Function test_diff_permanent_basic

tests/integration_tests.rs:152–160

()

#[test]
fn test_diff_permanent_basic() {
    let mut args: Vec<String> = vec!["-d=permanent".into(), "--chgexit".into(), "--".into()];
    args.extend(echo_cmd("bar"));
    let args_ref: Vec<&str> = args.iter().map(|s| s.as_str()).collect();
    let (ok, out, _) = run_rwatch(&args_ref);
    assert!(ok);
    assert!(has_diff_line(&out, ' ', "bar") || has_diff_line(&out, '+', "bar"),
        "diff output should contain bar; lines: {:?}", out.lines().collect::<Vec<_>>());
}

/// Bug fix verification: permanent diff must compare against the FIRST run's output,
/// not against the empty string that was erroneously used before the fix.