From a67863c5a255b12503c5018a321e6d3c227ed90b Mon Sep 17 00:00:00 2001
From: Miguel Alatzar <migbot@users.noreply.github.com>
Date: Mon, 22 Apr 2019 19:17:03 -0700
Subject: [PATCH] [MM-14669] Return null dimensions when height or width is
 falsy (#2681)

* Return 50x50 dimensions when height or width is 0

* Refactor image constants

* Return null dimensions when height or width is falsy
---
 app/constants/image.js   |  5 +++++
 app/utils/images.js      | 14 ++++++++++++--
 app/utils/images.test.js | 24 ++++++++++++++++++++++--
 3 files changed, 39 insertions(+), 4 deletions(-)
 create mode 100644 app/constants/image.js

diff --git a/app/constants/image.js b/app/constants/image.js
new file mode 100644
index 000000000..e5e61c557
--- /dev/null
+++ b/app/constants/image.js
@@ -0,0 +1,5 @@
+// Copyright (c) 2015-present Mattermost, Inc. All Rights Reserved.
+// See LICENSE.txt for license information.
+
+export const IMAGE_MAX_HEIGHT = 350;
+export const IMAGE_MIN_DIMENSION = 50;
diff --git a/app/utils/images.js b/app/utils/images.js
index 070fb6397..7a6ea019a 100644
--- a/app/utils/images.js
+++ b/app/utils/images.js
@@ -1,11 +1,21 @@
 // Copyright (c) 2015-present Mattermost, Inc. All Rights Reserved.
 // See LICENSE.txt for license information.
 
+import {
+    IMAGE_MAX_HEIGHT,
+    IMAGE_MIN_DIMENSION,
+} from 'app/constants/image';
+
 let previewComponents;
-const IMAGE_MAX_HEIGHT = 350;
-const IMAGE_MIN_DIMENSION = 50;
 
 export const calculateDimensions = (height, width, viewPortWidth = 0, viewPortHeight = 0) => {
+    if (!height || !width) {
+        return {
+            height: null,
+            width: null,
+        };
+    }
+
     const ratio = height / width;
     const heightRatio = width / height;
 
diff --git a/app/utils/images.test.js b/app/utils/images.test.js
index 554018c9c..d0866603d 100644
--- a/app/utils/images.test.js
+++ b/app/utils/images.test.js
@@ -2,12 +2,32 @@
 // See LICENSE.txt for license information.
 
 import {calculateDimensions} from 'app/utils/images';
+import {
+    IMAGE_MAX_HEIGHT,
+    IMAGE_MIN_DIMENSION,
+} from 'app/constants/image';
 
 const PORTRAIT_VIEWPORT = 315;
-const IMAGE_MAX_HEIGHT = 350;
-const IMAGE_MIN_DIMENSION = 50;
 
 describe('Images calculateDimensions', () => {
+    it('image with falsy height should return null height and width', () => {
+        const falsyHeights = [0, null, undefined, NaN, '', false];
+        falsyHeights.forEach((falsyHeight) => {
+            const {height, width} = calculateDimensions(falsyHeight, 20, PORTRAIT_VIEWPORT);
+            expect(height).toEqual(null);
+            expect(width).toEqual(null);
+        });
+    });
+
+    it('image with falsy width should return null height and width', () => {
+        const falsyWidths = [0, null, undefined, NaN, '', false];
+        falsyWidths.forEach((falsyWidth) => {
+            const {height, width} = calculateDimensions(20, falsyWidth, PORTRAIT_VIEWPORT);
+            expect(height).toEqual(null);
+            expect(width).toEqual(null);
+        });
+    });
+
     it('image smaller than 50x50 should return 50x50', () => {
         const {height, width} = calculateDimensions(20, 20, PORTRAIT_VIEWPORT);
         expect(height).toEqual(IMAGE_MIN_DIMENSION);