Chore: log actual error message (#343)

* Chore: log actual error message

* Chore: Fix style

* Chore: Responding to comments

src/lib/Preview.js

@@ -1056,18 +1056,14 @@ class Preview extends EventEmitter {
         // Destroy anything still showing
         this.destroy();
 
-        // Figure out what error message to log and what error message to display
-        const logMessage = err instanceof Error ? err.message : __('error_default');
-        const displayMessage = err && err.displayMessage ? err.displayMessage : logMessage;
-
         // Instantiate the error viewer
         this.viewer = this.getErrorViewer();
 
         // Add listeners for viewer events
         this.attachViewerListeners();
 
         // Load the error viewer
-        this.viewer.load(displayMessage);
+        this.viewer.load(err);
     }
 
     /**

src/lib/__tests__/Preview-test.js

@@ -1696,11 +1696,12 @@ describe('lib/Preview', () => {
         });
 
         it('should get the error viewer, attach viewer listeners, and load the error viewer', () => {
-            preview.triggerError();
+            const err = new Error();
+            preview.triggerError(err);
 
             expect(stubs.getErrorViewer).to.be.called;
             expect(stubs.attachViewerListeners).to.be.called;
-            expect(ErrorViewer.load).to.be.called;
+            expect(ErrorViewer.load).to.be.calledWith(err);
         });
     });
 

src/lib/viewers/doc/DocBaseViewer.js

@@ -501,6 +501,7 @@ class DocBaseViewer extends BaseViewer {
                 if (err instanceof Error) {
                     error.displayMessage = __('error_document');
                 }
+
                 this.triggerError(err);
             });
     }

src/lib/viewers/error/PreviewErrorViewer.js

@@ -52,15 +52,14 @@ class PreviewErrorViewer extends BaseViewer {
     /**
      * Shows an error message to the user.
      *
-     * @param {string} reason - Error reason
+     * @param {Error} err - Error
      * @return {void}
      */
-    load(reason) {
+    load(err) {
         this.setup();
 
         const { file, showDownload } = this.options;
         let icon = ICON_FILE_DEFAULT;
-        const message = reason || __('error_default');
 
         // Generic errors will not have the file object
         if (file) {
@@ -77,17 +76,27 @@ class PreviewErrorViewer extends BaseViewer {
             }
         }
 
+        /* eslint-disable no-param-reassign */
+        err = err instanceof Error ? err : new Error(__('error_default'));
+        /* eslint-enable no-param-reassign */
+
+        // If there is no display message fallback to the message from above
+        const displayMessage = err.displayMessage || err.message;
+
         this.iconEl.innerHTML = icon;
-        this.messageEl.textContent = message;
+        this.messageEl.textContent = displayMessage;
 
         // Add optional download button
         if (checkPermission(file, PERMISSION_DOWNLOAD) && showDownload && Browser.canDownload()) {
             this.addDownloadButton();
         }
 
         this.loaded = true;
+
+        // The error will either be the message from the original error, the displayMessage from the orignal error,
+        // or the default message from the locally created error
         this.emit('load', {
-            error: message
+            error: err.message || displayMessage
         });
     }
 

src/lib/viewers/error/__tests__/PreviewErrorViewer-test.js

@@ -64,12 +64,13 @@ describe('lib/viewers/error/PreviewErrorViewer', () => {
                 const extension = testCase[0];
                 const expectedIcon = testCase[1];
 
-                const message = 'reason';
+                const err = new Error();
+                err.displayMessage = 'reason';
                 error.options.file.extension = extension;
-                error.load(message);
+                error.load(err);
 
                 expect(error.iconEl).to.contain.html(expectedIcon);
-                expect(error.messageEl.textContent).to.equal(message);
+                expect(error.messageEl.textContent).to.equal(err.displayMessage);
             });
         });
 
@@ -112,17 +113,36 @@ describe('lib/viewers/error/PreviewErrorViewer', () => {
             expect(error.addDownloadButton).to.not.be.called;
         });
 
-        it('should broadcast load', () => {
+        it('should broadcast the log message', () => {
             sandbox.stub(error, 'emit');
 
-            const message = 'reason';
-            error.load(message);
+            const err = new Error();
+            err.displayMessage = 'reason';
+            err.message = 'this is bad';
+
+            error.load(err);
+
+            expect(error.emit).to.be.calledWith(
+                'load', {
+                    error: 'this is bad'
+                }
+            );
+        });
+
+        it('should broadcast the display message if there is no log message', () => {
+            sandbox.stub(error, 'emit');
+
+            const err = new Error();
+            err.displayMessage = 'reason';
+            err.message = undefined;
+
+            error.load(err);
+
 
             expect(error.emit).to.be.calledWith(
-                'load',
-                sinon.match({
-                    error: message
-                })
+                'load', {
+                    error: 'reason'
+                }
             );
         });
     });