commander 15.0.0: Prove that Commander treats a paired positive and negated boolean flag set as undefined by default.

The prior-scan returned reference-only results for this library, including sample `sha256:e9734b35dd9bf261570327aa6767cba61b29225dbb1b6eebc59d47cb344f1141` proving paired `--cache` / `--no-cache` boolean flags are `undefined` when omitted in Commander 15, while `Option.implies("--foo")` was a separate existing trap.

On older Commander lines, the same script can fail as a green build (false belief): both flags omitted are treated as `true` with implicit `default`, which does not match Commander 15’s paired-flag behavior.

{"case":{"believed":"When both `--cache` and `--no-cache` are defined, omitting both options should leave `cache` as `true` because the negated form implies a true default.","caseId":"case:sha256:9ed18ee2a8f497a0a85a0cf29e27989636082f10fb3e855a3228d05cd0c52c3b","contract":["With both `--cache` and `--no-cache`, parsing without either flag leaves `program.opts().cache` as `undefined`, even though the negated option alone would default to true.","Without flags, `program.getOptionValueSource('cache')` is `undefined`, not `default`.","Parsing `--cache` sets `program.opts().cache` to `true` and `program.getOptionValueSource('cache')` to `cli`.","Parsing `--no-cache` sets `program.opts().cache` to `false` and `program.getOptionValueSource('cache')` to `cli`."],"goal":"Prove that Commander treats a paired positive and negated boolean flag set as undefined by default.","kind":"HOW","packages":["pkg:npm/commander@15.0.0"],"schemaVersion":1,"symbols":["Command","Command.getOptionValueSource","Command.opts"]},"contractCommand":["node","test/contract.mjs"],"environment":{"arch":"x64","ecosystem":"npm","executionContext":"node","language":"node","os":"linux","packageManager":"npm","runtime":"node","schemaVersion":1},"license":"MIT-0","packages":["pkg:npm/commander@15.0.0"],"schemaVersion":1,"symbols":["Command","Command.getOptionValueSource","Command.opts"],"verifierAdapter":"node-typescript@1"}

{
  "name": "npm-commander-d4",
  "version": "1.0.0",
  "lockfileVersion": 3,
  "requires": true,
  "packages": {
    "": {
      "name": "npm-commander-d4",
      "version": "1.0.0",
      "license": "MIT-0",
      "dependencies": {
        "commander": "15.0.0"
      }
    },
    "node_modules/commander": {
      "version": "15.0.0",
      "resolved": "https://registry.npmjs.org/commander/-/commander-15.0.0.tgz",
      "integrity": "sha512-z67u4ZhzCL/Tydu1lJARtEZYWbWaN7oYLHbsuzocr6y4N6WZAagG3RQ4FW61V1/0+jImpj293XfrcYnd1qxtPg==",
      "license": "MIT",
      "engines": {
        "node": ">=22.12.0"
      }
    }
  }
}

{
  "name": "npm-commander-d4",
  "version": "1.0.0",
  "private": true,
  "type": "module",
  "license": "MIT-0",
  "scripts": {
    "test": "node test/contract.mjs"
  },
  "dependencies": {
    "commander": "15.0.0"
  }
}

import assert from "node:assert/strict";
import { Command } from "commander";

function makeProgram() {
  return new Command()
    .option("--cache", "Enable cache")
    .option("--no-cache", "Disable cache");
}

function assertCacheState(argv, expectedValue, expectedSource) {
  const program = makeProgram();
  program.parse(argv, { from: "node" });
  assert.equal(program.opts().cache, expectedValue);
  assert.equal(program.getOptionValueSource("cache"), expectedSource);
}

assertCacheState(["node", "app"], undefined, undefined);
assertCacheState(["node", "app", "--cache"], true, "cli");
assertCacheState(["node", "app", "--no-cache"], false, "cli");