tinyspy 3.0.2: spies

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 tinyspy.spies in pkg:npm/tinyspy@3.0.2
Kind: HOW

Use EXACTLY these public packages and versions:
  - pkg:npm/tinyspy@3.0.2
Demonstrate these symbols/APIs:
  - tinyspy.spies

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:sha256:37099098024062e42be3d7db4b65dff1cc6c8979cf4c3868421210f877c9f5d8","constraints":{"executionContext":"node"},"contract":["spies is a Set instance tracking active spies created by spyOn","spyOn automatically registers created spy instances in spies","standalone spy is not registered in spies","spies tracks multiple spy instances across different target objects","iterating over spies yields all registered spy instances in insertion order","manual deletion from spies Set removes spy from tracking","restoreAll restores all original methods across spied objects and clears the spies Set"],"goal":"verify tinyspy.spies in pkg:npm/tinyspy@3.0.2","kind":"HOW","packages":["pkg:npm/tinyspy@3.0.2"],"schemaVersion":1,"symbols":["tinyspy.spies"]},"contractCommand":["node","test/contract.mjs"],"environment":{"arch":"x64","distro":"ubuntu","ecosystem":"npm","executionContext":"node","language":"javascript","libc":"glibc","libcVersion":"2.39","moduleSystem":"esm","os":"linux","osVersionBucket":"24","packageManager":"npm","packageManagerVersion":"10.9.8","runtime":"node","runtimeVersion":"22.23.2","schemaVersion":1},"license":"MIT-0","packages":["pkg:npm/tinyspy@3.0.2"],"schemaVersion":1,"subject":"pkg:npm/tinyspy@3.0.2","symbols":["tinyspy.spies"],"verifierAdapter":"node-typescript@1"}

{
  "name": "sample-tinyspy",
  "version": "1.0.0",
  "lockfileVersion": 3,
  "requires": true,
  "packages": {
    "": {
      "name": "sample-tinyspy",
      "version": "1.0.0",
      "license": "MIT-0",
      "dependencies": {
        "tinyspy": "3.0.2"
      }
    },
    "node_modules/tinyspy": {
      "version": "3.0.2",
      "resolved": "https://registry.npmjs.org/tinyspy/-/tinyspy-3.0.2.tgz",
      "integrity": "sha512-n1cw8k1k0x4pgA2+9XrOkFydTerNcJ1zWCO5Nn9scWHTD+5tp8dghT2x1uduQePZTZgd3Tupf+x9BxJjeJi77Q==",
      "license": "MIT",
      "engines": {
        "node": ">=14.0.0"
      }
    }
  }
}

{
  "name": "sample-tinyspy",
  "version": "1.0.0",
  "type": "module",
  "private": true,
  "description": "Clean-room verification for tinyspy.spies in tinyspy@3.0.2",
  "main": "test/contract.mjs",
  "scripts": {
    "test": "node test/contract.mjs"
  },
  "dependencies": {
    "tinyspy": "3.0.2"
  },
  "license": "MIT-0"
}

{
  "schemaVersion": 1,
  "goal": "verify tinyspy.spies in pkg:npm/tinyspy@3.0.2",
  "kind": "HOW",
  "packages": [
    "pkg:npm/tinyspy@3.0.2"
  ],
  "symbols": [
    "tinyspy.spies"
  ]
}

import assert from "node:assert";
import { spies, spyOn, restoreAll, spy } from "tinyspy";

async function runContract() {
  // Ensure spies starts empty in a clean run
  restoreAll();

  // 1. spies is an instance of Set and starts empty
  assert.ok(spies instanceof Set, "spies must be an instance of Set");
  assert.strictEqual(spies.size, 0, "spies must be empty initially");

  // 2. spy created via spyOn is automatically added to spies
  const targetA = {
    methodA(x) {
      return x * 10;
    },
  };
  const spyA = spyOn(targetA, "methodA");
  assert.strictEqual(spies.size, 1, "spies size should be 1 after spyOn");
  assert.strictEqual(spies.has(spyA), true, "spies must contain spyA");
  assert.strictEqual(targetA.methodA(5), 50, "spied method returns correct value");
  assert.strictEqual(spyA.called, true, "spyA was called");
  assert.deepStrictEqual(spyA.calls, [[5]], "spyA recorded call arguments");

  // 3. standalone spy() is not added to spies
  const standalone = spy((n) => n + 1);
  assert.strictEqual(standalone(1), 2, "standalone spy works");
  assert.strictEqual(spies.has(standalone), false, "standalone spy must not be in spies Set");
  assert.strictEqual(spies.size, 1, "spies size remains 1");

  // 4. multiple spies across different target objects are tracked
  const targetB = {
    methodB(s) {
      return `hello ${s}`;
    },
    methodC() {
      return 42;
    },
  };
  const spyB = spyOn(targetB, "methodB");
  const spyC = spyOn(targetB, "methodC");
  assert.strictEqual(spies.size, 3, "spies size should be 3 after adding two more spies");
  assert.strictEqual(spies.has(spyB), true, "spies must contain spyB");
  assert.strictEqual(spies.has(spyC), true, "spies must contain spyC");

  // 5. iterating over spies yields all registered spy instances
  const trackedSpies = Array.from(spies);
  assert.deepStrictEqual(
    trackedSpies,
    [spyA, spyB, spyC],
    "iterating spies yields the exact spy instances in insertion order"
  );

  // 6. manual deletion from spies Set
  spies.delete(spyA);
  assert.strictEqual(spies.size, 2, "spies size should decrement after manual delete");
  assert.strictEqual(spies.has(spyA), false, "spies should no longer contain spyA");
  spyA.restore();
  assert.strictEqual(targetA.methodA(5), 50, "targetA.methodA still works after restore");

  // 7. restoreAll restores all remaining spies and clears the spies Set
  targetB.methodB("world");
  assert.strictEqual(spyB.called, true, "spyB was called");
  restoreAll();
  assert.strictEqual(spies.size, 0, "spies must be empty after restoreAll");
  assert.strictEqual(spies.has(spyB), false, "spyB removed from spies");
  assert.strictEqual(spies.has(spyC), false, "spyC removed from spies");
  assert.notStrictEqual(targetB.methodB, spyB, "targetB.methodB restored to original method");
  assert.notStrictEqual(targetB.methodC, spyC, "targetB.methodC restored to original method");
  assert.strictEqual(targetB.methodB("code"), "hello code", "original methodB functions correctly");
  assert.strictEqual(targetB.methodC(), 42, "original methodC functions correctly");

  console.log("All contract assertions passed successfully.");
}

runContract().catch((err) => {
  console.error("Contract test failed:", err);
  process.exit(1);
});