Link previews: show full size image less often

ts/test-both/linkPreviews/shouldUseFullSizeLinkPreviewImage_test.ts

@@ -0,0 +1,146 @@
+// Copyright 2021 Signal Messenger, LLC
+// SPDX-License-Identifier: AGPL-3.0-only
+
+import { assert } from 'chai';
+import { IMAGE_JPEG, VIDEO_MP4 } from '../../types/MIME';
+import { AttachmentType } from '../../types/Attachment';
+
+import { shouldUseFullSizeLinkPreviewImage } from '../../linkPreviews/shouldUseFullSizeLinkPreviewImage';
+
+describe('shouldUseFullSizeLinkPreviewImage', () => {
+  const baseLinkPreview = {
+    title: 'Foo Bar',
+    domain: 'example.com',
+    url: 'https://example.com/foo.html',
+    isStickerPack: false,
+  };
+
+  const fakeAttachment = (
+    overrides: Partial<AttachmentType> = {}
+  ): AttachmentType => ({
+    contentType: IMAGE_JPEG,
+    fileName: 'foo.jpg',
+    url: '/tmp/foo.jpg',
+    width: 800,
+    height: 600,
+    ...overrides,
+  });
+
+  it('returns false if there is no image', () => {
+    assert.isFalse(
+      shouldUseFullSizeLinkPreviewImage({
+        ...baseLinkPreview,
+      })
+    );
+  });
+
+  it('returns false is the preview is a sticker pack', () => {
+    assert.isFalse(
+      shouldUseFullSizeLinkPreviewImage({
+        ...baseLinkPreview,
+        isStickerPack: true,
+        image: fakeAttachment(),
+      })
+    );
+  });
+
+  it("returns false if either of the image's dimensions are missing", () => {
+    assert.isFalse(
+      shouldUseFullSizeLinkPreviewImage({
+        ...baseLinkPreview,
+        image: fakeAttachment({ width: undefined }),
+      })
+    );
+    assert.isFalse(
+      shouldUseFullSizeLinkPreviewImage({
+        ...baseLinkPreview,
+        image: fakeAttachment({ height: undefined }),
+      })
+    );
+    assert.isFalse(
+      shouldUseFullSizeLinkPreviewImage({
+        ...baseLinkPreview,
+        image: fakeAttachment({ width: undefined, height: undefined }),
+      })
+    );
+  });
+
+  it("returns false if either of the image's dimensions are <200px", () => {
+    assert.isFalse(
+      shouldUseFullSizeLinkPreviewImage({
+        ...baseLinkPreview,
+        image: fakeAttachment({ width: 199 }),
+      })
+    );
+    assert.isFalse(
+      shouldUseFullSizeLinkPreviewImage({
+        ...baseLinkPreview,
+        image: fakeAttachment({ height: 199 }),
+      })
+    );
+    assert.isFalse(
+      shouldUseFullSizeLinkPreviewImage({
+        ...baseLinkPreview,
+        image: fakeAttachment({ width: 150, height: 199 }),
+      })
+    );
+  });
+
+  it('returns false if the image is square', () => {
+    assert.isFalse(
+      shouldUseFullSizeLinkPreviewImage({
+        ...baseLinkPreview,
+        image: fakeAttachment({ width: 200, height: 200 }),
+      })
+    );
+    assert.isFalse(
+      shouldUseFullSizeLinkPreviewImage({
+        ...baseLinkPreview,
+        image: fakeAttachment({ width: 500, height: 500 }),
+      })
+    );
+  });
+
+  it('returns false if the image is roughly square', () => {
+    assert.isFalse(
+      shouldUseFullSizeLinkPreviewImage({
+        ...baseLinkPreview,
+        image: fakeAttachment({ width: 200, height: 201 }),
+      })
+    );
+    assert.isFalse(
+      shouldUseFullSizeLinkPreviewImage({
+        ...baseLinkPreview,
+        image: fakeAttachment({ width: 497, height: 501 }),
+      })
+    );
+  });
+
+  it("returns false for large attachments that aren't images", () => {
+    assert.isFalse(
+      shouldUseFullSizeLinkPreviewImage({
+        ...baseLinkPreview,
+        image: fakeAttachment({
+          contentType: VIDEO_MP4,
+          fileName: 'foo.mp4',
+          url: '/tmp/foo.mp4',
+        }),
+      })
+    );
+  });
+
+  it('returns true for larger images', () => {
+    assert.isTrue(
+      shouldUseFullSizeLinkPreviewImage({
+        ...baseLinkPreview,
+        image: fakeAttachment({ width: 200, height: 500 }),
+      })
+    );
+    assert.isTrue(
+      shouldUseFullSizeLinkPreviewImage({
+        ...baseLinkPreview,
+        image: fakeAttachment(),
+      })
+    );
+  });
+});