github.com/jackc/pgio v1.0.0

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/jackc/pgio@v1.0.0
Kind: HOW

Use EXACTLY these public packages and versions:
  - pkg:golang/github.com/jackc/pgio@v1.0.0
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:sha256:3a4ac3a123eff2e76ae291c0e6bcd7bdbdebc4013638335fa9205354ed9de338","contract":["pgio.AppendInt16 appends big-endian int16 to buffer","pgio.AppendInt32 appends big-endian int32 to buffer","pgio.AppendInt64 appends big-endian int64 to buffer","pgio.AppendUint16 appends big-endian uint16 to buffer","pgio.AppendUint32 appends big-endian uint32 to buffer","pgio.AppendUint64 appends big-endian uint64 to buffer","pgio.SetInt32 writes big-endian int32 into existing buffer slice"],"goal":"verify pkg:golang/github.com/jackc/pgio@v1.0.0","kind":"HOW","packages":["pkg:golang/github.com/jackc/pgio@v1.0.0"],"schemaVersion":1},"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/jackc/pgio@v1.0.0"],"schemaVersion":1,"subject":"pkg:golang/github.com/jackc/pgio@v1.0.0","verifierAdapter":"golang@1"}

module example.com/sample

go 1.22

require github.com/jackc/pgio v1.0.0

github.com/jackc/pgio v1.0.0 h1:g12B9UwVnzGhueNavwioyEEpAmqMe1E/BN9ES+8ovkE=
github.com/jackc/pgio v1.0.0/go.mod h1:oP+2QK2wFfUWgr+gxjoBH9KGBb31Eio69xUb0w5bYf8=

package main

import (
	"fmt"

	"github.com/jackc/pgio"
)

func main() {
	buf := make([]byte, 0, 16)
	buf = pgio.AppendInt16(buf, 100)
	buf = pgio.AppendInt32(buf, 200000)
	buf = pgio.AppendInt64(buf, 3000000000)
	fmt.Printf("Buffer length: %d, bytes: %v\n", len(buf), buf)
}

{
  "schemaVersion": 1,
  "goal": "verify pkg:golang/github.com/jackc/pgio@v1.0.0",
  "kind": "HOW",
  "packages": [
    "pkg:golang/github.com/jackc/pgio@v1.0.0"
  ],
  "constraints": {
    "executionContext": "node"
  },
  "runtimeConditions": {
    "ecosystem": "npm",
    "language": "javascript",
    "moduleSystem": "cjs",
    "packageManager": "npm@10.9.8",
    "runtime": "node@22.23.2"
  }
}

package main

import (
	"bytes"
	"fmt"
	"os"

	"github.com/jackc/pgio"
)

func main() {
	// 1. pgio.AppendInt16 appends big-endian int16 to buffer
	buf := pgio.AppendInt16(nil, 0x1234)
	if !bytes.Equal(buf, []byte{0x12, 0x34}) {
		fmt.Fprintf(os.Stderr, "AppendInt16 failed: got %v, want %v\n", buf, []byte{0x12, 0x34})
		os.Exit(1)
	}

	// 2. pgio.AppendInt32 appends big-endian int32 to buffer
	buf = pgio.AppendInt32(nil, 0x12345678)
	if !bytes.Equal(buf, []byte{0x12, 0x34, 0x56, 0x78}) {
		fmt.Fprintf(os.Stderr, "AppendInt32 failed: got %v, want %v\n", buf, []byte{0x12, 0x34, 0x56, 0x78})
		os.Exit(1)
	}

	// 3. pgio.AppendInt64 appends big-endian int64 to buffer
	buf = pgio.AppendInt64(nil, 0x123456789abcdef0)
	if !bytes.Equal(buf, []byte{0x12, 0x34, 0x56, 0x78, 0x9a, 0xbc, 0xde, 0xf0}) {
		fmt.Fprintf(os.Stderr, "AppendInt64 failed: got %v, want %v\n", buf, []byte{0x12, 0x34, 0x56, 0x78, 0x9a, 0xbc, 0xde, 0xf0})
		os.Exit(1)
	}

	// 4. pgio.AppendUint16 appends big-endian uint16 to buffer
	buf = pgio.AppendUint16(nil, 0xabcd)
	if !bytes.Equal(buf, []byte{0xab, 0xcd}) {
		fmt.Fprintf(os.Stderr, "AppendUint16 failed: got %v, want %v\n", buf, []byte{0xab, 0xcd})
		os.Exit(1)
	}

	// 5. pgio.AppendUint32 appends big-endian uint32 to buffer
	buf = pgio.AppendUint32(nil, 0xdeadbeef)
	if !bytes.Equal(buf, []byte{0xde, 0xad, 0xbe, 0xef}) {
		fmt.Fprintf(os.Stderr, "AppendUint32 failed: got %v, want %v\n", buf, []byte{0xde, 0xad, 0xbe, 0xef})
		os.Exit(1)
	}

	// 6. pgio.AppendUint64 appends big-endian uint64 to buffer
	buf = pgio.AppendUint64(nil, 0x0123456789abcdef)
	if !bytes.Equal(buf, []byte{0x01, 0x23, 0x45, 0x67, 0x89, 0xab, 0xcd, 0xef}) {
		fmt.Fprintf(os.Stderr, "AppendUint64 failed: got %v, want %v\n", buf, []byte{0x01, 0x23, 0x45, 0x67, 0x89, 0xab, 0xcd, 0xef})
		os.Exit(1)
	}

	// 7. pgio.SetInt32 writes big-endian int32 into existing buffer slice
	dest := make([]byte, 4)
	pgio.SetInt32(dest, 0x01020304)
	if !bytes.Equal(dest, []byte{0x01, 0x02, 0x03, 0x04}) {
		fmt.Fprintf(os.Stderr, "SetInt32 failed: got %v, want %v\n", dest, []byte{0x01, 0x02, 0x03, 0x04})
		os.Exit(1)
	}

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