fix: adding e2e test instead for download errors

src/lib/viewers/error/PreviewErrorViewer.js

@@ -136,6 +136,7 @@ class PreviewErrorViewer extends BaseViewer {
     addDownloadButton() {
         this.downloadBtnEl = this.infoEl.appendChild(document.createElement('button'));
         this.downloadBtnEl.className = 'bp-btn bp-btn-primary';
+        this.downloadBtnEl.dataset.testid = 'preview-error-download-btn';
         this.downloadBtnEl.textContent = __('download');
         this.downloadBtnEl.addEventListener('click', this.download);
     }

test/integration/sanity/Download.e2e.test.js

@@ -0,0 +1,39 @@
+// <reference types='Cypress' />
+describe('Download disabled while preview is already open', () => {
+    const token = Cypress.env('ACCESS_TOKEN');
+    const fileIdBad = Cypress.env('FILE_ID_BAD');
+
+    beforeEach(() => {
+        cy.visit('/');
+    });
+
+    it('should give generic download error when trying to download and its forbidden', () => {
+        cy.showPreview(token, fileIdBad, { showDownload: true });
+        cy.route({
+            method: 'GET',
+            url: `**/files/${fileIdBad}?fields=download_url`,
+            status: 403,
+            response: {},
+        });
+
+        cy.getByTestId('preview-error-download-btn').should('be.visible');
+        cy.getByTestId('preview-error-download-btn').click();
+        cy.contains('Sorry! You can’t download this file.');
+    });
+
+    it('should give shield error when trying to download and access policy prevents download', () => {
+        cy.showPreview(token, fileIdBad, { showDownload: true });
+        cy.route({
+            method: 'GET',
+            url: `**/files/${fileIdBad}?fields=download_url`,
+            status: 403,
+            response: {
+                code: 'forbidden_by_policy',
+            },
+        });
+
+        cy.getByTestId('preview-error-download-btn').should('be.visible');
+        cy.getByTestId('preview-error-download-btn').click();
+        cy.contains('Downloading of this content has been disabled based on an access policy.');
+    });
+});