Move the isPortraitOrientation helper function from web/base_viewer.js to web/ui_utils.js

A couple of basic unit-tests are added, and a manual `isLandscape` check (in `web/base_viewer.js`) is also converted to use the helper function instead.

test/unit/ui_utils_spec.js

@@ -15,7 +15,7 @@
 
 import {
   binarySearchFirstItem, EventBus, getPageSizeInches, getPDFFileNameFromURL,
-  isValidRotation, waitOnEventOrTimeout, WaitOnType
+  isPortraitOrientation, isValidRotation, waitOnEventOrTimeout, WaitOnType
 } from '../../web/ui_utils';
 import { createObjectURL } from '../../src/shared/util';
 import isNodeJS from '../../src/shared/is_node';
@@ -285,6 +285,27 @@ describe('ui_utils', function() {
     });
   });
 
+  describe('isPortraitOrientation', function() {
+    it('should be portrait orientation', function() {
+      expect(isPortraitOrientation({
+        width: 200,
+        height: 400,
+      })).toEqual(true);
+
+      expect(isPortraitOrientation({
+        width: 500,
+        height: 500,
+      })).toEqual(true);
+    });
+
+    it('should be landscape orientation', function() {
+      expect(isPortraitOrientation({
+        width: 600,
+        height: 300,
+      })).toEqual(false);
+    });
+  });
+
   describe('waitOnEventOrTimeout', function() {
     let eventBus;
 

web/base_viewer.js

@@ -14,9 +14,10 @@
  */
 
 import {
-  CSS_UNITS, DEFAULT_SCALE, DEFAULT_SCALE_VALUE, isValidRotation,
-  MAX_AUTO_SCALE, NullL10n, PresentationModeState, RendererType,
-  SCROLLBAR_PADDING, TextLayerMode, UNKNOWN_SCALE, VERTICAL_PADDING, watchScroll
+  CSS_UNITS, DEFAULT_SCALE, DEFAULT_SCALE_VALUE, isPortraitOrientation,
+  isValidRotation, MAX_AUTO_SCALE, NullL10n, PresentationModeState,
+  RendererType, SCROLLBAR_PADDING, TextLayerMode, UNKNOWN_SCALE,
+  VERTICAL_PADDING, watchScroll
 } from './ui_utils';
 import { PDFRenderingQueue, RenderingStates } from './pdf_rendering_queue';
 import { AnnotationLayerBuilder } from './annotation_layer_builder';
@@ -94,10 +95,6 @@ function isSameScale(oldScale, newScale) {
   return false;
 }
 
-function isPortraitOrientation(size) {
-  return size.width <= size.height;
-}
-
 /**
  * Simple viewer control to display PDF content/pages.
  * @implements {IRenderableView}
@@ -578,11 +575,10 @@ class BaseViewer {
           scale = Math.min(pageWidthScale, pageHeightScale);
           break;
         case 'auto':
-          let isLandscape = (currentPage.width > currentPage.height);
           // For pages in landscape mode, fit the page height to the viewer
           // *unless* the page would thus become too wide to fit horizontally.
-          let horizontalScale = isLandscape ?
-            Math.min(pageHeightScale, pageWidthScale) : pageWidthScale;
+          let horizontalScale = isPortraitOrientation(currentPage) ?
+            pageWidthScale : Math.min(pageHeightScale, pageWidthScale);
           scale = Math.min(MAX_AUTO_SCALE, horizontalScale);
           break;
         default:

web/ui_utils.js

@@ -439,6 +439,10 @@ function isValidRotation(angle) {
   return Number.isInteger(angle) && angle % 90 === 0;
 }
 
+function isPortraitOrientation(size) {
+  return size.width <= size.height;
+}
+
 function cloneObj(obj) {
   let result = Object.create(null);
   for (let i in obj) {
@@ -642,6 +646,7 @@ export {
   SCROLLBAR_PADDING,
   VERTICAL_PADDING,
   isValidRotation,
+  isPortraitOrientation,
   isFileSchema,
   cloneObj,
   PresentationModeState,