github.com/urfave/cli v1.22.14: cli.NewApp cli.App Run with flags and subcommands

Clean-room public code sample — generation instructions

Write a brand-new, minimal, self-contained code sample in this clean-room directory.
Do not copy, paraphrase, or reference any existing project source. Work only from this spec.

A csx.json manifest scaffold already exists. Do not recreate it from memory. Preserve its case.goal, packages and symbols; fill its empty case.contract with exact assertions and correct its environment, commands and verifierAdapter for the files you generate.

Goal: cli.NewApp cli.App Run with flags and subcommands
Kind: HOW

Use EXACTLY these public packages and versions:
  - pkg:golang/github.com/urfave/cli@v1.22.14
Demonstrate these symbols/APIs:
  - cli.App.Run
  - cli.Command
  - cli.NewApp
  - cli.StringFlag
Constraints:
  - executionContext: node
Required runtime conditions:
  - ecosystem: npm
  - language: javascript
  - moduleSystem: cjs
  - packageManager: npm@10.9.8
  - runtime: node@22.23.2

Rules:
  - One focused purpose; the smallest project that proves the goal.
  - Include a contract test (test/contract.*) that runs OFFLINE and exits 0 exactly when the goal behavior works.
  - Pin every dependency with a lockfile so resolution is reproducible.
  - No secrets, credentials, or tokens. No real URLs (only example.com or localhost). No absolute paths.
  - No personal names, emails, company names, or project identifiers of any kind.
  - No binaries and no generated output (node_modules, dist, target, venv, .git, .env).
  - Keep it under 200 files and 256KB packed.

package main

import (
	"fmt"
	"os"

	"github.com/urfave/cli"
)

// NewGreeterApp builds a CLI application demonstrating cli.NewApp, Flags, and Commands.
func NewGreeterApp(actionFn func(name string) error, greetFn func(target string) error) *cli.App {
	app := cli.NewApp()
	app.Name = "greeter"
	app.Usage = "greeting CLI tool"
	app.Version = "1.0.0"

	app.Flags = []cli.Flag{
		cli.StringFlag{
			Name:  "name, n",
			Value: "world",
			Usage: "name to greet in default action",
		},
	}

	app.Action = func(c *cli.Context) error {
		name := c.String("name")
		if actionFn != nil {
			return actionFn(name)
		}
		fmt.Printf("Hello, %s!\n", name)
		return nil
	}

	app.Commands = []cli.Command{
		{
			Name:    "greet",
			Aliases: []string{"g"},
			Usage:   "greet a specific target",
			Flags: []cli.Flag{
				cli.StringFlag{
					Name:  "target, t",
					Value: "team",
					Usage: "target recipient of greeting",
				},
			},
			Action: func(c *cli.Context) error {
				target := c.String("target")
				if greetFn != nil {
					return greetFn(target)
				}
				fmt.Printf("Greetings to %s!\n", target)
				return nil
			},
		},
	}

	return app
}

func main() {
	app := NewGreeterApp(nil, nil)
	if err := app.Run(os.Args); err != nil {
		fmt.Fprintf(os.Stderr, "Error: %v\n", err)
		os.Exit(1)
	}
}

{"case":{"caseId":"case:sha256:99d32a283d53052b01c61ffb923cf8f8d0823d15d006d6f1b48c57bfdf07df7a","contract":["cli.NewApp initializes App","cli.App.Run parses StringFlag and runs root action","cli.App.Run parses StringFlag and runs subcommand action"],"goal":"cli.NewApp cli.App Run with flags and subcommands","kind":"HOW","packages":["pkg:golang/github.com/urfave/cli@v1.22.14"],"schemaVersion":1,"symbols":["cli.App.Run","cli.Command","cli.NewApp","cli.StringFlag"]},"contractCommand":["go","test","./..."],"environment":{"arch":"amd64","distro":"ubuntu","ecosystem":"golang","language":"go","languageVersion":"1.26.6","libc":"glibc","libcVersion":"2.39","moduleSystem":"go-mod","os":"linux","osVersionBucket":"24","packageManager":"go","packageManagerVersion":"1.26.6","runtime":"go","runtimeVersion":"1.26.6","schemaVersion":1},"license":"MIT-0","packages":["pkg:golang/github.com/urfave/cli@v1.22.14"],"schemaVersion":1,"subject":"pkg:golang/github.com/urfave/cli@v1.22.14","symbols":["cli.App.Run","cli.Command","cli.NewApp","cli.StringFlag"],"verifierAdapter":"golang@1"}

module test-urfave

go 1.26.6

require (
	github.com/cpuguy83/go-md2man/v2 v2.0.2 // indirect
	github.com/russross/blackfriday/v2 v2.1.0 // indirect
	github.com/urfave/cli v1.22.14 // indirect
)

github.com/BurntSushi/toml v1.3.2/go.mod h1:CxXYINrC8qIiEnFrOxCa7Jy5BFHlXnUU2pbicEuybxQ=
github.com/cpuguy83/go-md2man/v2 v2.0.2 h1:p1EgwI/C7NhT0JmVkwCD2ZBK8j4aeHQX2pMHHBfMQ6w=
github.com/cpuguy83/go-md2man/v2 v2.0.2/go.mod h1:tgQtvFlXSQOSOSIRvRPT7W67SCa46tRHOmNcaadrF8o=
github.com/davecgh/go-spew v1.1.0/go.mod h1:J7Y8YcW2NihsgmVo/mv3lAwl/skON4iLHjSsI+c5H38=
github.com/davecgh/go-spew v1.1.1/go.mod h1:J7Y8YcW2NihsgmVo/mv3lAwl/skON4iLHjSsI+c5H38=
github.com/pmezard/go-difflib v1.0.0/go.mod h1:iKH77koFhYxTK1pcRnkKkqfTogsbg7gZNVY4sRDYZ/4=
github.com/russross/blackfriday/v2 v2.1.0 h1:JIOH55/0cWyOuilr9/qlrm0BSXldqnqwMsf35Ld67mk=
github.com/russross/blackfriday/v2 v2.1.0/go.mod h1:+Rmxgy9KzJVeS9/2gXHxylqXiyQDYRxCVz55jmeOWTM=
github.com/stretchr/objx v0.1.0/go.mod h1:HFkY916IF+rwdDfMAkV7OtwuqBVzrE8GR6GFx+wExME=
github.com/stretchr/objx v0.4.0/go.mod h1:YvHI0jy2hoMjB+UWwv71VJQ9isScKT/TqJzVSSt89Yw=
github.com/stretchr/objx v0.5.0/go.mod h1:Yh+to48EsGEfYuaHDzXPcE3xhTkx73EhmCGUpEOglKo=
github.com/stretchr/testify v1.7.1/go.mod h1:6Fq8oRcR53rry900zMqJjRRixrwX3KX962/h/Wwjteg=
github.com/stretchr/testify v1.8.0/go.mod h1:yNjHg4UonilssWZ8iaSj1OCr/vHnekPRkoO+kdMU+MU=
github.com/stretchr/testify v1.8.4/go.mod h1:sz/lmYIOXD/1dqDmKjjqLyZ2RngseejIcXlSw2iwfAo=
github.com/urfave/cli v1.22.14 h1:ebbhrRiGK2i4naQJr+1Xj92HXZCrK7MsyTS/ob3HnAk=
github.com/urfave/cli v1.22.14/go.mod h1:X0eDS6pD6Exaclxm99NJ3FiCDRED7vIHpx2mDOHLvkA=
gopkg.in/check.v1 v0.0.0-20161208181325-20d25e280405/go.mod h1:Co6ibVJAznAaIkqp8huTwlJQCZ016jof/cbN4VW5Yz0=
gopkg.in/yaml.v2 v2.4.0/go.mod h1:RDklbk79AGWmwhnvt/jBztapEOGDOx6ZbXqjP6csGnQ=
gopkg.in/yaml.v3 v3.0.0-20200313102051-9f266ea9e77c/go.mod h1:K4uyk7z7BCEPqu6E+C64Yfv1cQ7kz7rIZviUmN+EgEM=
gopkg.in/yaml.v3 v3.0.1/go.mod h1:K4uyk7z7BCEPqu6E+C64Yfv1cQ7kz7rIZviUmN+EgEM=

{
  "schemaVersion": 1,
  "goal": "cli.NewApp cli.App Run with flags and subcommands",
  "kind": "HOW",
  "packages": [
    "pkg:golang/github.com/urfave/cli@v1.22.14"
  ],
  "symbols": [
    "cli.App.Run",
    "cli.Command",
    "cli.NewApp",
    "cli.StringFlag"
  ],
  "constraints": {
    "executionContext": "node"
  },
  "runtimeConditions": {
    "ecosystem": "npm",
    "language": "javascript",
    "moduleSystem": "cjs",
    "packageManager": "npm@10.9.8",
    "runtime": "node@22.23.2"
  }
}

package contract_test

import (
	"testing"

	"github.com/urfave/cli"
)

func TestContract_NewApp_Flags_Commands(t *testing.T) {
	app := cli.NewApp()
	if app == nil {
		t.Fatal("expected app to be non-nil")
	}
	app.Name = "test-app"

	var rootFlagVal string
	var rootExecuted bool

	app.Flags = []cli.Flag{
		cli.StringFlag{
			Name:  "config, c",
			Value: "default.yaml",
			Usage: "path to config file",
		},
	}

	app.Action = func(c *cli.Context) error {
		rootExecuted = true
		rootFlagVal = c.String("config")
		return nil
	}

	var subExecuted bool
	var subFlagVal string

	app.Commands = []cli.Command{
		{
			Name:    "run",
			Aliases: []string{"r"},
			Usage:   "run a task",
			Flags: []cli.Flag{
				cli.StringFlag{
					Name:  "env, e",
					Value: "production",
					Usage: "target environment",
				},
			},
			Action: func(c *cli.Context) error {
				subExecuted = true
				subFlagVal = c.String("env")
				return nil
			},
		},
	}

	// 1. Test root execution with custom flag
	err := app.Run([]string{"test-app", "--config", "custom.yaml"})
	if err != nil {
		t.Fatalf("unexpected error running root action: %v", err)
	}
	if !rootExecuted {
		t.Fatal("expected root action to execute")
	}
	if rootFlagVal != "custom.yaml" {
		t.Fatalf("expected root flag 'custom.yaml', got %q", rootFlagVal)
	}

	// 2. Test subcommand execution with custom flag
	err = app.Run([]string{"test-app", "run", "--env", "staging"})
	if err != nil {
		t.Fatalf("unexpected error running subcommand: %v", err)
	}
	if !subExecuted {
		t.Fatal("expected subcommand action to execute")
	}
	if subFlagVal != "staging" {
		t.Fatalf("expected subcommand flag 'staging', got %q", subFlagVal)
	}
}