Make Cypress more stable & add e2e test for error events when upload fails

.eslintrc.js

@@ -417,7 +417,7 @@ module.exports = {
     },
     {
       files: ['e2e/**/*.ts', 'e2e/**/*.js'],
-      rules: { 'import/no-extraneous-dependencies': 'off' },
+      rules: { 'import/no-extraneous-dependencies': 'off', 'no-unused-expressions': 'off' },
     },
   ],
 }

e2e/cypress/integration/dashboard-tus.spec.ts

@@ -4,6 +4,9 @@ type Tus = BaseTus & {
   requests: { isPaused: boolean }
 }
 
+// NOTE: we have to use different files to upload per test
+// because we are uploading to https://tusd.tusdemo.net,
+// constantly uploading the same images gives a different cached result (or something).
 describe('Dashboard with Tus', () => {
   beforeEach(() => {
     cy.visit('/dashboard-tus')
@@ -13,6 +16,29 @@ describe('Dashboard with Tus', () => {
     cy.intercept('http://localhost:3020/search/unsplash/*').as('unsplash')
   })
 
+  it('should emit `error` and `upload-error` events on failed POST request', () => {
+    cy.get('@file-input').attachFile(['images/traffic.jpg'])
+
+    const error = cy.spy()
+    const uploadError = cy.spy()
+    cy.window().then(({ uppy }) => {
+      uppy.on('upload-error', uploadError)
+      uppy.on('error', error)
+    })
+
+    cy.get('.uppy-StatusBar-actionBtn--upload').click()
+
+    cy.intercept(
+      { method: 'POST', pathname: '/files', times: 1 },
+      { statusCode: 401, body: { code: 401, message: 'Expired JWT Token' } },
+    ).as('post')
+
+    cy.wait('@post').then(() =>  {
+      expect(error).to.be.called
+      expect(uploadError).to.be.called
+    })
+  })
+
   it('should upload cat image successfully', () => {
     cy.get('@file-input').attachFile('images/cat.jpg')
     cy.get('.uppy-StatusBar-actionBtn--upload').click()
@@ -23,7 +49,7 @@ describe('Dashboard with Tus', () => {
   })
 
   it('should start exponential backoff when receiving HTTP 429', () => {
-    cy.get('@file-input').attachFile(['images/cat.jpg', 'images/traffic.jpg'])
+    cy.get('@file-input').attachFile(['images/baboon.png'])
     cy.get('.uppy-StatusBar-actionBtn--upload').click()
 
     cy.intercept(