github.com/stretchr/testify v1.3.0: assert.True

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/stretchr/testify/assert.True in pkg:golang/github.com/stretchr/testify@v1.3.0
Kind: HOW

Use EXACTLY these public packages and versions:
  - pkg:golang/github.com/stretchr/testify@v1.3.0
Demonstrate these symbols/APIs:
  - github.com/stretchr/testify/assert.True
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.

{"case":{"caseId":"case:sha256:37cc55e5229d0811dfd0fbe333c6d73282fc84935c7abbbb2166a834d70e2231","contract":["assert.True returns true and does not record an error when the value is true","assert.True returns false and records an error when the value is false","assert.True includes formatted custom failure messages when an assertion on false fails","assert.True preserves success without recording errors when optional message arguments are provided for a true value"],"goal":"verify github.com/stretchr/testify/assert.True in pkg:golang/github.com/stretchr/testify@v1.3.0","kind":"HOW","packages":["pkg:golang/github.com/stretchr/testify@v1.3.0"],"schemaVersion":1,"symbols":["github.com/stretchr/testify/assert.True"]},"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@v1.3.0"],"schemaVersion":1,"subject":"pkg:golang/github.com/stretchr/testify@v1.3.0","symbols":["github.com/stretchr/testify/assert.True"],"verifierAdapter":"golang@1"}

module sample

go 1.26.6

require github.com/stretchr/testify v1.3.0

require (
	github.com/davecgh/go-spew v1.1.0 // indirect
	github.com/pmezard/go-difflib v1.0.0 // 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 v1.3.0 h1:TivCn/peBQ7UY8ooIcPgZFpTNSz0Q2U6UrFlUfqbe0Q=
github.com/stretchr/testify v1.3.0/go.mod h1:M5WIy9Dh21IEIfnGCwXGc5bZfKNJtfHm1UVUgZn+9EI=

package main

import (
	"fmt"

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

// Reporter implements assert.TestingT to record assertion errors.
type Reporter struct {
	errors []string
	failed bool
}

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

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

	// Basic assertion that an expression evaluates to true
	condition := 42 > 0
	if assert.True(reporter, condition, "expected positive value") {
		fmt.Println("Condition evaluated to true.")
	}

	// Assertion with custom message formatting
	statusOK := true
	if assert.True(reporter, statusOK, "status code should be %s", "active") {
		fmt.Println("Status check passed.")
	}

	if !reporter.failed {
		fmt.Println("All assertions succeeded.")
	}
}

{
  "schemaVersion": 1,
  "goal": "verify github.com/stretchr/testify/assert.True in pkg:golang/github.com/stretchr/testify@v1.3.0",
  "kind": "HOW",
  "packages": [
    "pkg:golang/github.com/stretchr/testify@v1.3.0"
  ],
  "symbols": [
    "github.com/stretchr/testify/assert.True"
  ]
}

package main

import (
	"fmt"
	"os"
	"strings"

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

type contractTestingT struct {
	errors []string
	failed bool
}

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

func main() {
	// Assertion 1: assert.True returns true and does not record an error when the value is true
	{
		t := &contractTestingT{}
		if !assert.True(t, true) || t.failed || len(t.errors) != 0 {
			fmt.Fprintf(os.Stderr, "assertion 1 failed: assert.True should succeed on true value\n")
			os.Exit(1)
		}
	}

	// Assertion 2: assert.True returns false and records an error when the value is false
	{
		t := &contractTestingT{}
		if assert.True(t, false) || !t.failed || len(t.errors) == 0 {
			fmt.Fprintf(os.Stderr, "assertion 2 failed: assert.True should fail on false value\n")
			os.Exit(1)
		}
	}

	// Assertion 3: assert.True includes formatted custom failure messages when an assertion on false fails
	{
		t := &contractTestingT{}
		customMsg := "custom error message"
		if assert.True(t, false, "details: %s (%d)", customMsg, 123) || !t.failed || len(t.errors) == 0 {
			fmt.Fprintf(os.Stderr, "assertion 3 failed: assert.True should return false on false with custom message\n")
			os.Exit(1)
		}
		found := false
		for _, errStr := range t.errors {
			if strings.Contains(errStr, customMsg) && strings.Contains(errStr, "123") {
				found = true
				break
			}
		}
		if !found {
			fmt.Fprintf(os.Stderr, "assertion 3 failed: error output did not contain formatted custom message\n")
			os.Exit(1)
		}
	}

	// Assertion 4: assert.True preserves success without recording errors when optional message arguments are provided for a true value
	{
		t := &contractTestingT{}
		if !assert.True(t, true, "unexpected failure for %s", "ok") || t.failed || len(t.errors) != 0 {
			fmt.Fprintf(os.Stderr, "assertion 4 failed: assert.True should succeed on true value with message args\n")
			os.Exit(1)
		}
	}

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