Altra conversione in Typescript , partendo da un progetto di esempio funzionante...

jest.config.js

@@ -0,0 +1,47 @@
+module.exports = {
+  globals: {
+    __DEV__: true
+  },
+  verbose: true,
+  testURL: 'http://localhost/',
+  collectCoverage: false,
+  coverageDirectory: '<rootDir>/test/coverage',
+  collectCoverageFrom: [
+    '<rootDir>/src/components/**/*.vue',
+    '<rootDir>/src/layouts/**/*.vue',
+    '<rootDir>/src/pages/**/*.vue',
+    '<rootDir>/src/plugins/**/*.ts',
+    '<rootDir>/src/mixins/**/*.ts',
+    '<rootDir>/src/directives/**/*.ts'
+  ],
+  coverageThreshold: {
+    global: {
+      branches: 50,
+      functions: 50,
+      lines: 50,
+      statements: 50
+    }
+  },
+  testMatch: [
+    '<rootDir>/**/__tests__/**/*.spec.ts'
+  ],
+  moduleFileExtensions: [
+    'ts',
+    'js',
+    'json',
+    'vue'
+  ],
+  moduleNameMapper: {
+    '^vue$': '<rootDir>/node_modules/vue/dist/vue.common.js',
+    '^quasar$': '<rootDir>/tmp/quasar.common.js',
+    '^~/(.*)$': '<rootDir>/$1',
+    '^@/(.*)$': '<rootDir>/src/$1'
+  },
+  transform: {
+    '.*\\.vue$': '<rootDir>/node_modules/vue-jest',
+    '.*\\.ts$': '<rootDir>/node_modules/ts-jest'
+  },
+  snapshotSerializers: [
+    '<rootDir>/node_modules/jest-serializer-vue'
+  ]
+}