@ root := &cli.Command{
 		return nil
 	},
 }
-if err := cli.ParseAndRun(context.Background(), root, os.Args[1:], nil); err != nil {
+if err := cli.Parse(root, os.Args[1:]); err != nil {
 	if errors.Is(err, flag.ErrHelp) {
+		fmt.Fprintf(os.Stdout, "%s\n", cli.DefaultUsage(root))
 		return
 	}
 	fmt.Fprintf(os.Stderr, "error: %v\n", err)
 	os.Exit(1)
 }
+if err := cli.Run(context.Background(), root, nil); err != nil {
+	fmt.Fprintf(os.Stderr, "error: %v\n", err)
+	os.Exit(1)
+}
 ```
 
 This code defines a simple `echo` command that echoes back the input. It supports a `-c` flag to

examples/cmd/echo/main.go

@@ -36,12 +36,16 @@ func main() {
 			return nil
 		},
 	}
-	if err := cli.ParseAndRun(context.Background(), root, os.Args[1:], nil); err != nil {
+	if err := cli.Parse(root, os.Args[1:]); err != nil {
 		if errors.Is(err, flag.ErrHelp) {
 			fmt.Fprintf(os.Stdout, "%s\n", cli.DefaultUsage(root))
 			return
 		}
 		fmt.Fprintf(os.Stderr, "error: %v\n", err)
 		os.Exit(1)
 	}
+	if err := cli.Run(context.Background(), root, nil); err != nil {
+		fmt.Fprintf(os.Stderr, "error: %v\n", err)
+		os.Exit(1)
+	}
 }

examples/cmd/task/main.go

@@ -50,20 +50,16 @@ func main() {
 		},
 	}
 
-	if err := cli.ParseAndRun(
-		context.Background(),
-		root,
-		os.Args[1:],
-		nil,
-	); err != nil {
+	if err := cli.Parse(root, os.Args[1:]); err != nil {
 		if errors.Is(err, flag.ErrHelp) {
 			fmt.Fprintf(os.Stdout, "%s\n", cli.DefaultUsage(root))
 			return
 		}
-		fmt.Fprintf(os.Stderr, "%s\n\nerror: %v\n",
-			cli.DefaultUsage(root),
-			err,
-		)
+		fmt.Fprintf(os.Stderr, "error: %v\n", err)
+		os.Exit(1)
+	}
+	if err := cli.Run(context.Background(), root, nil); err != nil {
+		fmt.Fprintf(os.Stderr, "error: %v\n", err)
 		os.Exit(1)
 	}
 }

run.go

@@ -8,25 +8,6 @@ import (
 	"os"
 )
 
-// ParseAndRun parses the command hierarchy and runs the command. A convenience function that
-// combines [Parse] and [Run] into a single call. See [Parse] and [Run] for more details.
-func ParseAndRun(ctx context.Context, root *Command, args []string, options *RunOptions) (retErr error) {
-	if err := Parse(root, args); err != nil {
-		return err
-	}
-	defer func() {
-		if r := recover(); r != nil {
-			switch err := r.(type) {
-			case error:
-				retErr = fmt.Errorf("internal: %v", err)
-			default:
-				retErr = fmt.Errorf("recovered: %v", r)
-			}
-		}
-	}()
-	return Run(ctx, root, options)
-}
-
 // RunOptions specifies options for running a command.
 type RunOptions struct {
 	// Stdin, Stdout, and Stderr are the standard input, output, and error streams for the command.
@@ -48,10 +29,30 @@ func Run(ctx context.Context, root *Command, options *RunOptions) error {
 	if root.state == nil || len(root.state.path) == 0 {
 		return errors.New("command has not been parsed")
 	}
+	cmd := root.terminal()
+	if cmd == nil {
+		// This should never happen, but if it does, it's likely a bug in the Parse function.
+		return errors.New("no terminal command found")
+	}
+
 	options = checkAndSetRunOptions(options)
 	updateState(root.state, options)
 
-	return root.terminal().Exec(ctx, root.state)
+	return run(ctx, cmd, root.state)
+}
+
+func run(ctx context.Context, cmd *Command, state *State) (retErr error) {
+	defer func() {
+		if r := recover(); r != nil {
+			switch err := r.(type) {
+			case error:
+				retErr = fmt.Errorf("internal: %v", err)
+			default:
+				retErr = fmt.Errorf("recover: %v", r)
+			}
+		}
+	}()
+	return cmd.Exec(ctx, state)
 }
 
 func updateState(s *State, opt *RunOptions) {

run_test.go

@@ -12,16 +12,12 @@ import (
 func TestRun(t *testing.T) {
 	t.Parallel()
 
-	t.Run("parse and run", func(t *testing.T) {
+	t.Run("print version", func(t *testing.T) {
 		t.Parallel()
-		var count int
 
 		root := &Command{
-			Name:  "count",
-			Usage: "count [flags] [command]",
-			Flags: FlagsFunc(func(fset *flag.FlagSet) {
-				fset.Bool("dry-run", false, "dry run")
-			}),
+			Name:  "printer",
+			Usage: "printer [flags] [command]",
 			SubCommands: []*Command{
 				{
 					Name:  "version",
@@ -32,35 +28,53 @@ func TestRun(t *testing.T) {
 					},
 				},
 			},
+			Exec: func(ctx context.Context, s *State) error { return nil },
+		}
+		err := Parse(root, []string{"version"})
+		require.NoError(t, err)
+
+		output := bytes.NewBuffer(nil)
+		require.NoError(t, err)
+		err = Run(context.Background(), root, &RunOptions{Stdout: output})
+		require.NoError(t, err)
+		require.Equal(t, "1.0.0\n", output.String())
+	})
+
+	t.Run("parse and run", func(t *testing.T) {
+		t.Parallel()
+		var count int
+
+		root := &Command{
+			Name:  "count",
+			Usage: "count [flags] [command]",
+			Flags: FlagsFunc(func(f *flag.FlagSet) {
+				f.Bool("dry-run", false, "dry run")
+			}),
 			Exec: func(ctx context.Context, s *State) error {
 				if !GetFlag[bool](s, "dry-run") {
 					count++
 				}
 				return nil
 			},
 		}
-
-		output := bytes.NewBuffer(nil)
-		err := ParseAndRun(context.Background(), root, []string{"version"}, &RunOptions{
-			Stdout: output,
-		})
+		err := Parse(root, nil)
 		require.NoError(t, err)
-		require.Equal(t, "1.0.0\n", output.String())
-		output.Reset()
-
 		// Run the command 3 times
 		for i := 0; i < 3; i++ {
-			err := ParseAndRun(context.Background(), root, nil, nil)
+			err := Run(context.Background(), root, nil)
 			require.NoError(t, err)
 		}
 		require.Equal(t, 3, count)
 		// Run with dry-run flag
-		err = ParseAndRun(context.Background(), root, []string{"--dry-run"}, nil)
+		err = Parse(root, []string{"--dry-run"})
+		require.NoError(t, err)
+		err = Run(context.Background(), root, nil)
 		require.NoError(t, err)
 		require.Equal(t, 3, count)
 	})
 	t.Run("typo suggestion", func(t *testing.T) {
 		t.Parallel()
+
 		root := &Command{
 			Name:  "count",
 			Usage: "count [flags] [command]",
@@ -77,7 +91,7 @@ func TestRun(t *testing.T) {
 			Exec: func(ctx context.Context, s *State) error { return nil },
 		}
 
-		err := ParseAndRun(context.Background(), root, []string{"verzion"}, nil)
+		err := Parse(root, []string{"verzion"})
 		require.Error(t, err)
 		require.Contains(t, err.Error(), `unknown command "verzion". Did you mean one of these?`)
 		require.Contains(t, err.Error(), `	version`)