github.com/stretchr/testify v1.7.0: require

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 require in pkg:golang/github.com/stretchr/testify@v1.7.0
Kind: HOW

Use EXACTLY these public packages and versions:
  - pkg:golang/github.com/stretchr/testify@v1.7.0
Demonstrate these symbols/APIs:
  - require

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:sha256:22e6afc0e8e9a68c509e214c6a4fa9584b2cd4040770488979004d72ec7183e8","contract":["require.Equal and require.NotEqual succeed without calling Errorf or FailNow when comparison conditions are met","require.Equal records an error and invokes FailNow when compared values do not match","require.NoError succeeds for nil error and triggers Errorf and FailNow when error is non-nil","require.Len validates collection lengths and calls FailNow on count mismatch","require.New binds a TestingT instance and executes assertions with FailNow failure semantics"],"goal":"verify require in pkg:golang/github.com/stretchr/testify@v1.7.0","kind":"HOW","packages":["pkg:golang/github.com/stretchr/testify@v1.7.0"],"schemaVersion":1,"symbols":["require"]},"contractCommand":["go","run","./test"],"environment":{"arch":"x64","distro":"ubuntu","ecosystem":"golang","language":"go","libc":"glibc","libcVersion":"2.39","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/stretchr/testify@v1.7.0"],"schemaVersion":1,"subject":"pkg:golang/github.com/stretchr/testify@v1.7.0","symbols":["require"],"verifierAdapter":"golang@1"}

module sample

go 1.26.6

require github.com/stretchr/testify v1.7.0

require (
	github.com/davecgh/go-spew v1.1.0 // indirect
	github.com/pmezard/go-difflib v1.0.0 // indirect
	gopkg.in/yaml.v3 v3.0.0-20200313102051-9f266ea9e77c // indirect
)

github.com/davecgh/go-spew v1.1.0 h1:ZDRjVQ15GmhC3fiQ8ni8+OwkZQO4DARzQgrnXU1Liz8=
github.com/davecgh/go-spew v1.1.0/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/stretchr/objx v0.1.0/go.mod h1:HFkY916IF+rwdDfMAkV7OtwuqBVzrE8GR6GFx+wExME=
github.com/stretchr/testify v1.7.0 h1:nwc3DEeHmmLAfoZucVR881uASk0Mfjw8xYJ99tb5CcY=
github.com/stretchr/testify v1.7.0/go.mod h1:6Fq8oRcR53rry900zMqJjRRixrwX3KX962/h/Wwjteg=
gopkg.in/check.v1 v0.0.0-20161208181325-20d25e280405 h1:yhCVgyC4o1eVCa2tZl7eS0r+SDo693bJlVdllGtEeKM=
gopkg.in/check.v1 v0.0.0-20161208181325-20d25e280405/go.mod h1:Co6ibVJAznAaIkqp8huTwlJQCZ016jof/cbN4VW5Yz0=
gopkg.in/yaml.v3 v3.0.0-20200313102051-9f266ea9e77c h1:dUUwHk2QECo/6vqA44rthZ8ie2QXMNeKRTHCNY2nXvo=
gopkg.in/yaml.v3 v3.0.0-20200313102051-9f266ea9e77c/go.mod h1:K4uyk7z7BCEPqu6E+C64Yfv1cQ7kz7rIZviUmN+EgEM=

package main

import (
	"fmt"
	"os"

	"github.com/stretchr/testify/require"
)

// reporter implements require.TestingT to record assertion events.
type reporter struct {
	hasFailed bool
	messages  []string
}

func (r *reporter) Errorf(format string, args ...interface{}) {
	r.hasFailed = true
	r.messages = append(r.messages, fmt.Sprintf(format, args...))
}

func (r *reporter) FailNow() {
	r.hasFailed = true
}

func main() {
	rep := &reporter{}

	// Direct assertion functions
	require.Equal(rep, 42, 42)
	require.NotEqual(rep, "alpha", "beta")

	var err error
	require.NoError(rep, err)

	items := []string{"first", "second", "third"}
	require.Len(rep, items, 3)

	// Bound assertions instance via require.New
	req := require.New(rep)
	req.True(len(items) > 0)
	req.Contains(items, "second")

	if !rep.hasFailed {
		fmt.Println("All require demonstrations passed successfully.")
	} else {
		fmt.Fprintf(os.Stderr, "Unexpected failure in require demonstration.\n")
		os.Exit(1)
	}
}

{
  "schemaVersion": 1,
  "goal": "verify require in pkg:golang/github.com/stretchr/testify@v1.7.0",
  "kind": "HOW",
  "packages": [
    "pkg:golang/github.com/stretchr/testify@v1.7.0"
  ],
  "symbols": [
    "require"
  ]
}

package main

import (
	"errors"
	"fmt"
	"os"

	"github.com/stretchr/testify/require"
)

type contractTestingT struct {
	errors        []string
	failed        bool
	failNowCalled bool
}

func (t *contractTestingT) Errorf(format string, args ...interface{}) {
	t.failed = true
	t.errors = append(t.errors, fmt.Sprintf(format, args...))
}

func (t *contractTestingT) FailNow() {
	t.failNowCalled = true
}

func main() {
	// Assertion 1: require.Equal and require.NotEqual succeed without calling Errorf or FailNow when comparison conditions are met
	{
		t := &contractTestingT{}
		require.Equal(t, 100, 100)
		require.NotEqual(t, "apple", "orange")
		if t.failed || t.failNowCalled || len(t.errors) != 0 {
			fmt.Fprintf(os.Stderr, "assertion 1 failed: require.Equal and require.NotEqual should succeed without errors\n")
			os.Exit(1)
		}
	}

	// Assertion 2: require.Equal records an error and invokes FailNow when compared values do not match
	{
		t := &contractTestingT{}
		require.Equal(t, "expected", "actual")
		if !t.failed || !t.failNowCalled || len(t.errors) == 0 {
			fmt.Fprintf(os.Stderr, "assertion 2 failed: require.Equal should record error and call FailNow on mismatch\n")
			os.Exit(1)
		}
	}

	// Assertion 3: require.NoError succeeds for nil error and triggers Errorf and FailNow when error is non-nil
	{
		tNil := &contractTestingT{}
		require.NoError(tNil, nil)
		if tNil.failed || tNil.failNowCalled || len(tNil.errors) != 0 {
			fmt.Fprintf(os.Stderr, "assertion 3 failed: require.NoError should succeed for nil error\n")
			os.Exit(1)
		}

		tErr := &contractTestingT{}
		require.NoError(tErr, errors.New("synthetic error"))
		if !tErr.failed || !tErr.failNowCalled || len(tErr.errors) == 0 {
			fmt.Fprintf(os.Stderr, "assertion 3 failed: require.NoError should trigger error and FailNow for non-nil error\n")
			os.Exit(1)
		}
	}

	// Assertion 4: require.Len validates collection lengths and calls FailNow on count mismatch
	{
		tLenPass := &contractTestingT{}
		sliceVal := []int{1, 2, 3}
		require.Len(tLenPass, sliceVal, 3)
		if tLenPass.failed || tLenPass.failNowCalled || len(tLenPass.errors) != 0 {
			fmt.Fprintf(os.Stderr, "assertion 4 failed: require.Len should pass on matching length\n")
			os.Exit(1)
		}

		tLenFail := &contractTestingT{}
		require.Len(tLenFail, sliceVal, 5)
		if !tLenFail.failed || !tLenFail.failNowCalled || len(tLenFail.errors) == 0 {
			fmt.Fprintf(os.Stderr, "assertion 4 failed: require.Len should trigger FailNow on length mismatch\n")
			os.Exit(1)
		}
	}

	// Assertion 5: require.New binds a TestingT instance and executes assertions with FailNow failure semantics
	{
		tPass := &contractTestingT{}
		reqPass := require.New(tPass)
		reqPass.True(true)
		reqPass.Contains([]string{"x", "y"}, "y")
		if tPass.failed || tPass.failNowCalled || len(tPass.errors) != 0 {
			fmt.Fprintf(os.Stderr, "assertion 5 failed: require.New assertions should pass when condition holds\n")
			os.Exit(1)
		}

		tFail := &contractTestingT{}
		reqFail := require.New(tFail)
		reqFail.True(false)
		if !tFail.failed || !tFail.failNowCalled || len(tFail.errors) == 0 {
			fmt.Fprintf(os.Stderr, "assertion 5 failed: require.New assertions should invoke FailNow on failure\n")
			os.Exit(1)
		}
	}

	fmt.Println("All contract assertions passed successfully.")
}