test(labware-library): mock file-saver while using cypress

labware-library/cypress/integration/labware-creator/fileImport.spec.js

@@ -137,5 +137,9 @@ context('File Import', () => {
           })
         })
       })
+
+    cy.window()
+      .its('__lastSavedFileName__')
+      .should('equal', 'TestPro 15 Well Plate 5 µL.zip')
   })
 })

labware-library/cypress/mocks/file-saver.js

@@ -0,0 +1,6 @@
+// mock for 'file-saver' npm module
+
+export const saveAs = (blob, fileName) => {
+  global.__lastSavedBlobZip__ = blob
+  global.__lastSavedFileName__ = fileName
+}

labware-library/src/labware-creator/index.js

@@ -493,13 +493,7 @@ export const LabwareCreator = (): React.Node => {
             labwareTestProtocol({ pipetteName, definition: def })
           )
           zip.generateAsync({ type: 'blob' }).then(blob => {
-            if (global.Cypress) {
-              // HACK(IL, 2020-04-02): can't figure out a better way to do this yet
-              // https://docs.cypress.io/faq/questions/using-cypress-faq.html#Can-my-tests-interact-with-Redux-Vuex-data-store
-              global.__lastSavedBlobZip__ = blob
-            } else {
-              saveAs(blob, `${displayName}.zip`)
-            }
+            saveAs(blob, `${displayName}.zip`)
           })
 
           reportEvent({

labware-library/webpack.config.js

@@ -30,6 +30,13 @@ const envVars = passThruEnvVars.reduce(
   { ...envVarsWithDefaults }
 )
 
+const testAliases =
+  process.env.CYPRESS === '1'
+    ? {
+        'file-saver': path.resolve(__dirname, 'cypress/mocks/file-saver.js'),
+      }
+    : {}
+
 module.exports = merge(baseConfig, {
   entry: JS_ENTRY,
 
@@ -66,4 +73,8 @@ module.exports = merge(baseConfig, {
       },
     }),
   ],
+
+  resolve: {
+    alias: testAliases,
+  },
 })