github.com/spf13/cast v1.4.1: ToDuration

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: verify github.com/spf13/cast.ToDuration in pkg:golang/github.com/spf13/cast@v1.4.1
Kind: HOW

Use EXACTLY these public packages and versions:
  - pkg:golang/github.com/spf13/cast@v1.4.1
Demonstrate these symbols/APIs:
  - github.com/spf13/cast.ToDuration

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.

{"case":{"caseId":"case:sha256:8e5f8e8b13cdb68a34197ce81531b22a93896ba75caa26d2a032d5afc996c3f7","contract":["cast.ToDuration returns the unchanged duration when passed a time.Duration value","cast.ToDuration parses standard duration strings including seconds, minutes, and milliseconds into time.Duration","cast.ToDuration converts integer and floating-point nanosecond counts into equivalent time.Duration values","cast.ToDuration returns zero duration when conversion fails for invalid strings or unsupported types","cast.ToDurationE returns the converted duration with nil error on success, or zero duration with an error on invalid input"],"goal":"verify github.com/spf13/cast.ToDuration in pkg:golang/github.com/spf13/cast@v1.4.1","kind":"HOW","packages":["pkg:golang/github.com/spf13/cast@v1.4.1"],"schemaVersion":1,"symbols":["github.com/spf13/cast.ToDuration"]},"contractCommand":["go","run","./test"],"environment":{"arch":"x64","distro":"ubuntu","ecosystem":"golang","libc":"glibc","libcVersion":"2.39","os":"linux","osVersionBucket":"24","packageManager":"go","schemaVersion":1},"license":"MIT-0","packages":["pkg:golang/github.com/spf13/cast@v1.4.1"],"schemaVersion":1,"subject":"pkg:golang/github.com/spf13/cast@v1.4.1","symbols":["github.com/spf13/cast.ToDuration"],"verifierAdapter":"golang@1"}

module example.com/sample

go 1.22

require github.com/spf13/cast v1.4.1

github.com/davecgh/go-spew v1.1.1 h1:vj9j/u1bqnvCEfJOwUhtlOARqs3+rkHYY13jYWTU97c=
github.com/davecgh/go-spew v1.1.1/go.mod h1:J7Y8YcW2NihsgmVo/mv3lAwl/skON4iLHjSsI+c5H38=
github.com/pmezard/go-difflib v1.0.0 h1:4DBwDE0NGyQoBHbLQYPwSUPoCMWR5BEzIk/f1lZbAQM=
github.com/pmezard/go-difflib v1.0.0/go.mod h1:iKH77koFhYxTK1pcRnkKkqfTogsbg7gZNVY4sRDYZ/4=
github.com/spf13/cast v1.4.1 h1:s0hze+J0196ZfEMTs80N7UlFt0BDuQ7Q+JDnHiMWKdA=
github.com/spf13/cast v1.4.1/go.mod h1:Qx5cxh0v+4UWYiBimWS+eyWzqEqokIECu5etghLkUJE=
github.com/stretchr/testify v1.2.2 h1:bSDNvY7ZPG5RlJ8otE/7V6gMiyenm9RtJ7IUVIAoJ1w=
github.com/stretchr/testify v1.2.2/go.mod h1:a8OnRcib4nhh0OaRAV+Yts87kKdq0PP7pXfy6kDkUVs=

package main

import (
	"fmt"
	"time"

	"github.com/spf13/cast"
)

// ParseDuration converts supported types into time.Duration using cast.ToDurationE.
func ParseDuration(val any) (time.Duration, error) {
	return cast.ToDurationE(val)
}

func main() {
	inputs := []any{
		"10s",
		"2m30s",
		500 * time.Millisecond,
		int64(2000000000),
		float64(1000000),
	}

	for _, input := range inputs {
		d, err := ParseDuration(input)
		if err != nil {
			fmt.Printf("Error converting %v: %v\n", input, err)
			continue
		}
		fmt.Printf("Parsed %v -> %v\n", input, d)
	}

	raw := cast.ToDuration("45s")
	fmt.Printf("Direct ToDuration: %v\n", raw)
}

{
  "schemaVersion": 1,
  "goal": "verify github.com/spf13/cast.ToDuration in pkg:golang/github.com/spf13/cast@v1.4.1",
  "kind": "HOW",
  "packages": [
    "pkg:golang/github.com/spf13/cast@v1.4.1"
  ],
  "symbols": [
    "github.com/spf13/cast.ToDuration"
  ]
}

package main

import (
	"fmt"
	"os"
	"time"

	"github.com/spf13/cast"
)

func main() {
	// 1. cast.ToDuration returns the unchanged duration when passed a time.Duration value
	expectedDuration := 42 * time.Second
	if got := cast.ToDuration(expectedDuration); got != expectedDuration {
		fmt.Fprintf(os.Stderr, "FAIL: expected %v for time.Duration, got %v\n", expectedDuration, got)
		os.Exit(1)
	}

	// 2. cast.ToDuration parses standard duration strings including seconds, minutes, and milliseconds into time.Duration
	stringCases := []struct {
		input    string
		expected time.Duration
	}{
		{"10s", 10 * time.Second},
		{"1m30s", 90 * time.Second},
		{"500ms", 500 * time.Millisecond},
		{"2h", 2 * time.Hour},
		{"250us", 250 * time.Microsecond},
	}
	for _, tc := range stringCases {
		if got := cast.ToDuration(tc.input); got != tc.expected {
			fmt.Fprintf(os.Stderr, "FAIL: ToDuration(%q) = %v, expected %v\n", tc.input, got, tc.expected)
			os.Exit(1)
		}
	}

	// 3. cast.ToDuration converts integer and floating-point nanosecond counts into equivalent time.Duration values
	if got := cast.ToDuration(int(5000000000)); got != 5*time.Second {
		fmt.Fprintf(os.Stderr, "FAIL: int 5000000000 ns = %v, expected 5s\n", got)
		os.Exit(1)
	}
	if got := cast.ToDuration(int64(2000000000)); got != 2*time.Second {
		fmt.Fprintf(os.Stderr, "FAIL: int64 2000000000 ns = %v, expected 2s\n", got)
		os.Exit(1)
	}
	if got := cast.ToDuration(float64(3000000000)); got != 3*time.Second {
		fmt.Fprintf(os.Stderr, "FAIL: float64 3000000000 ns = %v, expected 3s\n", got)
		os.Exit(1)
	}

	// 4. cast.ToDuration returns zero duration when conversion fails for invalid strings or unsupported types
	if got := cast.ToDuration("invalid-duration-format"); got != 0 {
		fmt.Fprintf(os.Stderr, "FAIL: expected 0 for invalid string, got %v\n", got)
		os.Exit(1)
	}
	if got := cast.ToDuration([]int{1, 2, 3}); got != 0 {
		fmt.Fprintf(os.Stderr, "FAIL: expected 0 for unsupported slice, got %v\n", got)
		os.Exit(1)
	}
	if got := cast.ToDuration(nil); got != 0 {
		fmt.Fprintf(os.Stderr, "FAIL: expected 0 for nil, got %v\n", got)
		os.Exit(1)
	}

	// 5. cast.ToDurationE returns the converted duration with nil error on success, or zero duration with an error on invalid input
	val, err := cast.ToDurationE("15s")
	if err != nil || val != 15*time.Second {
		fmt.Fprintf(os.Stderr, "FAIL: ToDurationE(\"15s\") failed: got val=%v, err=%v\n", val, err)
		os.Exit(1)
	}

	failVal, failErr := cast.ToDurationE("not-a-duration")
	if failErr == nil {
		fmt.Fprintf(os.Stderr, "FAIL: expected error from ToDurationE for invalid string, got nil\n")
		os.Exit(1)
	}
	if failVal != 0 {
		fmt.Fprintf(os.Stderr, "FAIL: expected 0 value on error from ToDurationE, got %v\n", failVal)
		os.Exit(1)
	}

	fmt.Println("PASS: all cast.ToDuration contract assertions passed")
}