Setup Jest for Vue

jest.config.js

@@ -14,6 +14,7 @@ if (process.env.CI) {
 // eslint-disable-next-line import/no-commonjs
 module.exports = {
   testMatch: ['<rootDir>/spec/frontend/**/*_spec.js'],
+  moduleFileExtensions: ['js', 'json', 'vue'],
   moduleNameMapper: {
     '^~(.*)$': '<rootDir>/app/assets/javascripts$1',
     '^helpers(.*)$': '<rootDir>/spec/frontend/helpers$1',
@@ -26,4 +27,8 @@ module.exports = {
   reporters,
   setupTestFrameworkScriptFile: '<rootDir>/spec/frontend/test_setup.js',
   restoreMocks: true,
+  transform: {
+    '^.+\\.js$': 'babel-jest',
+    '^.+\\.vue$': 'vue-jest',
+  },
 };