ElyOffice/crates/ely-mail-engine/tests/mime_tree.rs

use ely_mail_engine::{Draft, Mailbox, Part, build, read};

/// Lines joined with CRLF, as servers send them.
fn crlf(lines: &[&str]) -> Vec<u8> {
    lines.join("\r\n").into_bytes()
}

fn part(name: Option<&str>, kind: &str, id: Option<&str>, bytes: &[u8]) -> Part {
    Part {
        name: name.map(str::to_owned),
        content_type: kind.to_owned(),
        params: Vec::new(),
        content_id: id.map(str::to_owned),
        bytes: bytes.to_vec(),
    }
}

#[test]
fn text_attachments_keep_their_own_bytes() {
    let mail = read(&crlf(&[
        "Content-Type: multipart/mixed; boundary=b",
        "",
        "--b",
        "Content-Type: text/plain",
        "",
        "body",
        "--b",
        "Content-Type: text/plain; charset=iso-8859-1",
        "Content-Transfer-Encoding: quoted-printable",
        "Content-Disposition: attachment; filename=qp.txt",
        "",
        "Caf=E9",
        "--b",
        "Content-Type: text/plain; charset=iso-8859-1",
        "Content-Disposition: attachment; filename=raw.txt",
        "",
        "Caf\u{e9}",
        "--b",
        "Content-Type: text/plain; charset=iso-8859-1",
        "Content-Transfer-Encoding: base64",
        "Content-Disposition: attachment; filename=b64.txt",
        "",
        "Q2Fm6Q==",
        "--b--",
        "",
    ]))
    .unwrap();
    assert_eq!(mail.text.as_deref(), Some("body"));
    let bytes: Vec<&[u8]> = mail
        .attachments
        .iter()
        .map(|p| p.bytes.as_slice())
        .collect();
    assert_eq!(bytes, [b"Caf\xe9", "Caf\u{e9}".as_bytes(), b"Caf\xe9"]);
}

#[test]
fn a_built_latin1_text_attachment_reads_back_as_built() {
    let latin1 = part(Some("cafe.txt"), "text/plain", None, b"Caf\xe9\r\n");
    let draft = Draft {
        from: Mailbox {
            name: None,
            email: "a@example.com".into(),
        },
        to: Vec::new(),
        cc: Vec::new(),
        subject: "s".into(),
        text: "t".into(),
        html: None,
        attachments: vec![latin1.clone()],
        in_reply_to: None,
        references: Vec::new(),
        date: 0,
    };
    let back = read(&build(&draft).unwrap().bytes).unwrap();
    assert_eq!(back.attachments, [latin1]);
}

#[test]
fn a_related_root_named_by_start_can_come_after_its_image() {
    let mail = read(&crlf(&[
        "Content-Type: multipart/related; boundary=r; type=\"text/html\"; start=\"<root@example.com>\"",
        "",
        "--r",
        "Content-Type: image/png",
        "Content-ID: <img@example.com>",
        "Content-Transfer-Encoding: base64",
        "",
        "iVBORw==",
        "--r",
        "Content-Type: text/html",
        "Content-ID: <root@example.com>",
        "",
        "<img src=\"cid:img@example.com\">",
        "--r--",
        "",
    ]))
    .unwrap();
    assert_eq!(
        mail.html.as_deref(),
        Some("<img src=\"cid:img@example.com\">")
    );
    assert_eq!(
        mail.inline,
        [part(None, "image/png", Some("img@example.com"), b"\x89PNG")]
    );
    assert!(mail.attachments.is_empty());
}

#[test]
fn a_related_image_marked_attachment_is_still_a_cid_target() {
    let mail = read(&crlf(&[
        "Content-Type: multipart/related; boundary=r",
        "",
        "--r",
        "Content-Type: text/html",
        "",
        "<img src=\"cid:img@example.com\">",
        "--r",
        "Content-Type: image/png",
        "Content-ID: <img@example.com>",
        "Content-Disposition: attachment; filename=img.png",
        "Content-Transfer-Encoding: base64",
        "",
        "iVBORw==",
        "--r--",
        "",
    ]))
    .unwrap();
    assert_eq!(
        mail.inline,
        [part(
            Some("img.png"),
            "image/png",
            Some("img@example.com"),
            b"\x89PNG"
        )]
    );
    assert!(mail.attachments.is_empty());
}

#[test]
fn an_attached_multipart_is_one_attachment_and_no_body() {
    let entity = [
        "Content-Type: multipart/alternative; boundary=in",
        "Content-Disposition: attachment; filename=alternatives.mime",
        "",
        "--in",
        "Content-Type: text/plain",
        "",
        "private attachment",
        "--in--",
    ];
    let mut lines = vec![
        "Content-Type: multipart/mixed; boundary=out",
        "",
        "--out",
        "Content-Type: text/plain",
        "",
        "body",
        "--out",
    ];
    lines.extend(entity);
    lines.extend(["--out--", ""]);
    let mail = read(&crlf(&lines)).unwrap();
    assert_eq!(mail.text.as_deref(), Some("body"));
    assert_eq!(mail.attachments.len(), 1);
    let attached = &mail.attachments[0];
    assert_eq!(attached.name.as_deref(), Some("alternatives.mime"));
    assert_eq!(attached.content_type, "multipart/alternative");
    assert_eq!(attached.bytes, crlf(&entity));
}

#[test]
fn alternatives_of_one_type_are_chosen_not_joined() {
    let mail = read(&crlf(&[
        "Content-Type: multipart/alternative; boundary=a",
        "",
        "--a",
        "Content-Type: text/plain; charset=us-ascii",
        "",
        "Cafe",
        "--a",
        "Content-Type: text/plain; charset=utf-8",
        "",
        "Café",
        "--a",
        "Content-Type: text/calendar",
        "",
        "BEGIN:VCALENDAR",
        "--a--",
        "",
    ]))
    .unwrap();
    assert_eq!(mail.text.as_deref(), Some("Café"));
    assert_eq!(
        mail.attachments,
        [part(None, "text/calendar", None, b"BEGIN:VCALENDAR")]
    );
}

#[test]
fn a_digest_child_without_a_type_is_a_message() {
    let enclosed = "From: x@example.com\r\nSubject: inner\r\n\r\nhello";
    let mut lines = vec!["Content-Type: multipart/digest; boundary=d", "", "--d", ""];
    lines.push(enclosed);
    lines.extend(["--d--", ""]);
    let mail = read(&crlf(&lines)).unwrap();
    assert_eq!(mail.attachments.len(), 1);
    assert_eq!(mail.attachments[0].content_type, "message/rfc822");
    let inner = read(&mail.attachments[0].bytes).unwrap();
    assert_eq!(inner.subject.as_deref(), Some("inner"));
}