@vue/shared 3.5.41: looseEqual, normalizeClass, normalizeStyle

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 normalizeClass, normalizeStyle, and looseEqual in pkg:npm/%40vue/shared@3.5.41
Kind: HOW

Use EXACTLY these public packages and versions:
  - pkg:npm/%40vue/shared@3.5.41
Demonstrate these symbols/APIs:
  - looseEqual
  - normalizeClass
  - normalizeStyle

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:c65fe754abaab836da3f15d1687e27c4317b07c63d87987076a02866e7012979","contract":["normalizeClass flattens strings, string arrays, and object truthy boolean keys into space-separated class names","normalizeClass recursively normalizes nested array and object structures and ignores falsy values","parseStringStyle converts css text into key-value style map and stringifyStyle serializes style objects","normalizeStyle preserves string styles, passes object styles, and merges array of styles","looseEqual performs deep structural equality comparison across primitives, dates, regexes, arrays, and objects","looseIndexOf finds element index in array using looseEqual semantics"],"goal":"verify normalizeClass, normalizeStyle, and looseEqual in pkg:npm/%40vue/shared@3.5.41","kind":"HOW","packages":["pkg:npm/%40vue/shared@3.5.41"],"schemaVersion":1,"symbols":["looseEqual","normalizeClass","normalizeStyle"]},"contractCommand":["node","test/contract.mjs"],"environment":{"arch":"x64","distro":"ubuntu","ecosystem":"npm","libc":"glibc","libcVersion":"2.39","os":"linux","osVersionBucket":"24","packageManager":"npm","schemaVersion":1},"license":"MIT-0","packages":["pkg:npm/%40vue/shared@3.5.41"],"schemaVersion":1,"subject":"pkg:npm/%40vue/shared@3.5.41","symbols":["looseEqual","normalizeClass","normalizeStyle"],"verifierAdapter":"node-typescript@1"}

{
  "name": "sample-vue-shared",
  "version": "1.0.0",
  "lockfileVersion": 3,
  "requires": true,
  "packages": {
    "": {
      "name": "sample-vue-shared",
      "version": "1.0.0",
      "dependencies": {
        "@vue/shared": "3.5.41"
      }
    },
    "node_modules/@vue/shared": {
      "version": "3.5.41",
      "resolved": "https://registry.npmjs.org/@vue/shared/-/shared-3.5.41.tgz",
      "integrity": "sha512-IOnwSCma8j+9xJT6b8H0dEYidC80NsYmNMlZxRsukYcSoGaDBohog5hDxzeUXdFeGWFA++vWvxqOmrr96VlqMA==",
      "license": "MIT"
    }
  }
}

{
  "name": "sample-vue-shared",
  "version": "1.0.0",
  "type": "module",
  "private": true,
  "dependencies": {
    "@vue/shared": "3.5.41"
  }
}

{
  "schemaVersion": 1,
  "goal": "verify normalizeClass, normalizeStyle, and looseEqual in pkg:npm/%40vue/shared@3.5.41",
  "kind": "HOW",
  "packages": [
    "pkg:npm/%40vue/shared@3.5.41"
  ],
  "symbols": [
    "looseEqual",
    "normalizeClass",
    "normalizeStyle"
  ]
}

import assert from 'node:assert/strict';
import {
  normalizeClass,
  normalizeStyle,
  parseStringStyle,
  stringifyStyle,
  looseEqual,
  looseIndexOf
} from '@vue/shared';

// 1. normalizeClass flattens strings, string arrays, and object truthy boolean keys into space-separated class names
{
  assert.equal(normalizeClass('foo bar'), 'foo bar');
  assert.equal(normalizeClass(['foo', 'bar']), 'foo bar');
  assert.equal(normalizeClass({ foo: true, bar: false, baz: 1 }), 'foo baz');
}

// 2. normalizeClass recursively normalizes nested array and object structures and ignores falsy values
{
  assert.equal(
    normalizeClass(['foo', { bar: true, baz: false }, ['nested', { inner: true }], null, undefined, false]),
    'foo bar nested inner'
  );
  assert.equal(normalizeClass(null), '');
  assert.equal(normalizeClass(undefined), '');
  assert.equal(normalizeClass(false), '');
}

// 3. parseStringStyle converts css text into key-value style map and stringifyStyle serializes style objects
{
  assert.deepEqual(parseStringStyle('color: red; font-size: 14px;'), {
    color: 'red',
    'font-size': '14px'
  });
  assert.deepEqual(parseStringStyle('margin-top: 10px; opacity: 0.5;'), {
    'margin-top': '10px',
    opacity: '0.5'
  });
  assert.equal(stringifyStyle({ color: 'red', fontSize: '14px' }), 'color:red;font-size:14px;');
}

// 4. normalizeStyle preserves string styles, passes object styles, and merges array of styles
{
  assert.equal(normalizeStyle('color: red; font-size: 14px;'), 'color: red; font-size: 14px;');
  assert.deepEqual(normalizeStyle({ color: 'red', fontSize: '14px' }), {
    color: 'red',
    fontSize: '14px'
  });

  const merged = normalizeStyle([
    'color: red;',
    { fontSize: '12px' },
    { color: 'blue', fontWeight: 'bold' }
  ]);
  assert.deepEqual(merged, {
    color: 'blue',
    fontSize: '12px',
    fontWeight: 'bold'
  });
}

// 5. looseEqual performs deep structural equality comparison across primitives, dates, regexes, arrays, and objects
{
  assert.equal(looseEqual(1, 1), true);
  assert.equal(looseEqual('1', 1), true);
  assert.equal(looseEqual(new Date(1600000000000), new Date(1600000000000)), true);
  assert.equal(looseEqual(new Date(1600000000000), new Date(1700000000000)), false);
  assert.equal(looseEqual(/abc/g, /abc/g), true);
  assert.equal(looseEqual(/abc/g, /abc/i), false);
  assert.equal(looseEqual([1, 2, 3], [1, 2, 3]), true);
  assert.equal(looseEqual([1, 2], [1, 2, 3]), false);
  assert.equal(looseEqual({ a: 1, b: '2' }, { b: 2, a: 1 }), true);
}

// 6. looseIndexOf finds element index in array using looseEqual semantics
{
  const list = [1, { id: 1 }, { id: 2 }];
  assert.equal(looseIndexOf(list, { id: 1 }), 1);
  assert.equal(looseIndexOf(list, { id: 2 }), 2);
  assert.equal(looseIndexOf(list, { id: 3 }), -1);
}