Fix: Only check flash for SWF files (#747)

.gitignore

@@ -10,3 +10,4 @@ dist
 src/i18n/json
 jsconfig.json
 functional-tests/output
+yarn-error.log

src/lib/viewers/swf/SWFLoader.js

@@ -29,11 +29,12 @@ class SWFLoader extends AssetLoader {
      * @inheritdoc
      */
     determineViewer(file, disabledViewers = []) {
-        if (!Browser.hasFlash()) {
+        const viewer = super.determineViewer(file, disabledViewers);
+        if (viewer && !Browser.hasFlash()) {
             throw new PreviewError(ERROR_CODE.FLASH_NOT_ENABLED, __('error_flash_not_enabled'));
         }
 
-        return super.determineViewer(file, disabledViewers);
+        return viewer;
     }
 }
 

src/lib/viewers/swf/__tests__/SWFLoader-test.js

@@ -1,26 +1,47 @@
+/* eslint-disable no-unused-expressions */
 import SWFLoader from '../SWFLoader';
 import AssetLoader from '../../AssetLoader';
 import Browser from '../../../Browser';
 import PreviewError from '../../../PreviewError';
 
 const sandbox = sinon.sandbox.create();
+let file;
 
 describe('lib/viewers/SWFLoader', () => {
     afterEach(() => {
         sandbox.verifyAndRestore();
     });
 
     describe('determineViewer()', () => {
+        beforeEach(() => {
+            file = {
+                extension: 'swf',
+                representations: {
+                    entries: [
+                        {
+                            representation: 'ORIGINAL'
+                        }
+                    ]
+                }
+            };
+        });
+
         it('should throw a preview error if flash is not supported', () => {
             sandbox.stub(Browser, 'hasFlash').returns(false);
-            expect(() => SWFLoader.determineViewer()).to.throw(PreviewError);
+            expect(() => SWFLoader.determineViewer(file)).to.throw(PreviewError);
         });
 
         it('should call the superclass determineViewer if flash is suported', () => {
             sandbox.stub(Browser, 'hasFlash').returns(true);
             const stub = sandbox.stub(AssetLoader.prototype, 'determineViewer');
-            SWFLoader.determineViewer();
-            expect(stub).to.have.been.called; // eslint-disable-line no-unused-expressions
+            SWFLoader.determineViewer(file);
+            expect(stub).to.be.called;
+        });
+
+        it('should not check Flash if file is not SWF', () => {
+            sandbox.stub(Browser, 'hasFlash');
+            file.extension = 'jpg';
+            expect(Browser.hasFlash).to.not.be.called;
         });
     });
 });