Add unit tests for app/utils/images (#8134)

app/utils/images/index.test.ts

@@ -0,0 +1,152 @@
+// Copyright (c) 2015-present Mattermost, Inc. All Rights Reserved.
+// See LICENSE.txt for license information.
+
+import {Dimensions} from 'react-native';
+
+import {IMAGE_MAX_HEIGHT} from '@constants/image';
+
+import {
+    calculateDimensions,
+    getViewPortWidth,
+    isGifTooLarge,
+} from './index';
+
+jest.mock('react-native', () => ({
+    Dimensions: {
+        get: jest.fn(() => ({width: 800, height: 600})),
+    },
+}));
+
+jest.mock('@constants/image', () => ({
+    IMAGE_MAX_HEIGHT: 800,
+    IMAGE_MIN_DIMENSION: 50,
+    MAX_GIF_SIZE: 1000000,
+    VIEWPORT_IMAGE_OFFSET: 20,
+    VIEWPORT_IMAGE_REPLY_OFFSET: 40,
+}));
+
+jest.mock('@constants', () => ({
+    View: {
+        TABLET_SIDEBAR_WIDTH: 100,
+    },
+}));
+
+describe('calculateDimensions', () => {
+    it('should return 0 dimensions when height and width are not provided', () => {
+        const result = calculateDimensions();
+        expect(result).toEqual({height: 0, width: 0});
+    });
+
+    it('should return correct dimensions when width exceeds viewport width', () => {
+        const result = calculateDimensions(200, 400, 300);
+        expect(result).toEqual({height: 150, width: 300});
+    });
+
+    it('should assign imageHeight as IMAGE_MAX_HEIGHT when imageHeight exceeds IMAGE_MAX_HEIGHT and viewPortHeight is undefined', () => {
+        const result = calculateDimensions(900, 400, 600);
+        expect(result).toEqual({
+            height: IMAGE_MAX_HEIGHT,
+            width: IMAGE_MAX_HEIGHT * (400 / 900),
+        });
+    });
+
+    it('should return minimum dimensions when width is less than IMAGE_MIN_DIMENSION', () => {
+        const result = calculateDimensions(20, 30, 100);
+        expect(result).toEqual({height: 50, width: 75});
+    });
+
+    it('should return correct dimensions when height exceeds IMAGE_MAX_HEIGHT', () => {
+        const result = calculateDimensions(900, 500, 600, 700);
+        expect(result).toEqual({height: 700, width: 388.8888888888889});
+    });
+
+    it('should return minimum dimensions when height is less than IMAGE_MIN_DIMENSION', () => {
+        const result = calculateDimensions(30, 40, 100);
+        expect(result).toEqual({height: 50, width: 66.66666666666666});
+    });
+
+    it('should assign imageHeight as viewPortHeight when imageHeight exceeds viewPortHeight and viewPortHeight is less than IMAGE_MAX_HEIGHT', () => {
+        const result = calculateDimensions(900, 400, 600, 700);
+        expect(result).toEqual({
+            height: 700,
+            width: 700 * (400 / 900),
+        });
+    });
+
+    it('should assign imageHeight and imageWidth based on IMAGE_MIN_DIMENSION when imageHeight is less than IMAGE_MIN_DIMENSION and fits within viewPortWidth', () => {
+        const result = calculateDimensions(20, 40, 100);
+        expect(result).toEqual({
+            height: 50,
+            width: 50 * (40 / 20),
+        });
+    });
+
+    it('should assign imageHeight and imageWidth based on viewPortHeight when imageHeight exceeds viewPortHeight', () => {
+        const result = calculateDimensions(600, 400, 500, 300);
+        expect(result).toEqual({
+            height: 300,
+            width: 300 * (400 / 600),
+        });
+    });
+
+    it('should assign imageHeight and imageWidth based on viewPortHeight when imageHeight exceeds viewPortHeight and previous conditions are not met', () => {
+        const result = calculateDimensions(1700, 900, 1000, 900);
+        expect(result).toEqual({
+            height: 900,
+            width: 900 * (900 / 1700),
+        });
+    });
+});
+
+describe('getViewPortWidth', () => {
+    beforeEach(() => {
+        (Dimensions.get as jest.Mock).mockReturnValue({width: 800, height: 600});
+    });
+
+    it('should calculate viewport width for normal post', () => {
+        const result = getViewPortWidth(false);
+        expect(result).toBe(580);
+    });
+
+    it('should calculate viewport width for reply post', () => {
+        const result = getViewPortWidth(true);
+        expect(result).toBe(540);
+    });
+
+    it('should calculate viewport width for tablet offset', () => {
+        const result = getViewPortWidth(false, true);
+        expect(result).toBe(480);
+    });
+
+    it('should calculate viewport width for reply post with tablet offset', () => {
+        const result = getViewPortWidth(true, true);
+        expect(result).toBe(440);
+    });
+});
+
+describe('isGifTooLarge', () => {
+    it('should return false if image is not a gif', () => {
+        const result = isGifTooLarge({format: 'jpg', frame_count: 1, height: 500, width: 500});
+        expect(result).toBe(false);
+    });
+
+    it('should return false if image metadata is undefined', () => {
+        const result = isGifTooLarge(undefined);
+        expect(result).toBe(false);
+    });
+
+    it('should return true if gif is too large', () => {
+        const result = isGifTooLarge({format: 'gif', frame_count: 100, height: 1000, width: 1000});
+        expect(result).toBe(true);
+    });
+
+    it('should return false if gif is not too large', () => {
+        const result = isGifTooLarge({format: 'gif', frame_count: 10, height: 100, width: 100});
+        expect(result).toBe(false);
+    });
+
+    it('should return false if gif does not specify frame count', () => {
+        const result = isGifTooLarge({format: 'gif', height: 100, width: 100});
+        expect(result).toBe(false);
+    });
+});

app/utils/images/index.ts

@@ -2,7 +2,6 @@
 // See LICENSE.txt for license information.
 
 import {Dimensions} from 'react-native';
-import 'react-native-reanimated';
 
 import {View} from '@constants';
 import {IMAGE_MAX_HEIGHT, IMAGE_MIN_DIMENSION, MAX_GIF_SIZE, VIEWPORT_IMAGE_OFFSET, VIEWPORT_IMAGE_REPLY_OFFSET} from '@constants/image';