github.com/subosito/gotenv v1.6.0

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 pkg:golang/github.com/subosito/gotenv@v1.6.0
Kind: HOW

Use EXACTLY these public packages and versions:
  - pkg:golang/github.com/subosito/gotenv@v1.6.0
Required runtime conditions:
  - ecosystem: golang
  - language: go
  - packageManager: go@1.26.6
  - runtime: go@1.26.6

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:sha256:790205d2cc556860a361e80842217ce50d05b0cfccc32e3ae8f284bd92ed0360","contract":["gotenv.Parse parses key-value pairs from an io.Reader","gotenv.Parse ignores comments and blank lines","gotenv.StrictParse returns an error for malformed lines","gotenv.Apply sets unset environment variables without overwriting existing ones","gotenv.OverApply overwrites existing environment variables from an io.Reader"],"goal":"verify pkg:golang/github.com/subosito/gotenv@v1.6.0","kind":"HOW","packages":["pkg:golang/github.com/subosito/gotenv@v1.6.0"],"schemaVersion":1},"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/subosito/gotenv@v1.6.0"],"schemaVersion":1,"subject":"pkg:golang/github.com/subosito/gotenv@v1.6.0","verifierAdapter":"golang@1"}

module example.com/sample

go 1.26.6

require github.com/subosito/gotenv v1.6.0

require golang.org/x/text v0.12.0 // indirect

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/stretchr/testify v1.7.5 h1:s5PTfem8p8EbKQOctVV53k6jCJt3UX4IEJzwh+C324Q=
github.com/stretchr/testify v1.7.5/go.mod h1:yNjHg4UonilssWZ8iaSj1OCr/vHnekPRkoO+kdMU+MU=
github.com/subosito/gotenv v1.6.0 h1:9NlTDc1FTs4qu0DDq7AEtTPNw6SVm7uBMsUCUjABIf8=
github.com/subosito/gotenv v1.6.0/go.mod h1:Dk4QP5c2W3ibzajGcXpNraDfq2IrhjMIvMSWPKKo0FU=
golang.org/x/text v0.12.0 h1:k+n5B8goJNdU7hSvEtMUz3d1Q6D/XW4COJSJR6fN0mc=
golang.org/x/text v0.12.0/go.mod h1:TvPlkZtksWOMsz7fbANvkp4WM8x/WCo/om8BMLbz+aE=
gopkg.in/yaml.v3 v3.0.1 h1:fxVm/GzAzEWqLHuvctI91KS9hhNmmWOoWu0XTYJS7CA=
gopkg.in/yaml.v3 v3.0.1/go.mod h1:K4uyk7z7BCEPqu6E+C64Yfv1cQ7kz7rIZviUmN+EgEM=

package main

import (
	"fmt"
	"strings"

	"github.com/subosito/gotenv"
)

// ParseConfig parses environment variables from a string.
func ParseConfig(raw string) gotenv.Env {
	reader := strings.NewReader(raw)
	return gotenv.Parse(reader)
}

func main() {
	sampleEnv := "APP_ENV=production\nPORT=8080\n"
	env := ParseConfig(sampleEnv)
	fmt.Printf("Loaded %d variables: APP_ENV=%s, PORT=%s\n", len(env), env["APP_ENV"], env["PORT"])
}

{
  "schemaVersion": 1,
  "goal": "verify pkg:golang/github.com/subosito/gotenv@v1.6.0",
  "kind": "HOW",
  "packages": [
    "pkg:golang/github.com/subosito/gotenv@v1.6.0"
  ],
  "runtimeConditions": {
    "ecosystem": "golang",
    "language": "go",
    "packageManager": "go@1.26.6",
    "runtime": "go@1.26.6"
  }
}

package main

import (
	"fmt"
	"os"
	"strings"

	"github.com/subosito/gotenv"
)

func assert(condition bool, message string) {
	if !condition {
		panic(fmt.Sprintf("assertion failed: %s", message))
	}
}

func main() {
	// 1. gotenv.Parse parses key-value pairs from an io.Reader
	{
		input := "KEY1=value1\nKEY2=value2\n"
		env := gotenv.Parse(strings.NewReader(input))
		assert(env["KEY1"] == "value1", "KEY1 must be value1")
		assert(env["KEY2"] == "value2", "KEY2 must be value2")
	}

	// 2. gotenv.Parse ignores comments and blank lines
	{
		input := "# Leading comment\n\nNAME=gotenv\n  # Indented comment\n\nVERSION=1.6.0\n"
		env := gotenv.Parse(strings.NewReader(input))
		assert(len(env) == 2, "env should contain exactly 2 parsed entries")
		assert(env["NAME"] == "gotenv", "NAME must be gotenv")
		assert(env["VERSION"] == "1.6.0", "VERSION must be 1.6.0")
	}

	// 3. gotenv.StrictParse returns an error for malformed lines
	{
		input := "VALID=1\nTHIS_LINE_HAS_NO_DELIMITER\n"
		_, err := gotenv.StrictParse(strings.NewReader(input))
		assert(err != nil, "gotenv.StrictParse must return error for malformed line")
	}

	// 4. gotenv.Apply sets unset environment variables without overwriting existing ones
	{
		testKeyExisting := "TEST_CSX_EXISTING"
		testKeyNew := "TEST_CSX_NEW"
		os.Setenv(testKeyExisting, "original_val")
		defer os.Unsetenv(testKeyExisting)
		defer os.Unsetenv(testKeyNew)

		input := fmt.Sprintf("%s=new_val\n%s=created_val\n", testKeyExisting, testKeyNew)
		err := gotenv.Apply(strings.NewReader(input))
		assert(err == nil, "gotenv.Apply should succeed")
		assert(os.Getenv(testKeyExisting) == "original_val", "Apply must not overwrite existing variable")
		assert(os.Getenv(testKeyNew) == "created_val", "Apply must set unset variable")
	}

	// 5. gotenv.OverApply overwrites existing environment variables from an io.Reader
	{
		testKey := "TEST_CSX_OVERWRITE"
		os.Setenv(testKey, "before_overwrite")
		defer os.Unsetenv(testKey)

		input := fmt.Sprintf("%s=after_overwrite\n", testKey)
		err := gotenv.OverApply(strings.NewReader(input))
		assert(err == nil, "gotenv.OverApply should succeed")
		assert(os.Getenv(testKey) == "after_overwrite", "OverApply must overwrite existing variable")
	}

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