test: percy visual testing (#1053)

* test: percy visual testing init

* Try PR checks with custom command

* Only run percy visual tests for PWA on merge for now

platform/viewer/cypress/integration/common/OHIFStandaloneViewer.spec.js

@@ -5,6 +5,8 @@ describe('OHIFStandaloneViewer', () => {
 
   it('loads route with at least 2 rows', () => {
     cy.screenshot();
+    cy.percySnapshot();
+
     cy.get('#studyListData tr')
       .its('length')
       .should('be.gt', 2);

platform/viewer/cypress/integration/common/OHIFStudyViewer.spec.js

@@ -12,6 +12,8 @@ describe('OHIF Study Viewer Page', () => {
 
   it('checks if series thumbnails are being displayed', () => {
     cy.screenshot();
+    cy.percySnapshot();
+
     cy.get('.ThumbnailEntryContainer')
       .its('length')
       .should('be.gt', 1);

platform/viewer/cypress/plugins/index.js

@@ -7,10 +7,10 @@
 // You can read more here:
 // https://on.cypress.io/plugins-guide
 // ***********************************************************
+let percyHealthCheck = require('@percy/cypress/task');
 
 // This function is called when a project is opened or re-opened (e.g. due to
 // the project's config changing)
-
 module.exports = (on, config) => {
   // `on` is used to hook into various events Cypress emits
   // `config` is the resolved Cypress config
@@ -24,4 +24,6 @@ module.exports = (on, config) => {
       return args;
     }
   });
+
+  on('task', percyHealthCheck);
 };

platform/viewer/cypress/support/commands.js

@@ -1,3 +1,4 @@
+import '@percy/cypress';
 import { DragSimulator } from '../helpers/DragSimulator.js';
 import {
   initCornerstoneToolsAliases,

platform/viewer/package.json

@@ -27,7 +27,7 @@
     "dev:viewer": "yarn run dev",
     "start": "yarn run dev",
     "test:e2e": "cypress open",
-    "test:e2e:ci": "cypress run",
+    "test:e2e:ci": "percy exec -- cypress run",
     "test:e2e:dist": "start-server-and-test test:e2e:serve http://localhost:3000 test:e2e:ci",
     "test:e2e:serve": "serve -n -l 3000 -s dist",
     "test:unit": "jest --watchAll",