1import { describe, expect, it } from "vite-plus/test";
2
3import { imageMimeType } from "./image.ts";
4
5describe("imageMimeType", () => {
6 it("recognizes a picture the file picker left untyped", () => {
7 // The document picker types every pick as a plain file, often with no mime at all.
8 expect(imageMimeType({ name: "IMG_4997.PNG", mimeType: "" })).toBe("image/png");
9 expect(imageMimeType({ name: "shot.jpg", mimeType: "application/octet-stream" })).toBe(
10 "image/jpeg",
11 );
12 });
13
14 it("trusts a declared supported type", () => {
15 expect(imageMimeType({ name: "no-extension", mimeType: "image/webp" })).toBe("image/webp");
16 expect(imageMimeType({ name: "x.png", mimeType: "image/png; charset=binary" })).toBe(
17 "image/png",
18 );
19 });
20
21 it("leaves images the provider cannot accept as files", () => {
22 // Promoting these would put an attachment on the image path that cannot be sent.
23 expect(imageMimeType({ name: "scan.heic", mimeType: "image/heic" })).toBeNull();
24 expect(imageMimeType({ name: "logo.svg", mimeType: "image/svg+xml" })).toBeNull();
25 });
26
27 it("leaves documents and videos alone", () => {
28 expect(imageMimeType({ name: "notes.txt", mimeType: "text/plain" })).toBeNull();
29 expect(imageMimeType({ name: "clip.mp4", mimeType: "video/mp4" })).toBeNull();
30 expect(imageMimeType({ name: "noext", mimeType: "" })).toBeNull();
31 });
32});
33
34describe("legacy attachments", () => {
35 it("recognizes a picture that was sent before pictures were typed by content", () => {
36 // Older messages recorded these as plain files; the bytes are still a picture, so the
37 // chat view can render a thumbnail rather than a download row.
38 expect(imageMimeType({ name: "IMG_4996.PNG", mimeType: "application/octet-stream" })).toBe(
39 "image/png",
40 );
41 expect(imageMimeType({ name: "1000000020.png", mimeType: "" })).toBe("image/png");
42 });
43});
44
45describe("a declared non-image type", () => {
46 it("wins over a misleading picture extension", () => {
47 // The filename fallback exists for attachments whose type was never recorded. A definite
48 // type is what the file actually is, so a `.png` name cannot promote a PDF to a picture.
49 expect(imageMimeType({ name: "report.png", mimeType: "application/pdf" })).toBeNull();
50 expect(imageMimeType({ name: "archive.jpg", mimeType: "application/zip" })).toBeNull();
51 expect(imageMimeType({ name: "clip.png", mimeType: "video/mp4" })).toBeNull();
52 });
53
54 it("still falls back when the type is absent or generic", () => {
55 expect(imageMimeType({ name: "IMG_4996.PNG", mimeType: "application/octet-stream" })).toBe(
56 "image/png",
57 );
58 expect(imageMimeType({ name: "1000000020.png", mimeType: "" })).toBe("image/png");
59 });
60});