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

import { describe, it } from 'node:test';
import assert from 'node:assert/strict';
import {
  stripTrackingParams,
  stripTrackingParamsInHtml,
  stripTrackingParamsInText,
} from './urlTracking';

describe('stripTrackingParams', () => {
  it('removes utm_* and known global params, keeps the rest', () => {
    const out = stripTrackingParams(
      'https://example.com/a?utm_source=x&utm_medium=y&fbclid=abc&page=2&gclid=1',
    );
    assert.equal(out, 'https://example.com/a?page=2');
  });

  it('drops the dangling ? when every param was tracking', () => {
    assert.equal(
      stripTrackingParams('https://example.com/a?utm_source=x'),
      'https://example.com/a',
    );
  });

  it('returns the identical string when nothing changed', () => {
    const url = 'https://example.com/a?page=2#frag';
    assert.equal(stripTrackingParams(url), url);
  });

  it('preserves the fragment', () => {
    assert.equal(
      stripTrackingParams('https://example.com/a?utm_source=x#section-3'),
      'https://example.com/a#section-3',
    );
  });

  it('applies host rules only on that host', () => {
    assert.equal(
      stripTrackingParams('https://youtu.be/dQw4w9WgXcQ?si=abc123&t=42'),
      'https://youtu.be/dQw4w9WgXcQ?t=42',
    );
    assert.equal(
      stripTrackingParams('https://www.youtube.com/watch?v=dQw4w9WgXcQ&feature=share&si=x'),
      'https://www.youtube.com/watch?v=dQw4w9WgXcQ',
    );
    // `si` is not tracking elsewhere.
    const other = 'https://example.com/?si=keep';
    assert.equal(stripTrackingParams(other), other);
  });

  it('strips amazon affiliate/telemetry params and the /ref= path segment but keeps variant selectors', () => {
    assert.equal(
      stripTrackingParams(
        'https://www.amazon.com/dp/B000000000/ref=sr_1_3?crid=ABC&keywords=x&qid=1&sr=8-3&tag=aff-20&th=1&psc=1&pd_rd_r=zz',
      ),
      'https://www.amazon.com/dp/B000000000?keywords=x&th=1&psc=1',
    );
  });

  it('never rewrites matrix.to permalinks or non-http schemes', () => {
    const permalink = 'https://matrix.to/#/!room:example.org/$event?via=example.org&utm_source=x';
    assert.equal(stripTrackingParams(permalink), permalink);
    assert.equal(
      stripTrackingParams('mxc://example.org/abc?utm_source=x'),
      'mxc://example.org/abc?utm_source=x',
    );
    assert.equal(stripTrackingParams('mailto:a@b.c?utm_source=x'), 'mailto:a@b.c?utm_source=x');
  });

  it('returns unparseable input unchanged', () => {
    assert.equal(stripTrackingParams('https://'), 'https://');
    assert.equal(stripTrackingParams('not a url'), 'not a url');
  });

  it('is idempotent', () => {
    const once = stripTrackingParams('https://x.com/user/status/1?s=20&t=abc');
    assert.equal(once, 'https://x.com/user/status/1');
    assert.equal(stripTrackingParams(once), once);
  });
});

describe('stripTrackingParamsInText', () => {
  it('cleans every URL in a block of text and keeps trailing punctuation', () => {
    const text =
      'see https://a.example/p?utm_source=x. and (https://b.example/?id=1&fbclid=2) plus https://c.example/?keep=1';
    assert.equal(
      stripTrackingParamsInText(text),
      'see https://a.example/p. and (https://b.example/?id=1) plus https://c.example/?keep=1',
    );
  });

  it('returns the identical string when no URL changed', () => {
    const text = 'nothing https://c.example/?keep=1 here';
    assert.equal(stripTrackingParamsInText(text), text);
  });
});

describe('stripTrackingParamsInHtml', () => {
  it('unescapes & for parsing and re-escapes in the output', () => {
    const html =
      '<a href="https://a.example/p?id=1&amp;utm_source=x&amp;page=2">https://a.example/p?id=1&amp;utm_source=x&amp;page=2</a>';
    assert.equal(
      stripTrackingParamsInHtml(html),
      '<a href="https://a.example/p?id=1&amp;page=2">https://a.example/p?id=1&amp;page=2</a>',
    );
  });

  it('leaves markup untouched when nothing is stripped', () => {
    const html = '<p>hi <a href="https://a.example/?x=1">link</a></p>';
    assert.equal(stripTrackingParamsInHtml(html), html);
  });
});