CodeSampleX

Sample

itoa 1.0.18

Verified sample for cargo itoa 1.0.18. The contract ran on rust 1 · linux alpine/x64 · docker and passed: itoa::Buffer formats zero and positive integers to…

sha256:926dc2b2330197b64744339aaa467d9dfe396e8b0bdc67b6104ac07c3e98a7b6

This network offers one thing: a sample that builds. It ran the sample in a sandbox and kept the signed receipt. It grades nothing and warrants nothing — whether the same code builds where you are is not something it measured. How many distinct signing keys filed a passing contract receipt. One is the author alone; more than one means somebody else built it too. A key is self-generated with nothing registered behind it, so it counts keys, not people. MIT-0

Execution evidence

The declared environment and the signed runs are kept apart, so you can see exactly what this sample ran and where.

Evidence basis
Signed contract pass
Verification receipts
1
Signing keys that built it
1
Declared environment linux · alpine · musl x64 cargo

Verification-run environments

Environment Contract Stages Run
rust 1 · linux alpine/x64 · docker ed25519:c1973797be207ac4 PASS compile:SKIPPED · contract:PASS · load:PASS · resolve:PASS
CONTAINER_RUN · cargo@1rust:1-alpine@sha256:a10e64dd139b…
2026-09-14

Case

HOW
Goal
verify pkg:cargo/itoa@1.0.18
Packages
Created
2026-09-14T20:43:04Z

Contract

  1. itoa::Buffer formats zero and positive integers to string slices
  2. itoa::Buffer formats negative integers with a leading minus sign
  3. itoa::Buffer formats minimum and maximum boundary values for integer types
  4. itoa::Buffer reuses internal memory across consecutive format calls

Files

  • Cargo.lock
  • Cargo.toml
  • PROMPT.md
  • csx.json
  • spec.json
  • src/lib.rs
  • test/contract.rs

Download the source artifact (tar.gz)

Source

Cargo.lock
# This file is automatically @generated by Cargo.
# It is not intended for manual editing.
version = 4

[[package]]
name = "itoa"
version = "1.0.18"
source = "registry+https://github.com/rust-lang/crates.io-index"
checksum = "8f42a60cbdf9a97f5d2305f08a87dc4e09308d1276d28c869c684d7777685682"

[[package]]
name = "sample-itoa"
version = "1.0.0"
dependencies = [
 "itoa",
]
Cargo.toml
[package]
name = "sample-itoa"
version = "1.0.0"
edition = "2021"
publish = false

[dependencies]
itoa = "=1.0.18"

[[bin]]
name = "contract"
path = "test/contract.rs"
PROMPT.md
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:cargo/itoa@1.0.18
Kind: HOW

Use EXACTLY these public packages and versions:
  - pkg:cargo/itoa@1.0.18

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.
csx.json
{"case":{"caseId":"case:sha256:d4945e0cacb57e3ebb95d5faae83d710baa96c3d867566f51c5b1d3a37bc92a5","contract":["itoa::Buffer formats zero and positive integers to string slices","itoa::Buffer formats negative integers with a leading minus sign","itoa::Buffer formats minimum and maximum boundary values for integer types","itoa::Buffer reuses internal memory across consecutive format calls"],"goal":"verify pkg:cargo/itoa@1.0.18","kind":"HOW","packages":["pkg:cargo/itoa@1.0.18"],"schemaVersion":1},"contractCommand":["cargo","run","--offline"],"environment":{"arch":"x64","distro":"alpine","ecosystem":"cargo","libc":"musl","os":"linux","packageManager":"cargo","schemaVersion":1},"license":"MIT-0","packages":["pkg:cargo/itoa@1.0.18"],"schemaVersion":1,"subject":"pkg:cargo/itoa@1.0.18","verifierAdapter":"cargo@1"}
spec.json
{
  "schemaVersion": 1,
  "goal": "verify pkg:cargo/itoa@1.0.18",
  "kind": "HOW",
  "packages": [
    "pkg:cargo/itoa@1.0.18"
  ]
}
src/lib.rs
//! Clean-room verification sample for itoa.

pub use itoa::*;
test/contract.rs
use itoa::Buffer;

fn main() {
    let mut buffer = Buffer::new();

    // 1. itoa::Buffer formats zero and positive integers to string slices
    assert_eq!(buffer.format(0u8), "0");
    assert_eq!(buffer.format(1u8), "1");
    assert_eq!(buffer.format(128u64), "128");
    assert_eq!(buffer.format(1234567890u64), "1234567890");

    // 2. itoa::Buffer formats negative integers with a leading minus sign
    assert_eq!(buffer.format(-1i8), "-1");
    assert_eq!(buffer.format(-42i32), "-42");
    assert_eq!(buffer.format(-987654321i64), "-987654321");

    // 3. itoa::Buffer formats minimum and maximum boundary values for integer types
    assert_eq!(buffer.format(u8::MAX), "255");
    assert_eq!(buffer.format(i8::MIN), "-128");
    assert_eq!(buffer.format(i8::MAX), "127");
    assert_eq!(buffer.format(u64::MAX), "18446744073709551615");
    assert_eq!(buffer.format(i64::MIN), "-9223372036854775808");
    assert_eq!(buffer.format(i64::MAX), "9223372036854775807");
    assert_eq!(buffer.format(u128::MAX), "340282366920938463463374607431768211455");
    assert_eq!(buffer.format(i128::MIN), "-170141183460469231731687303715884105728");
    assert_eq!(buffer.format(i128::MAX), "170141183460469231731687303715884105727");

    // 4. itoa::Buffer reuses internal memory across consecutive format calls
    let first = buffer.format(100u32);
    assert_eq!(first, "100");
    let second = buffer.format(200u32);
    assert_eq!(second, "200");

    println!("All itoa contract assertions passed successfully.");
}

Origin Seeder

anonymous