cinny/src/app/utils/looksLikeCode.test.ts

import { describe, it } from 'node:test';
import assert from 'node:assert/strict';
import { looksLikeCode } from './looksLikeCode';

const code = (text: string, html?: string) => looksLikeCode(text, html);

describe('looksLikeCode: code', () => {
  it('JavaScript', () => {
    const r = code(`function add(a, b) {
  const sum = a + b;
  if (sum > 10) {
    return sum;
  }
  return 0;
}`);
    assert.equal(r.isCode, true);
    assert.equal(r.lang, 'js');
  });

  it('TypeScript', () => {
    const r = code(`interface User {
  id: string;
  name: string;
}
const u: User = { id: '1', name: 'a' };`);
    assert.deepEqual(r, { isCode: true, lang: 'ts' });
  });

  it('Python', () => {
    const r = code(`def greet(name):
    if not name:
        return "hi"
    return f"hi {name}"
print(greet("bob"))`);
    assert.deepEqual(r, { isCode: true, lang: 'python' });
  });

  it('SQL', () => {
    const r = code(`SELECT id, name
FROM users
WHERE active = 1
ORDER BY name;`);
    assert.deepEqual(r, { isCode: true, lang: 'sql' });
  });

  it('Rust', () => {
    const r = code(`pub fn main() {
    let mut total = 0;
    for i in 0..10 {
        total += i;
    }
}`);
    assert.deepEqual(r, { isCode: true, lang: 'rust' });
  });

  it('config-ish JSON without a language guess', () => {
    const r = code(`{
  "name": "lotus",
  "version": "1.0.0",
  "private": true
}`);
    assert.equal(r.isCode, true);
  });

  it('an editor paste carrying monospace HTML counts as a signal', () => {
    const text = `server {
  listen 443 ssl;
  server_name chat.example.org;
}`;
    assert.equal(code(text, '<div style="font-family: Menlo, monospace">x</div>').isCode, true);
  });
});

describe('looksLikeCode: not code', () => {
  it('fewer than three lines', () => {
    assert.equal(code('const a = 1;\nconst b = 2;').isCode, false);
  });

  it('prose with line breaks', () => {
    assert.equal(
      code(`Hey, are we still on for tonight?
I can bring snacks if someone else handles drinks.
Let me know what time works, I'm free after six.`).isCode,
      false,
    );
  });

  it('a long paragraph pasted as lines', () => {
    const line =
      'This is a long sentence about the plan. It keeps going for a while. And then some more words follow here.';
    assert.equal(code([line, line, line].join('\n')).isCode, false);
  });

  it('a markdown list', () => {
    assert.equal(
      code(`- milk (2 litres)
- eggs: a dozen
- bread, the good kind
- coffee!`).isCode,
      false,
    );
  });

  it('a quoted reply', () => {
    assert.equal(
      code(`> const a = 1;
> if (a) { run(); }
> return a;`).isCode,
      false,
    );
  });

  it('a list of links', () => {
    assert.equal(
      code(`https://example.org/a?b=1
https://example.org/c
https://example.org/d;e`).isCode,
      false,
    );
  });

  it('a log excerpt', () => {
    assert.equal(
      code(`2026-09-25 10:00:01 INFO server started
2026-09-25 10:00:02 INFO listening on 8008
2026-09-25 10:00:05 WARN slow request 1200ms`).isCode,
      false,
    );
  });
});