Origin for each line in tests/utils.rs from check-in dd307557e6:

dd307557e6 2026-07-31        arcade: use smtp2tg::utils::{
dd307557e6 2026-07-31        arcade: 	validate,
dd307557e6 2026-07-31        arcade: 	RE_CLOSING,
dd307557e6 2026-07-31        arcade: 	RE_DOMAIN,
dd307557e6 2026-07-31        arcade: };
dd307557e6 2026-07-31        arcade: use stacked_errors::Result;
dd307557e6 2026-07-31        arcade: 
dd307557e6 2026-07-31        arcade: #[test]
dd307557e6 2026-07-31        arcade: fn test_validate_valid_html() -> Result<()> {
dd307557e6 2026-07-31        arcade: 	let html = "<p>Some <b>valid</b> HTML</p>";
dd307557e6 2026-07-31        arcade: 	let escaped = validate(html)?;
dd307557e6 2026-07-31        arcade: 	assert_eq!(escaped, "&lt;p&gt;Some &lt;b&gt;valid&lt;/b&gt; HTML&lt;/p&gt;");
dd307557e6 2026-07-31        arcade: 	Ok(())
dd307557e6 2026-07-31        arcade: }
dd307557e6 2026-07-31        arcade: 
dd307557e6 2026-07-31        arcade: #[test]
dd307557e6 2026-07-31        arcade: fn test_validate_closing_tag() -> Result<()> {
dd307557e6 2026-07-31        arcade: 	let html = "<p>Some <b>valid</b> HTML</p></code><a href='http://somewere.com'>Link injection!</a>";
dd307557e6 2026-07-31        arcade: 	assert!(validate(html).is_err());
dd307557e6 2026-07-31        arcade:     assert!(validate("</pre>").is_err());
dd307557e6 2026-07-31        arcade:     assert!(validate("</code>").is_err());
dd307557e6 2026-07-31        arcade:     assert!(validate("</pre>\n").is_err());
dd307557e6 2026-07-31        arcade:     assert!(validate("</code>\t").is_err());
dd307557e6 2026-07-31        arcade: 	Ok(())
dd307557e6 2026-07-31        arcade: }
dd307557e6 2026-07-31        arcade: 
dd307557e6 2026-07-31        arcade: #[test]
dd307557e6 2026-07-31        arcade: fn test_validate_empty_string() -> Result<()> {
dd307557e6 2026-07-31        arcade: 	assert_eq!(validate("").unwrap(), "");
dd307557e6 2026-07-31        arcade: 	Ok(())
dd307557e6 2026-07-31        arcade: }
dd307557e6 2026-07-31        arcade: 
dd307557e6 2026-07-31        arcade: #[test]
dd307557e6 2026-07-31        arcade: fn test_validate_whitespace() -> Result<()> {
dd307557e6 2026-07-31        arcade: 	assert_eq!(validate("   \t\n").unwrap(), "   \t\n"); // no escaping for whitespace
dd307557e6 2026-07-31        arcade: 	Ok(())
dd307557e6 2026-07-31        arcade: }
dd307557e6 2026-07-31        arcade: 
dd307557e6 2026-07-31        arcade: #[test]
dd307557e6 2026-07-31        arcade: fn test_regex_closing_tag_matches() {
dd307557e6 2026-07-31        arcade: 	assert!(RE_CLOSING.is_match("</pre>"));
dd307557e6 2026-07-31        arcade: 	assert!(RE_CLOSING.is_match("</code>\t>"));
dd307557e6 2026-07-31        arcade: 	assert!(!RE_CLOSING.is_match("</div>")); // Not a pre/code tag
dd307557e6 2026-07-31        arcade: }
dd307557e6 2026-07-31        arcade: 
dd307557e6 2026-07-31        arcade: #[test]
dd307557e6 2026-07-31        arcade: fn test_regex_domain_matches() {
dd307557e6 2026-07-31        arcade: 	assert!(RE_DOMAIN.is_match("example.com"));
dd307557e6 2026-07-31        arcade: 	assert!(RE_DOMAIN.is_match("sub.example.co.uk"));
dd307557e6 2026-07-31        arcade: 	assert!(!RE_DOMAIN.is_match("invalid@domain.com"));
dd307557e6 2026-07-31        arcade: }